Abstract:
A method of linking an object to a print medium, comprising the step of: submitting a request to associate the object with a print media identifier of the print medium, submission of the request facilitating identification of the object and the print media identifier; wherein, the association of the object and the print media identifier is recorded in a database, the object being retrievable from the database using the print media identifier.

Description:
FIELD OF THE INVENTION 
   The present invention generally relates to a mobile device incorporating a printer. The invention more specifically relates to a mobile device such as a mobile telecommunications device, for example a mobile or cellular telephone that incorporates a printer which is able to print a wide variety of content on a print medium. However, it will be appreciated by those skilled in the art that the present invention can be used by other types of portable or mobile devices, or even non-portable devices. 
   COPENDING APPLICATIONS 
   The following applications have been filed by the applicant simultaneously with the present application: 
   
     
       
             
             
             
             
             
           
         
             
                 
             
           
           
             
               11/228,540 
               11/228,500 
               11/228,501 
               11/228,530 
               11/228,490 
             
             
               11/228,531 
               11/228,504 
               11/228,502 
               11/228,507 
               11/228,482 
             
             
               11/228,505 
               11/228,497 
               11/228,487 
               11/228,529 
               11/228,484 
             
             
               11/228,489 
               11/228,518 
               11/228,536 
               11/228,496 
               11/228,488 
             
             
               11/228,506 
               11/228,516 
               11/228,526 
               11/228,539 
               11/228,538 
             
             
               11/228,524 
               11/228,523 
               11/228,519 
               11/228,528 
               11/228,527 
             
             
               11/228,525 
               11/228,520 
               11/228,498 
               11/228,511 
               11/228,522 
             
             
               11/228,515 
               11/228,537 
               11/228,534 
               11/228,491 
               11/228,499 
             
             
               11/228,509 
               11/228,492 
               11/228,493 
               11/228,510 
               11/228,508 
             
             
               11/228,512 
               11/228,514 
               11/228,494 
               11/228,495 
               11/228,486 
             
             
               11/228,481 
               11/228,477 
               11/228,485 
               11/228,483 
               11/228,521 
             
             
               11/228,517 
               11/228,532 
               11/228,513 
               11/228,503 
               11/228,480 
             
             
               11/228,535 
               11/228,478 
             
             
                 
             
           
        
       
     
   
   The disclosures of these copending applications are incorporated herein by reference. 
   CROSS REFERENCES 
   The following patents or patent applications filed by the applicant or assignee of the present invention are hereby incorporated by cross-reference: 
   
     
       
             
             
             
             
             
             
             
           
         
             
                 
             
           
           
             
               10/815,621 
               10/815,612 
               10/815,630 
               10/815,637 
               10/815,638 
               10/815,640 
               10/815,642 
             
             
               10/815,643 
               10/815,644 
               10/815,618 
               10/815,639 
               10/815,635 
               10/815,647 
               10/815,634 
             
             
               10/815,632 
               10/815,631 
               10/815,648 
               10/815,641 
               10/815,645 
               10/815,646 
               10/815,617 
             
             
               10/815,620 
               10/815,615 
               10/815,613 
               10/815,633 
               10/815,619 
               10/815,616 
               10/815,614 
             
             
               10/815,636 
               10/815,649 
               11/041,650 
               11/041,651 
               11/041,652 
               11/041,649 
               11/041,610 
             
             
               11/041,609 
               11/041,626 
               11/041,627 
               11/041,624 
               11/041,625 
               11/041,556 
               11/041,580 
             
             
               11/041,723 
               11/041,698 
               11/041,648 
               10/815,609 
               10/815,627 
               10/815,626 
               10/815,610 
             
             
               10/815,611 
               10/815,623 
               10/815,622 
               10/815,629 
               10/815,625 
               10/815,624 
               10/815,628 
             
             
               10/913,375 
               10/913,373 
               10/913,374 
               10/913,372 
               10/913,377 
               10/913,378 
               10/913,380 
             
             
               10/913,379 
               10/913,376 
               10/913,381 
               10/986,402 
               11/172,816 
               11/172,815 
               11/172,814 
             
             
               10/409,876 
               10/409,848 
               10/409,845 
               11/084,796 
               11/084,742 
               11/084,806 
               09/575,197 
             
             
               09/575,195 
               09/575,159 
               09/575,132 
               09/575,123 
               09/575,148 
               09/575,130 
               09/575,165 
             
             
               09/575,153 
               09/693,415 
               09/575,118 
               09/609,139 
               09/608,970 
               09/575,131 
               09/575,116 
             
             
               09/575,144 
               09/575,139 
               09/575,186 
               6,681,045 
               6,678,499 
               6,679,420 
               09/663,599 
             
             
               09/607,852 
               6,728,000 
               09/693,219 
               09/575,145 
               09/607,656 
               09/693,280 
               6,766,942 
             
             
               09/693,515 
               09/663,701 
               09/575,192 
               6,720,985 
               09/609,303 
               09/610,095 
               09/609,596 
             
             
               09/693,705 
               09/693,647 
               09/721,895 
               09/721,894 
               09/60,7843 
               09/693,690 
               09/607,605 
             
             
               09/608,178 
               09/609,553 
               09/609,233 
               09/609,149 
               09/608,022 
               09/575,181 
               09/722,174 
             
             
               09/721,896 
               10/291,522 
               6,718,061 
               10/291,523 
               10/291,471 
               10/291,470 
               10/291,819 
             
             
               10/291,481 
               10/291,509 
               10/291,825 
               10/291,519 
               10/291,575 
               10/291,557 
               10/291,661 
             
             
               10/291,558 
               10/291,587 
               10/291,818 
               10/291,576 
               10/291,589 
               6,714,678 
               6,644,545 
             
             
               6,609,653 
               6,651,879 
               10/291,555 
               10/291,510 
               10/291,592 
               10/291,542 
               10/291,820 
             
             
               10/291,516 
               10/291,363 
               10/291,487 
               10/291,520 
               10/291,521 
               10/291,556 
               10/291,821 
             
             
               10/291,525 
               10/291,586 
               10/291,822 
               10/291,524 
               10/291,553 
               10/291,511 
               10/291,585 
             
             
               10/291,374 
               10/685,523 
               10/685,583 
               10/685,455 
               10/685,584 
               10/757,600 
               10/804,034 
             
             
               10/793,933 
               10/853,356 
               10/831,232 
               10/884,882 
               10/943,875 
               10/943,938 
               10/943,874 
             
             
               10/943,872 
               10/944,044 
               10/943,942 
               10/944,043 
               10/949,293 
               10/943,877 
               10/965,913 
             
             
               10/954,170 
               10/981,773 
               10/981,626 
               10/981,616 
               10/981,627 
               10/974,730 
               10/986,337 
             
             
               10/992,713 
               11/006,536 
               11/020,256 
               11/020,106 
               11/020,260 
               11/020,321 
               11/020,319 
             
             
               11/026,045 
               11/059,696 
               11/051,032 
               11/059,674 
               11/107,944 
               11/107,941 
               11/082,940 
             
             
               11/082,815 
               11/082,827 
               11/082,829 
               11/082,956 
               11/083,012 
               11/124,256 
               11/123,136 
             
             
               11/154,676 
               11/159,196 
               11/182,002 
               11/202,251 
               11/202,252 
               11/202,253 
               11/203,200 
             
             
               11/202,218 
               11/206,778 
               11/203,424 
               11/222,977 
               09/575,193 
               09/575,156 
               09/609,232 
             
             
               09/607,844 
               6,457,883 
               09/693,593 
               10/743,671 
               11/033,379 
               09/928,055 
               09/927,684 
             
             
               09/928,108 
               09/927,685 
               09/927,809 
               09/575,183 
               6,789,194 
               09/575,150 
               6,789,191 
             
             
               10/900,129 
               10/900,127 
               10/913,328 
               10/913,350 
               10/982,975 
               10/983,029 
               6,644,642 
             
             
               6,502,614 
               6,622,999 
               6,669,385 
               10/322,450 
               10/933,285 
               10/949,307 
               6,549,935 
             
             
               NPN004US 
               09/575,187 
               6,727,996 
               6,591,884 
               6,439,706 
               6,760,119 
               09/575,198 
             
             
               09/722,148 
               09/722,146 
               09/721,861 
               6,290,349 
               6,428,155 
               6,785,016 
               09/608,920 
             
             
               6,741,871 
               09/722,171 
               09/721,858 
               09/722,142 
               10/171,987 
               10/202,021 
               10/291,724 
             
             
               10/291,512 
               10/291,554 
               10/659,027 
               10/659,026 
               10/831,242 
               10/884,885 
               10/884,883 
             
             
               10/901,154 
               10/932,044 
               10/962,412 
               10/962,510 
               10/962,552 
               10/965,733 
               10/965,933 
             
             
               10/974,742 
               10/982,974 
               10/983,018 
               10/986,375 
               11/107,817 
               11/148,238 
               11/149,160 
             
             
               09/693,301 
               09/575,174 
               09/575,163 
               6,474,888 
               6,627,870 
               6,724,374 
               6,788,982 
             
             
               09/722,141 
               6,788,293 
               09/722,147 
               6,737,591 
               09/722,172 
               09/693,514 
               6,792,165 
             
             
               09/722,088 
               6,795,593 
               10/291,823 
               6,768,821 
               10/291,366 
               10/291,503 
               6,797,895 
             
             
               10/274,817 
               10/782,894 
               10/782,895 
               10/778,056 
               10/778,058 
               10/778,060 
               10/778,059 
             
             
               10/778,063 
               10/778,062 
               10/778,061 
               10/778,057 
               10/846,895 
               10/917,468 
               10/917,467 
             
             
               10/917,466 
               10/917,465 
               10/917,356 
               10/948,169 
               10/948,253 
               10/948,157 
               10/917,436 
             
             
               10/943,856 
               10/919,379 
               10/943,843 
               10/943,878 
               10/943,849 
               10/965,751 
               11/071,267 
             
             
               11/144,840 
               11/155,556 
               11/155,557 
               11/193,481 
               11/193,435 
               11/193,482 
               11/193,479 
             
             
               09/575,154 
               09/575,129 
               09/575,124 
               09/575,188 
               09/721,862 
               10/473,747 
               10/120,441 
             
             
               10/291,577 
               10/291,718 
               6,789,731 
               10/291,543 
               6,766,944 
               6,766,945 
               10/291,715 
             
             
               10/291,559 
               10/291,660 
               10/531,734 
               10/409,864 
               10/309,358 
               10/537,159 
               NPT022US 
             
             
               10/410,484 
               10/884,884 
               10/853,379 
               10/786,631 
               10/853,782 
               10/893,372 
               10/893,381 
             
             
               10/893,382 
               10/893,383 
               10/893,384 
               10/971,051 
               10/971,145 
               10/971,146 
               10/986,403 
             
             
               10/986,404 
               10/990,459 
               11/059,684 
               11/074,802 
               10/492,169 
               10/492,152 
               10/492,168 
             
             
               10/492,161 
               10/492,154 
               10/502,575 
               10/531,229 
               10/683,151 
               10/531,733 
               10/683,040 
             
             
               10/510,391 
               10/919,260 
               10/510,392 
               10/919,261 
               10/778,090 
               09/575,189 
               09/575,162 
             
             
               09/575,172 
               09/575,170 
               09/575,171 
               09/575,161 
               10/291,716 
               10/291,547 
               10/291,538 
             
             
               6,786,397 
               10/291,827 
               10/291,548 
               10/291,714 
               10/291,544 
               10/291,541 
               10/291,584 
             
             
               10/291,579 
               10/291,824 
               10/291,713 
               10/291,545 
               10/291,546 
               10/917,355 
               10/913,340 
             
             
               10/940,668 
               11/020,160 
               11/039,897 
               11/074,800 
               11/074,782 
               11/074,777 
               11/075,917 
             
             
               11/102,698 
               11/102,843 
               11/202,112 
               6,454,482 
               09/693,704 
               6,527,365 
               6,474,773 
             
             
               6,550,997 
               10/181,496 
               10/274,119 
               10/309,185 
               10/309,066 
               10/949,288 
               10/962,400 
             
             
               10/969,121 
               11/185,722 
               11/181,754 
               11/203,180 
               09/517,539 
               6,566,858 
               09/112,762 
             
             
               6,331,946 
               6,246,970 
               6,442,525 
               09/517,384 
               09/505,951 
               6,374,354 
               09/517,608 
             
             
               09/505,147 
               10/203,564 
               6,757,832 
               6,334,190 
               6,745,331 
               09/517,541 
               10/203,559 
             
             
               10/203,560 
               10/636,263 
               10/636,283 
               10/866,608 
               10/902,889 
               10/902,833 
               10/940,653 
             
             
               10/942,858 
               10/727,181 
               10/727,162 
               10/727,163 
               10/727,245 
               10/727,204 
               10/727,233 
             
             
               10/727,280 
               10/727,157 
               10/727,178 
               10/727,210 
               10/727,257 
               10/727,238 
               10/727,251 
             
             
               10/727,159 
               10/727,180 
               10/727,179 
               10/727,192 
               10/727,274 
               10/727,164 
               10/727,161 
             
             
               10/727,198 
               10/727,158 
               10/754,536 
               10/754,938 
               10/727,227 
               10/727,160 
               10/934,720 
             
             
               PEA30US 
               10/296,522 
               6,795,215 
               10/296,535 
               09/575,109 
               10/296,525 
               09/575,110 
             
             
               09/607,985 
               6,398,332 
               6,394,573 
               6,622,923 
               6,747,760 
               10/189,459 
               10/884,881 
             
             
               10/943,941 
               10/949,294 
               11/039,866 
               11/123,011 
               11/123,010 
               11/144,769 
               11/148,237 
             
             
               10/922,846 
               10/922,845 
               10/854,521 
               10/854,522 
               10/854,488 
               10/854,487 
               10/854,503 
             
             
               10/854,504 
               10/854,509 
               10/854,510 
               10/854,496 
               10/854,497 
               10/854,495 
               10/854,498 
             
             
               10/854,511 
               10/854,512 
               10/854,525 
               10/854,526 
               10/854,516 
               10/854,508 
               10/854,507 
             
             
               10/854,515 
               10/854,506 
               10/854,505 
               10/854,493 
               10/854,494 
               10/854,489 
               10/854,490 
             
             
               10/854,492 
               10/854,491 
               10/854,528 
               10/854,523 
               10/854,527 
               10/854,524 
               10/854,520 
             
             
               10/854,514 
               10/854,519 
               10/854,513 
               10/854,499 
               10/854,501 
               10/854,500 
               10/854,502 
             
             
               10/854,518 
               10/854,517 
               10/934,628 
               PLT046US 
               6,405,055 
               6,628,430 
               10/920,230 
             
             
               10/920,372 
               10/920,229 
               10/919,366 
               10/919,241 
               10/919,242 
               10/919,243 
               10/919,380 
             
             
               10/919,381 
               10/919,382 
               10/919,383 
               10/920,371 
               10/503,924 
               10/503,901 
               10/159,626 
             
             
               10/159,035 
               10/659,023 
               10/659,022 
               10/920,219 
               10/920,218 
               10/920,220 
               10/920,225 
             
             
               11/107,942 
               11/107,943 
               BAL119US 
               10/659,025 
               10/659,024 
               10/920,221 
               10/920,280 
             
             
               11/124,158 
               11/124,196 
               11/124,199 
               11/124,162 
               11/124,202 
               11/124,197 
               11/124,154 
             
             
               11/124,198 
               11/124,153 
               11/124,151 
               11/124,160 
               11/124,192 
               11/124,175 
               11/124,163 
             
             
               11/124,149 
               11/124,152 
               11/124,173 
               11/124,155 
               11/124,157 
               11/124,174 
               11/124,194 
             
             
               11/124,164 
               11/124,200 
               11/124,195 
               11/124,166 
               11/124,150 
               11/124,172 
               11/124,165 
             
             
               11/124,186 
               11/124,185 
               11/124,184 
               11/124,182 
               11/124,201 
               11/124,171 
               11/124,181 
             
             
               11/124,161 
               11/124,156 
               11/124,191 
               11/124,159 
               11/124,175 
               11/124,188 
               11/124,170 
             
             
               11/124,187 
               11/124,189 
               11/124,190 
               11/124,180 
               11/124,193 
               11/124,183 
               11/124,178 
             
             
               11/124,177 
               11/124,148 
               11/124,168 
               11/124,167 
               11/124,179 
               11/124,169 
               11/187,976 
             
             
               11/188,011 
               11/188,014 
               10/980,187 
               11/003,786 
               11/003,354 
               11/003,616 
               11/003,418 
             
             
               11/003,334 
               11/003,600 
               11/003,404 
               11/003,419 
               11/003,700 
               11/003,601 
               11/003,618 
             
             
               11/003,615 
               11/003,337 
               11/003,698 
               11/003,420 
               11/003,682 
               11/003,699 
               11/071,473 
             
             
               11/003,463 
               11/003,701 
               11/003,683 
               11/003,614 
               11/003,702 
               11/003,684 
               11/003,619 
             
             
               11/003,617 
               10/760,254 
               10/760,210 
               10/760,202 
               10/760,197 
               10/760,198 
               10/760,249 
             
             
               10/760,263 
               10/760,196 
               10/760,247 
               10/760,223 
               10/760,264 
               10/760,244 
               10/760,245 
             
             
               10/760,222 
               10/760,248 
               10/760,236 
               10/760,192 
               10/760,203 
               10/760,204 
               10/760,205 
             
             
               10/760,206 
               10/760,267 
               10/760,270 
               10/760,259 
               10/760,271 
               10/760,275 
               10/760,274 
             
             
               10/760,268 
               10/760,184 
               10/760,195 
               10/760,186 
               10/760,261 
               10/760,258 
               11/014,764 
             
             
               11/014,763 
               11/014,748 
               11/014,747 
               11/014,761 
               11/014,760 
               11/014,757 
               11/014,714 
             
             
               11/014,713 
               11/014,762 
               11/014,724 
               11/014,723 
               11/014,756 
               11/014,736 
               11/014,759 
             
             
               11/014,758 
               11/014,725 
               11/014,739 
               11/014,738 
               11/014,737 
               11/014,726 
               11/014,745 
             
             
               11/014,712 
               11/014,715 
               11/014,751 
               11/014,735 
               11/014,734 
               11/014,719 
               11/014,750 
             
             
               11/014,749 
               11/014,746 
               11/014,769 
               11/014,729 
               11/014,743 
               11/014,733 
               11/014,754 
             
             
               11/014,755 
               11/014,765 
               11/014,766 
               11/014,740 
               11/014,720 
               11/014,753 
               11/014,752 
             
             
               11/014,744 
               11/014,741 
               11/014,768 
               11/014,767 
               11/014,718 
               11/014,717 
               11/014,716 
             
             
               11/014,732 
               11/014,742 
               11/097,268 
               11/097,185 
               11/097,184 
               10/728,804 
               10/728,952 
             
             
               10/728,806 
               10/728,834 
               10/728,790 
               10/728,884 
               10/728,970 
               10/728,784 
               10/728,783 
             
             
               10/728,925 
               10/728,842 
               10/728,803 
               10/728,780 
               10/728,779 
               10/773,189 
               10/773,204 
             
             
               10/773,198 
               10/773,199 
               10/773,190 
               10/773,201 
               10/773,191 
               10/773,183 
               10/773,195 
             
             
               10/773,196 
               10/773,186 
               10/773,200 
               10/773,185 
               10/773,192 
               10/773,197 
               10/773,203 
             
             
               10/773,187 
               10/773,202 
               10/773,188 
               10/773,194 
               10/773,193 
               10/773,184 
               11/008,118 
             
             
               11/060,751 
               11/060,805 
               11/188,017 
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               6,406,129 
               6,505,916 
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               10/296,434 
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               10/683,064 
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   BACKGROUND OF THE INVENTION 
   The assignee has developed mobile or cellular telephones, Personal Data Assistants (PDAs) and other mobile telecommunication devices, with the ability to print hard copies of content, such as images or information stored or accessed by the device, (see for example, U.S. Pat. No. 6,405,055, filed on Nov. 9, 1999). Likewise, the assignee has also designed digital cameras with the ability to print captured images with an in-built printer (see for example, U.S. Pat. No. 6,750,901, filed on Jul. 10, 1998). As the prevalence of mobile telecommunications devices increases, the functionality of these devices is further enhanced by the ability to print hard copies. 
   As these devices are portable, they should be compact for user convenience. Accordingly, any printer incorporated into the device needs to maintain a small form factor. Also, the additional load on the battery should be relatively small. Furthermore, the consumables (such as ink, paper, etc.) should be relatively inexpensive and simple to replenish. It is these factors that strongly influence the commercial success or otherwise of products of this type. 
   The assignee of the present invention has also developed the Netpage system for enabling interaction with computer software using a printed interface and a proprietary stylus-shaped sensing device. As described in detail in U.S. Pat. No. 6,792,165, filed on Nov. 25, 2000 and U.S patent application Ser. No. 10/778,056, filed on Feb. 17, 2004, a Netpage pen captures, identifies and decodes tags of coded data printed onto a surface such as a page. In a preferred Netpage implementation, each tag encodes a position and an identity of the document. By decoding at least one of the tags and transmitting the position (or a refined version of the position, representing a higher resolution position of the pen) and identity referred to by the decoded tag, a remote computer can determine an action to perform. Such actions can include, for example, causing information to be saved remotely for subsequent retrieval, downloading of a webpage for printing or display via a computer, bill payment or even the performance of handwriting recognition based on a series of locations of the Netpage pen relative to the surface. 
   When printing a Netpage, a printer in a mobile telecommunications device can print the Netpage tags simultaneously with visible user information. The association between the tags and information can already exist on a remote Netpage server, such as where the printer is printing a fully rendered page (including tags) provided by the Netpage server or another computer. Alternatively, the mobile telecommunications device can generate the tags (or source them remotely) and define an association between the tags and user information. The association is then recorded in the remote Netpage server. 
   A problem with these options is that they require the mobile telecommunications device to include Netpage tag printing capabilities. This requires an additional row of print nozzles in the printhead, and reduces the amounts of ink that can be stored for non-tag use. Whilst this is less of an issue with large, mains-powered printers, it can be an issue in small form-factor articles such as mobile telecommunications devices. Alternatively, the mobile telecommunications device can be configured to print on print media that is pre-printed with Netpage tags. That way the printer need only print the user information and record an association between the visible information and the pre-printed tags. 
   It is desirable to provide functional applications making use of the mobile telecommunications device. Such applications can include, for example, mobile printing applications, linking, capturing and/or printing generic or specific objects to a print medium, and many other applications providing functionality to the mobile telecommunications device and various uses of types of print media. 
   SUMMARY OF THE INVENTION 
   In one particular, but non-limiting, aspect, an M-Print device is a mobile device such as a telephone or PDA which incorporates a printer. Paper is either manually presented or auto-fed from a cartridge, depending on device form factor. The printer may or may not print tags, for example infrared tags, and the printer or a sensor detects tags printed, for example pre-printed, onto blank media. The paper path either includes a tag reader, or it includes a simpler sensor for reading a linear data track on the card. The data track can encode the same identifier as the tags. Reading the identifier allows the M-Print device to associate the card&#39;s graphic and/or interactive content with the identifier. This allows subsequent interactions with the card to be properly interpreted. The graphic and/or interactive content is stored on a network-based server, indexed by the identifier. 
   It should be noted that the media identifier (i.e. print media identifier) may correspond to a range of 2D coordinates without an explicit single media identifier. Hence, reference to the media identifier is to be read as a reference to an explicit or defined one or more media identifiers, or, as a reference to a range of 2D coordinates. 
   The device also optionally incorporates a pointer. The pointer may be used to click on a hyperlink, but generally doesn&#39;t operate at a sufficiently high rate to capture motion. Alternatively, the telephone may incorporate a fully-functional Netpage-type pen. Even when the M-Print device doesn&#39;t incorporate a pointer, the user can interact with printed cards by feeding them through the paper path. The data track reader or tag reader in the paper path extracts the identifier, which allows the device to identify the graphic and/or interactive content of the card, and object(s) linked to the card. Not all M-Print cards have to be produced by an M-Print device. For example, pre-printed M-Print cards of a collectible or promotional nature may be included in cereal packets or magazines. And even blank media may bear advertising on the reverse side. Not all M-Print cards have to be interacted with via a pointer in an M-Print device. They can be interacted with via any device, or another scanning device altogether which can read the data track or an application-specific printed barcode. 
   An M-Print card acts as a token for the graphic and/or interactive content of the card, including any objects linked to the card. A user can easily obtain the original digital content of the card by clicking on the card or ‘virtually scanning’ the card through the paper path. For example, a photo acts as a token for the original digital image, and a business card acts as a token for the contact details linked to the card. By acting as a token for its own content, a card allows a user to obtain a perfect re-print. In addition to the identifier, the data track and the tags encode a digital signature which allows the card to be authenticated. This has two purposes. Firstly, it allows a blank card to be authenticated during printing to prevent the use of non-sanctioned blanks. Secondly, it allows a card to be authenticated when used as a token, to prevent fraudulent access to the content of the card or objects linked to the card. 
   Various applications are possible using aspects, components or features of the mobile telecommunications device and associated coded print medium. Such applications can include mobile printing applications, linking, capturing and/or printing generic or specific objects to a print medium, and many other applications providing practical uses for the coded print medium and/or the mobile telecommunications device. Various particular applications are herein described. 
   In a first aspect the present invention provides method of linking an object to a print medium, comprising the step of:
         submitting a request to associate the object with a print media identifier of the print medium, submission of the request facilitating identification of the object and the print media identifier;   wherein, the association of the object and the print media identifier is recorded in a database, the object being retrievable from the database using the print media identifier.       

   Optionally the print medium is supplied to a user with at least one pre-linked object. 
   Optionally submission of the request is effected using a sensor module associated with a mobile telecommunications device. 
   Optionally identification of the object occurs by the mobile telecommunications device retrieving the object. 
   Optionally identification of the object occurs by the mobile telecommunications device capturing the object as an image using a camera. 
   In a further aspect there is provided a method, further including the steps of:
         receiving the print medium in a media feed path of the mobile telecommunications device; and,   reading the print media identifier from the print medium using the sensor module of the mobile telecommunications device.       

   Optionally the sensor module is at least one of: integrated with the mobile telecommunications device; and external to the mobile telecommunications device. 
   Optionally the print medium is provided with first coded data in a first data format, the first coded data encoding first information. 
   Optionally the first information includes the print media identifier. 
   Optionally the first format is a linear pattern. 
   Optionally the print medium is provided with second coded data in a second data format, the second coded data encoding second information. 
   Optionally the second information is indicative of a two-dimensional coordinate grid. 
   Optionally the second information includes the print media identifier. 
   Optionally the second information is indicative of regions of the print medium surface. 
   Optionally a printer module of a mobile telecommunications device prints the second coded data on the print medium. 
   Optionally the second coded data is pre-printed on the print medium. 
   Optionally the object is associated with a region of the print medium using the second coded data. 
   Optionally the printer module prints the first coded data on the print medium. 
   Optionally the object is associated with a form, as a particular field of a form or a particular instance of a form. 
   Optionally the object can be associated with a second print media identifier. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     An example embodiment of the present invention should become apparent from the following description, which is given by way of example only, of a preferred but non-limiting embodiment, described in connection with the accompanying figures. 
       FIG. 1  illustrates an example High Level Architecture; 
       FIG. 2  illustrates example M-Doc Retriever Components; 
       FIG. 3  illustrates an example Nugget Generation Service; 
       FIG. 4  illustrates an example Player; 
       FIG. 5  illustrates an example PlayRequest; 
       FIG. 6  illustrates example Values, Types and Categories; 
       FIG. 7  illustrates an example interactive business card; 
       FIG. 8  illustrates an example Player Sequence; 
       FIG. 9  illustrates an example RequestRouter and related classes; 
       FIG. 10  illustrates an example UserRequestRouter; 
       FIG. 11  illustrates a typical arrangement of routers and player agents in a Netpage system; 
       FIG. 12  illustrates example Capability and Request Propagation; 
       FIG. 13  illustrates an example Capability Aggregation; 
       FIG. 14  illustrates an example Capability Transformation; 
       FIG. 15  illustrates example PlayerProfiles; 
       FIG. 16  illustrates an example Printed Interface for selecting the current player profile; 
       FIG. 17  illustrates example PlayRequests embedded in an interactive document; 
       FIG. 18  illustrates an example Request Routing; 
       FIG. 19  illustrates an example Synchronous Messaging Sequence Diagram; 
       FIG. 20  illustrates an example Asynchronous Messaging Communication Sequence; 
       FIG. 21  illustrates an example Streaming Messaging Sequence; 
       FIG. 22  illustrates an example Interactive Messaging Sequence; 
       FIG. 23  illustrates an example Hybrid Messaging Sequence; 
       FIG. 24  illustrates an example Player Session Sequence Diagram; 
       FIG. 25  illustrates an example Player Session Detailed Sequence Diagram; 
       FIG. 26  illustrates an example Desktop Player Deployment; 
       FIG. 27  illustrates an example Short-Range Thin Mobile Player Deployment; 
       FIG. 28  illustrates an example Long-Range Thin Mobile Player Deployment; 
       FIG. 29  illustrates an example Smart Mobile Player; 
       FIG. 30  illustrates an Object association being displayed in a physical Player Device; 
       FIG. 31  illustrates an Object association being displayed in the Explorer application; 
       FIG. 32  illustrates a Creation of an impression object association; 
       FIG. 33  illustrates an example Tagged Sticker; 
       FIG. 34  illustrates an example Reusable Sticker; 
       FIG. 35  illustrates an example Sticker with “Confirm Action”; 
       FIG. 36  illustrates an example Sticker with limited interactive areas to prevent accidental invocation of destructive operations; 
       FIG. 37  illustrates example Category Specific Stickers; 
       FIG. 38  illustrates an example Swipe based printed toolbar for creating impression associations; 
       FIG. 39  illustrates an example Swipe Based Sticker with Transparent Region; 
       FIG. 40  illustrates an example Swipe Based Sticker with Graphics over the Transparent Region; 
       FIG. 41  illustrates an example Impression Associations Object Model; 
       FIG. 42  illustrates example Field Associations in the Netpage Server; 
       FIG. 43  illustrates an example Object Association Sample Application; 
       FIG. 44  illustrates an example Underlying Form; 
       FIG. 45  illustrates an example Overlayed Form; 
       FIG. 46  illustrates an example Printed Contacts with Phone Numbers; 
       FIG. 47  illustrates an example State machine for basic clipboard interaction; 
       FIG. 48  illustrates an example interactive Netpage card with common operations; 
       FIG. 49  illustrates an example State machine for operation based clipboard; 
       FIG. 50  illustrates simultaneously supporting both object first and command first models; 
       FIG. 51  illustrates example Single use clipboard entries; 
       FIG. 52  illustrates an example Single-use clipboard with timeouts; 
       FIG. 53  illustrates an example Multi-use clipboard with timeouts; 
       FIG. 54  illustrates an example Interactive card for selecting a printer; 
       FIG. 55  illustrates example Field details of printer selection card; 
       FIG. 56  illustrates an example Netpage form containing various commands; 
       FIG. 57  illustrates an example Command form showing details of office printer field; 
       FIG. 58  illustrates an example SMS Based Downloadable Content Purchase; 
       FIG. 59  illustrates an example Netpage Play Sequence for Previewing a Ringtone; 
       FIG. 60  illustrates an example Using play requests to deliver the product; 
       FIG. 61  illustrates an example Using play requests to purchase the product, and traditional delivery; 
       FIG. 62  illustrates an example Hybrid approach using traditional delivery on the last hop to the handset; 
       FIG. 63  illustrates an example Load card; 
       FIG. 64  illustrates an example Validating an ID; 
       FIG. 65  illustrates an example High level printing sequence; 
       FIG. 66  illustrates an example High level sequence diagram for uploading from a mobile device; 
       FIG. 67  illustrates an example High level sequence diagram for downloading to a mobile device, using a SMS alert to trigger the download; 
       FIG. 68  illustrates an example Sequence fragment showing the processing of scanned ID; 
       FIG. 69  illustrates an example Local Photo Printing Sequence; 
       FIG. 70  illustrates an example Printing Uploads to a Photo Archive; 
       FIG. 71  illustrates an example Capturing a Netpage document via printing; 
       FIG. 72  illustrates an example Business Card; 
       FIG. 73  illustrates example Business Card Phone Number Fields; 
       FIG. 74  illustrates an example Business Card Fax Field; 
       FIG. 75  illustrates an example Business Card Web URL Field; 
       FIG. 76  illustrates example Business Card SMS and MMS Fields; 
       FIG. 77  illustrates an example Business Card Email Field; 
       FIG. 78  illustrates an example Street Address Field; 
       FIG. 79  illustrates an example Business Card Photo and Name Field; 
       FIG. 80  illustrates an example Business Card Identifier Field; 
       FIG. 81  illustrates an example Printed photo card; 
       FIG. 82  illustrates example Interactive fields for photo card; 
       FIG. 83  illustrates an example Scanning of an M-Print printout; 
       FIG. 84  illustrates an example Sequence diagram for generating Netpage clicks from a mobile device GUI; 
       FIG. 85  illustrates a schematic representation of the modular interaction in a printer/mobile phone; 
       FIG. 86  illustrates a schematic representation of the modular interaction in a tag sensor/mobile phone; 
       FIG. 87  illustrates a schematic representation of the modular interaction in a printer/tag sensor/mobile phone; 
       FIG. 88  is a more detailed schematic representation of the architecture within the mobile phone of  FIG. 87 ; 
       FIG. 89  is a more detailed schematic representation of the architecture within the mobile phone module of  FIG. 88 ; 
       FIG. 90  is a more detailed schematic representation of the architecture within the printer module of  FIG. 88 ; 
       FIG. 91  is a more detailed schematic representation of the architecture within the tag sensor module of  FIG. 88 ; 
       FIG. 92  is a schematic representation of the architecture within a tag decoder module for use instead of the tag sensor module of  FIG. 88 ; 
       FIG. 93  illustrates an exploded perspective view of a “candy bar” type mobile phone embodiment; 
       FIG. 94  illustrates a partially cut away front and bottom view of the embodiment shown in  FIG. 93 ; 
       FIG. 95  illustrates a partially cut away rear and bottom view of the embodiment shown in  FIG. 93 ; 
       FIG. 96  illustrates a front elevation of the embodiment shown in  FIG. 93  with a card being fed into the entry slot; 
       FIG. 97  illustrates a cross section view taken along line A-A of  FIG. 96 ; 
       FIG. 98  illustrates a cross section view taken along line A-A of  FIG. 96  with the card emerging from the media exit slot of the mobile phone; 
       FIG. 99  illustrates a lateral cross section through a print cartridge; 
       FIG. 100  illustrates the media coding on the card with separate clock and data tracks; 
       FIG. 101  illustrates a block diagram of an M-print system that uses media with separate clock and data tracks; 
       FIG. 102  illustrates a simplified circuit diagram for an optical encoder; 
       FIG. 103  illustrates a block diagram of the MoPEC with the clock and data inputs; 
       FIG. 104  illustrates a block diagram of the optional edge detector and page sync generator for the M-print system of  FIG. 101 ; 
       FIG. 105  illustrates a block diagram of a MoPEC that uses media with a pilot sequence in the data track to generate a page sync signal; 
       FIG. 106  illustrates a schematic representation of the position of the encoders along the media feed path. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The following modes, given by way of example only, are described in order to provide a more precise understanding of the subject matter of a preferred embodiment or embodiments. In the figures, incorporated to illustrate features of an example embodiment, like reference numerals are used to identify like parts throughout the figures. 
   1.0 Printing Internet Based Content Product Architecture 
   An example of a M-Print print media is the size of a business card. In general, documents or web based materials that have been designed for display on a desktop monitor or to be printed on A4 or Letter paper and may not print well on such sized media. If the content is reduced for the business card media then the content may be too small for easy reading. If multiple pages of media are used to print a page then the user is required to assemble the pages in the correct order before the printout is meaningful. To have presentable, effective content on a business card sized media the content should be specifically authored for that sized media. Described herein is a general mechanism to allow the authors and providers of web applications and web sites to make explicit use of the new media size, such as a business card. 
   The term “Mobile Document” or M-Doc is herein used to refer to documents specifically authored to be printed via M-Print. The format of a “Mobile Document” (i.e print medium) may vary, it can be pre-rendered and in a format ready to be sent directly to the printer, or it can be in a higher level format that requires rendering before printing. On some mobile devices it is not be possible to render the “Mobile Document” on the device, thus the “Mobile Document” is rendered before being sent to the mobile device. In regard of other mobile devices, the “Mobile Document” can be sent in the high level format and rendered on the mobile device. In general, to be able to render on the device the “Mobile Document” format is provided in an encapsulated format that contains the data necessary to render the M-Doc. Thus, by providing the M-Doc in an encapsulated format, the M-Doc does not necessarily have to rely on a particular font or bitmap being available on the mobile device (i.e. mobile telecommunications device). 
   A common usage of a “Mobile Document” is for the author of a web page to summarise contents of the web-page in a “Mobile Document”, which will herein be referred to as a “Nugget”, and to provide a link on the page for users to print the nugget. When the web page is static HTML the content of the nugget can also be static. If the web page is dynamic HTML then it is likely the content of the nugget may also have to be dynamically created. 
   Current 2.5 G mobile data networks have low bandwidth, high latency, and are expensive to transfer data over. The emerging 3 G networks improve the bandwidth and latency but are still expensive to transfer data over. Mobile carriers tend to subsidise some of the data transfer mechanisms to encourage use, so it is possible to have a situation where it is significantly cheaper to send data via an MMS than it is to transfer it via a HTTP request over the same network. For this reason the proposed architecture supports multiple ways of delivering an M-Doc to a mobile device. The architecture is also designed to minimise the number of requests that need to be made from the device to retrieve a M-Doc and to also to minimise the amount of data that needs to be transferred to the device to transmit an M-Doc. 
   There are three messaging services in common use in the mobile networks at the moment: SMS (Short Message Service), EMS (Enhanced Message Service and MMS) (Multimedia Message Service). SMS is generally designed for sending text only messages up to 160 characters long. EMS is an enhanced version of SMS consisting of several SMS messages clustered together. This mechanism is used to deliver ring tones, etc to handsets. Both SMS and EMS are implemented using existing mechanisms in the GSM or CDMA networks and do not require IP based bearers such as GPRS. MMS provides the ability to send a mixture of multimedia formats such as images, sound and movies along with a definition of how to use these multimedia formats using the Synchronized Multimedia Integration Language, SMIL. MMS does not have any theoretical size limits. MMS is implemented on top of IP bearers and requires GPRS or one the 3G equivalents to be deployed. Since MMS uses IP bearers it is not able to self-transfer or “push” itself out to a handset, instead it uses SMS to alert the user to the fact that an MMS message is waiting in the network for the user to retrieve, so it requires a “push” and “pull” to retrieve the message, whereas SMS requires a single “push” and EMS is delivered by multiple “pushes”. 
   1.1 High Level Architecture 
   Referring to  FIG. 1 , a M-Doc  500  residing in the network  501  generally requires delivery to the mobile device  100  before it can be printed. There are two ways in which a request to retrieve and print an M-Doc  500  can originate:
         1—direct user action, typically clicking on a link on a web page; or   2—the arrival of an SMS or MMS containing a M-Doc reference  507  or an M-Doc  500  itself.       

   A M-Doc Retriever  502  is a component responsible for fetching an M-Doc  500 . The M-Doc  500  is then passed to the M-Doc Printing Service  503  and printed. The following sections explain each of these major components and their inputs and outputs in more detail. 
   1.1.1 Web/WAP Browser 
   The Web Browser  504  is a third party application available on the mobile device  100 . It is used by the user to browse web pages. A web site that supports printing M-Docs  500  includes web pages that contain M-Doc Reference links. When the user clicks on a M-Doc Reference link, a M-Doc  500  reference is returned to the browser  504 . The M-Doc reference  507  can be handled by the browser  504  in a number of ways dependent upon the operating system running on the mobile device  100 . 
   It is also possible for the M-Doc Retriever  502  to be activated directly by passing the M-Doc Retriever  502  a web page reference. This triggers a Nugget Creation service  506  to generate a Nugget for the website which the web page reference is associated with. The ability to generate a meaningful Nugget for a website depends on the content of the website. 
   1.1.2 M-Doc Retriever 
   The M-Doc retriever  502  is activated by the arrival of M-Doc reference  507  to the device. 
   Referring to  FIG. 2 , the M-Doc Retriever  502  is responsible for taking a M-Doc Reference  507  and resolving it to an M-Doc  500  to be passed onto the M-Doc Printing Service  503 . There are a number of ways that a M-Doc Reference  507  can be supplied to the M-Doc Retriever  502 :
         1. MIME type recogniser  508 —This can be activated either by clicking on a link in a web page that causes an “HTTP Get” of an object whose MIME type is an M-Doc reference  507 . Or it can be activated by the arrival on the mobile device of an Obex transfer  511 .   2. Message Monitor  509 —This is a component that monitors the Inbox of the Messaging Service on the mobile device. When it receives a message from any source that contains an M-Doc reference  507 , the Message Monitor  504  passes the M-Doc reference  507  onto the M-Doc Retriever  502 .   3. Web browser plugin  510 —This is triggered by explicit scripting code in a web page being browsed on a web browser  504 . When the Web browser plugin is activated, it is passed a M-Doc reference  507  which is passed onto the M-Doc Retriever  502 .       

   The M-Doc Retriever  502  receives the M-Doc Reference  507  which is in the format of a URI (Uniform Resource Identifier). The M-Doc Retriever  502  appends device specific information to URI and is dispatched via an HTTP request to the M-Doc Retrieval Service  512  running on the device. Device specific information that is appended to the URI is dependent upon how the system has been deployed and the capabilities of the device. 
   If a Mobile Device Capability Service  513  is deployed in the network  501  then the device specific information appended only requires identification the handset, via IMEI. If the Mobile Device Capability Service  513  is not deployed in the network  501  then the device  100  is required to append information relating to the printer  4 , the formats of M-Doc&#39;s  500  the device  100  is capable of printing and the preferred delivery method. The printer information required is deployment specific. If the renderer is able to look up the printer characteristics based on the handset or a printer version number then only those need to be provided, but if not, then information relating the printers resolution and colour space parameters are required. 
   The M-Doc URI that is supplied by the application is used to retrieve the M-Doc  500 . This URI contains information needed to retrieve or generate the M-Doc  500  from the application  514 . If the format of the returned M-Doc  500  matches the format(s) the device  100  is capable of printing, then the document  500  is delivered to the device  100 . If there is an unsuccessful match, the M-Doc  500  is rendered. This is performed by passing the document  500  to the rendering service  515  along with the printer information. The rendering service returns the document in a pre-rendered format which can be printed by a mobile device  100  containing a printer  4 . 
   The way in which the M-Doc  500  is delivered back to the M-Doc retriever  502  can also vary. It may be returned in the reply to the original HTTP request or it may be sent via an MMS or e-mail. These later two cases are most likely to be used in an environment where the pricing policy of a carrier encourages MMS or email use over general web browsing. The preferred delivery method may be included in the retrieval request or it may be looked up via the Mobile Device Capability Service  513 . 
   The Rendering Service  515  may also be used directly by application writers who want to provide pre-rendered M-Doc&#39;s within their application. In this case the Rendering Service  515  is accessed via SOAP (Simple Object Access Protocol) as a web service, providing the M-Doc  500  in its authored format and obtaining the pre-rendered print format document and a thumbnail image for use in a GUI  516  of the application  514  running on the device  100 . 
   When an MMS  517  is sent to the mobile device  100 , the MMS  517  is stored in the mobile network at a MMS Message Centre  518  and an SMS is sent to the device to alert the user an MMS  517  is waiting to be fetched. With a modification this notification mechanism can be used to deliver an M-Doc  500  to a phone  100 . The SMS notification can contain both an M-Doc reference  507  and an MMS notification. The request to fetch the MMS from the Message Centre  518  can be enhanced with the M-Doc reference  509 , allowing the Message Centre  518  to contact the M-Doc Retrieval Service  512  to retrieve the M-Doc  500  in the body of the MMS  517 . This service is called an M-Doc MMS service. 
   Any email, MMS, Obex or web page may contain a direct M-Doc  500  rather than an M-Doc Reference  507 . In this case the M-Doc  500  is passed directly onto the M-Doc Printing Service  503 . Unless the sender of the message knows the capability of the handset receiving the M-Doc  500 , the M-Doc  500  may not be able to be rendered appropriately, hence the M-Doc Reference  507  approach is preferred, but in some cases, such as a subscription, the sender may know the capabilities of the handset and hence be able to by-pass the M-Doc Retrieval process and deliver the M-Doc  500  directly. 
   1.1.3 M-Doc Printing Service 
   The M-Doc Printing Service  503  prints the document  500  to the printer  4  in the mobile device  100 . M-Doc&#39;s  500  may have different document formats, but the M-Doc Retriever stage ensures that it retrieves an M-Doc  500  in a format that can be printed by the mobile device  100  without any further network interactions. 
   1.1.4 Nugget Production 
   A Nugget is the distillation of the content of a web page onto an M-Print sized printout. In general this not only involves reducing the web layout so that the content fits onto the M-Print printout. The process also involves selecting the key pieces of information on the web page and explicitly composing an M-Doc  500  that presents the information appropriately. Nugget support can be provided in two ways:
         1. As part of the design of the application  514     2. By a nugget generating service  519 .       

   Providing nugget support as part of the design of web application  514  requires the author of the web interface to provide a link to a nugget on the web page. Depending on the nature of the web content the nugget could either be statically authored along with the page or it could be dynamically authored based on the dynamic content on the web page. 
   For web sites that do not support Nuggets as part of the interface, nuggets can be generated by a nugget generation service  519 . 
   Referring to  FIG. 3 , the Nugget Generation Service  519  is activated when a special form of a M-Doc Reference  507  is passed to the M-Doc Retriever  502  on the mobile device  100 , which references a web page rather than an M-Doc. The Nugget Retrieval Service detects this and passes the request onto the Nugget Creation Service  519 . 
   The Nugget Creation Service  519  generates a nugget for the supplied web page in one of two ways:
         1. If the supplied web page comes from an explicitly supported web application, it passes the web page onto the nugget generator for that web application. Common web applications such as: Google, e-bay, Yahoo, Wikipedia and Amazon could be supported.   2. If the web page is not from a supported application, then the contents is scaled to fit into an M-Doc  500 .       

   The nugget generator for supported applications include knowledge of the structure of the web page and the main purpose of the web application, and thus be able to extract information from the key fields and present that in a nugget. For example:
         A Google web page could be distilled to a nugget by showing the: search criteria; the top ten hits; how many other hits where returned.   An Amazon web page could be distilled to showing the contents of the shopping cart.   A Wikipedia web page could be distilled to the term and the definition.
 
1.2 Applications
       

   This section discusses some applications of Internet Based M-Document printing architecture. Any M-Doc  500  can be Netpage enabled. 
   1.2.1 Daily Subscription Services 
   Many people buy the daily newspapers to access a few small sections of the paper, eg. puzzles, crosswords or cartoons. Using M-Doc printing it is possible for a user to browse online to the content and then request a printout of the content of their choice. To avoid having to browse each day, a subscription service that “pushes” the user&#39;s desired sections out to them each day can be set up. The service could use: SMS, MMS or e-mail to “push” the M-Doc References out to the mobile device. The user can then print then content of the subscription when required. 
   Some of the sections of a newspaper that would suit this form of distribution are:
         Crossword puzzles: Crossword grid on one sheet; clues on another.   Number puzzles, eg. Sudoku   Jokes   Cartoons   Local Weather
 
1.2.2 Navigation and Location Based Services
       

   Web services such as “WhereIs” (www.whereis.com) provide both the ability to get a list of directions to go from one location to another and/or a map. Using a mobile device&#39;s browser  504  the user can enter the destination and their current location and then have the map and directions delivered as an M-Doc  500  to be printed. 
   This gives a more convenient presentation of the map and directions to refer to while driving. Also in many regions in the world it is illegal to look at a mobile phone while driving, but it is not illegal to consult a map or written directions. 
   Mobile devices  100  that support location services are able to supply their location automatically. In this case it is only necessary to specify the destination to receive a map and/or a set of directions to print. 
   As well as assisting navigation, location based services can be used to present of list of possible destinations. For example:
         A service that prints out the list of restaurants within walking distance;   Directions to the closest Service Station (or any type of shop);   Directions to the closest public transport stop.
 
1.2.3 Company Business Cards
       

   Corporate websites often promote a company&#39;s public image, this can be extended by providing the ability to print a “Company Business Card” that gives the general information about the company and its general contact details. As well as a general “Company Business Card”, individual departments could easily have their own business cards, eg. the Service Department contact details. 
   Web sites for companies normally have a page dedicated to how to find them, that is, directions on how to get to their buildings from major transport hubs. These sites could easily include M-Documents  500  showing maps of:
         How to get to the company&#39;s premises   Where the closest parking is   Where the closest Hotel is   Directions on how to navigate from one building to another.
 
1.2.4 Discount Coupon/Voucher
       

   Discount coupons can be delivered by M-Documents  500 . These can be delivered via the web as part of an advertisement, either directly with the advertisement containing a link to a M-Document  500  or a coupon could be delivered to the mobile device as a reward for clicking through an advertisement to the companies web site. 
   A company could “push” out via SMS, MMS or e-mail vouchers to members of their loyalty scheme or just to the general public as a promotion. Another variation on this scheme is the ability to deliver a voucher or coupon to a user who enters a competition or votes on-line. For example, using an SMS to vote on a reality TV show could result in an MMS being returned with a coupon for a prize, or voting from a web site could return an M-Doc  500  with an advertisement and the possibility of a prize. 
   1.2.5 On-line Receipts 
   When performing on-line transactions from a mobile device  100  a receipt for the transaction can be returned via an M-Doc  500 . This gives a printout that can be filed with a user&#39;s other receipts. The receipts can contain bar codes and/or be Netpage enabled to allow the transaction to be recalled on-line on demand. Some example on-line transactions this could be used for are:
         Betting, the nugget can record: the selected options, the odds, the money wagered and the possible payouts;   Banking, the nugget can be similar to an EFTPOS receipt;   Purchasing, the nugget can be similar to a shop receipt;   Paying bills;   Taxi payment
 
1.2.6 Ticketing
       

   For tickets that do not require magnetic stripes it is possible to deliver them over-the-air at the time of purchase. This could included: Public transport tickets; Theme park ride tickets; Theatre tickets; Cinema tickets. 
   1.2.7 Web CAM Print 
   While viewing a web cam on your mobile device, a user can select print and have an M-Document  500  of the image at that time sent to the users phone. 
   1.2.8 On-line Gaming 
   On-line games can use Nuggets to provide additional information about the game. They can be used to provide: Cheat sheets; Maps; Character summaries; Brag cards, to demonstrate what level you have reached; Vouchers or Coupons as rewards for achievement. 
   2. Player Architecture 
   A Netpage Player  520  is a physical or virtual device capable of “playing” requests of various types. A play request  521  consists of three parts:
         1. The target  522 , which specifies which player  520  the request  521  should be played.   2. The operation  523 , which specifies the action to be performed.   3. A set of values  524 , which are supplied as parameters to the operation  523 .       

   Typically play requests  521  arise in response to user actions. For example, the user clicks on a tagged surface with a Netpage pointer, or interacts with an application that is in contact with the Netpage system. Play requests  521  can be used to provide a simple feedback mechanism (such as a request to display a text string to the user), or may be used to cause more sophisticated interactions with physical devices (such as setting the thermostat temperature on a home air conditioning system). 
   Individual players  520  can be associated with a user  525  as shown in  FIG. 4 . A user  525  may be associated with multiple players  520  each of which supports the playing of possibly overlapping sets of PlayRequests  521 . 
   It is likely that in many cases a single physical NetpagePlayer device  520  is shared between multiple users  525 . For example, a hi-fi audio system in a family room may be configured as an audio player for multiple members of the family. For the sake of brevity, this section focuses on cases where physical players are exclusively used by a single user, however, it will be appreciated that this section may be applied to multiple users. 
   Central to the NetpagePlayer  520  concept is the notion of a PlayRequest  521  which are objects that represent a request to perform an operation on some device. This sections describes various details related to PlayRequests  521 . 
   2.1 Structure of a PlayRequest 
   A PlayRequest (see  FIG. 5 ) consists of three parts, each of which is optional:
         1. An optional target  522  which specifies which Netpage player  520  the request  521  should be played,   2. An optional operation  523  which specifies the type of action to be performed on the target player  522 , and   3. An optional list of values  524  which are supplied as parameters to the operation  523 .       

   A play request  521  may either be fully or partially specified. Afully specified play request completely specifies all of the information (target, operation, and parameters) required to unambiguously deliver the request to the target  522  and to perform the desired operation  532 . A partially specified play request provides some indication of the request  521  to be played, but does not provide enough information in order for the play request  521  to be successfully delivered and played without further processing. 
   A target  522  may either fully or partially specify the target  522  of a play request  521 . A fully specified target completely identifies the physical player  520  on which the request  521  should be played. A partially specified target provides some indication of the desired target  522 , but does not provide enough information in order for the play request  521  to be delivered without further processing. An operation  523  can also be fully or partially specified. A Value  524  consists of a physical type  525  and associated data  526 . For example, the physical type  525  might be “image/jpeg” and the data  526  would be the binary image data. 
   2.2 Values and Types 
   A Value  524  represents an instance of some physical type  525 . Each Value  524  has an associated physical type  525  and zero or more associated type categories. The physical type identifies the structure of the data element of the Value  524 . A possible mechanism would be to use MIME types. For example, if the physical type  525  is image/jpeg then the data element would contain the binary data of an image in jpeg format. 
   Referring to  FIG. 6 , a Value is also optionally associated with one or more Categories  527 . A Category  527  is used to provide additional information about the value  524  which may allow it to be handled more sensibly by the system (i.e. to allow a PlayRequest to be better matched against the capabilities of candidate targets during request routing). As an example, an image value produced by a digital camera may have the physical type  525  image/jpeg, but may also be associated with a category  527  of “photo”, whereas an image value produced by a fax package might also have the physical type  525  image/jpeg, but could be associated with a category  527  of “facsimile” or with no category at all. 
   RequestRouters can take into account both the physical type  525  of a value  524  and the categories  527  to which it belongs when determining the most appropriate way to handle a request  521 . 
   2.3 Sample PlayRequests 
   To better demonstrate the PlayRequest concept, this section provides a number of sample PlayRequests  521 . A PlayRequest  521  can be viewed in tabular form as shown below by example in Table 1. 
   
     
       
             
             
             
           
         
             
               TABLE 1 
             
             
                 
             
           
           
             
               target 
               &lt;identification of the target of the request&gt; 
                 
             
             
               operation 
               &lt;the name of the operation to be performed&gt; 
             
             
               parameters 
               &lt;physical type and categories of parameter 1&gt; 
               &lt;value of 
             
             
                 
                 
               parameter 1&gt; 
             
             
                 
               . . . 
               . . . 
             
             
                 
               &lt;physical type and categories of parameter n&gt; 
               &lt;value of 
             
             
                 
                 
               parameter n&gt; 
             
             
                 
             
           
        
       
     
   
   Firstly, the Request  1  shows a fully specified PlayRequest  521  for dialling a number on a specific mobile phone. 
   
     
       
             
           
             
             
             
             
           
         
             
                 
             
             
               Request 1 
             
             
                 
             
           
           
             
                 
             
           
        
         
             
                 
               target 
               mobile-phone-xyz56474238 
                 
             
             
                 
               operation 
               dial 
             
             
                 
               parameters 
               phone-number 
               “555 6754” 
             
             
                 
                 
             
           
        
       
     
   
   The target field  522  is fully specified and indicates that the request  521  is to be performed on the device  520  identified by the name/address “mobile-phone-xyz56474238”. Note that for simplicity, simple text strings to indicate the address of each physical target  522 . The play request  521  contains an operation of “dial” which is understood by the mobile phone&#39;s NetpagePlayer  520 . The request  521  also includes a phone number which is a required parameter  528  to the “dial” operation  523 . 
   As shown below, Request  2  is only partially specified due to only containing a partially specified target  522 . The target  522  specifies that the request  521  should be played on a mobile phone, but does not specify which mobile phone. 
   
     
       
             
           
             
             
             
             
           
         
             
                 
             
             
               Request 2 
             
             
                 
             
           
           
             
                 
             
           
        
         
             
                 
               target 
               mobile phone 
                 
             
             
                 
               operation 
               dial 
             
             
                 
               parameters 
               phone-number 
               “555 6754” 
             
             
                 
                 
             
           
        
       
     
   
   Request  3  shown below is also only partially specified. In this case, the target  522  has been completely left out. Although only being partially specified, the request  521  has a definite meaning: “dial the phone number 555 6754”. The device to be used to dial the number is still to be determined. 
   
     
       
             
           
             
             
             
             
           
         
             
                 
             
             
               Request 3 
             
             
                 
             
           
           
             
                 
             
           
        
         
             
                 
               target 
                 
                 
             
             
                 
               operation 
               dial 
             
             
                 
               parameters 
               phone-number 
               “555 6754” 
             
             
                 
                 
             
           
        
       
     
   
   Request  4  is even less fully specified that Request  3 . Request  4  simply contains the phone number “555 6754”. The operation to be performed with the number and the device to handle the request (the target) is still to be determined and the device to handle the request (the target) is still to be determined. 
   
     
       
             
           
             
             
             
             
           
         
             
                 
             
             
               Request 4 
             
             
                 
             
           
           
             
                 
             
           
        
         
             
                 
               target 
                 
                 
             
             
                 
               operation 
             
             
                 
               parameters 
               phone-number 
               “555 6754” 
             
             
                 
                 
             
           
        
       
     
   
   Request  5  contains a fully specified target  522 , but does not specify an operation  523 . Thus, the target of the request  521  is known, but what the target  522  is to do with the request (the operation) is still to be determined. 
   
     
       
             
           
             
             
             
             
           
         
             
                 
             
             
               Request 5 
             
             
                 
             
           
           
             
                 
             
           
        
         
             
                 
               target 
               mobile-phone-xyz56474238 
                 
             
             
                 
               operation 
             
             
                 
               parameters 
               phone-number 
               “555 6754” 
             
             
                 
                 
             
           
        
       
     
   
   Request  6  can be used to send a simple text message to the user. The target  522  is not specified, so the request means display the following message on whichever player is the most appropriate at the current time. 
                                             Request 6                                    target                   operation   display           parameters   text   “Temperature in Sydney is 28° C.”                        
2.4 Invocation of PlayRequests
 
   Play requests  521  can arise in one of two ways:
         1. The user interacts with a printed Netpage form that has been authored to include invocations of play requests  521 .   2. An arbitrary application sends a play request  521  to a Netpage Server  529 .       

   These are discussed in the following sections. 
   2.4.1 Authored PlayRequests 
   PlayRequests  521  can be authored directly into a printed Netpage document.  FIG. 7  provides an example of an interactive business card  530 . The business card  530  contains interactive elements  531  that can be triggered by clicking on them with a Netpage pointer. Each interactive element causes a PlayRequest  521  to be invoked. The Netpage Server  529  then arranges for the request  521  to be played by routing it to the appropriate player device  520 . 
   For example, referring to  FIG. 7 , consider a user with a Netpage-enabled mobile phone device  100  with a built-in Netpage pointer. The user clicks on the mobile phone icon  532  on the business card  530  which causes the PlayRequest  521  to be triggered. The server  529  routes the play request  521  to the user&#39;s mobile phone  100  and upon receiving the request  521 , the mobile phone  100  commences dialling the required number. 
   2.4.2 Application Invoked PlayRequests 
     FIG. 8  shows a typical example of an application invoked PlayRequest  521 . The steps are as follows:
         1. A Netpage pen  533  transmits a digital ink stroke  534  to the Netpage Server  529 .   2. The stroke  534  is determined to be a request  521  to submit a Netpage form for processing.   3. The form is submitted to the corresponding Application  535 .   4. As part of the form submission processing, the application  535  requests that a play request  521  be played by a Netpage Player  520  associated with the user  525  who made the submission.   5. The Server  529  determines the target device  522  and relays the play request  521  to that device  522 .
 
2.5 Player Devices
       
   Netpage Player instances can be deployed on various Player devices (platforms). Individual players support some subset of the full range of PlayRequests  521  supported by Netpage. Table 2 shows some examples of Netpage Player Devices. 
                             TABLE 2                   Example Netpage Player Devices            Player Device   Comments               Desktop Player   This device is a powerful computing unit usually with fixed network connectivity. A       585   desktop player is capable of playing a wide range of PlayRequests (e.g. audio, video,           image, html, etc). The player can interact with various external software/hardware           components running on the device.       Thin Mobile   This device is a mobile unit with limited computing power such as web-enabled or       Player   low-end mobile phones.       587   The thin player running on such mobile device is capable of playing various           PlayRequests by utilizing the capabilities of the device. Examples include sending           SMS objects, dialling phone number objects, etc.           Due to the processing limitations of the device, a remote server (Netpage and           Application Server) processes the input strokes/clicks and provides the objects to the           player.       Smart Mobile   This device is a mobile unit with more computing and storage capabilities, such as a       Player   high-end smart mobile phone or a PDA.       588   Such device is capable of enabling most of the Netpage functionality by running a           Micro edition of the Netpage Server locally.           In such an environment, the player can receive PlayRequests from the local server           (running on the device) and no on-line connectivity to a remote server peer would be           necessarily required at the time of playing.       Embedded   An embedded player is a custom device that is built for a specific application.       Player   Examples of such players are Digital Camera, capable of playing (i.e. showing) images           and possibly video; or Audio Player, capable of playing audio. The Netpage player is           either built into the device or as a detachable unit.               Note that while some of the devices mentioned in Table 2 are also capable of recording/capturing objects (e.g. a digital camera of a mobile phone is capable of capturing images), access to such captured data is not accessible via the Netpage Player concept, but can be accessed via a Netpage Clipboard, which will be discussed in more detail.            
2.6 Request Processing
 
   This sections describes how PlayRequest objects  521  are processed throughout the Netpage system. The processing of requests includes two operations:
         1. The routing of requests  521  from one NetpagePlayer  520  to another.   2. The transformation of PlayRequests  521  (for example to change a partially specified request more specified) as they are being routed.
 
2.6.1 Request Routing
       

   A play request  521  is routed from source to the eventual destination via one or more intermediary RequestRouters  536  as shown in  FIG. 9 . RequestRouters  536  implement the NetpagePlayer interface, and are responsible for routing each PlayRequest  521  they receive to an appropriate target NetpagePlayer  520 . Each RequestRouter  536  maintains a set of potential targets  538 . Eventually a PlayRequest  521  arrives at a PlayerAgent  537  which is responsible for actually performing the play request  521 . 
   All PlayRequests  521  from (or on behalf of) a user  525  are initially handled by a RequestRouter  536  inside the Netpage Server  529 . This router is called the UserRequestRouter  539  (see  FIG. 10 ). Typically the UserRequestRouter  539  forwards requests to a RequestRouter  536  residing on a physical device, although such forwarding may pass through an arbitrary number of intermediary RequestRouters  536  along the way. Device based RequestRouters  536  are responsible for routing requests  521  to the various player agents  537  running on the device. 
   The typical scenario is shown in  FIG. 11 . The UserRequestRouter  539  has a set of potential targets  538  which are all RequestRouters  536  residing on physical devices. Each device&#39;s RequestRouter  536  then has a set of potential PlayerAgent targets. The PlayerAgents are the NetpagePlayers  520  that actually play requests  521 . 
   2.6.2 Request Transformation 
   Each RequestRouter  536  can optionally transform the PlayRequest  521  it receives before passing it on to a subsequent NetpagePlayer  520 . The transformation typically produces a more fully specified version of the supplied PlayRequest  521 , but may also produce a completely new PlayRequest  521  with no fields in common with the source PlayRequest  521 . 
   2.6.3 Player Capabilities 
   Different players have different capabilities. That is, each player is capable of playing a different set of PlayRequests  521 . The capabilities of a NetpagePlayer  520  are specified in a CapabilitySpecification  540 . The capabilities  541  of each child player are taken into account by RequestRouters  536  when handling PlayRequests  521 . The capabilities  541  of different players may overlap, potentially resulting in ambiguous PlayRequests  521 . Such ambiguities are resolved by RequestRouters using methods described in further detail below. 
   The CapabilitySpecification  540  is not limited to simply specifying which operations  523  can be performed on which value types  524 . It may also specify finer grained details. For a specific PlayRequest  521  the CapabilitySpecification  540  might specify that it can only handle a subset of possible values. For example, a player  520  that supports the playing of audio objects could place a limitation on the size of audio objects supported. 
   2.6.3.1 Capability and Request Propagation 
   As shown in  FIG. 12 , a PlayerAgent  537  advertises its capabilities  541  to its parent RequestRouter  542  which in turn propagates the aggregation of its children&#39;s capabilities  544  to its parent RequestRouter  543 . Eventually the propagation reaches the UserRequestRouter  539  which then has an overall view of the capabilities  545  of all of the players at its disposal. PlayRequest propagation moves in the opposite direction. Requests  521  start at the UserRequestRouter which determines the most appropriate child to which the request should be sent. The (possibly transformed) request is sent to the selected child which in turn propagates the request to one of its children. Eventually the request reaches a PlayerAgent  537  which is responsible for actually playing the request. 
   2.6.3.2 Capability Aggregation and Transformation 
   As a RequestRouter propagates player capabilities ( 541 ,  544 ,  545 ) to its parent RequestRouter  536 , it may perform capability aggregation and transformation. Capability Aggregation is where the router  536  combines the capabilities of its children into a single capability specification  548 . Capability Transformation is where the router  536  modifies the advertised capabilities of its children due to capabilities (or perhaps limitations) of the router itself. 
     FIG. 13  provides an example of a simple capability aggregation. The router has two children  550 ,  551 , the first child  550  of which advertises the capability to display jpeg images, the second child advertises the capability  553  to display plain text. The router  536  then aggregates the child capabilities  552 ,  553  into a single capability specification  540  which is capable of displaying both jpeg images and plain text. 
     FIG. 14  provides an example of a capability transformation. The PlayerAgent  537  advertises its capability  555  to display image/jpegs. The RequestRouter  536  has access to an image converter  559  that can convert images in png format to jpeg format. As such, the capability specification  555  is transformed before propagation into a capability specification  556  that includes the ability to display files in png format as well as in jpeg format. 
   2.6.4 Dynamic Capabilities 
   The capabilities advertised by a particular NetpagePlayer  520  can change over time. For example:
         1. Additional hardware or software can be installed/removed to/from a device, enabling the player to support more/less PlayRequests  521 .   2. The maximum object size supported by a player may change depending on the spare capacity in the player&#39;s memory.   3. A mobile player might be capable of receiving streaming media when it is connected to the network through a high-bandwidth network.   4. Common user interactions with the player (e.g. starting an application, changing a setting) can cause the player to advertise more or less capabilities.       

   Such changes in capabilities are to be communicated to the player&#39;s parent RequestRouter  536 , and potentially, but not always, to the parent&#39;s parent, and so on all the way to the UserRequestRouter  539 . 
   At the same time, as dynamic capability changes are being propagated, requests  521  are being routed in the opposite direction (as shown in  FIG. 12 ). This creates a race condition between capability propagation and request routing, such that by the time a request arrives at a RequestRouter  536 , either the request can no longer be handled by the player  520 , or the player  520  is no longer the most appropriate recipient for that request  521 . Either case may require that a request  521  be rejected by the player  520  (be it a router or an agent) and re-routed to the appropriate player  520 . 
   Additionally, dynamic propagation of capability changes could potentially cause an undesirable level of network traffic, harming overall system performance. 
   2.6.5 Request handling by the UserRequestRouter 
   As already discussed, all PlayRequests  521  presented to the NetpageServer  529  are handled by the UserRequestRouter  539 . The purpose of the UserRequestRouter  539  is twofold: (i) To determine the most appropriate child NetpagePlayer (the target  522 ) to which the request  521  should be routed; and (ii) To determine any required transformations to the request  521  that are necessary in order for the selected target  521  to be able to handle the request  521 . 
   In order to determine both of the above, the UserRequestRouter  539  takes into account the content of the PlayRequest  521  and the context within which it is handled. The context includes a large range of factors, including, but not limited to the following:
         1. The capabilities of each of the available children NetpagePlayers. Availability being partially determined by the user identity.   2. The current contents of the Netpage clipboard.   3. The originating source of the request (e.g. the Netpage pointer device which triggered the play request) and/or the route via which the request arrived.   4. The current player profile.   5. The current date and time.
 
2.6.6 Player Profiles
       

   It is possible that multiple players registered with a user support the same PlayRequests  521 . As a concrete example, consider the following scenario where a user has registered the following players. The user  525  has three registered players  520  all of which are capable of playing images:
         A camera phone for playing phone numbers, plain text, and images.   A digital camera for playing images.   A desktop application for playing plain text, html, images, video and audio.       

   Now consider the case where the UserRequestRouter  539  receives the following partially specified PlayRequest  521 : 
   
     
       
             
             
             
             
           
         
             
                 
                 
             
           
           
             
                 
               target 
                 
                 
             
             
                 
               operation 
               display 
             
             
                 
               parameters 
               image 
               contents of image 
             
             
                 
                 
             
           
        
       
     
   
   The request  521  could potentially be played on any of the devices  520  mentioned. As such, the request  521  is ambiguous. 
   PlayerProfiles  557  are one mechanism which can be used in order to allow the UserRequestRouter  539  to resolve  5  such ambiguities. A PlayerProfile  557  provides a (typically restricted) view of the set of players  520  available for a particular user  525  and the set of PlayRequests  521  that can be played on those players  520 . A user  525  may have multiple player profiles  525  indicating the various scenarios within which they use the Netpage system. At any point in time, one of these profiles  525  is set as the Current Profile  558  as shown in  FIG. 15 . 
   For example, a user might have the following profiles:
         An “office” profile that directs most player requests to their desktop PC.   A “home” profile that directs requests to various devices throughout the user&#39;s house.   A “mobile” profile that directs player requests to various portable devices (e.g. a smart phone).   A “car” profile that directs player requests to devices within the user&#39;s automobile.       

   A user can quickly change their current profile by a simple user action. For example, if in the office, the user could select the profile via a desktop GUI. Alternatively the user could use their Netpage pen/pointer to select a profile from a printed interface  559  such as that shown in  FIG. 16 . The system could also allow a user to specify regular scheduled times at which their current profile should switch. 
   2.6.7 An example request routine 
   Consider the interactive business card  530  shown in  FIG. 7 . The business card contains a number of interactive elements including the two fields  560 ,  561  highlighted in  FIG. 17 . Each of the fields  560 ,  561  is represented by a partially specified PlayRequest  562 ,  563 . Clicking on either field  560 ,  561  with a Netpage pointer causes the corresponding play request  562 ,  563  to be submitted to the Netpage Server  529  for processing. 
     FIG. 18  provides an example of how such a field might be routed. At step  564  we have the original play request as submitted to the server. At step  565  the UserRequestRouter interrogates the PlayRequest and the current context. and determines that the request should be routed to the user&#39;s mobile phone. As such it transforms the original PlayRequest to produce the request shown in step  566  and routes the play request to the RequestRouter on the mobile phone. At step  567  the mobile phone&#39;s RequestRouter checks whether the phone is in a quiescent state (i.e. no applications running). If so, it transforms the PlayRequest by setting the operation to “dial”, and is routed to the voice communications sub-system agent  568 . If, however, the SMS creation application is running, then the PlayRequest is transformed by setting the operation to “set-destination-number”, and it is routed to the running SMS creation application  569 . Lastly, if instead the Contacts application is running, then the PlayRequest is transformed by setting the operation to “add-contact”, and it is routed to the Contacts application  570 . 
   The end result is that the act of clicking on a telephone number on the business card can have very different results depending on the context within which it is applied. In this example, both the current context within the Netpage 
   Server  529  and the current context on the mobile phone were taken into account when processing the PlayRequest  521 . 
   2.7 Communicating with Players 
   Various communication methods are used between a Netpage Server  529 , intermediate gateways  570  and the Netpage client to enable the playing of PlayRequests  521  on the Player device  520 . Environmental factors such as the following affect the selected communication mechanism:
         Available network connectivity.   Type of player device being targeted.   Size and type of objects being transferred and the nature of the operation being played.       

   This section describes categories of messaging mechanisms. Note that in a single play scenario a combination of messaging methods can be used. 
   2.7.1 RPC (Synchronous) Messaging 
   Referring to  FIG. 19 , in an environment where a persistent connection can be maintained between the Netpage Server  529  and the Player  520 , the server  529  can send the play request  521  to the player, block till play a request is handled and a response  571  is returned. A Desktop Player in an active session can communicate to the server  529  using this method. 
   2.7.2 Notification (Asynchronous) Messaging 
   Referring to  FIG. 20 , notification messaging is used when the environment allows playing of an Object through an asynchronous play( ) request  521  initiated from the Netpage Server  529  to the Netpage Player  520 , delivering the object to be played. The server  529  may continue its activities and optionally receive a future response from the Player. The example of a notification based request delivery is when Netpage server pushes an image to a Netpage Player. 
   Depending on the underlying network infrastructure, a suitable protocol is used to push notifications to the Netpage Player, i.e. WAP push, SMS, etc. 
   2.7.3 Streaming 
   Referring to  FIG. 21 , for certain media types, it is preferable to be able to stream data to a player rather than transmitting the entire object before playing commences. The reasons are that:
         Large objects may take significant time to transmit in their entirety to the player. Streaming allows for playing to take place before the entire object has arrived at the player thereby reducing latency.   Target player devices may not have the capacity to hold the entire object. In that case, streaming is one option for playing the object on the device due to this limitation.   Unbounded objects such as live video can be transmitted by streaming.       

   Video and audio provide the most significant examples of types that are typically better suited to streaming. To enable the streaming Netpage Server would be involved in the player selection process and would then leave actual streaming up to the two parties. Otherwise the server is likely to be a bottleneck and a source of additional latency. 
   Player can perform read-ahead operations to buffer the data ahead of playing and avoid network delays and jitters which can affect the user&#39;s experience. 
   2.7.4 Interactive Messaging 
   Referring to  FIG. 22 , in some scenarios multiple user/pointer interactions with the Netpage Server  529  invoking multiple play requests is required to complete a user play experience. For instance consider a scenario where a user has a Netpage printout photo that he/she would like to send as a MMS message to a friend. One way of achieving this is by the user clicking on the friend&#39;s business card&#39;s MMS hyperlink. This action sends a play request to the player activating the MMS editor with the phone number to which the message is being sent. At this point user can choose to click on the photo to attach it to the MMS message. This results in the photo being sent as a second play request to the Player, wherein the photo is attached to the MMS content. The state of the player  520  allows chaining multiple play requests  521  to complete a transaction. 
   2.7.5 Hybrid Messaging 
   Referring to  FIG. 23 , in some scenarios a multi-transaction messaging without user interaction is performed to play an object. Some examples of hybrid messaging are:
         Consider a scenario where a low-end mobile phone player without support for the suitable push-based notification, wishes to play an unbounded object. A hybrid solution can be adopted to push a small notification to the device, notifying the player application (i.e. through SMS) to initiate a stream-based communication to the Netpage Server request (i.e. WSP) for delivery of the object.   Displaying a URL object also uses a multi-transaction hybrid messaging, where the original object (the URI) is pushed to the device using a Notification message. At this point the player (without user interaction) retrieves the URI content by sending a synchronous request/response message through HTTP.
 
2.7.6 Player Session Establishment
       

   When players  520  are instantiated on devices (for instance during user login on a desktop player or on-demand by the mobile user), the player  520  registers the mobile device  100  is available for play requests by initiating a player session  580  with the Netpage Server  529 . 
     FIG. 24  shows the basic lifecycle of a NetpagePlayer session  580 . First, a process, which is typically running on a remote machine/device, calls the startPlayerSession( ) method  581  to commence a NetpagePlayer session  581  with the Netpage Server  529 . A userId  582  is provided which indicates the user  525  to which the supplied player  520  should be associated. Upon reception of a startPlayerSession( ) request  581 , the server  529  creates a PlayerSession object which is returned to the remote process  583 . This object can be used at some later time to terminate the session by calling the terminate( ) method. 
     FIG. 25  shows more details of the handling a player session  580  within the server  529 . As shown previously, a player session is created  589  by calling the startPlayerSession( ) method on the Netpage Server&#39;s CommandProcessor. This causes the creation of a PlayerSession which in turn creates a NetpagePlayerProxy which is run within the server and acts as a proxy for the real player by implementing the NetpagePlayer interface and passing all requests on to the real player. NetpagePlayerManager::addSession( ) is called to register the session with the NetpagePlayerManager. The NetpagePlayerManager is a singleton object responsible for managing all NetpagePlayer sessions and also for coordinating all NetpagePlayer traffic within the server. 
   2.8 Player Deployment 
   2.8.1 Player Connectivity 
   Netpage Player  520  can be deployed on various devices with different network connectivity capabilities. Table 3 lists some examples of player network connectivity and transmission mechanisms. Note that a deployment environment may utilize a combination of connectivity types. Each connectivity type explains how one hop communicates to the next hop. For instance a player communicates with a wireless gateway on the path to the Netpage Server. 
                                 TABLE 3                   Netpage Player Connectivity Types            Player               Connectivity   Comments   Example Standards               Local   On a desktop device or a smart mobile, the player communicates   Shared memory,           with the next hop locally through the on-board IPC mechanisms.   TCP/IP on the loop-           The next hop could be the server running on the same desktop, or   back interface, etc.           the micro server running on the smart mobile, or the gateway to           the remote server running locally.       Fixed Network   The connectivity to the next hop is over a fixed (wired) network.   TCP over the Internet           For instance the desktop player communicates to the remote   through a dial-up serial           server through IP-based protocols over Internet.   link, etc.       Short-range   The player connects to the next hop through a Wireless Personal   IrDA, Bluetooth,       wireless   Area network (WPAN). For instance a player running on a PDA   802.15, etc.           uses Bluetooth to communicate to a Relay module running on a           local desktop.       Long-range   The player communicates with the next hop through a long-range   802.11a, b, g, GPRS,       wireless   wireless network with national (WLAN) or global (WWAN and   WCDMA, etc.           Satellite) coverage. For instance the player is a WAP-enabled cell           phone connecting to the remote server over GPRS wireless           network.                    
2.8.2 Player Deployment Configuration
 
   Different combinations of player devices and connectivity types can be configured to provide a suitable Netpage Player and Server integration environment.  FIGS. 26 to 29  demonstrate some of the more widely applicable types of deployment environments. Example pen connectivity is demonstrated for clarity. 
   3. Object Association Design 
   3.1 Object Associations Overview 
   A Netpage object association allows content (objects  601 ) to be associated with locations  513  on Netpage documents  603  and printouts. Arbitrary content types can be supported, but common examples include pictures/photos, audio, and video. 
   An object  601  can either be associated  616  with a document during the authoring of the document (static association) or can be associated with a particular document printout at some arbitrary time after that printout has been created (dynamic association). 
   Additionally, an association  616  may either be an impression association or a field association. An impression association is a dynamic association that is associated with a particular {x,y} location  613  on an impression. A field association is associated with a particular field of a form (static association) or form instance (dynamic association). 
   3.2 Communicating Status to the User 
   At times the mechanisms described require communication of status information (often errors) to the user. The simplest way to achieve this is to make use of the Netpage Player infrastructure. Special operations (e.g. show-status-ok-message and show-status-error-message) can be designated for transmitting status information to the user. The player architecture would determine, for each message, the most appropriate device (or devices) on which to display the message and the way in which to display it. For example, it may be that in certain situations the pointer is the only available player, in which case an error status might be “played” by illuminating a red LED on the pointer or playing a short sound. 
   3.3 Impression Associations 
   An object  601  can be associated dynamically with a specific {x,y} location  613  on an impression. The associations  616  are stored inside the Netpage Server  529  and can then be viewed in a number of ways:
         1. By interacting with the physical impression using a device that communicates with the Netpage Server  529  to retrieve the associated objects  601 .   2. By interacting with a virtual view of the impression from within a graphical software application  602 .
 
3.4 Interacting with Dynamic Associations
       

   Referring to  FIG. 30 , an associated object  601  can be viewed by interacting with the physical impression using a Netpage Tag aware device. This shows an example where a tag reading device with built in screen is passed over a physical impression. The device communicates impression locations to the Netpage server  529  which responds with information regarding any associated object  601  that is currently sensed by the device. Depending on configuration, the device might begin immediately playing each associated object or present the user  525  with the option of playing the object  601 . If multiple objects  601  are within the device&#39;s field of view, then the device could present the user with a list of the objects  601  for selection. 
   Associated objects  601  can also be viewed by interacting with a virtual view of the impression from within a graphical software application  602 . There are a number of possible mechanisms for displaying associated objects  601  in such an application  602 . Each mechanism is responsible for:
         Indicating the presence of an associated object (or objects  601 ), and   Displaying the actual content of an associated object  601 .       

   An example mechanism is shown in  FIG. 31  where a graphical “Netpage Explorer” application  602  is being used to view an impression which contains associated objects  601 . The example shows an approach in which some visible token  603  (in this case a black star) is displayed that indicates the locations that contain object associations  616 . The display of the tokens  603  can be toggled by clicking on a toolbar button  609 . To view an associated object  601  the user clicks (or alternatively double-clicks) on the relevant token  603  which causes the Netpage Explorer application  602  to retrieve the associated object  601  from the Netpage Server  529  and to then play the object  601 . Depending on the capabilities of the Netpage Explorer application  602 , the object  601  can either be played within the Netpage Explorer application  602  itself, or by an external application. 
   3.5 Methods for Creating Impression Associations 
   This section describes various alternative techniques that may be provided to allow users to dynamically associate content with a location on an impression. They include:
         Modal association mechanisms   Sticker based mechanisms   Swipe Based mechanisms   Swipe Based Stickers
 
3.5.1 Modal Association
       

   A Modal Association involves first placing the user/pen session in a mode in which the next pointer click is interpreted as the specification of an impression location to which a current clipboard object  601  should be associated. 
     FIG. 32  shows an example of how an impression object association  617  might be created modally. In this case, the user attaches a photo to an impression. The steps are as follows:
         1. The user takes a photograph using their digital camera  610 .   2. The user pushes the photograph to the Netpage clipboard on the Netpage Server  529  (possibly implicitly).   3. The user clicks with their Netpage pointer  533  on a printed toolbar  611 . In this case, the user clicks on the “Attach Object” button  612 . This places the pointer session into a mode in which the next click with the pointer  533  is interpreted as the specification of an impression location to which the current clipboard object  601  should be associated.   4. The user clicks on the desired location  613  on a printed page  614 . This causes the Netpage Server  527  to retrieve the current object  601  from the user&#39;s clipboard  615  and to associate the object with the impression location selected in step 3.       
   An alternative approach requires steps 3 and 4 to be performed in the opposite order. That is, the “Attach Object” command is interpreted to mean associate the object with the impression location most recently touched by the user. 
   Modal association mechanisms can be implemented on top of the Netpage Clipboard  615  mechanism. 
   3.5.2 Tagged Stickers 
   A tagged sticker  620  is a physical adhesive sticker which is Netpage tag encoded  617 . That is, it is a Netpage impression printed onto a physical sticker. Clicking on a tagged sticker causes an object to be associated with that sticker (impression). Tagged stickers  620  can be physically attached to any surface whether it be tagged or otherwise (eg. books, desks, walls, etc) and thus provide a very flexible mechanism for dynamically associating objects with locations. 
     FIG. 33  shows an example of a simple tagged sticker  620 . In order to associate an object  601  with the sticker  620 , the user would perform the following steps.
         1.Push object  601  into Netpage Clipboard  615     2.Physically paste sticker  620  onto any surface   3.Use Netpage pointer  533  to click on the sticker  620  to associate the object  620 .       
   Once an object  601  has been associated with a sticker  620 , there are various ways in which the user can retrieve/play the object  601 . Firstly, the object  601  can be interacted with using a physical Netpage Player device  520 . Secondly, simply clicking on the sticker  620  with a Netpage pointer  533  would cause the object  601  to be played. This latter behaviour suggests that sticker associations would actually be implemented as field associations  618 . 
   3.5.3 Reusable Stickers 
   As so far described, once an object  601  is associated with a sticker  620 , that association  616  cannot be altered. A reusable sticker  621  allows for the object associated with a sticker to be changed, or erased. Such a sticker  621  is shown in  FIG. 34 . The “Attach” button  622  is used to associate an object  601  with the sticker  621  and allows for a new object  601  to be associated with the sticker  621 , overwriting any previous association  616 . The “Clear” button  623  allows for any association  616  to be removed. 
   Both “Attach”  622  and “Clear”  623  are destructive operations in that they remove any association  616  that may have been in place before the operation took place. As such, it may be desirable to be able to protect against accidental invocation of such operations, especially in the sticker scenario in which the entire sticker is a clickable area. 
   One mechanism for doing that is shown in  FIG. 35  in which a sticker  621  has a “Confirm Action” button  624 . In order for a destructive operation to be confirmed, the user must first select the operation and subsequently select the “Confirm Action” button  624 . A suitable timeout (say 10 seconds) can be used such that confirmations must take place within the timeout period in order to be valid. 
   An alternative for preventing accidental invocation of destructive operations is to limit the interactivity of the sticker to small areas within the sticker as shown in  FIG. 36 . The associated object  601  is only played when the user selects the “Play” operation  625 . The overall sticker  621  is not interactive. As such, accidental invocation of destructive operations should be much less likely. 
   3.5.4 Category Specific Stickers 
   So far we have described stickers which retrieve the object  601  most recently assigned to the Netpage Clipboard  615 . The Netpage Clipboard  615  can store multiple objects  601  per user  625  with each object  601  falling into an object category or set of categories. As such, it is possible to have Category Specific Stickers  627  that retrieve current objects from the Netpage Clipboard  615  by category. 
     FIG. 37  provides examples. Clicking “Attach” on the left sticker causes the current clipboard object  601  with a category of “video” to be associated with the sticker  620 . The sticker on the right achieves a similar effect for objects in the “photo” category. 
   3.5.5 Swipe Based mechanisms 
   The printed toolbar in  FIG. 38  allows an impression association  617  to be created by swiping a command from a printed toolbar  626  to the location on an impression to which the object  601  is to be associated. The user temporarily places the toolbar  626  on top of the destination impression and swipes from the toolbar  626  to the impression. The swiping action provides the system with digital ink samples from both the toolbar and the destination impression. These samples enable the determination of both which object  601  is to be associated (for the card shown the possibilities being the current video clip, current photo, current audio clip, or in the case of the “Any” icon, the current object regardless of type) and to which impression and location on that impression the object  601  is to be associated. 
   3.5.6 Swipe Based Stickers 
   A limitation of the stickers described earlier is that they do not actually create an association  616  between the object  601  and the underlying impression on which the sticker is applied. For example, consider the situation where a sticker has been applied to a tagged impression, and subsequently an object  601  is associated with the sticker. If the underlying impression is viewed within the Netpage Explorer application, then the sticker and associated object  601  is not be displayed since the Netpage Server  529  is not aware that the sticker has been applied to that impression. 
   The above problem can be solved by applying the swipe based approach to stickers. The user steps involved are:
         1. Push object  601  into Netpage Clipboard  615     2. Physically paste sticker  620  onto a tagged impression  600     3. Use Netpage pointer  533  to swipe from sticker  620  to impression  600 .       

   The action of swiping across both the sticker  620  and the impression  600  creates a triple association between the impression  600 , the sticker  620 , and the object  601 . Specifically, the Netpage server  529  is now aware of:
         The sticker  620  to which the object  601  has been associated, and   The impression  600  on which the sticker  620  has been placed, and the location  613  on the impression  600  at which the sticker  620  has been placed, and thereby the location  613  on the impression  600  to which the object  601  is associated.       

   The above associations  616  allow the object  601  and sticker  620  to be displayed inside tools such as Netpage Explorer  602 . 
   A variant of the swipe based sticker is shown in  FIG. 39 . It includes a transparent region  628  hich allows the tags of the underlying impression  600  to be seen through the sticker  620 . This makes it possible to create a triple association  616  with a swipe that remains within the confines of the sticker  620 . 
   In addition, the transparent region  628  may be transparent in the infrared spectrum in order for the Netpage pointer  533  to be able to see the Netpage tags on the underlying impression  600 . This allows for the transparent region  628  to be non-transparent in the visible spectrum. As such, graphics can be printed over the transparent region  628 . For example, a swipe based category specific sticker can be constructed which includes indicative graphics printed over the transparent region  628  as shown in  FIG. 40 . It is also possible that the instead of using a transparent region  628 , the sticker  620  may alternatively include a hole. 
   3.5.7 Impression Associations Object Model 
     FIG. 41  shows the basic object model representation of impression associations  617 . An ImpressionAssociation  617  includes a location and the object&#39;s content. An ImpressionLocation includes an {impression,x,y} tuple  629 . The content of an associated object is represented as a PlayRequest  521 . In the common case, the PlayRequest  521  includes a single value, but it also possible to associate targets and operations. For example, any PlayRequest  521  can be associated with an impression 
   A swipe based sticker is associated with an ImpressionAssociation on the underlying impression. 
   3.6 Field Associations 
   An object  601  can be dynamically associated with a particular field of a form instance  630 . Such an associated object  601  is then delivered to the relevant application as part of a submission of the form instance  630 . This can be used, for example, to dynamically attach images (e.g. photos) to a Netpage form  632  and to then have those images sent to the application when the user clicks on the “submit” form command. 
   The relationship between field associations  618  and impression associations  617  is shown in  FIG. 42 . A FieldAssociation  618  consists of a specification of the field with which the object  601  is associated and a reference to the underlying impression association  617  which provides details of the actual object  601 . The ImpressionAssociation  617  structure has been described. The field is specified by a FieldlnstanceAddress  631  which specifies a form  632  instance  630  and a field number  633  within that form instance  630 . A Formlnstance  630  is a specific instance of a Form  632  which is printed on to a Printout  633 . 
   3.6.1 A Sample Application 
     FIG. 43  shows a simple application that demonstrates the use of field associations  618 . Use of the application proceeds as follows:
         1. The user clicks on the “Click here to attach photo” button  640  with a Netpage pen  533  or pointing device. This causes the application to request the current photo from the Netpage clipboard  615  associated with the user  525 . That photo is then associated with the large rectangular field  641 .   2. The user can click on the large field  641  in order to retrieve the associated photo and display it on a suitable Netpage Player device associated with that user  525 .   3. The overall form can be submitted by clicking on the “Submit” button  642 . This causes a form submission to be sent to the relevant application. The form submission includes the photo currently associated with the large field  641 .       
   The following sections use the sample application to describe the remaining details of the field association mechanism. 
   3.6.2 Form Design for the Sample Application 
   In order to design a form  632  that supports a simple application, two forms are specified. The first form  643  is a standard application form. The second form  644  is a special form that include fields that share the same impression coordinates as elements from the first form, but are overlayed on top of the first form&#39;s fields. 
   The underlying (first) form  643  is shown in  FIG. 44 . This includes a submit button  642  for the application and also a field of type ObjectReceiver  644 . It is to this second field  644  that an object is to be assigned. The actual assignment occurs as a result of user interaction with the overlayed form as described below. 
   The overlayed form  644  is shown in  FIG. 45 . The application name for the overlayed form  644  is the system supplied “sys:object-associator” application. This is a standard internal application that expects to receive a form submission with a “submit” button having one of the names as shown in Table 4. The table describes the meanings of each of the possible submit buttons. Note that an object-associator form does not need to provide all four submit buttons, although it must minimally provide both a “set” and a “target” button. 
   
     
       
             
           
             
             
           
         
             
               TABLE 4 
             
           
           
             
                 
             
             
               Submit buttons supported by the sys: object-associator application 
             
           
        
         
             
               Name 
               Description 
             
             
                 
             
             
               set 
               The set command indicates that an object of the specified type is to be fetched 
             
             
                 
               from the Netpage clipboard and associated with an ObjectReceiver field on the 
             
             
                 
               underlying form. The location of the relevant ObjectReceiver field is indicated by 
             
             
                 
               the “target” field that must also be part of this form. 
             
             
                 
               The type of object to be associated is indicated by the field&#39;s value. If it is left 
             
             
                 
               blank, then the current clipboard object (regardless of type) is retrieved and 
             
             
                 
               associated. 
             
             
               clear 
               The clear command indicates that the object association currently assigned to the 
             
             
                 
               “target” field should be removed. 
             
             
               show 
               The show command causes the object associated with the target field (if any) to 
             
             
                 
               be displayed on a suitable Netpage Player. 
             
             
               target 
               The target field has two roles. Firstly it indicates the location/field on which the 
             
             
                 
               set, clear and show commands should act. Secondly, if the target field is clicked 
             
             
                 
               then it behaves as if it is a show command. 
             
             
                 
             
           
        
       
     
   
   The below pseudo code outlines the handling of the set command. The main principle to note is that the center of the target field provides the {x,y} location to which the retrieved object should be associated. This {x,y} location is also used to locate a form field with which the object is to be associated. This is achieved by determining the uppermost field on the page that intersects with {x,y} and that is also receptive to object associations. In the case of the example, the uppermost field on the page that intersects {x,y} is the target field itself, but it being a submit field, is not receptive to object associations. The next uppermost field that intersects {x,y} is the ObjectReceiver field on the underlying form. The end result is that the object is associated with a field on the underlying application form rather than the overlayed sys:object-associator form. 
                               ObjectAssociatorApp::handleSetCommand(a_submission,       a_formDescription)       {        let l_setField = a_submission.getSubmitButton( )         // fetch the target field for the current form        let l_targetField = a_formDescription.fetchField(“target”)         // Calculate the impression location to which the object is to be         // associated. The center of the “target” field is used as the         // location to place the object.        let l_targetCenter = l_targetField.center( )        let l_location =           ImpressionLocation(a_submission.getImpressionId( ),           targetCenter);         // Look for a receptive field to which we can associate the object.         // A receptive field is a field with a type that indicates it is         // receptive to object associations. “submit” fields are not         // receptive, but most other field types are. N.B. The receptive         // field is typically on another form.        let l_targetField =            (the uppermost receptive field on the page that includes       l_location)         // Retrieve an object of the appropriate type from the       NetpageClipboard.         // The type to retrieve is indicated by the “value” element of the         // “set” field        let l_objectRequestType = l_setField.value( )        let l_clipboard = getClipboard(l_submission.userId( ))        let l_object = l_clipboard.fetchObject(l_objectRequestType)         // create the associations        let l_impressionAssoc = createImpressionAssociation(l_location,        l_object)        createFieldAssociation(l_targetField, l_impressionAssoc)       }                    
3.6.3 Field Associations and Form Submissions
 
   Netpage forms  632  generally have one or more form submission buttons  642 . Clicking on such a button  642  with a pointer  533  causes the Netpage server  529  to perform handwriting recognition of the digital ink (if any) assigned to the form  632 , and to bundle the result into a form submission which is then posted to the application associated with the form  632 . The handwriting recognition largely involves converting handwriting fields (such as textual combs, and check boxes) into their digital equivalents (for example digital ink in textual combs is converted to text). 
   Associated objects  601  can optionally be submitted as part of such form submissions. The requirement to transfer an associated object  601  (or otherwise) as part of the form submission is specified in the form definition for that form. 
   3.7 Static Associations (Embedded Objects) 
   Objects  601  can be associated with a document at document creation time. As with dynamic associations, such associations can either be impression associations  617  or field associations  618 . Static associations are specified in the Interface Description for the document. Static associations are represented as PlayRequests  521 . 
   4. Netpage Clipboard 
   The Netpage Clipboard  615  is a system supplied, per user object repository to which the user can push an object  601 . The object  601  thus pushed is considered to be the user&#39;s “current object” which may then be accessed by applications, in particular by the UserRequestRouter, but in general by any application that is acting on behalf of the user. 
   4.1 Representation of Clipboard Objects 
   Clipboard objects are stored as Netpage Player PlayRequest objects  521 . A PlayRequest  521  corresponds to a request to perform an action. It consists of three parts:
         1. A target, which specifies on which player (device) the request should be executed.   2. The operation, which specifies the action to be taken.   3. A set of values, which are supplied as parameters to the operation.       

   A Value represents an instance of some physical type and consists of a type specification and data. The type specification has a physical type and zero or more associated type categories. The physical type identifies the structure of the data element of the Value. This document does not specify a particular representation for physical types. A possible mechanism would be to use MIME types. For example, if the physical type is image/jpeg then the data element would contain the binary data of an image in jpeg format. 
   A shorthand form of specifying PlayRequests will now be used in this section. As an example, instead of using the tabular form this section will use the following syntax for PlayRequests that only have a single item:
         value {phone-number, “555 3473”}       

                                                   target                   operation           values   phone-number   “555 3473”                        
4.2 Mechanisms for Pushing Values to the Clipboard
 
   In general, a user performs an explicit user action in order to push a value to the clipboard. Such actions may take various forms as described in the following sections. Once a value is in the clipboard any application can access the value. For example the value can be dynamically associated with a form field on a printed impression. 
   4.2.1 Push Via Printed Netpage Form 
   Values can be pushed to the clipboard by interacting with a printed Netpage form such as that shown in  FIG. 46 . The form has been authored such that clicking on any of the phone numbers causes that phone number to be sent to the Netpage clipboard  615  for that user  525 . For example, clicking on the phone number for “Susan Wilson ”  615  causes the following value to be pushed to the clipboard  615 :
         value {phone-number, “151 425 0617”}
 
4.2.2 Push Via Physical Device
       

   Values  524  can be pushed to the clipboard  615  by Netpage aware devices that are capable of capturing and/or storing typed objects. Table  5  provides some example devices and scenarios in which they might push values to the Netpage clipboard  615 . 
                             TABLE 5                   Examples of Netpage aware devices capable of pushing objects to the clipboard            Device   Example scenario               Digital Camera   User takes a photo with the digital camera and then selects “Send to Netpage”           from a menu. This results in the photo being added to the Netpage clipboard (say           with type: image/jpeg).       mp3 audio players   User chooses a favourite song (or song collection) on the audio player and           selects “Send to Netpage” from a menu.       Video camera   Similar to the digital camera scenario, but for video instead of still photo.       Dictation device   User records a message and then pushes the audio file to the Netpage clipboard.                    
4.2.3 Implicit Push
 
   To improve usability, it may be possible for certain devices to support implicit (or auto) push which is where certain user interactions with a device cause a value to be automatically pushed to the Netpage clipboard  615 . As an example, the user may configure their digital camera so that taking a photo causes the photo to be pushed to the Netpage clipboard  615 . 
   4.3 Netpage Clipboard Interface 
   In order for a device or application to push a value to the Netpage clipboard  615  or retrieve the current object  601 , the device or application first retrieves a reference to a NetpageClipboard object for that user from the Netpage server  629 . The following listing shows the NetpageClipboard interface in its most basic form. The interface allows the current clipboard value to be set, fetched and cleared. 
   
     
       
             
             
           
         
             
                 
                 
             
           
           
             
                 
               interface NetpageClipboard 
             
             
                 
                { 
             
             
                 
                 void 
             
             
                 
                 setObject(in PlayRequest a_object); 
             
             
                 
                 PlayRequest 
             
             
                 
                 fetchObject( ); 
             
             
                 
                 void 
             
             
                 
                 clear( ); 
             
             
                 
                }; 
             
             
                 
                 
             
           
        
       
     
   
   The sections that follow discuss alternatives for various aspects of the Netpage clipboard interface. 
   4.3.1 Multiple Values Per User 
   The Netpage clipboard  615  is able to support multiple current values each of which belong to a different category. For example, the clipboard  615  can hold a current audio and current video at the same time. PlayRequest values can specify one or more categories to which that value belongs. Note that an object category is generally independent of the specific physical type of the value being added to the clipboard. For example, setObject( ) might be called with a value that has a category of “photo”, and a physical type of image/jpeg. 
   This listing shows a NetpageClipboard interface that supports multiple current values. 
   
     
       
             
             
           
         
             
                 
                 
             
           
           
             
                 
               interface NetpageClipboard 
             
             
                 
                { 
             
             
                 
                 void 
             
             
                 
                 setObject(in PlayRequest); 
             
             
                 
                 PlayRequest 
             
             
                 
                 fetchObject( ); 
             
             
                 
                 PlayRequest 
             
             
                 
                 fetchObject(in ObjectCategory); 
             
             
                 
                 void 
             
             
                 
                 clear(in ObjectCategory); 
             
             
                 
                 void 
             
             
                 
                 clearAll( ); 
             
             
                 
                }; 
             
             
                 
                 
             
           
        
       
     
   
   Such a clipboard would still support the current object concept which would return the most recently added object. To that end, the clipboard interface in the listing has two fetchObject( ) methods. The first takes no parameters and returns the most recently added object. The second takes an ObjectCategory as a parameter and returns the most recently added object which belongs to the specified object category. 
   More generally the clipboard could reuse the general capability matching mechanism required by RequestRouters in the Netpage Player architecture. This would provide the clipboard with a very powerful interface for retrieving PlayRequests. 
   4.3.2 Multiple Representations of Values 
   As with clipboards in standard desktop environments, it may be desirable to allow the Netpage clipboard to support multiple representations of values, each of which would have a different MIME type. For example, a text object could be stored as both a text/plain and a text/rtf document. 
   4.3.3 Using Values from the Netpage Clipboard 
   Once a user places a value in the clipboard, the value can be accessed by applications in response to actions by the user. The basic clipboard interaction model is shown in  FIG. 47 . Referring to  FIGS. 47 and 48 , the clipboard starts empty  652 . A value can then be pushed  653  into the clipboard  615 . At that point an operation can be selected  654  by the user at which point the selected operation is executed against the current value in the clipboard. If an operation is selected while the clipboard is empty, then an error  655  is returned to the user. 
   The model presented in  FIG. 47  is called the value first model as it requires the user to first select the parameter to an operation, and to then select the operation itself. 
   One way in which an operation can be invoked by a user is for the user to interact with a printed Netpage form  660  which contains a set of PlayRequests which specify operations.  FIG. 48  shows such a printed command sheet and Table 6 describes the meaning of each operation. When a field is selected by the user (by clicking on it with a Netpage pointer), the corresponding operation is performed on the value currently stored in the clipboard 
                             TABLE 6                   Description of commands            Command   Descriptions               Play   Executes the default action for the current clipboard value. For example, for a           phone number object, the default action might be to dial the number, while for           an image it might be to display the image on a device capable of image display.       Display   Display the current clipboard value. This is different to play, since for a phone           number, for example, the phone number is displayed rather than dialled.       Attach to Page   Associate the current clipboard value with a location on a printed page.       Print   Print the current value.                    
4.4 Placing Operations and Targets in the Clipboard
 
   As clipboard entries are actually stored as PlayRequests  521  it is also possible to push operations and targets to the clipboard  615 . 
   4.4.1 Adding Operations to the Clipboard 
     FIG. 49  shows a clipboard model which allows operations  523  to be stored in the clipboard  615  rather than values. In this model, the user pushes an operation  523  to the clipboard  615  at step  661 , and then selects the value  524  to which the command  523  should be applied at step  662 . So, for example, a “play” operation could be pushed to the clipboard  615 , and then a phone number could be subsequently selected from a contacts list as already shown in  FIG. 46 . This model is called the operation first model as it requires the user to first select an operation  523 , and to then select the parameter  524  for the operation  523 . 
   4.4.2 Allowing both Value First and Operation First Models 
   It is possible to simultaneously support both the value first and operation first models as shown in  FIG. 50 . In this model an empty clipboard  615  allows an operation  523  or a value  524  to be pushed at steps  663  or  664 . This gives the user the freedom to perform operations  523  in whichever order seems natural. Also, if a user is using operation first, then once the user has placed an operation  523  in the clipboard  615 , they can perform that operation  523  on as many values  623  as required simply by pushing values to the clipboard  615  at step  665 (and vice-versa for value first at step  666 ). In order for a user to switch between models, however, the clipboard  615  must be explicitly cleared at steps  667  and  668 . 
   The following examples show the two models in action. In each case, the user&#39;s steps are shown numbered and the contents of the clipboard  615  are shown after each step. In the first case, the user uses the value first model by first pushing a phone number to the clipboard  615 , and then selecting the operation  523  to be applied to that object: 
   
     
       
             
             
           
         
             
                 
                 
             
           
           
             
                 
               Push value 
             
             
                 
               value { phone-number, “555 1287” } 
             
             
                 
               Push operation 
             
             
                 
               value { phone-number, “555 1287” } 
             
             
                 
               operation { play } 
             
             
                 
                 
             
           
        
       
     
   
   At this point, an observer of the clipboard  615  (likely the UserRequestHandler) determines that the PlayRequest  521  as shown below can be produced by combining the operation  523  and value  524  PlayRequests  521 . The resultant PlayRequest  521  can then be routed by the UserRequestHandler. Typically the UserRequestHandler “plays” a phone-number by sending the request to a device capable of dialling the phone number.
         PlayRequest created by merging contents of clipboard:       

   
     
       
             
             
             
             
           
         
             
                 
                 
             
           
           
             
                 
               target 
                 
                 
             
             
                 
               operation 
               play 
             
             
                 
               values 
               phone-number 
               “555 1287” 
             
             
                 
                 
             
           
        
       
     
   
   The second case uses the operation first model: 
   
     
       
             
             
           
         
             
                 
                 
             
           
           
             
                 
               Push operation 
             
             
                 
               operation { play } 
             
             
                 
               Push value 
             
             
                 
               operation { play } 
             
             
                 
               value { phone-number, “555 1287” } 
             
             
                 
                 
             
           
        
       
     
   
   At this point, the clipboard  615  determines that the PlayRequest  521  can be produced by combining the operation  523  and value  524  PlayRequests  521 . 
   4.4.3 Ambiguous Usage 
   One problem associated with this mechanism of pushing values  524  or operations  523  to the clipboard  615  is a value  529  or operation  523  can remain in the clipboard  615  indefinitely. As such, it is easy for a user  525  to forget that an object  601  is in the clipboard  615  and for unexpected results to emerge. This is particularly the case if we simultaneously allow both the value first and operation first models. As an example, suppose the user performs the following actions:
         1. Push “play” operation to the clipboard   2. Push a phone number (the number is dialled)   3. An hour later, click on another phone number.       

   Using the state machine indicated by  FIG. 50 , step (3) would cause the number to be dialled. This may not be what the user expected as they have likely forgotten the fact that the “play” operation is currently residing in the clipboard. 
   There are a number of approaches to addressing these useability concerns:
         Single Use Clipboard Entries   Clipboard Timeouts
 
4.4.4. Single Use Clipboard Entries
       

     FIG. 51  provides an alternate model to that previously described. In this model, using an item in the clipboard  615  at either of steps  525  or  626  results in that item being removed from the clipboard  615  at state  670 . That is, op  523  and values  524  only remain in the clipboard  615  for a single use after which the clipboard  615  is returned to the Clipboard Empty state  627 . This model largely avoids the useability concerns described above, although not completely, as will be described in further detail. 
   4.4.5 Clipboard Timeouts 
   While a single-use clipboard model improves the useability of the Netpage clipboard  615 , there are still problematic scenarios which result from allowing both value first and operation first models to coexist. Consider the following steps:
         Push “play” operation to the clipboard  615     An hour later, push a phone number       

   In the above, it is not clear whether the user  525  has indicated that they would like to apply the “play” command to the phone number, or whether they had forgotten that they had pushed the “play” operation an hour ago and were actually attempting to simply push a phone number to the clipboard  615 . 
   In order to address the ambiguity, the concept of clipboard timeouts can be introduced, as shown in  FIG. 52 . In this model, objects only remain in the clipboard for a limited duration, 60 seconds in the example for steps  675  and  676 , but the exact value could be user configurable. 
     FIG. 52  shows clipboard timeouts in the context of a single-use clipboard. It is also possible to introduce clipboard timeouts within a multi-use clipboard, as shown in  FIG. 53 . Each application of an operation to a value at steps  680  and  681  resets the timeout period which allows for multiple values to be applied to an operation without having to push the operation each time. Similarly, it allows multiple operations to be applied to a value without having to push the value each time. 
   4.4.6 Multi Value Operations 
   The clipboard  615  concept can be extended to support operations that require more than one parameter  524 . The basic approach is to allow multiple values  524  to be pushed to the clipboard  615 . The clipboard  615  can then combine the values  524  with a pushed operation  523  to create a PlayRequest  521  with multiple parameters. 
   4.4.7 Adding Targets to the Clipboard 
   Consider the command sheet already shown in  FIG. 48 . Clicking on each operation with a Netpage pointer  533  causes the corresponding operation  523  to be pushed to the clipboard  615 . The operation  523  does not necessarily take effect immediately. The operation takes effect when there is sufficient information available in order to determine the full details of the PlayRequest  621  being requested by the user  525 . There are cases in which it proves valuable to allow the user  525  to be able to specify the target  522  of an operation  623 . For example, suppose a user wishes to print a photo from their digital camera, but does not wish to print it to their default printer. 
   Selection of the printer can be achieved by selecting the printer from a list of printers printed on a Netpage card  700  as shown in  FIG. 54 . Clicking on a printer  707  on the card simply causes the details of that printer to be pushed to the Netpage clipboard  615 . 
     FIG. 55  shows the details of each of the fields on the card. Each field corresponds to a PlayRequest ( 521   a ,  521   b ,  521   c ,  521   d ,  521   e ,  521   f ,  521   g ) that specifies a target  522  and nothing else. 
   The following steps provide an example in which the user pushes a target to the clipboard. 
   
     
       
             
           
         
             
                 
             
           
           
             
                1. Push photo of family dog to clipboard 
             
             
               value { image/png category =”photo”, &lt;contents of photo of dog&gt; } 
             
             
                2. Select printer by clicking on card 
             
             
               value { image/png category =”photo”, &lt;contents of photo of dog&gt; } 
             
             
               target { home-color-printer } 
             
             
                3. Push “print” command to clipboard (e.g. using printed 
             
             
                command sheet shown in FIG. 3 
             
             
               value { image/png category =”photo”, &lt;contents of photo of dog&gt; } 
             
             
               target { home-color-printer } 
             
             
               operation { print } 
             
             
                 
             
           
        
       
     
   
   At this point, a PlayRequest  521  can be constructed that combines all the elements from the clipboard  515  as shown in  FIG. 52 . 
   
     
       
             
           
             
             
             
           
         
             
                 
             
             
               PlayRequest created by merging contents of clipboard 
             
             
                 
             
           
           
             
                 
             
           
        
         
             
               target 
               home-color-printer 
                 
             
             
               operation 
               print 
             
             
               values 
               image/png category =”photo” 
               &lt;contents of photo of dog&gt; 
             
             
                 
             
           
        
       
     
   
   Once the full PlayRequest  521  is determined, it is performed and, depending on the clipboard model being used, the clipboard  615  would either be cleared of all contents (the single-use model), or left as is in readiness for future related requests  521  (the multi-use model). In the latter case, the subsequent act of pushing another photo (say of the family cat) to the clipboard  615  would leave the clipboard  615  in the following state: 
   
     
       
             
             
           
         
             
                 
                 
             
           
           
             
                 
               target { home-color-printer } 
             
             
                 
               operation { print } 
             
             
                 
               value { image/png category =”photo”, &lt;contents of photo of cat&gt; } 
             
             
                 
                 
             
           
        
       
     
   
   At this point, the clipboard contents indicate that the user wishes to print the newly selected photo on the color inkjet printer at home. This approach allows the user to request the printout of a number of photos on a particular printer, without having to specify the target  522  or the operation  523  each time, by simply clicking on each required photo. 
   Even in the multi-use case, if the user is inactive for some configurable period of time, then a clipboard timeout causes the clipboard  615  to be cleared. 
   4.4.8 Pushing More fully specified PlayRequests 
   As the clipboard  615  supports the pushing of PlayRequests  521 , the application author is not limited to pushing values  524 , operations  523 , and targets  522 . It is also possible to push PlayRequests  521  that are more fully specified. For example, consider the printed command sheet  710  shown in  FIG. 56 . It contains various commands  711  that can be invoked by clicking on the sheet with a Netpage pointer  533 . 
     FIG. 57  shows the configuration of one of the commands. Namely, the “print using . . . office printer” command  712 . As can be seen, it corresponds to a PlayRequest  521  that specifies both a target  522  and a command  712 . 
   
     
       
             
           
         
             
                 
             
           
           
             
                1. Push photo of family dog to clipboard 
             
             
               value { image/png category =”photo”, &lt;contents of photo of dog&gt; } 
             
             
                2. Click on “print using ... office printer” field 
             
             
               value { image/png category =”photo”, &lt;contents of photo of dog&gt; } 
             
             
               target { office-personal-printer } 
             
             
               operation { print } 
             
             
                 
             
           
        
       
     
   
   At this point, a PlayRequest  521  can be constructed that combines all the elements from the clipboard  615  as shown in  FIG. 52 . As such, the “print using . . . office printer” command  711  has reduced the number of clicks required by the user to perform the action from three clicks to two. 
                                         PlayRequest created by merging contents of clipboard                                target   office-personal-printer           operation   print       values   image/png category =”photo”   &lt;contents of photo of dog&gt;                    
4.4.9 Communicating Status to the User
 
   At times the mechanisms described may require communication of status information (often errors) to the user. One method is to make use of the Netpage Player infrastructure. Special operations (eg. show-status-ok-message and show-status-error-message) can be designated for transmitting status information to the user. The player architecture would determine, for each message, the appropriate device (or devices) on which to display the message and the way in which to display it. For example, it may be that in certain situations the pointer  533  is the only available player in which case an error status might be “played” by illuminating a red LED on the pointer  533  or playing a short sound. 
   5. Downloadable Content Billing 
   5.1 Overview 
   There is already an existing market place for purchasing and downloading products to mobile devices. Products such as: ringtones (monophone, polyphonic and real tone); wallpapers;. games and other applications; music; music videos; films and TV. The printing capabilities of M-Print can add further to this list of products. 
   The traditional methods for purchasing and downloading such products are based around web browsing and SMS to initiate the download and EMS or MMS to deliver the product to the phone  100 , see  FIG. 58 . The user enters and sends a product code via SMS at steps  720  and  721  to a vendor  723  who then delivers the product to the originating handset  100 , or to the mobile number supplied with the product code at step  724 . 
   Netpage and M-Print technologies have the ability to simplify the user experience in accessing and purchasing these products, while also being able to utilise the existing infrastructure for the billing and delivery of the products. 
     FIG. 59  shows the typical sequence of events for a Netpage play sequence, cast in terms of downloading a preview of a ringtone. In the general Netpage play sequence a Netpage click at step  730  triggers a form submission which in turn results in a general “play” event being routed at steps  732  and  734  to a Netpage player via the Netpage Player Architecture. For downloadable content the form submission is shown as a simple hyperlink  731  and the “play” event is shown as a download of content, in this case a ringtone. 
   Using a Netpage pen or pointer  533  the user  525  can click on a printed advertisement  715  in a magazine, newspaper, direct mail, on a product&#39;s packaging or possibly on a product itself. This can automatically deliver some content to the user&#39;s preferred Netpage Player  520  for that content. Most likely the Netpage Player  520  is the user&#39;s mobile phone  100 , as is shown in  FIG. 59 . Alternatively it can commence a dialogue with the user via the device&#39;s UI to determine what the user wants to do with the product they selected via their click. For content like ringtones or phone themes, this provides a more convenient interface than the existing SMS interfaces in use today. 
   M-Print devices can provide a Netpage scan operation, and this can also be used to initiate a product download or purchase as above. The card that is scanned could have been printed on a M-Print printer  4  or it could be provided along with another product, e.g. a card in a breakfast cereal box. 
   Combining the abilities of M-Print and Netpage can lead to a powerful suite of new product promotion and sales tools. For example, a user can use a Netpage pointer  533  in a mobile phone  100  to click on the latest ringtone advertisement in their favourite magazine. This results in purchasing the ringtone, charging it to their mobile phone account, download and install it on their phone  100 . It can also print on their phone a promotional card that allows a one time download of the same ringtone for them to give a friend. When their friend scans the card they receive the same ringtone downloaded and installed on their phone. Depending on the promotion running at the time the friend may receive the ringtone for free or at a discounted rate. 
   5.2 Downloading Content 
     FIG. 59  shows the typical Netpage player sequence of events that are involved in downloading a product, in this case a ringtone, from a Netpage based application. In the diagram the ringtone download event being routed to the phone in steps  732  and  734  consist of a ringtone, with the play operation of preview  716 . It may have the target handset specified or it may rely on the Netpage player request routing mechanisms to determine the appropriate target  522   25  for the play request  521 . 
   It has already been noted that the mobile computing environment already has some well established mechanisms for satisfying on-line product purchases. Below are three possible ways Netpage player requests can be integrated into the existing mechanisms to provide the user with a simpler user experience. In each of the cases the request to purchase or preview the product is instigated via a Netpage stroke, click or scan The differences arise in how the Netpage application  733  procures the product and delivers it to the user. 
   5.3 Netpage as Middle Man 
     FIG. 60  shows a scenario where the Netpage ringtone application is used as an alternative interface and delivery mechanism to an existing ringtone vendor  723 . The Netpage application  733  does not own the rights to the products it is providing. Instead it is acting as a middleman, forwarding the requests at step  736  onto the product vendor  723  on behalf of the Netpage user and routing the requested product at step  739  back to the Netpage user via the Netpage player mechanism. 
   This approach allows the user to benefit from the Netpage Player Architecture, which allows the user to customize the way they want the product to be routed after they have received it from the vendor. It also allows for the Netpage Player to provide extended handling of products on the mobile device. For example, the player may prompt the user if they wish to back up their existing ringtone before installing a new ringtone or it may guide the user through installing the ringtone as a custom ringtone for a particular phone number or set of phone numbers. 
   5.4 Netpage as a Sales Agent 
     FIG. 61  shows the Netpage application  733  acting as a sales agent for the product vendor  723 . The play request  521  contains the user information and the product ID, and is routed to a special player  743  at step  741  that passes the request onto the vendor  725  at step  742 . The vendor  723  then delivers the product in its normal way, in this case via EMS/MMS at step  744 . 
   5.6 Hybrid Approach 
     FIG. 62  shows a hybrid scenario where the both the Netpage Player Architecture and the existing mobile technologies are used to deliver the purchased product. The request  521  to purchase the product may be satisfied by the ringtone application  733  either internally as a pure Netpage application or acting as a middle man. The play request is dispatched containing both the purchased product and a voucher to be printed. 
   The play request  521  is routed as a Netpage player request and when it reaches a player  745  deployed within the mobile network, acting a mobile device proxy, it is split into a product delivery and a print job. The product is sent out via an EMS/MMS message at step  746  and delivered to the mobile device  100  in the same way as a traditionally purchased product at step  747 . The print job in the form of an M-Doc reference  507  is delivered to the phone  100  via one of the mechanisms initiating a print job on the mobile device  100 . 
   5.7 Billing for Downloaded Content 
   The ability to bill or charge for services and products is at the heart of all businesses. To be able to bill you need to be able to:
         1. identify a party to bill;   2. have a mechanism to deliver and ensure payment of a bill; and,   3. be able to justify the bill based on records of services or products provided.       

   When accessing a service or purchasing a product over a mobile network the user is typically charged for both the data or call traffic involved in making the transaction and also for the product or service purchased. For example, if a ringtone was purchased via Netpage, there is a charge for the ringtone and also a charge the data traffic used to download the content to the mobile device. It is possible for a 3rd party vendor to enter into a commercial relationship with the carrier whereby the carrier waives or reduces the data transfer costs, in return for a payment from the vendor. Mobile carriers play a central role in billing. They own the private networks used by mobile devices to connect to both the public telephone and data networks and it is at their discretion that a mobile device has access to any services. They already have a billing relationship with each of their customers and hence are able to identify them and bill them. Over time the billing options offered by carriers have evolved from the simple post-pay phone bill to include pre-paid, post-paid and plan-based billing, where customers are committed to paying a certain amount per period for which they can access a range of services. Carriers also have the ability to adjust or waive billing based on a user&#39;s activity over a billing period, for example, if you send more than certain number of SMSs in a day then all SMSs is to be charged at a different rate. 
   For pre-paid accounts the account balance is checked before the transaction is commenced to ensure it has sufficient credit to pay for the service. Not all services can predict the total cost before they are delivered and in those cases it is up to the individual carriers to decide whether those services are to be made available to pre-paid customers or not. 
   Mobile carriers recognise the value of their ability to identify and bill customers and make it available to third parties on a commercial basis. They do not make it freely available. The ability to integrate into a carrier&#39;s billing system is typically offered in a number of different ways, of which some are:
         1. SMS/MMS-based services   2. Hosting of 3rd party applications and billing the traffic for those applications differently   3. Billing of data traffic to nominated servers at different rates   4. The ability to bill on behalf of a third party, based on billing records provided by the third party.       

   To bill for products or services attained via Netpage interactions it is necessary to identify where in the sequence of events it makes sense to generate billing records and which party in the transaction is responsible for maintaining and acting on those billing records. To make these services available to users with pre-paid mobile accounts it may be necessary to be able to predict ahead of time the total cost of the transaction. If we consider the SMS-based content download scenario,  FIG. 58 , there are three billing opportunities:
         1. The SMS to initiate the transaction may be a billable SMS   2. The purchase of the content from the vendor   3. The delivery of the content via a SMS or MMS.       

   The first SMS is a standard SMS that the user may be billed for, it may be billed differently given that it is destined for a vendor who has a business relationship with the carrier. The second SMS/MMS is not billed to the sender, as would normally happen, but it is billed to the receiver, via an agreement between the vendor and mobile carrier. In both of these cases the mobile carrier generates and manages the billing records. The purchase cost for the content is also billed to the receiver and the vendor is responsible for generating the billing record. In most cases this billing record is forwarded onto the mobile carrier, typically once a day via a batch transfer. The carrier accumulates these records and includes them on the user&#39;s phone bill as a service for the vendor. The carrier then makes a periodic payment of funds collected on the vendor&#39;s behalf to the vendor. This alleviates the need for the vendor to establish a billing relationship with each of its customers and also allows the mobile carrier to derive more revenue from its existing billing relationship with the customer. 
   For the vendor to be able to generate billing records that a mobile carrier can incorporate into a customer&#39;s bill the mobile carrier needs to provide the vendor with a “customer id” or “billing id” per transaction that the carrier can use to link a billing record with a customer. The provision of customer id and the ability to generate billing records needs to be done in a secure way to reduce the possibility of fraud. To ensure the required security is maintained each vendor enters into a contractual relationship with each mobile carrier before the “customer id” data is shared with them. 
   In situations where a vendor cannot or does not want to work with a mobile carrier they need to implement their own means of identifying and billing their customers. Identifying a user of a mobile device without the assistance of the mobile carrier in a uniform way across all mobile devices is non-trivial. 
   Introducing Netpage and M-Print technologies provide a number of new billing opportunities for all parties involved. If we consider the case where Netpage acts a middle man, there are two billing opportunities:
         1. When Netpage application retrieves the content from the content vendor;   2. For the network traffic used to deliver the click and the ringtone.       

   The Netpage application fetching the content from the vendor generates a billing record for the customer. As for the SMS case above, it is possible to arrange with a mobile vendor to accept these billing records and to bill on the application&#39;s behalf. To do this the data traffic associated with the hyperlink activation is to be tagged with a “customer id” to be associated with the billing record. 
   The mobile carrier tracks the data traffic used to send the click event and deliver the play request. By default that traffic would be billed in the same way as all other data traffic to and from the device. In a situation were the Netpage application is billing via the carrier it may be possible to strike a deal with the mobile carrier where by they waive the data traffic costs in return for a payment per transaction. 
   In the case of Netpage acting as a Sales Agent, the Netpage system is not involved in delivering the product but only in making the sale. In this case there are four billing opportunities:
         1. The data traffic for the Netpage click;   2. The forwarding of the purchase request to the vendor;   3. The purchase of the content;   4. The delivery of the content       

   The mobile carrier tracks and generate billing records for the data traffic and the delivery of the content. As in the SMS case the delivery message is charged to the receiver rather than the sender, via an agreement with the carrier. 
   In this case the billing record for the content purchase generated by the ringtone vendor and would be handled in same way as for the SMS case above. It would be possible to have an agreement with the carrier whereby the cost of the data traffic and the delivery message are waived in return for a payment from the vendor. 
   In most cases the Netpage application would be managed by the vendor as an alternative interface to their existing business and as such it does not need to bill for its forwarding services. If it is run by a different business then it generates a billing record for the forwarding service. This may be delivered either to the user or to the vendor who has agreed to pay for forwarded requests. 
   The billing options for the hybrid approach are essentially the same as for when Netpage is a middle man but the number of deliveries, and hence billable events, to the mobile device is increased. In this case the bill for delivering the M-Doc may be changed to the vendor rather than the customer since it is an unsolicited promotion. Each of these billable events could be filtered by the mobile carrier based on later billing records that enter the system. For example, the cost of delivering the M-Doc may be waived or credited back, if the offer on the printout is taken up by another user. 
   5.8 Digital Rights Management 
   Closely related to billing is ensuring that the product or service is only used for the purpose(s) it was purchased for, eg. a ringtone purchased for one phone, can not be installed on more than one phone, or a music file that is downloaded as a sample can only be played X times before being purchased. 
   Digital Rights Management (DRM) schemes are being adopted by mobile device manufactures and mobile carriers. Where content is being delivered via the existing mobile mechanisms DRM is automatically triggered. The Netpage Player on a mobile device is implemented to hook into the DRM mechanisms on the mobile device. It prevents a user by-passing DRM restrictions on downloaded content. 
   5.9 Identifying the User 
   Mobile carriers identify the user of a mobile device when the device negotiates access to the network, either at boot time or when it comes within range of a base station. For GSM and CDMA networks a user&#39;s identity is determined by matching the International Mobile Subscriber Identity (IMSI) with a user&#39;s records held by the carrier. The IMSI is not sent during negotiation but rather an identity derived from it called a Temporary Mobile Subscriber Identifier (TMSI) is sent. Access to the IMSI can be protected by a PIN and most phones can be set up to prompt the user for a PIN when it is turned on. This is used to gain access to protected data, such as the IMSI. During the connection time negotiations the International Mobile Equipment Identity (IMEI) is also transmitted. This is not used to determine who the user is, but it is used to filter out mobile devices that are blocked from the network, e.g. stolen mobiles can be blocked based on their IMEI. 
   When a mobile network allows a user on a GSM network, they assign the user a SIM card and then activate the SIM card. For a non-pre-paid SIM card the user needs to present sufficient identification information that the carrier is satisfied they know who the person is, that they are able to pay their bill, and where to send the bill. For a pre-paid account the carrier does not need such information, but some countries do require carriers to collect user identity information even for pre-paid accounts. Once the user has an activated SIM card it can be used from any handset and the correct account is billed for usage. Users are encouraged to protect their SIM cards with a PIN, so that it cannot be used until a PIN is supplied. However this is not enforced by the carriers, as it is a user choice. 
   The Netpage system, includes the concept of a Netpage user, each of whom has a Netpage account. Some Netpage applications require knowledge of the user. To be able to access those applications via a Netpage pointer or scanner built into a mobile device, a link between the mobile device and a Netpage user is established. To do this there is a configuration and activation step, similar to a SIM card activation where the Netpage sub-systems on the mobile device are configured and a mapping is setup between the user identity for the mobile device and a Netpage user. If the Netpage account is being established for the first time then, as with a mobile carrier, the user identifies themselves so that the Netpage network operator is able to bill the user for any Netpage related costs incurred. 
   There are times where a mobile user&#39;s identity cannot be determined via a mobile carrier: possibly a company does not want to or cannot get the information from a carrier; the mobile device may be connecting to the network without a carrier being involved; or the carrier may not have the information required, eg. anonymous pre-paid accounts. In these situations the functionality available to the user can be reduced to functionality that does not require knowledge of the user&#39;s identity or additional Netpage specific information can be used to establish the user&#39;s identity to the satisfaction of the Netpage system. 
   Netpage-specific user identity information is stored on the device during the Netpage registration/activation process. To give the same level of user identity portability as a SIM card the information can be stored on the SIM card, if it is present. If that is not possible, due to a mobile carrier denying access to it or it not being present, it can be stored in a secure store within the device and if that is not possible, on the normal file system of the device. If the identity information is stored on the SIM card, it can automatically move with the user&#39;s carrier identity when they swap SIM cards. 
   6. Use Cases 
   6.1 M-Print Blanks 
   The M-Print printer  4  is able to print on special M-Print blanks that are specially designed to provide optimal print quality in a M-Print printer  4 . The blanks are purchased by a user in packs and loaded one-by-one into the printer when a print is being made. 
   To ensure valid blanks are loaded into the printer  4 , a mechanism for validating the supplied blanks and rejecting imitations can be supplied. This can be done by reading an ID from the blank during printing and validating that ID either locally or via a network service. 
   The blanks are pre-tagged. For Netpage to be able to correctly register a printout an ImpressionlD is determined from the pre-tagged blank when the printout is printed. This implies the M-Print printer is able to read the ImpressionID from the blank. 
   Both cases can use the ID encoded on the blank. The proposed scheme for validating the ID involves reading a second number from the blank called the signature. The signature and ID can then be validated as a pair. 
   The proposed mechanism for this is to consult a network based service that securely stores the ID and signature pairs that have been manufactured. 
   Both the ID and the signature are readable by the printer  4  and in the Netpage case by a Netpage pointer  533 . The M-Print printer  4  does not contain a Netpage pointer  533 , but it includes a bar code reader. This means the ID and the signature are provided on the back of the blank as a linear bar code, most likely in IR ink, for the printer  4  and on the front of the blank encoded in the Netpage tag encoding for the Netpage pointer  533 . 
   In some circumstances, validation of the ID may not be possible in real time before the printout completes. Thus, users are informed if non-genuine blanks are being loaded into the printer and warn the user that loaded non-genuine blanks may decrease the lifetime of the printer&#39;s printhead. 
   While complete validation of the ID may not be possible before printing, coding on the blank can be detected that indicates the orientation of the blank and also the start of the timing codes that allow the printer  4  to detect the speed at which the blank is moving through the printer  4 . If these can not be detected the blank may be rejected before printing commences. 
   6.1.1 Loading a Card 
   Referring to  FIG. 63 , a print job has been submitted to the printer  4 , before it can commence it must be supplied with a valid blank the right way up.
         1. The user is prompted to insert a blank (step  750 )   2. The user inserts a blank (step  751 )       

   If the user inserts the paper upside down at option  752 , the user is prompted to re-insert the blank the other way. If the loaded paper is uncoded or incorrectly coded, the user is prompted to insert a genuine M-Print blank. 
   6.1.2 Validate an ID 
   Referring to  FIG. 64 , during or immediately after printing the printer  4  sends back the ID and possibly the signature of the blank at step  750 . In the background the M-Print services on the mobile device validates the ID at step  757 , either locally at step  759  or via a network service at step  758 , and if the validation fails it informs the user at step  763 . There is a timing issue here in that the user may no longer be looking at the mobile device  100  when the result of validation is known, to alert the user that the blank they have printed on is not valid and that using that media shortens the life of the printhead the M-Print service on the device can deliver the message as a local SMS causing the device to alert the user of a new message. 
   Once the ID and signature have been validated it is passed at step  762  onto a Netpage microserver  761  for processing as the ImpressionID of the printout. The user is alerted that the last print was done on an invalid blank and continuing to use such blanks shortens the life of the printer  4 . 
   6.2 Printing 
   Common to all the use cases present below is printing. From a users perspective, printing normally has two stages, a third may be added if an error occurs or the blank is invalid:
         1. Loading the blank   2. Printing   3. Error reporting       

   The user view of loading the blank and reporting an invalid blank are covered above. The user&#39;s view of printing is both: a progress dialog that allows the user to view the progress of the print and cancel the print; and being able to see the blank move through the printer and emerge from the device. 
   Cancelling the print stops the printer using any more ink, but the ID and signature from the blank may still be read for validation. 
   6.2.1 Print 
   
       
       
         
           1. The user is prompted to load a card. 
           2. A print progress dialogue is displayed, with a cancel button 
           3. The blank is drawn fully through the printer and the print progress dialogue is removed 
         
       
     
  
   If the user wants to cancel the print jobthe user presses cancel on the print progress bar which results in the print job stopping and the blank being ejected. If an error occurs such as a paper jam, an error message may be provided to alert the user. The user may then dismiss the dialog of the error message and progress dialogs are removed. If a blank fails validation, the user is alerted of the failure. 
     FIG. 65  shows a Printer DC  770  as the object that exposes the graphics model used by applications  514  to build up the printed image. It shows the printing following after the application  514  has completed drawing the page. On some systems these operations may overlap or the application  514  may be requested to draw the page multiple times with different clipping regions, eg. rendering in bands, either way the logical flow should still be the same. If capturing all printed documents as Netpage documents is supported then fully composed page is lodged with the Microserver  761 , the Microserver  761  treats this a document lodgement, and records a printout for that document, when the ID and signature are successfully validated and passed onto the microserver  761 . 
     FIG. 65  shows the ID and signature being passed out from the printer  4  soon after printing has commenced, the timing of the transmission of the ID and signature is not significant for the user since they only know about it if the validation fails which occurs after the print has completed. For Netpage enabled printouts, this timing is more critical, since a situation can occur where a printout is immediately handed to another user who clicks on it with a Netpage pointer or pen  733  and expects a result. Where the printing device does not have network connectivity this may not work at all. If the printing device does have network connectivity it still might not work, or at least have a perceivable latency, while the network validation and the ID and registration of the printout is completed. 
   6.3 Uploading and Downloading Data 
   Moving data on and off mobile devices via the wireless network reliably presents a number of challenges:
         1. Wireless networks are inherently unreliable and the link can be lost at any point. This can occur due to signal loss or the mobile device having to disable the radio link to conserver power or to allow another power hungry activity to start up, eg. printing.   2. The bandwidth available on the existing 2.5G networks is limited and it could take up to several minutes to transmit a high resolution photo on or off the device   3. The cost of transferring data over a mobile network can vary and it may be significantly cheaper to delay the transfer to a non-peak time, e.g. late at night.   4. Mobile carriers might prefer non-urgent data transfers to happen during lulls in the network traffic.   5. It may be cost effective to support different means of transferring data. A HTTP Put over GPRS is the most obvious way, but it may be possible to take advantage of carrier price subsidies and send the same data via an MMS or SMS message.       

   Referring to  FIGS. 66 and 67 , to provide flexibility in how data uploading and downloading is achieved and to insulate the rest of the architecture from it, each mobile device  100  has a service responsible for delivering and receiving data from the network. It queues data transfer requests  780  and guarantees delivery of the data in the an efficient manner. It supports partial transfers and resumption of transfers after a break in the data link to minimise the data sent over a wireless network. An equivalent service can be located in the network to both receive data from the mobile device and forward it on to its destinations and also to queue data being sent to the mobile device. 
   The network based component of this service provides a carrier integration point. A carrier may choose to host this service and bill the traffic for it differently to encourage usage of the M-Print and Netpage services. It also provides a single point of modification to take advantage of new features in the carrier networks, eg. a new data push model not based on SMS. 
   The device based component of this service provides a simple interface to the device based M-Print and Netpage services, while providing the ability to exploit all the features of a mobile device  100  to access network based services. This may include taking advantage of WLAN connectivity where possible. 
   The download sequence shown in  FIG. 67  illustrates how “data push” to a mobile device can be achieved which cannot be directly reached from the general internet. It shows a SMS message being sent to the device to inform the download service that there are downloads waiting to be fetched. The message may include some information about the urgency of the downloads, to allow the device side download service to decide when it should fetch the download(s). 
   6.4 Netpage Pointer/Scanner 
   In the printing scenario a blank&#39;s ID is read during printing. This ID is used to both facilitate validation of the blank as a valid M-Print blank and also as an Impression ID for Netpage. The Impression ID is used by the Netpage server  529  to associate the M-Print printout with the document that was printed onto the blank. 
   An M-Print blank has the ID encoded on the back of the blank in a way that is readable by the paper feed mechanism. If the blank has been pre-tagged with Netpage tags then the ID is also embedded in the Netpage tags. To initiate a Netpage interaction the first step is for the user to perform an action that retrieves the ID and supplies it to a Netpage server. The ID can be retrieved by:
         1. A stroke or click with a Netpage Pen;   2. A click with a Netpage Pointer;   3. Scanning the ID on the back of the card.       

   The first two of these actions use Netpage specific devices to read the Netpage tags. The pen  533  provides a stream of digital ink along with the ID and the pointer provides a position on the printout along with the ID. The last uses a scanning mechanism to read the ID from the back of the printout. It can be the same scanner as is used in the M-Print printer paper feed mechanism or it can be a dedicated scanner that the printout is feed into or passed over, similar to a bar code reader. This mechanism only provides the ID, it does not provide any positional information, but Netpage applications can be authored to support a “scan” of the printout as well as a click or a stroke on the printout. 
   6.4.1 Activate a Netpage Application Via a Scan 
   The user passes an existing M-Print printout back through their M-Print printer to activate the associated Netpage application. 
   The printout is drawn through the printer and a Netpage application is launched. If there is no Netpage application for the printout, the user is told the printout has no associated application. If the printout fails validation, the user is alerted of the failure. 
   The effect the user sees as a result of a Netpage application being launched varies depending on the application, some examples are:
         For a photo the use may see the photo displayed on the screen with the option to reprint it or send to someone.   For a business card the user may receive a vCard on their mobile device which can be processed in the normal way.   For a coupon a completed SMS/MMS/email may be displayed asking the user if they wish to send it off to enter the competition.   Any printout may be displayed on the mobile device showing the print image and allowing the user to navigate the hyperlinks and fields in the printout and activate them. If the device has a touch screen, the user can use a pointer to select fields and generate digital ink.       

     FIG. 68  is a sequence fragment that shows the processing of a scanned ID from the paper feed mechanism in the printer. If a scanned ID and signature is returned to the Print Service while it is printing, see  FIG. 65 , it is validated and then passed onto the Netpage Microserver  761  triggering the submission of the Netpage document. The validation is performed by the Print Service  754  in this case to ensure the user can be warned about using invalid media as early as possible. If the Printer Service receives a scanned ID and signature while it is not printing at step  790  then it passes it directly to the Netpage Microserver  761  as a pseudo-click or scan. The Microserver  761  processes it in a similar way to the way it processes a Netpage pointer click. 
   7. Applications 
   7.1 Photo Printing 
   Photo printing is a major application for M-Print. In its simplest form, photo printing can be done completely locally, without any dependence on network services or interactions. Printing a photo can interact with a photo archive. If a photo is printed then it is likely the user may wish to access or print the photo again. When a photo is printed it can be pushed out to the photo archive making it available for on-line retrieval or access. Netpage functionality offers a convenient and natural way of interacting with a printed photo. A Netpage enabled photo can act as a permission token, giving the holder of the printout permission to retrieve and reprint the photo from the archive. Photo archiving from mobile devices is an independent application from photo printing. Users typically take more photos that they wish to keep in an archive than they wish to print. 
   7.1.1 Local Photo Printing 
   Referring to  FIG. 69 , a camera phone user takes a photo at step  795  and elects to print it.
         1. The user uses the default photo application  796  on their device and takes a photo at step  795     2. The user selects print from the applications menu   3. The user is prompted to load a blank   4. The print is produced       

   Other options include:
         The user prints with a border at step  797  by selecting print options from the menu before printing and selects to print with a border, and the user can then select print from the applications menu.   The user requests the date is printed with the photo at step  798  by selecting print options from the menu and selecting the print date and time option, and the user can then select print from the applications menu.   The user adds a caption at step  799  where the user selects photo options from the menu and selects add caption,   wherein the user is prompted to enter a caption and the user selects print from the applications menu.
 
7.1.2 Printing a Photo Archives the Photo
       

   Referring to  FIG. 70 , printing a photo generally implies that the photo has more worth to the user than the photos the user has taken and not printed, it is more likely to be shared and hence more likely to be referred to in an archive. This scenario describes pushing a photo that is printed to the photo archive on the mobile device  100  to give it priority in being transferred off the device  100  and into the archive  800 . 
   When the photo is pushed to the archive the user is given the opportunity to specify what access permission&#39;s should be applied to the photo at step  801  in the archive  800 . In this scenario it is kept to public or private  802  for simplicity, but it could easily be a more complex selection from various ACLs (Access Control Lists) maintained by the user.
         1. The user uses the default photo application  796  on their device  100  and takes a photo.   2. The user may set some print options  801     3. The user selects print from the applications menu  803     4. The user is prompted whether the photo should be public or private in the archive  802     5. The user is prompted to load a blank   6. The print is produced.       

   Optionally, default settings may be applied for archiving the images where the user may not be prompted if the default settings indicate whether all photos should be public or private. 
   This sequence diagram shows the most likely case, where uploading the photo to the archive occurs after printing has finished. This is the most likely case, since power demands of printing require the network connectivity section of the phone to be powered down, or at least avoided. Some devices may be able to support both, in which case the upload could occur during the print. The photo archive is accessible from both a browser on a mobile device  100  or a desktop browser. The user is able to print a photo from the archive to either a desktop printer or the printer in their mobile device. 
   7.1.3 Printing Archives a Netpage Enabled Photo 
   In this use case the user interactions are the same as for “Printing a Photo Archives the Photo”, but in the background, the document, the printout, and the impression ID are registered with the Netpage infrastructure. The printout can be interacted with via a Netpage pointer  533  immediately on the device it was printed on, but it is not be active for other pointers or pens until it has been successfully uploaded to the network based Netpage services. 
   Referring to  FIG. 71 , for Netpage enabled photos that already are being archived in a general purpose photo archive it is not desirable for the Netpage server  529  to also store the photo, so the Netpage server  529  stores a reference to the photo in the archive  800 , allowing it to be retrieved when necessary. The Netpage server  529  still tracks user interactions with the photo: reprints, digital ink, etc but it generally does not store the actual image itself. When the photo is pushed to the archive the pusher receives a reference to the photo that can be used to retrieve the photo when it is required. 
   The need to move the photo and the Netpage document associations out into the network to enable general Netpage interactive on the printed photo, gives the pushing of the photo to the photo archive more importance. In this case the push to the archive includes a flag indicating the photo should be moved to the off device archive as soon as possible. The registering of a printout with the Netpage services can not complete until the blank has been validated since the ID is used as the Netpage impression ID. 
   In this case the photo reference rather than the photo is lodged with the Netpage microserver. The printout can be interacted with via a Netpage pointer on the same device after the ID and signature have been validated, but other pointers and pens can only interact with the document after it has been successfully uploaded to the Netpage network server. 
   8. Player Use Cases 
   8.1 Business Card Application 
   This section covers the Netpage Player PlayRequests  521  used in the interactive Netpage Business Card and describes the behaviour of the Player Agents  537  handling such objects and commands.  FIG. 72  shows the sample business card  810 . The fields (text  811  and images  812 ) are generally associated with PlayRequests  521  that (partially) specify what action is required when a user clicks on one of the fields with a Netpage pointer  533 . 
   8.1.1 Phone Number 
   Referring to  FIG. 73 , the phone number fields  817 ,  818  on the business card  810  are associated with PlayRequests  816 ,  819  that simply specify a phone number, without specifying the operation to be performed or the target of the operation. The author of the business card  810  is thus providing maximum freedom to the receiver of the business card  810  to make use of the phone number fields as they see fit. For example, one user may have their system configured to react to such PlayRequests  816 ,  819  by having their mobile phone dial the specified number, while another user may prefer to have such PlayRequests  816 ,  819  simply pushed to the Netpage Clipboard  615  for later use. 
   The mobile phone icon  813  is configured with a more fully specified PlayRequest  809  than the phone number fields  817 ,  818 . The PlayRequest  809  specifies an operation (“dial” ) that should be performed when that field is selected. The operation overrides the default handling of phone-number values that might otherwise be performed in the absence of an explicit operation. Note that the target of the request is still left unspecified. This gives the routing system the freedom to determine the most appropriate device with which to make the call. This is especially appropriate for a business card  810  which might be handed out to hundreds of users who each typically have their own phone. Placing a specific target in the PlayRequest would have been possible, although inappropriate in this case. The landline telephone icon  813  is configured similarly to the mobile phone icon, but with a different value for the phone number. 
   8.1.2 Fax Number 
   Referring to  FIG. 74 , the Fax phone number field  820  is configured exactly as for the phone number fields except that the phone number value is now also marked as belonging to the “fax” category  823 . This additional information can potentially be used during request routing in order to select targets which specifically cater for “fax” phone numbers rather than targets which simply specify that they cater for phone numbers in general. The “fax” button field  821  specifies an operation (“fax”) in the PlayRequest  822 . The exact semantics of that operation are target dependant. For example, on a mobile phone, the Fax Agent might launch the Fax editor with the destination fax number pre-configured. 
   8.1.3 Web Address 
   Referring to  FIG. 75 , the web URL field  824  and “WWW” icon  825  are configured similarly to the phone number field and phone icons. The icon  825  is specifically configured to cause a web browser to be invoked  826  on the specified URL, whereas the PlayRequest  827  for the URL field is less fully specified and is therefore more flexible in terms of its possible interpretations. 
   8.1.4 SMS and MMS Fields 
   Referring to  FIG. 76 , the “SMS” field  829  is configured to invoke an “SMS” operation  831 . This request could be routed to an SMS Agent running on the user&#39;s mobile phone which would launch the SMS editor with the destination phone number filled in. The “MMS” field  828  is configured similarly to the “SMS” field. 
   8.1.5 Email Address 
   Referring to  FIG. 77 , the web email address field  833  and “Email” icon  832  are configured similarly to the phone number field and phone icons. The icon  832  is specifically configured to perform a “create-email” operation  834 , which can typically be handled routing the request to an agent which is capable of launching email tool with the destination email address pre-configured. The email address field  833  is less fully specified and is therefore more flexible in terms of its possible interpretations. 
   8.1.6 Street Address 
   Referring to  FIG. 78 , the Street Address field  836  is configured to map to a PlayRequest  837  that contains a location value  841  specified using a type of location. The specific details of this type are not specified in this document. The important thing to note is that it stores information that specifies the location in various ways. As such, the value can be handled differently by a large number of agents. Examples might be:
         A Web MAP Search Agent which presents the location in a web browser by accessing a web-based map search facility   A Print Agent on an m-print phone which prints the location details (and possibly directions) on an m-print card.   A GPS Navigator Agent which displays the location in a handheld GPS device.
 
8.1.7 Photo
       

   Referring to  FIG. 79 , the Name field  838  and “Photo” icon  839  are configured to map to a PlayRequest  840  that specifies a jpeg photograph. Typically, this request can be routed to an agent capable of displaying the image. 
   8.2 Scanning Support 
   Referring to  FIG. 80 , interactive Netpage documents can be authored to specify an action upon reception of a scan event. A scan event simply contains the ID of the printed document without any {x,y} coordinate information. In the m-print context, a scan is achieved by feeding a printed card back through the paper feed mechanism. This enables the m-print device to determine the ID of the card and to transmit a scan-hit to the Netpage Server  529 . Upon reception of a scan-hit, the server  529  invokes any scan action that has been registered for the identified printout. 
   The printed business card  820  can be authored to invoke a PlayRequest  851  in response to a scan event. Typically, such a PlayRequest  851  provides information pertaining to the entire content of the printout. In the case of the business card, the document can be authored to invoke a PlayRequest  851  that contains a text/directory object  852  that specifies most of the details from the card. Such a PlayRequest  851  would typically be routed to a Contacts Application (such as vCard Agent) which would then modify its database to include the details from the business card. 
   8.2.1 M-Print Photo Cards Including Scan Support 
     FIG. 81  shows a printed photo card  855 . The card  855  can be made to be interactive as shown in  FIG. 82 . The card  855  contains two fields. The first field is a standard Netpage field  856 , while the second is the scan event field  857 . Both fields  856 ,  857  are configured to map to a PlayRequest  858  that contains the contents of the photo in electronic form (in this case as a jpeg image). Typically, this request  858  is routed to an agent capable of displaying the image, although the fact that the request is only partially specified (the target and operation field are empty) gives the request router (and therefore the user) more freedom to interpret the request as appropriate. For example, previous actions by the user may mean that clicking on the photo is interpreted as a request to associate the photo with a particular location on printed Netpage document. 
   8.3 Printout Interactivity on the Mobile Device GUI 
   When a scan of an M-Print printout is performed on a mobile device  100  the action taken can vary. One possible action is to display the printout on the mobile device&#39;s GUI with the hyperlinks and form fields active so that a user can navigate between them and fill them in or activate them, in the same way a Netpage user can on a printout using a Netpage pen or pointer. 
   If the mobile device has a touch screen and a stylus then it is possible to support all the interactions that a user with a Netpage pen could have with the printout. If the mobile device doesn&#39;t support a touch screen and stylus then it is possible to tab through the hyperlinks and submit fields on the form and activate them in the same way that a user with Netpage pointer and a printout could. 
     FIG. 83  shows a mobile phone  100  where an M-Print printout of a business card  820  has been scanned and the printout is now displayed on the phone&#39;s screen  860  with the first hyperlink  861  highlighted ready to be selected. The user can move through the active areas using standard navigation keys  862  on the mobile device  100 , in the same way they can navigate the hyperlinks on a web page. Selecting a hyperlink in this way via the GUI is the same as clicking a Netpage Pointer  533  on the printout of the business card  820 . 
   Below is a use case illustrating the sequence of events for a user to activate a hyperlink by scanning the printout. 
   8.3.1 Scan a Business Card and Send an MMS to the Person 
   
       
       
         
           1. The user inserts a printout into the paper feed slot on the mobile device ( 870 ) 
           2. The printout is drawn through the mobile device 
           3. The image on the printout is displayed on the mobile device ( 880 ), the first hyperlink has a focus region drawn around it 
           4. The user moves focus to the MMS hyperlink and selects it 
           5. The MMS editor on the device is displayed with the address filled out from the details on the business card ( 890 ). 
         
       
     
  
   The upper portion of the sequence diagram in  FIG. 84  is a repeat of the sequence for the case where a scan is occurring. When the Netpage Microserver receives the “scan click” it retrieves the document and displays it on the screen using the Document Displayer. The Document Displayer allows the user to step through the hyperlinks and fields and select them. When one is selected the Netpage Microserver is sent a click event, just as if it had come from a Netpage pointer. The Netpage processing results in a play request being sent to the Netpage Player on the device, which responds by opening up the MMS editor with the message already addressed to the recipient identified by the business card that was scanned in. 
   9.0 Mobile Telecommunications Device Overview 
   Whilst the main embodiment includes both Netpage and printing functionality, only one or the other of these features is provided in other embodiments. 
   One such embodiment is shown in  FIG. 85 , in which a mobile telecommunications device in the form of a mobile phone  1  (also known as a “cellphone”) includes a mobile phone module  2  and a printer module  4 . The mobile  30  phone module is configured to send and receive voice and data via a telecommunications network (not shown) in a conventional manner known to those skilled in the art. The printer module  4  is configured to print a page  6 . Depending upon the particular implementation, the printer module  4  can be configured to print the page  6  in color or monochrome. 
   The mobile telecommunications device can use any of a variety of known operating systems, such as Symbian (with UIQ and Series 60 GUIs), Windows Mobile, PalmOS, and Linux. 
   In the preferred embodiment (described in more detail below), the print media is pre-printed with tags, and the printer module  4  prints visible information onto the page  6  in registration with the tags. In other embodiments, Netpage tags are printed by the printer module onto the page  6  along with the other information. The tags can be printed using either the same visible ink as used to print visible information, or using an infrared or other substantially invisible ink. 
   The information printed by the printer module  4  can include user data stored in the mobile phone  1  (including 10 phonebook and appointment data) or text and images received via the telecommunications network or from another device via a communication mechanism such as Bluetooth™ or infrared transmission. If the mobile phone  1  includes a camera, the printer module  4  can be configured to print the captured images. In the preferred form, the mobile phone module  2  provides at least basic editing capabilities to enable cropping, filtering or addition of text or other image data to the captured image before printing. The configuration and operation of the printer module  4  is described in more detail below in the context of various types of mobile telecommunication device that incorporate a printhead. 
     FIG. 86  shows another embodiment of a mobile telecommunications device, in which the printer module  4  is omitted, and a Netpage tag sensor module  8  is included. The Netpage module  8  enables interaction between the mobile phone  1  and a page  10  including Netpage tags. The configuration and operation of the Netpage pointer in a mobile phone  1  is described in more detail below. Although not shown, the mobile phone  1  with Netpage module  8  can include a camera. 
     FIG. 87  shows a mobile phone  1  that includes both a printer module  4 , and a Netpage tag sensor module  8 . As with the embodiment of  FIG. 86 , the printer module  4  can be configured to print tagged or untagged pages. As shown in  FIG. 87 , where tagged pages  10  are produced (and irrespective of whether the tags were pre-printed or printed by the printer module  4 ), the Netpage tag sensor module  8  can be used to interact with the resultant printed media. 
   A more detailed architectural view of the mobile phone  1  of  FIG. 87  is shown in  FIG. 88 , in which features corresponding to those shown in  FIG. 87  are indicated with the same reference numerals. It will be appreciated that  FIG. 88  deals only with communication between various electronic components in the mobile telecommunications device and omits mechanical features. These are described in more detail below. 
   The Netpage tag sensor module  8  includes a monolithically integrated Netpage image sensor and processor  12  that captures image data and receives a signal from a contact switch  14 . The contact switch  14  is connected to a nib (not shown) to determine when the nib is pressed into contact with a surface. The sensor and processor  12  also outputs a signal to control illumination of an infrared LED  16  in response to the stylus being pressed against the surface. The image sensor and processor  12  outputs processed tag information to a Netpage pointer driver  18  that interfaces with the phone operating system  20  running on the mobile telecommunications device&#39;s processor (not shown). 
   Output to be printed is sent by the phone operating system  20  to a printer driver  22 , which passes it on to a MoPEC chip  24 . The MoPEC chip processes the output to generate dot data for supply to the printhead  26 , as described in more detail below. The MoPEC chip  24  also receives a signal from a media sensor  28  indicating when the media is in position to be printed, and outputs a control signal to a media transport  30 . The printhead  26  is disposed within a replaceable cartridge  32 , which also includes ink  34  for supply to the printhead. 
   9.1 Mobile Telecommunications Device Module 
     FIG. 89  shows the mobile phone module  2  in more detail. The majority of the components other than those directly related to printing and Netpage tag sensing are standard and well known to those in the art. Depending upon the specific implementation of the mobile phone  1 , any number of the illustrated components can be included as part of one or more integrated circuits. 
   Operation of, and communication between, the mobile phone module  2  components is controlled by a mobile phone controller  36 . The components include:
         mobile radio transceiver  38  for wireless communication with a mobile telecommunications network;   program memory  40  for storing program code for execution on the mobile phone controller  36 ;   working memory  42  for storing data used and generated by the program code during execution. Although shown as separate from the mobile phone controller  36 , either or both memories  40  and  42  may be incorporated in the package or silicon of the controller;   keypad  44  and buttons  46  for accepting numerical and other user input;   touch sensor  48  which overlays display  50  for accepting user input via a stylus or fingertip pressure;   removable memory card  52  containing non-volatile memory  54  for storing arbitrary user data, such as digital photographs or files;   local area radio transceiver  56 , such as a Bluetoothrm transceiver;   GPS receiver  58  for enabling determination of the location of the mobile telecommunications device (alternatively the phone may rely on mobile network mechanisms for determining its location);   microphone  60  for capturing a user&#39;s speech;   speaker  62  for outputting sounds, including voice during a phone call;   camera image sensor  64  including a CCD for capturing images;   camera flash  66 ;   power manager  68  for monitoring and controlling power consumption of the mobile telecommunications device and its components; and   SIM (subscriber Identity Module) card  70  including SIM  72  for identifying the subscriber to mobile networks.       

   The mobile phone controller  36  implements the baseband functions of mobile voice and data communications protocols such as GSM, GSM modem for data, GPRS and CDMA, as well as higher-level messaging protocols such as SMS and MMS. The one or more local-area radio transceivers  56  enable wireless communication with peripherals such as headsets and Netpage pens, and hosts such as personal computers. The mobile phone controller  36  also implements the baseband functions of local-area voice and data communications protocols such as IEEE 802.11, IEEE 802.15, and Bluetooth™. 
   The mobile phone module  2  may also include sensors and/or motors (not shown) for electronically adjusting zoom, focus, aperture and exposure in relation to the digital camera. Similarly, as shown in  FIG. 90 , components of the printer module  4  include:
         print engine controller (PEC)  74  in the form of a MoPEC device;   program memory  76  for storing program code for execution by the print engine controller  74 ;   working memory  78  for storing data used and generated by the program code during execution by the print engine controller  74 ; and   a master QA chip  80  for authenticating printhead cartridge  32  via its QA chip  82 .       

   Whilst the printhead cartridge in the preferred form includes the ink supply  34 , the ink reservoirs can be housed in a separate cartridge in alternative embodiments. 
     FIG. 91  shows the components of the tag sensor module  8 , which includes a CMOS tag image processor  74  that communicates with image memory  76 . A CMOS tag image sensor  78  sends captured image data to the processor  74  for processing. The contact sensor  14  indicates when a nib (not shown) is brought into contact with a surface with sufficient force to close a switch within the contact sensor  14 . Once the switch is closed, the infrared LED  16  illuminates the surface, and the image sensor  78  captures at least one image and sends it to the image processor  74  for processing. Once processed (as described below in more detail), image data is sent to the mobile phone controller  36  for decoding. 
   In an alternative embodiment, shown in  FIG. 92 , the tag sensor module  8  is replaced by a tag decoder module  81 . The tag decoder module  81  includes all the elements of the tag sensor module  8 , but adds a hardware-based tag decoder  82 , as well as program memory  84  and working memory  86  for the tag decoder. This arrangement reduces the computational load placed on the mobile phone controller, with a corresponding increase in chip area compared to using the tag sensor module  8 . 
   The Netpage sensor module can be incorporated in the form of a Netpage pointer, which is a simplified Netpage pen suitable mostly for activating hyperlinks. It preferably incorporates a non-marking stylus in place of the pen&#39;s marking nib (described in detail later in the specification); it uses a surface contact sensor in place of the pen&#39;s continuous force sensor; and it preferably operates at a lower position sampling rate, making it unsuitable for capturing drawings and hand-writing. A Netpage pointer is less expensive to implement than a Netpage pen, and tag image processing and tag decoding can potentially be performed by software without hardware support, depending on sampling rate. 
   The various aspects of the invention can be embodied in any of a number of mobile telecommunications device types. Several different devices are described here, but in the interests of brevity, the detailed description will concentrate on the mobile telecommunications device embodiment. 
   9.2 Mobile Device 
   One preferred embodiment is the non-Netpage enabled ‘candy bar’ mobile telecommunications device in the form of a mobile phone shown in  FIGS. 92 to 98 . While a candy bar style phone is described here, it could equally take the form of a “flip” style phone, which includes a pair of body sections that are hinged to each other. Typically, the display is disposed on one of the body sections, and the keypad is disposed on the other, such that the display and keypad are positioned adjacent to each other when the device is in the closed position. 
   In further embodiments, the device can have two body sections that rotate or slide relative to each other. Typically, the aim of these mechanical relationships between first and second body sections is to protect the display from scratches and/or the keypad from accidental activation. Photo printing is considered one of the most compelling uses of the mobile Memjet printer. A preferred embodiment of the invention therefore includes a camera, with its attendant processing power and memory capacity. 
   The elements of the mobile telecommunications device are best shown in  FIG. 93 , which (for clarity) omits minor details such as wires and hardware that operatively connect the various elements of the mobile telecommunications device together. The wires and other hardware will be well known to those skilled in the art. The mobile phone  100  comprises a chassis moulding  102 , a front moulding  104  and a rear cover moulding  106 . A rechargeable battery  108 , such as a lithium ion or nickel metal hydride battery, is mounted to the chassis moulding  102  and covered by the rear cover moulding  106 . The battery  108  powers the various components of the mobile phone  100  via battery connector  276  and the-camera and speaker connector  278 . 
   The front moulding  104  mounts to the emphasis to enclose the various components, and includes numerical interface buttons  136  positioned in vertical rows on each side of the display  138 . A multi-directional control pad  142  and other control buttons  284  enable menu navigation and other control inputs. A daughterboard  280  is mounted to the chassis moulding  102  and includes a directional switch  286  for the multi directional control pad  142 . The mobile telecommunications device includes a cartridge access cover  132  that protects the interior of the mobile telecommunications device from dust and other foreign objects when a print cartridge  148  is not inserted in the cradle  124 . 
   An optional camera module  110  is also mounted to the chassis moulding  102 , to enable image capture through a hole  112  in the rear cover moulding  106 . The camera module  110  includes a lens assembly and a CCD image sensor for capturing images. A lens cover  268  in the hole  112  protects the lens of the camera module  110 . The rear cover moulding  106  also includes an inlet slot  228  and an outlet slot  150  through which print media passes. 
   The chassis moulding  102  supports a data/recharge connector  114 , which enables a proprietary data cable to be plugged into the mobile telecommunications device for uploading and downloading data such as address book information, photographs, messages, and any type of information that might be sent or received by the mobile telecommunications device. The data/recharge connector  114  is configured to engage a corresponding interface in a desktop stand (not shown), which holds the mobile telecommunications device in a generally upright position whilst data is being sent or received by the mobile telecommunications device. The data/recharge connector also includes contacts that enable recharging of the battery  108  via the desktop stand. A separate recharge socket  116  in the data/recharge connector  114  is configured to receive a complimentary recharge plug for enabling recharging of the battery when the desktop stand is not in use. 
   A microphone  170  is mounted to the chassis moulding  102  for converting sound, such as a user&#39;s voice, into an electronic signal to be sampled by the mobile telecommunications device&#39;s analog to digital conversion circuitry. This conversion is well known to those skilled in the art and so is not described in more detail here. A SIM (Subscriber Identity Module) holder  118  is formed in the chassis moulding  102 , to receive a SIM card  120 . The chassis moulding is also configured to support a print cartridge cradle  124  and a drive mechanism  126 , which receive a replaceable print cartridge  148 . These features are described in more detail below. Another moulding in the chassis moulding  102  supports an aerial (not shown) for sending and receiving RF signals to and from a mobile telecommunications network. 
   A main printed circuit board (PCB)  130  is supported by the chassis moulding  102 , and includes a number of momentary pushbuttons  132 . The various integrated and discrete components that support the communications and processing (including printing processing) functions are mounted to the main PCB, but for clarity are not shown in the diagram. 
   A conductive elastomeric overlay  134  is positoned on the main PCB  130  beneath the keys  136  on the front  40  moulding  104 . The elastomer incorporates a carbon impregnated pill on a flexible profile. When one of the keys  136  is pressed, it pushes the carbon pill to a 2-wire open circuit pattern  132  on the PCB surface. This provides a low impedance closed circuit. Alternatively, a small dome is formed on the overlay corresponding to each key  132 . 
   Polyester film is screen printed with carbon paint and used in a similar manner to the carbon pills. Thin adhesive film with berrylium copper domes can also be used. A loudspeaker  144  is installed adjacent apertures  272  in the front moulding  104  to enable a user to hear sound such as voice communication and other audible signals. 
   A color display  138  is also mounted to the main PCB  130 , to enable visual feedback to a user of the mobile telecommunications device. A transparent lens moulding  146  protects the display  138 . In one form, the transparent lens is touch-sensitive (or is omitted and the display  138  is touch sensitive), enabling a user to interact with icons and input text displayed on the display  138 , with a finger or stylus. 
   A vibration assembly  274  is also mounted to the chassis moulding  102 , and includes a motor that drives an eccentrically mounted weight to cause vibration. The vibration is transmitted to the chassis  102  and provides tactile feedback to a user, which is useful in noisy environments where ringtones are not audible. 
   10. Print Media Printing 
   A Netpage printer normally prints the tags which make up the surface coding on demand, i.e. at the same time as it prints graphic page content. As an alternative, in a Netpage printer not capable of printing tags such as the preferred embodiment, pre-tagged but otherwise blank Netpages can be used. The printer, instead of being capable of tag printing, typically incorporates a Netpage tag sensor. The printer senses the tags and hence the region ID of a blank either prior to, during, or after the printing of the graphic page content onto the blank. It communicates the region ID to the Netpage server, and the server associates the page content and the region ID in the usual way. 
   A particular Netpage surface coding scheme allocates a minimum number of bits to the representation of spatial coordinates within a surface region. If a particular media size is significantly smaller than the maximum size representable in the minimum number of bits, then the Netpage code space may be inefficiently utilised. It can therefore be of interest to allocate different sub-areas of a region to a collection of blanks. Although this makes the associations maintained by the Netpage server more complex, and makes subsequent routing of interactions more complex, it leads to more efficient code space utilisation. In the limit case the surface coding may utilise a single region with a single coordinate space, i.e. without explicit region IDs. 
   If regions are sub-divided in this way, then the Netpage printer uses the tag sensor to determine not only the region ID but also the surface coding location of a known physical position on the print medium, i.e. relative to two edges of the medium. From the surface coding location and its corresponding physical position on the medium, and the known (or determined) size of the medium, it then determines the spatial extent of the medium in the region&#39;s coordinate space, and communicates both the region ID and the spatial extent to the server. The server associates the page content with the specified sub-area of the region. 
   A number of mechanisms can be used to read tag data from a blank. A conventional Netpage tag sensor incorporating a two-dimensional image sensor can be used to capture an image of the tagged surface of the blank at any convenient point in the printer&#39;s paper path. As an alternative, a linear image sensor can be used to capture successive line images of the tagged surface of the blank during transport. The line images can be used to create a two-dimensional image which is processed in the usual way. As a further alternative, region ID data and other salient data can be encoded linearly on the blank, and a simple photodetector and ADC can be used to acquire samples of the linear encoding during transport. 
   One important advantage of using a two-dimensional image sensor is that tag sensing can occur before motorised transport of the print medium commences. For example, if the print medium is manually inserted by the user, then tag sensing can occur during insertion. This has the further advantage that if the tag data is validated by the device, then the print medium can be rejected and possibly ejected before printing commences. For example, the print medium may have been pre-printed with advertising or other graphic content on the reverse side from the intended printing side. The device can use the tag data to detect incorrect media insertion, i.e. upside-down or back-to-front. The device can also prevent accidental overprinting of an already-printed medium. And it can detect the attempted use of an invalid print medium and refuse printing, eg. to protect print quality. The device can also derive print medium characteristics from the tag data, to allow it to perform optimal print preparation. 
   If a linear image sensor is used, or if a photodetector is used, then image sensing must occur during motorised transport of the print medium to ensure accurate imaging. Unless there are at least two points of contact between the transport mechanism and the print medium in the printing path, separated by a minimum distance equal to the tag data acquisition distance, tag data cannot be extracted before printing commences, and the validation advantages discussed above do not obtain. In the case of a linear image sensor, the tag data acquisition distance equals the diameter of the normal tag imaging field of view. In the case of a photodetector, the tag data acquisition distance is as long as the required linear encoding. 
   If the tag sensor is operable during the entire printing phase at a sufficiently high sampling rate, then it can also be used to perform accurate motion sensing, with the motion data being used to provide a line synchronisation signal to the print engine. This can be used to eliminate the effects of jitter in the transport mechanism. 
     FIGS. 100 to 106  show one embodiment of the encoded medium and the media sensing and printing system within the mobile telecommunications device. While the encoding of the cards is briefly discussed here, it is described in detail in the Coded Media sub-section of this specification. 
   Referring to  FIG. 100 , the ‘back-side’ of one of the cards  226  is shown. The back-side of the card has two coded data tracks: a ‘clock track’  434  and a ‘data track’  436  running along the longitudinal sides of the cards. The coded data may be in the form of a two-dimensional grid or pattern. The cards are encoded with data indicating, inter alia:
         the orientation of the card;   the media type and authenticity;   the longitudinal size;   the pre-printed side;   detection of prior printing on the card; and,   the position of the card relative to the printhead IC.       

   In one form, the encoded data is printed in IR ink so that it is invisible and does not encroach on the space available for printing visible images. 
   In a basic form, the M-Print cards  226  are only encoded with a data track and clocking (as a separate clock track or a self-clocking data track). However, in the more sophisticated embodiment shown in the figures, the cards  226  have a pre-printed Netpage tag pattern  438  covering the majority of the back-side. The front side may also have a pre-printed tag pattern. It is preferred in these embodiments that the data track encodes first information that is at least indicative of second information encoded in the tags. Most preferably, the first information is simply the document identity that is encoded in each of the tags. 
   The clock track  434  allows the MoPEC  326  (see  FIG. 101 ) to determine, by its presence, that the front of the card  226  is facing the printhead  202 , and allows the printer to sense the motion of the card  226  during printing. The clock track  434  also provides a clock for the densely coded data track  436 . 
   The data track  436  provides the Netpage identifier and optionally associated digital signatures which allows MoPEC  326  to reject fraudulent or un-authorised media  226 , and to report the Netpage identifier of the front-side Netpage tag pattern to a Netpage server. It should be noted that a fragment of a digital signature can also be considered a digital signature in its own right. 
     FIG. 101  shows a block diagram of an M-Print system that uses media encoded with separate clock and data tracks. The clock and data tracks are read by separate optical encoders. The system may optionally have an explicit edge detector  474  which is discussed in more detail below in relation to  FIG. 104 . 
     FIG. 102  shows a simplified circuit for an optical encoder which may be used as the clock track or data track optical encoder. It incorporates a Schmitt trigger  466  to provide the MoPEC  326  with an essentially binary signal representative of the marks and spaces encountered by the encoder in the clock or data track. An IR LED  472  is configured to illuminate a mark-sized area of the card  226  and a phototransistor  468  is configured to capture the light  470  reflected by the card. The LED  472  has a peak wavelength matched to the peak absorption wavelength of the infrared ink used to print the media coding. 
   As an alternative, the optical encoders can sense the direction of media movement by configuring them to be ‘quadrature encoders’. A quadrature encoder contains a pair of optical encoders spatially positioned to read the clock track 90 degrees out of phase. Its in-phase and quadrature outputs allow the MoPEC  326  to identify not just the motion of the clock track  434  but also the direction of the motion. A quadrature encoder is generally not required, since the media transport direction is known a priori because the printer controller also controls the transport motor. However, the use of a quadrature encoder can help decouple a bi-directional motion sensing mechanism from the motion control mechanism. 
     FIG. 103  shows a block diagram of the MoPEC  326 . It incorporates a digital phase lock loop (DPLL)  444  to track the clock inherent in the clock track  434  (see  FIG. 100 ), a line sync generator  448  to generate the line sync signal  476  from the clock  446 , and a data decoder  450  to decode the data in the data track  436 . De-framing, error detection and error correction may be performed by software running on MoPEC&#39;s general-purpose processor  452 , or it may be performed by dedicated hardware in MoPEC. 
   The data decoder  450  uses the clock  446  recovered by the DPLL  444  to sample the signal from the data track optical encoder  442 . It may either sample the continuous signal from the data track optical encoder  442 , or it may actually 5
         trigger the LED of the data track optical encoder  442  for the duration of the sample period, thereby reducing the total power consumption of the LED. The DPLL  444  may be a PLL, or it may simply measure and filter the period between successive clock pulses.       

   The line sync generator  456  consists of a numerically-controlled oscillator which generates line sync pulses  476  at a rate which is a multiple of the rate of the clock  446  recovered from the clock track  434 . 
   As shown in  FIG. 101 , the print engine may optionally incorporate an explicit edge detector  474  to provide longitudinal registration of the card  226  with the operation of the printhead  202 . In this case, as shown in  FIG. 104 , it generates a page sync signal  478  to signal the start of printing after counting a fixed number of line syncs  476  after edge detection. Longitudinal registration may also be achieved by other card-in detection mechanisms ranging from opto-sensors, de-capping mechanical switches, drive shaft/tension spring contact switch and motor load detection. 
   Optionally, the printer can rely on the media coding itself to obtain longitudinal registration. For example, it may rely on acquisition of a pilot sequence on the data track  436  to obtain registration. In this case, as shown in  FIG. 105 , it generates a page sync signal  478  to signal the start of printing after counting a fixed number of line syncs  476  after pilot detection. The pilot detector  460  consists of a shift register and combinatorial logic to recognise the pilot sequence  480  provided by the data decoder  450 , and generate the pilot sync signal  482 . Relying on the media coding itself can provide superior information for registering printed content with the Netpage tag pattern  438  ( FIG. 100 ). 
   As shown in  FIG. 106 , the data track optical encoder  442  is positioned adjacent to the first clock data encoder  440 , so that the data track  436  (see  FIG. 100 ) can be decoded as early as possible and using the recovered clock signal  446 . The clock must be acquired before printing can commence, so a first optical encoder  440  is positioned before the printhead  202  in the media feed path. However, as the clock needs to be tracked throughout the print, a second clock optical encoder  464  is positioned coincident with or downstream of the printhead  202 . This is described in more detail below. 
     FIG. 99  shows the printed card  226  being withdrawn from the print cartridge,  148 . It will be appreciated that the printed card  226  needs to be manually withdrawn by the user. Once the trailing edge of the card  226  has passed between the drive shaft  178  and the spring fingers  238 , it is no longer driven along the media feed path. However, as the printhead  202  is less than 2 mm from the drive shaft  178 , the momentum of the card  226  projects the trailing edge of past the printhead  202 . 
   While the momentum of the card is sufficient to carry the trailing edge past the printhead, it is not enough to fling it out of the exit slot  150  ( FIG. 98 ). Instead, the card  226  is lightly gripped by the opposed lock actuator arms  232  a protrudes from the exit slot  150  in the side of the mobile phone  100 . This retains the card  226  so it does not simply fall from exit slot  150 , but rather allows users to manually remove the printed card  226  from the mobile phone  100  at their convenience. This is important to the practicality of the mobile telecommunications device because the card  226  is fed into one side of the mobile telecommunications device and retrieved from the other, so users will typically want to swap the hand that holds the mobile telecommunications device when collecting the printed card. By lightly retaining the printed card, users do not need to swap hands and be ready to collect the card before completion of the print job (approximately 1-2 secs). Alternatively, the velocity of the card as it leaves the roller can be made high enough that the card exits the outlet slot  123  under its own inertia. 
   10.1 M-Print Flip Printing 
   One can allow a previously printed m-print Netpage card to be re-inserted into the printing mechanism “flipped-over”, so that the side not previously printed on (i.e. the back of the card) is now facing towards the print head. The printer would detect such an insertion and would automatically print additional information on to the back of the card. The additional information would typically, but not necessarily, be application and context specific. That is:
         the application which created the original printout would determine what is printed onto the back side of the card, and   would be able to take into account context specific information such as the impression ID of the card.       

   This allows applications to print information onto the back side of the card which is specific to the original printout on the front side of the card. There are many potential uses for such a mechanism. For the sake of discussion, one such case is described below. 
   10.1.1 Camera Use-Case 
   
       
       
         
           1. User takes a photo using an m-print enabled camera phone 
           2. User prints photo onto Netpage tagged card 
           3. User feeds card back through printer flipped-over 
           4. Various details about the photo would then be printed onto the back of the card. Examples of details might be:
           The date and time the photo was taken;   Location where photo was taken, either automatically determined by a geographical positioning system within the phone (eg. GPS or cell-based location detection), or manually entered after the fact by the user; and/or   Arbitrary textual information entered by the user (perhaps entered on the phone itself or via a web-based photo archiving application sometime after the photo was taken).   
         
         
       
     
  
   The time duration between the user taking the original photo and inserting the flipped-over card could be arbitrarily long. As such, the mechanism can act as a “what is this photo that I just found?” facility. Another advantage is that it removes the need to have text obscuring parts of the photo in order to provide date/time information. 
   11. General Netpage Overview 
   Netpage interactivity can be used to provide printed user interfaces to various phone functions and applications, such as enabling particular operational modes of the mobile telecommunications device or interacting with a calculator application, as well as providing general “keypad”, “keyboard” and “tablet” input to the mobile telecommunications device. Such interfaces can be pre-printed and bundled with a phone, purchased separately (as a way of customizing phone operation, similar to ringtones and themes) or printed on demand where the phone incorporates a printer. 
   A printed Netpage business card provides a good example of how a variety of functions can be usefully combined in single interface, including:
         loading contact details into an address book
           displaying a Web page   displaying an image   dialing a contact number   bringing up an e-mail, SMS or MMS form   loading location info into a navigation system   activating a promotion or special offer   
               

   Any of these functions can be made single-use only. A business card may be printed by the mobile telecommunications device user for presentation to someone else, or may be printed from a Web page relating to a business for the mobile telecommunications device user&#39;s own use. It may also be pre-printed. 
   As described below, the primary benefit of incorporating a Netpage pointer or pen in another device is synergy. A Netpage pointer or pen incorporated in a mobile phone, smartphone or telecommunications-enabled PDA, for example, allows the device to act as both a Netpage pointer and as a relay between the pointer and the mobile phone network and hence a Netpage server. When the pointer is used to interact with a page, the target application of the interaction can display information on the phone display and initiate further interaction with the user via the phone touchscreen. The pointer is most usefully configured so that its “nib” is in a corner of the phone body, allowing the user to easily manipulate the phone to designate a tagged surface. The phone can incorporate a marking nib and optionally a continuous force sensor to provide full Netpage pen functionality. 
   An exemplary Netpage interaction will now be described to show how a sensing device in the form of a Netpage enabled mobile device interacts with the coded data on a print medium in the form of a card. Whilst in the preferred form the print. medium is a card generated by the mobile device or another mobile device, it can also be a commercially pre-printed card that is purchased or otherwise provided as part of a commercial transaction. The print medium can also be a page of a book, magazine, newspaper or brochure, for example. The print medium can be provided with coded data in a variety of formats, the coded data encoding a range of information, preferably, at least some of the information being indicative of the print media identifier. The information can be indicative of a two-dimensional coordinate grid, and the format can be a two-dimensional pattern. 
   For example, the print medium can be provided with first coded data in a first format and second coded data in a second format, the first coded data encoding first information and the second coded data encoding second information, with at least some of the first information being indicative of the print media identifier, the first format being a linear pattern, and with at least some of the second information being indicative of the print media identifier and of a two-dimensional coordinate grid, the second format being a two-dimensional pattern. In a particular example form, the information is further indicative of at least part of a digital signature associated with the print media identifier, the sensor module determining, by reading at least some of the coded data, at least part of the digital signature, and the printer module can then print, if the digital signature is authentic, content on the print media. 
   The mobile device senses a tag using an area image sensor and detects tag data. The mobile device uses the sensed data tag to generate interaction data, which is sent via a mobile telecommunications network to a document server. The document server uses the ID to access the document description, and interpret the interaction. In appropriate circumstances, the document server sends a corresponding message to an application server, which can then perform a corresponding action. 
   Typically Netpage pen and Netpage-enabled mobile device users register with a registration server, which associates the user with an identifier stored in the respective Netpage pen or Netpage enabled mobile device. By providing the sensing device identifier as part of the interaction data, this allows users to be identified, allowing transactions or the like to be performed. Netpage documents are generated by having an ID server generate an ID which is transferred to the document server. The document server determines a document description and then records an association between the document description and the ID, to allow subsequent retrieval of the document description using the ID. The ID is then used to generate the tag data, as will be described in more detail below, before the document is printed by a suitable printer, using the page description and the tag map. 
   Each tag is represented by a pattern which contains two kinds of elements. The first kind of element is a target. Targets allow a tag to be located in an image of a coded surface, and allow the perspective distortion of the tag to be inferred. The second kind of element is a macrodot. Each macrodot encodes the value of a bit by its presence or absence. The pattern is represented on the coded surface in such a way as to allow it to be acquired by an optical imaging system, and in particular by an optical system with a narrowband response in the near-infrared. The pattern is typically printed onto the surface using a narrowband near-infrared ink. 
   In the preferred embodiment, the region typically corresponds to the entire surface of an M-Print card, and the region ID corresponds to the unique M-Print card ID. For clarity in the following discussion we refer to items and IDs, with the understanding that the ID corresponds to the region ID. The surface coding is designed so that an acquisition field of view large enough to guarantee acquisition of an entire tag is large enough to guarantee acquisition of the ID of the region containing the tag. Acquisition of the tag itself guarantees acquisition of the tag&#39;s two-dimensional position within the region, as well as other tag-specific data. The surface coding therefore allows a sensing device to acquire a region ID and a tag position during a purely local interaction with a coded surface, e.g. during a “click” or tap on a coded surface with a pen. 
   Optional embodiments of the present invention may also be said to broadly consist in the parts, elements and features referred to or indicated herein, individually or collectively, in any or all combinations of two or more of the parts, elements or features, and wherein specific integers are mentioned herein which have known equivalents in the art to which the invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth. 
   Although a preferred embodiment has been described in detail, it should be understood that various changes, substitutions, and alterations can be made by one of ordinary skill in the art without departing from the scope of the present invention.