Abstract:
A technique is presented for making effective use of sheets when the total number of pages to be printed on a sheet is changed after the number of pages per sheet was originally specified. In one aspect, the technique is implemented on an apparatus that accepts a specified number of pages per sheet, obtains a page group having a number of pages, determines whether the number of pages in the page group has changed, changes the specified number of pages per sheet when the number of pages in the page group has changed, and generates output data of the pages with the specified number of pages when the number of pages in the page group has not been changed, and generates the changed number of pages when the number has been changed.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to Japanese Patent Application No. 2011-288735, filed on Dec. 28, 2011, which is incorporated herein by reference. 
       TECHNICAL FIELD 
       [0002]    Aspects of the disclosure relate to a technique for laying out a plurality of pages in one or more sheets. 
       BACKGROUND 
       [0003]    In a known technique, when a page is deleted from N pages to be laid out on one side of a sheet while a size of each page is reduced, one or more pages following the deleted page are moved up in the current layout order. When a blank page is inserted somewhere between two pages of N pages to be laid out in the same situation, one or more pages following the blank page are moved back in the current layout order. 
       SUMMARY 
       [0004]    However, when the total number of pages, e.g., N pages, is changed due to the deletion or addition of one or more pages, wasted space may appear on the sheet or the number of sheets to be used may increase. 
         [0005]    Aspects of the disclosure provide for a technique for making effective use of sheets when the total number of pages to be printed is changed after the number of pages per sheet was specified. 
         [0006]    An novel information processing apparatus is presented. The apparatus is configured to accept a specified of a number of pages per sheet laid out on one sides of a sheet; obtain a page group including one or more pages; determine whether a total number of pages in the page group has been changed; change the specified number of pages per sheet when the total number of pages in the page group has been changed; generate output data of the pages included in the page group in which the pages are laid out on each of one or more sheets in accordance with the specified number of pages per sheet, when the total number of pages in the page group has not been changed; and generate output data of the pages included in the page group in which the pages are laid out on each of one or more sheets in accordance with the changed number of pages per sheet, when the total number of pages in the page group has been changed. 
         [0007]    In one aspect, at least one page is deleted from the page group after the number of pages per sheet are specified; and the specified number of pages per sheet is reduced when the at least one page is deleted. In one aspect, a first size of each page in the page group that is to be laid out on each of the one or more sheets in accordance with the specified number of pages per sheet is calculated; a second size of each page in the page group that is to be laid out on each of the one or more sheets in accordance with the reduced number of pages per sheet is calculated; it is determined whether the second size is smaller than the first size; and the specified number of pages per sheet is used when the second size is smaller than the first size whether or not the at least one page is deleted. In one aspect, a first number of sheets is obtained to be used when the pages remaining in the page group from which the at least one page has been deleted are laid out by using the reduced number of pages per sheet; a second number of sheets is obtained to be used when the pages included in the page group from which no page has been deleted are laid out by using the specified number of pages per sheet; and the specified number of pages per sheet is reduced such that the first number of the sheets to be used does not exceed the second number of the sheets to be used. 
         [0008]    In one aspect, a first number of sheets is obtained to be used when the pages remaining in the page group from which the at least one page has been deleted are laid out by using the reduced number of pages per sheet; a second number of sheets is obtained to be used when the pages remaining in the page group from which the at least one page has been deleted are laid out by using the specified number of pages per sheet; and the specified number of pages per sheet is reduced such that the first number of the sheets to be used does not exceed the second number of the sheets to be used. In one aspect, a selection of one of a first changing method and a second changing method is accepted, wherein the first changing method is a method of changing the specified number of pages per sheet to another number of pages per sheet smaller than the specified number of pages per sheet such that a number of sheets to be used when the pages remaining in the page group from which the at least one page has been deleted are laid out by using the another number of pages per sheet does not exceed a number of sheets to be used when the pages included in the page group from which no page has been deleted are laid out by using the specified number of pages per sheet, and the second changing method is a method of changing the specified number of pages per sheet to another number of pages per sheet smaller than the specified number of pages per sheet such that a number of sheets to be used when the pages remaining in the page group from which the at least one page has been deleted are laid out by using the another number of pages per sheet does not exceed a number of sheets to be used when the pages remaining in the page group from which the at least one page has been deleted are laid out by using the specified number of pages per sheet; and the specified number of pages per sheet by using the selected changing method is changed. In one aspect, a selection is accepted of one of a single-sided layout in which the pages are laid out on one side of each of the one or more sheets and a double-sided layout in which the pages are laid out on both sides of each of the one or more sheets; and when the double-sided layout is selected, the number of pages per sheet such that one or more of the pages are laid out on the other side of the last sheet of the one or more sheets is changed. In one aspect, whether a colorant consumption in printing of the pages included in the page group needs to be saved is determined; and the specified number of pages per sheet when the colorant consumption in printing of the pages included in the page group needs to be saved whether or not the total number of pages in the page group has been changed is used. In one aspect, when executed, further cause the information processing apparatus to perform changing the total number of pages in the page group after the number of pages per sheet are specified. In one aspect, printing the output data is performed using one or more of a printer, a copying machine, a facsimile machine, and a scanner. 
         [0009]    The one or more aspects of the disclosure may be accomplished in various manners, such as using image processing devices, page layout methods, or computer-readable storage medium storing page layout programs. 
         [0010]    According to the one or more aspects of the disclosure, a sheet may be effectively used although the total number of pages to be printed is changed after the number of pages per sheet was specified. 
         [0011]    Other objects, features, and advantages will be apparent to persons of ordinary skill in the art from the following detailed description of the disclosure and the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    For a more complete understanding of the present disclosure, and the objects, features, and advantages thereof, reference now is made to the following descriptions taken in connection with the accompanying drawing. 
           [0013]      FIG. 1  is a block diagram depicting an electrical configuration of a personal computer in a first illustrative embodiment according to one or more aspects of the disclosure. 
           [0014]      FIG. 2  is a schematic diagram depicting a print screen and a print condition setting screen in the first illustrative embodiment according to one or more aspects of the disclosure. 
           [0015]      FIG. 3  is a schematic diagram for explaining the number of pages per sheet in the first illustrative embodiment according to one or more aspects of the disclosure. 
           [0016]      FIG. 4  is a schematic diagram depicting an example of a preview screen in the first illustrative embodiment according to one or more aspects of the disclosure. 
           [0017]      FIG. 5  is a schematic diagram illustrating a first changing method when single-sided printing is specified in the first illustrative embodiment according to one or more aspects of the disclosure. 
           [0018]      FIG. 6  is a diagram illustrating the first changing method when double-sided printing is specified in the first illustrative embodiment according to one or more aspects of the disclosure. 
           [0019]      FIG. 7  is a diagram illustrating a second changing method when single-sided printing is specified in the first illustrative embodiment according to one or more aspects of the disclosure. 
           [0020]      FIG. 8  is a schematic diagram illustrating the second changing method when double-sided printing is specified in the first illustrative embodiment according to one or more aspects of the disclosure. 
           [0021]      FIG. 9  is a diagram illustrating a case where the number of pages per sheet is not changed although the total number of pages in a page group is changed in the first illustrative embodiment according to one or more aspects of the disclosure. 
           [0022]      FIG. 10  is a flowchart depicting a printing process in the first illustrative embodiment according to one or more aspects of the disclosure. 
           [0023]      FIG. 11  is a flowchart depicting a pages-per-sheet changing process in the first illustrative embodiment according to one or more aspects of the disclosure. 
           [0024]      FIG. 12  is a diagram illustrating a change of the number of pages per sheet in a second illustrative embodiment according to one or more aspects of the disclosure. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0025]    Illustrative embodiments are described in detail with reference to the accompanying drawings. 
         [0026]    Hereinafter, a first illustrative embodiment is described with reference to  FIGS. 1-11 . 
         [0027]    As depicted in  FIG. 1 , a personal computer (“PC”)  1 , which is an example of an information processing device, comprises a central processing unit (“CPU”)  10 , a read-only memory (“ROM”)  11 , a random-access memory (“RAM”)  12 , a display portion  13 , an operating portion  14 , a storage portion  15 , and a communication interface portion  16 . 
         [0028]    In one aspect, CPU  10  is configured to control functions of each portion of the PC  1  by executing programs stored in the ROM  11  or the storage portion  15 . In one aspect, ROM  11  is configured to store the programs to be executed by the CPU  10  and various data, the RAM  12  is configured to be used as a main storage when the CPU  10  performs various processing, the RAM  12  is an example of a memory and the CPU  10  is an example of a processor. 
         [0029]    In one aspect, the display portion  13  comprises a display unit and a display-unit driving circuit, the display unit comprises, for example, a liquid crystal display, and the display-unit driving circuit is configured to drive the display unit. 
         [0030]    The operating portion  14  comprises, for example, a keyboard, a mouse, and interfaces to which the keyboard and the mouse can be connected. 
         [0031]    The storage portion  15  comprises a nonvolatile memory, for example, a hard disk or a flash memory, and can be configured to store various programs and data therein. The storage portion  15  is configured to store an operating system (“OS”)  17 , an application program (hereinafter, simply referred to as “application”)  18 , and a printer driver program (hereinafter, simply referred to as “printer driver”)  19  for controlling functions of a printer  2 . The application  18  comprises any program that has a function of outputting data of a print target to the OS  17 , for example, a word processor or a spreadsheet program. The printer driver  19  is an example of a page-layout program. 
         [0032]    The communication interface portion  16  is configured to be connected to the printer  2  to allow the PC  1  to communicate with the printer  2  via a wired communication network, for example, a local-area network (“LAN”), a wireless communication network, a Universal Serial Bus (“USB”), or a parallel line. The communication interface portion  16  is further configured to send print data to the printer  2 . The print data is an example of output data. 
         [0033]    The printer  2  is configured to print an image represented by the print data received from the PC  1  onto a printing sheet. The printing sheet is an example of a sheet. In the first illustrative embodiment, the printer  2  is an electrophotographic printer that is configured to perform printing by using toner. Nevertheless, in other embodiments, for example, the printer  2  may be an inkjet printer configured to perform printing by using ink. The toner and the ink are an example of a colorant. 
         [0034]    As depicted in  FIG. 2 , a print screen  30  is displayed by the application  18 , and a print condition setting screen  35  is displayed by the printer driver  19 . A user can call up a printer driver for controlling a currently-selected printer by clicking a “properties” button  30   a  on the print screen  30 . In the first illustrative embodiment, it is assumed that the “properties” button  30   a  is clicked while the printer  2  is specified. 
         [0035]    In one aspect, the printer driver  19  called by the application  18  is configured to display the print condition setting screen  35  on the display portion  13  for allowing the user to specify one or more print conditions. The print condition setting screen  35  comprises various print setting items, for example, “number of copies”, “color/monochrome”, “double-sided printing/single-sided printing”, “pages per sheet”, “pages-per-sheet change setting” “pages-per-sheet changing method”, and “toner saving setting”. 
         [0036]    The number of pages per sheet is now described with reference to  FIG. 3 . The number of pages per sheet refers to the number of pages laid out on one side of a printing sheet. In the first illustrative embodiment, one of values 1, 2, 4, 9, and 16 is available to be specified as the number of pages per sheet. The user specifies a desired value from the values 1, 2, 4, 9, and 16 in the print setting item “pages per sheet”. A default value of the number of pages per sheet may be 1. Hereinafter, when the value 2 or greater is specified in the print setting item “pages per sheet”, N-in-1 printing is performed. 
         [0037]    As depicted in  FIG. 3 , when the value 2 is specified in the print setting item “pages per sheet”, pages to be printed are laid out on a landscape-oriented printing sheet. When one of the values 1, 4, 9, and 16 is specified in the print setting item “pages per sheet”, pages to be printed are laid out on a portrait-oriented printing sheet. 
         [0038]    In one aspect, a page may refer to data to be printed on one side of a printing sheet when the value “1” is specified in the print setting item “pages per sheet”. A plurality of pages outputted from the application  18  is an example of a page group 
         [0039]    With reference to  FIG. 2 , the print setting items are described in detail. The print setting item “pages-per-sheet change setting” specifies whether the number of pages per sheet is changed when the total number of pages included in a page group to be printed is changed by an instruction to delete one or more pages from a preview screen  40  (see  FIG. 4 ). The print setting item “pages-per-sheet change setting” is further descried below. The print setting item “pages-per-sheet change setting” comprises options of “To be changed” and “Not to be changed”, one of which may be selectively specified therein. 
         [0040]    The print setting item “pages-per-sheet changing method” specifies a method for changing the number of pages per sheet when the total number of pages included in the page group to be printed is changed in response to the instruction to delete one or more pages issued on the preview screen  40  (see  FIG. 4 ). The print setting item “pages-per-sheet changing method” is further described below. The print setting item “pages-per-sheet changing method” comprises options of a “first changing method” and a “second changing method”, one of which may be selectively specified therein. 
         [0041]    The print setting item “toner saving setting” specifies whether a toner consumption in printing of the pages included in the page group needs to be saved. The print setting item “toner saving setting” comprises options of “on” and “off”, one of which may be selectively specified therein. When the option “on” is specified in the print setting item “toner saving setting”, a size of each dot to be formed on a printing sheet is reduced in printing or the number of dots for each pixel of image data is reduced in printing. Therefore, the printing is performed with saving toner. 
         [0042]    When the user clicks one of an “OK” button  35   a  and a “cancel” button  35   b  on the print condition setting screen  35 , the print screen  30  appears. When the “OK” button  35   a  is clicked, the printer driver  19  is configured to display the print screen  30  after setting one or more newly-specified values, which have been changed from their default values by the user on the print condition setting screen  35 , to the corresponding print setting items, as print conditions. When the “cancel” button  35   b  is clicked, the printer driver  19  is configured to display the print screen  30  after setting the default values to the print setting items, as the print conditions. 
         [0043]    As the user clicks a “print” button  30   b  on the print screen  30 , print target data may be outputted by page from the application  18  to the printer driver  19  via the OS  17 . 
         [0044]    In the first illustrative embodiment, a page refers to data to be printed on one side of a printing sheet when the value “1” is specified in the print setting item “pages per sheet”. 
         [0045]    Processing for accepting a setting of the print conditions by displaying the print condition setting screen  35  is an example of pages-per-sheet setting processing, layout-method selecting processing, one-sided printing/double-sided printing selecting processing, economy setting processing. The processing in which the printer driver  19  receives a page group from the application  18  is an example of receiving processing. The single-sided printing is an example of a single-sided layout. The double-sided printing is an example of a double-sided layout. 
         [0046]    The preview screen  40  displayed by the printer driver  19  is now described with reference to  FIG. 4 . When the printer driver  19  receives the above-described page group from the application  18 , the printer driver  19  is configured to temporarily store the page group in the RAM  12  and then generate an image for preview on a page basis. Hereinafter, an image for preview is simply referred to as a preview image. 
         [0047]    After that, the printer driver  19  is configured to display a preview screen  40  on the display portion  13  with one or more preview images  41  displayed on the preview screen  40 . In  FIG. 4 , the preview images  41  are arranged in a row in order from left to right. The user scrolls the preview images  41  currently displayed on the preview screen  40  by using scroll arrows  40   a  and  40   b.    
         [0048]    The user checks the contents of the pages to be printed by viewing the preview images  41 . When the user finds one or more pages for which printing is not necessary, the user can delete the one or more unnecessary pages from the preview screen  40 . More specifically, the user can select one or more preview images  41  corresponding to one or more unnecessary pages and then click a “delete” button  40   c  to delete the one or more unnecessary pages corresponding to the one or more selected preview images  41 . Upon receipt of the page delete instruction, the printer driver  19  is configured to delete the one or more preview images  41  corresponding to the one or more unnecessary pages from the preview screen  40  and erase the data of the pages of the one or more deleted preview images  41  from the RAM  12 . 
         [0049]    That is, the user can change the total number of pages included in the page group to be printed by providing the page delete instruction through the preview screen  40  after specifying a desired value in the print setting item “pages per sheet” on the print condition setting screen  35 . 
         [0050]    The processing in which the printer driver  19  displays the preview screen  40  and erases one or more unnecessary pages corresponding to the selected preview images  41  from the RAM  12  is an example of total-page-number changing processing. 
         [0051]    When the total number of pages included in the page group to be printed is changed in response to the page delete instruction issued through the preview screen  40  while the N-in-1 printing has been specified, the printer driver  19  is configured to change the current value that has been specified in the print setting item “pages per sheet” by the user on the print condition setting screen  35  to another value. 
         [0052]    The method for changing the number of pages per sheet comprises a first changing method and a second changing method. The first and second changing methods are described below. Hereinafter, the value specified in the print setting item “pages per sheet” by the user on the print condition setting screen  35  is also referred to as an originally-specified value of the number of pages per sheet. 
         [0053]    With reference to  FIGS. 5 and 6 , the first changing method is now described. In the first changing method, the printer driver  19  is configured to change an originally-specified value of the number of pages per sheet to another value (e.g., a newly-specified value) that is smaller than the originally-specified value. Accordingly, in the print group in which pages have been deleted, the remaining pages are laid out by using the newly-specified value. This value may not exceed the number of printing sheets to be used when the pages included in the page group from which no page has been deleted are laid out by using the originally-specified value of the number of pages per sheet. 
         [0054]    Slightly different changing methods may be adopted for a case where the single-sided printing has been specified and a case where the double-sided printing has been specified, respectively. Therefore, the first changing method is described below with respect to each case. 
         [0055]    With reference to  FIG. 5 , the first changing method that is performed when the single-sided printing has been specified is described below. In  FIG. 5 , an outer rectangle may represent an image receiving side  45  of a printing sheet and an inner rectangle may represent a page  46 . The image receiving side  45  refers to a side on which one or more pages  46  is laid out for printing. In the single-sided printing, the number of image receiving sides  45  is equal to the number of printing sheets to be used. In the double-sided printing, each side of a printing sheet corresponds to the image receiving side  45 . 
         [0056]    When the single-sided printing has been specified, the printer driver  19  is configured to change the originally-specified value of the number of pages per sheet to one of the values N that may satisfy Expression 1 below and be smaller than the originally-specified value. 
         [0000]      The number of pages per sheet  N≧LPn/PPn 1  Expression 1:
 
         [0057]    In this embodiment, “LPn” represents the total number of pages included in the page group from which one or more pages  46  have been deleted. 
         [0058]    In this embodiment, “PPn1” represents the number of image receiving sides to be used when the pages included in the page group from which no page  46  has been deleted are laid out by using the originally-specified value of the number of pages per sheet. 
         [0059]    In this embodiment, “LPn/PPn1” represents the number of pages per image receiving side when the pages included in the page group from which one or more pages  46  have been deleted are laid out on the image receiving sides  45  that are equal in number to the number of image receiving sides to be used when the pages included in the page group from which no page  46  has been deleted are laid out by using the originally-specified value of the number of pages per sheet. 
         [0060]    In the example depicted in  FIG. 5 , it is assumed that a page group from which no page has been deleted includes six pages in total and an originally-specified value of the number of pages per sheet is “4”. In this case, the number of image receiving sides to be used when the pages included in the page group (e.g., six pages in total) are laid out by using the originally-specified value “4” of the number of pages per sheet “PPn1” is “2”. When two pages, e.g., pages 3 and 5, are deleted from the page group, the total number of pages remaining in the page group from which the one or more pages  46  (e.g., two pages) have been deleted “Lpn” is “4”. Therefore, in the example depicted in  FIG. 5 , the number of pages per sheet N is greater than or equal to 2 (N≧2 (=4/2)). 
         [0061]    When the originally-specified value of the number of pages per sheet was changed to another value that satisfies Expression 1, the number of image receiving sides to be used when the remaining pages included in the page group from which one or more pages  46  have been deleted are laid out by using the other value, i.e., a newly-specified value, may not exceed the number of image receiving sides to be used when the pages included in the page group from which no page  46  has been deleted are laid out by using the originally-specified value of the number of pages per sheet “PPn1”. 
         [0062]    In other words, the number of printing sheets to be used when the remaining pages included in the page group from which the one or more pages  46  has been deleted are laid out by using the newly-specified value of the number of pages per sheet does not exceed the number of printing sheets to be used when the pages included in the page group from which no page  46  has been deleted are laid out by using the originally-specified value of the number of pages per sheet. 
         [0063]    As described above, in the first illustrative embodiment, the value that is specified in the number of pages per sheet is limited to 1, 2, 4, 9 and 16. Therefore, the value of the number of pages per sheet that satisfies the number of pages per sheet N≧2 is one of the values 2, 4, 9 and 16. In this case, the originally-specified value of the number of pages per sheet is “4”. Therefore, a value that is specified and smaller than the originally-specified value “4” is “2”. Thus, the printer driver  19  changes the originally-specified value of the number of pages per sheet to “2”. 
         [0064]    In the example depicted in  FIG. 5 , the value that specifies the number of pages per sheet is limited to 1, 2, 4, 9 and 16. Therefore, the value of the number of pages per sheet that satisfies the number of pages per sheet N≧2 and smaller than the originally-specified value “4” is “2” only. Nevertheless, in other embodiments, for example, there are a plurality of available values that may be smaller than the originally-specified value “4”, for example, a value “3” may be specified in the number of pages per sheet, as a newly-specified value. The size of each page laid out on a printing sheet may become larger when a smaller value is specified in the number of pages per sheet. Thus, when there are a plurality of available values that may be smaller than the originally-specified value, the printer driver  19  changes the originally-specified value to the smallest value of the plurality of available values. 
         [0065]    In other cases, the value of the number of pages per sheet that satisfy Expression 1 is one of the values 4, 9, and 16. For example, in the example depicted in  FIG. 5 , when one page  46  is deleted from the page group, the total number of pages remaining in the page group “LPn1” is five pages, and the number of pages per sheet is N≧2.5(=5/2). Therefore, the value of the number of pages per sheet that satisfies the number of pages per sheet N≧2.5 is one of values 4, 9, and 16. In this case, the value that is smaller than the originally-specified value “4” is not present in the values N of the number of pages per sheet that satisfy Expression 1. Thus, the originally-specified value “4” is used without being changed. 
         [0066]    That is, in the first illustrative embodiment, the originally-specified value of the number of pages per sheet is changed only when one or more values that are smaller than the originally-specified value are present in the value N of the number of pages per sheet that satisfy Expression 1. The same condition may also be used in the other changing methods. 
         [0067]    With reference to  FIG. 6 , the first changing method that is performed when the double-sided printing has been specified is now described. In  FIG. 6 , only one page laid out on each image receiving side  45  of a printing sheet is assigned the reference numeral  46 . For the sake of brevity, the reference number  46  is omitted from the other pages. When the double-sided printing has been specified, the printer driver  19  determines the number of image receiving sides to be used “PPn1” on condition that one or more pages  46  are laid out on the other image-receiving side of the last printing sheet. 
         [0068]    More specifically, in an example depicted in  FIG. 6 , it is assumed that a page group from which no page has been deleted includes 12 pages in total and an originally-specified value of the number of pages per sheet is “4”. In this case, the number of image receiving sides to be used when the pages included in the page group (e.g., 12 pages in total) are laid out by using the originally-specified value “4” of the number of pages per sheet “PPn1” is “3”. When four pages, e.g., pages 9-12, are deleted from the page group, the total number of pages remaining in the page group from which the one or more pages  46  (e.g., four pages) have been deleted “Lpn” is “8”. 
         [0069]    In the example depicted in  FIG. 6 , the number of image receiving sides to be used “PPn1” is “3” which is an odd number. When the double-sided printing has been specified and the value of “PPn1” is an odd number, the printer driver  19  may add 1 to the value of “PPn1”. With this configuration, one or more pages are laid out on the other image-receiving side of the last printing sheet. 
         [0070]    In this case, when 1 is added to the value of “PPn1”, the value of “PPn1” becomes “4”. Therefore, in the example depicted in  FIG. 6 , the number of pages per sheet is N≧2 (=8/4). The value that satisfies the number of pages per sheet N≧2 is one of the values 2, 4, 9, and 16. In this case, the originally-specified value of the number of pages per sheet was “4”. Therefore, the value that is specified and that is smaller than the originally-specified value “4” is “2”. Thus, the printer driver  19  changes the originally-specified value of the number of pages per sheet to “2”. 
         [0071]    Next, with reference to  FIG. 7 , the second changing method is described. In the second changing method, the printer driver  19  is configured to change an originally-specified value of the number of pages per sheet to another value (e.g., a newly-specified value) that is smaller than the originally-specified value. Accordingly, in the print group in which pages have been deleted, the remaining pages are laid out by using the newly-specified value. This value does not exceed the number of printing sheets to be used when the pages remaining in the page group from which the one or more page have been deleted are laid out by using the originally-specified value of the number of pages per sheet. 
         [0072]    In the second changing method, also, slightly different changing methods are adopted for a case where the single-sided printing has been specified and a case where the double-sided printing has been specified, respectively. Therefore, the second changing method is described with respect to each case. 
         [0073]    With reference to  FIG. 7 , the second changing method that is performed when the single-sided printing has been specified is described below. When the single-sided printing has been specified, the printer driver  19  is configured to change the originally-specified value to the smallest value of N that satisfies Expression 2 below. 
         [0000]      The number of pages per sheet  N≧LPn/PPn 2  Expression 2:
 
         [0074]    In one aspect, “PPn2” represents the number of image receiving sides to be used when the pages remaining in the page group from which one or more pages  46  have been deleted are laid out by using the originally-specified value of the number of pages per sheet. 
         [0075]    In an example depicted in  FIG. 7 , it is assumed that a page group from which no page has been deleted includes thirty-five (35) pages in total, an originally-specified value of the number of pages per sheet is sixteen (16), and eighteen (18) pages, e.g., pages 16-33, are deleted from the page group. In this case, the total number of pages remaining in the page group from which the one or more pages  46  (e.g., 18 pages) have been deleted, “LPn”, is seventeen (17) pages, and the number of image receiving sides to be used when the pages (e.g., 17 pages in total) remaining in the page group from which the one or more pages  46  have been deleted are laid out by using the originally-specified value “16” of the number of pages per sheet, “PPn2”, is “2”. Therefore, the number of pages per sheet is N≧8.5 (=17/2). 
         [0076]    The value that satisfies the number of pages per sheet N≧8.5 is one of the values 9 and 16. In this case, the originally-specified value of the number of pages per sheet is “16”. Therefore, a value that is smaller than the originally-specified value is “9”. Thus, the printer driver  19  changes the originally-specified value of the number of pages per sheet to “9”. 
         [0077]    With reference to  FIG. 8 , the second changing method that is performed when the double-sided printing has been specified is now described. When the double-sided printing has been specified, the printer driver  19  determines the number of image receiving sides to be used, “PPn2”, on condition that one or more pages  46  are laid on the other imagereceiving side of the last printing sheet. 
         [0078]    More specifically, in an example depicted in  FIG. 8 , it is assumed that a page group from which no page has been deleted includes 11 pages in total, an originally-specified value of the number of pages per sheet is “4”, and eight pages, e.g., pages 4-11, are deleted from the page group. In this case, the total number of pages remaining in the page group from which the one or more pages  46  (e.g., eight pages) have been deleted, “LPn”, is “3”, and the number of image receiving sides to be used when the pages (e.g., three pages in total) remaining in the page group from which the one or more pages  46  have been deleted are laid out by using the originally-specified value “4” of the number of pages per sheet, “PPn2”, is “1”. 
         [0079]    In the example depicted in  FIG. 8 , the number of image receiving sides to be used, “PPn2”, is “1” which is an odd number. When the value of “PPn2” is an odd number, the printer driver  19  adds 1 to the value of “PPn2”. In this case, when 1 is added to the value of “PPn2”, the value of “PPn2” becomes “2”. Therefore, in the example depicted in  FIG. 8 , the number of pages per sheet is N≧1.5 (=3/2). The value that satisfies the number of pages per sheet N≧1.5 is one of the values 2, 4, 9, and 16. In this case, the originally-specified value of the number of pages per sheet is “4”. Therefore, the value that is smaller than the originally-specified value “4” is “2”. Thus, the printer driver  19  changes the originally-specified value of the number of pages per sheet to “2”. 
         [0080]    As described above, when one or more pages are deleted from a page group, the printer driver  19  changes the originally-specified value of the number of pages per sheet to another value that is smaller than the originally-specified value. Nevertheless, there may be some exceptions as described below. Hereinafter, examples are described as to cases where the number of pages per sheet is not changed although one or more pages are deleted from a page group. 
         [0081]    With reference to  FIG. 9 , one example of the exceptions is described. In this example, it is assumed that a page group from which no page has been deleted includes 4 pages in total, an originally-specified value of the number of pages per sheet is “4”, and two pages are deleted from the page group. When the originally-specified value of the number of pages per sheet is changed in accordance with the first changing method, the number of pages per sheet is N≧2 (=2/1). Therefore, the newly-specified value of the number of pages per sheet is “2”. 
         [0082]    As described above, the printer driver  19  is configured to lay out the pages on one or more landscape-oriented printing sheets when the value “2” is specified in the number of pages per sheet. It is assumed that a height of a landscape-oriented sheet is half of a height of a portrait-oriented printing sheet. In this case, when the originally-specified value of the number of pages per sheet is changed from “4” to “2”, a height of each page laid out by using the originally-specified value (i.e., the value “4”) “LS1” is substantially half of the height of the portrait-oriented printing sheet. However, a height of each page laid out by using the newly-specified value (i.e., the value “2”) “LS2” is shorter than a half of the height of the portrait-oriented printing sheet. That is, the size of each page laid out by using the newly-specified value of the number of pages per sheet becomes smaller than the size of each page laid out by using the originally-specified value of the number of pages per sheet. 
         [0083]    In some cases, depending on upper, lower, right, and left margins, a height of an area in the landscape-oriented printing sheet from which the upper, lower, right, and left margins are omitted is less than a half of a height of an area in the portrait-oriented printing sheet from which the upper, lower, right, and left margins are omitted. In this case, also, when the originally-specified value of the number of pages per sheet is changed from “4” to “2”, the size of each page laid out by using the newly-specified value of the number of pages per sheet becomes smaller than the size of each page laid out by using the originally-specified value of the number of pages per sheet. 
         [0084]    The size reduction of each page makes it difficult for the user to confirm the contents of each page. Therefore, when the size of each page laid out by using the newly-specified value of the number of pages per sheet becomes smaller than the size of each page laid out by using the originally-specified value of the number of pages per sheet, the printer driver  19  is configured not to change the originally-specified value of the number of pages per sheet although one or more pages  46  are deleted from the page group. 
         [0085]    When pages are laid out by using the newly-specified value of the number of pages per sheet, an amount of toner to be used for printing is increased as compared with the amount of toner to be used for printing when the pages are laid out by using the originally-specified value of the number of pages per sheet. For example, in the example depicted in  FIG. 5 , when the pages are laid out by using the newly-specified value of the number of pages per sheet, the amount of toner to be used for printing is increased because a printing area of each page is expanded. 
         [0086]    When the option “on” is specified in the print setting item “toner saving setting”, increasing the amount of toner to be used for printing is undesirable. Therefore, when the option “on” has been specified in the print setting item “toner saving setting”, the printer driver  19  is configured not to change the originally-specified value of the number of pages per sheet to another value although one or more pages are deleted from the page group. 
         [0087]    As described above, one of the options of “To be changed” and “Not to be changed” is specified in the print setting item “pages-per-sheet change setting” on the print condition setting screen  35 . When the option “Not to be changed” is specified in the print setting item “pages-per-sheet change setting”, the printer driver  19  is configured not to change the originally-specified value of the number of pages per sheet although one or more pages are deleted from the page group. 
         [0088]    A printing process is now described with reference to  FIG. 10 . The printing process starts as the application  18  outputs a page group to the printer driver  19 . 
         [0089]    At step S 101 , the CPU  10  that runs the printer driver  19  (hereinafter, simply referred to as the printer driver  19 ) stores the page group received from the application  18  in the RAM  12 . 
         [0090]    At step S  102 , the printer driver  19  generates print data for printing pages included in the page group stored in the RAM  12  on one or more printing sheets while the pages are laid out on each of the one or more printing sheets in accordance with an originally-specified value specified in the print setting item “pages per sheet” on the print condition setting screen  35 . 
         [0091]    A data format of the print data is, for example, Enhanced Metafile format (“EMF”) or a format described in a page description language specific to the printer  2 . 
         [0092]    In the first illustrative embodiment, the data format of the print data is EMF. The print data in EMF comprises data representing each page, and layout information defining a location of each page to be laid out on a printing sheet. The print data in EMF permits its contents to be formatted later. 
         [0093]    In this embodiment, the printer driver  19  is configured to generate image data representing a printing sheet, wherein the pages included in the page group are laid out on an imaginary printing sheet stored in the RAM  12  and handle the generated image data as print data. In other cases, the printer driver  19  is configured to perform a color space conversion or a binarization on the generated image data to obtain halftone image data and to handle the halftone image data as print data. 
         [0094]    At step S  103 , the printer driver  19  is configured to generate preview images  41  for the respective pages stored in the RAM  12  and display a preview screen  40  on the display portion  13  while displaying the preview images  41  on the preview screen  40 . 
         [0095]    As described above, the user selects a preview image  41  representing an unnecessary page from the generated preview images  41  and provides an instruction to delete the selected preview image  41  on the preview screen  40 . As the printer driver  19  receives the page delete instruction, the printer driver  19  deletes a page corresponding to the selected preview image  41 . At this point, the user is allowed to select a plurality of preview images  41  and provide an instruction to delete the plurality of selected preview images  41 . When the printer driver  19  receives the page delete instruction to delete the plurality of preview images  41 , the printer driver  19  deletes a plurality of pages corresponding to the selected preview images  41  at once. 
         [0096]    At step S 104 , the printer driver  19  determines whether at least one of the pages in the page group has been deleted at step S  103 . When at least one of the pages in the page group has been deleted (YES at step S 104 ), the routine moves to step S 105 . When none of the pages included in the page group has been deleted (NO at step S  104 ), the routine moves to step S  112 . The processing of step S 104  is an example of determining processing. 
         [0097]    At step S  105 , the printer driver  19  determines whether N-in-1 printing has been specified. When the N-in-1 printing has been specified (YES at step S 105 ), the routine moves to step S 106 . When the N-in-1 printing has not been specified (NO at step S 105 ), the routine moves to step S 111 . 
         [0098]    At step S  106 , the printer driver  19  determines whether the option “To be changed” has been specified in the print setting item “pages-per-sheet change setting”. When the option “To be changed” has been specified (YES at step S 106 ), the routine moves to step S 107 . When the option “Not to be changed” has been specified (NO at step S 106 ), the routine moves to step S 111 . 
         [0099]    At step S  107 , the printer driver  19  determines whether the option “on” has been specified in the print setting item “toner saving setting”. When the option “off” has been specified” (NO at step S  107 ), the routine moves to step S  108 . When the option “on” has been specified (YES at step S  107 ), the routine moves to step S 111 . 
         [0100]    At step S  108 , the printer driver  19  performs the pages-per-sheet changing process. In the pages-per-sheet changing process, the originally-specified value specified in the print setting item “pages per sheet” is changed by using one of the first changing method and the second changing method. The pages-per-sheet changing process is further described below. 
         [0101]    At step S  109 , the printer driver  19  determines whether the originally-specified value specified in the print setting item “pages per sheet” has been changed to another value at step S  108 . As a result of the determination of step S  108 , when the currently-specified value is the same as the originally-specified value specified by the user on the print condition setting screen  35 , the printer driver  19  determines that the originally-specified value has not been changed. When the originally-specified value has been changed to another value (YES at step S 109 ), the routine moves to step S 110 . When the originally-specified value has not been changed to another value (NO at step S 110 ), the routine moves to step S 111 . 
         [0102]    At step S 110 , the printer driver  19  formats the print data generated at step S 102  such that the print data is to be printed on one or more printing sheets and the pages remaining in the page group from which the one or more pages have been deleted are laid out on each printing sheet by using the newly-specified value specified in the print setting item “pages per sheet”. 
         [0103]    At step S 111 , the printer driver  19  formats the print data generated at step S 102  such that the print data is to be printed on one or more printing sheets and the pages remaining in the pages group are laid out on each printing sheet by using the originally-specified value specified in the print setting item “pages per sheet” by the user on the print condition setting screen  35 . 
         [0104]    At step S  112 , the printer driver  19  transmits the print data to the printer  2  after converting the print data into a format interpretable by the printer  2 . 
         [0105]    The processing of steps S 102 , S 110 , and S 111  is an example of generating processing. 
         [0106]    With reference to  FIG. 11 , the pages-per-sheet changing process of step S 108  is now described. 
         [0107]    At step S 201 , the printer driver  19  obtains the page height “LS1” of each page that is included in the page group from which no page has been deleted and laid out on one or more printing sheets by using the originally-specified value (see  FIG. 9 ). 
         [0108]    At step S 202 , the printer driver  19  determines which one of the first changing method and the second changing method has been specified. When the first changing method has been specified, the routine moves to step S 203 . When the second changing method has been specified, the routine moves to step S 210 . 
         [0109]    The processing of steps S 203 -S 209  is performed when the first changing method has been specified. 
         [0110]    At step S 203 , the printer driver  19  determines which one of the double-sided printing and the single-sided printing has been specified. When the double-sided printing has been specified, the routine moves to step S 204 . When the single-sided printing has been specified, the routine moves to step S 206 . 
         [0111]    At step S 204 , the printer driver  19  determines whether the value of “PPn1” (i.e., the number of image receiving sides to be used when the pages included in the page group from which no page has been deleted are laid out by using the originally-specified value of the number of pages per sheet) is an odd number. When the value of “PPn1” is an odd number (YES at step S 204 ), the routine moves to step S 205 . When the value of “PPn1” is an even number (NO at step S 204 ), the routine moves to step S 206 . 
         [0112]    At step S 205 , the printer driver  19  adds 1 to the value of “PPn1”. 
         [0113]    At step S 206 , the printer driver  19  determines the smallest value of the number of pages per sheet that satisfies Expression 1. 
         [0114]    At step S 207 , the printer driver  19  obtains the page height “LS2” of each page that remains in the page group from which the one or more pages have been deleted and is laid out on one or more printing sheets by using the value of the number of pages per sheet specified at step S 206  (see  FIG. 9 ). 
         [0115]    At step S 208 , the printer driver  19  determines whether a relationship between the page height “LS1” and the page height “LS2” satisfies a relationship of LS1&lt;LS2. When the relationship between the page height “LS1” and the page height “LS2” satisfies the relationship of LS1&lt;LS2 (YES at step S 108 ), the routine may move to step S 209 . When the relationship between the page height “LS1” and the page height “LS2” does not satisfy the relationship of LS1&lt;LS2 (i.e., LS1≧LS2) (NO at step S  108 ), the pages-per-sheet changing process is ended and the routine moves back to the printing process. 
         [0116]    At step S 209 , the printer driver  19  changes the value of the number of pages per sheet from the originally-specified value to the value specified at step S 206 . Here, when the value specified at step S 206  is different from the originally-specified value specified by the user on the print condition setting screen  35 , the printer driver  19  changes the value of the number of pages per sheet from the originally-specified value to the value specified at step S 206 . 
         [0117]    processing of steps S 210 -S 216  is performed when the second changing method has been specified. 
         [0118]    At step S 210 , the printer driver  19  determines which one of the double-sided printing and the single-sided printing has been specified. When the double-sided printing has been specified, the routine moves to step S 211 . When the single-sided printing has been specified, the routine moves to step S 213 . 
         [0119]    At step S 211 , the printer driver  19  determines whether the value of “PPn2” (i.e., the number of image receiving sides to be used when the pages remaining in the page group from which the one or more pages have been deleted are laid out by using the originally-specified value of the number of pages per sheet) is an odd number. When the value of “PPn2” is an odd number (YES at step S 211 ), the routine moves to step S 212 . When the value of “PPn2” is an even number (NO at step S 211 ), the routine moves to step S 213 . 
         [0120]    At step S 212 , the printer driver  19  adds 1 to the value of “PPn2”. 
         [0121]    At step S 213 , the printer driver  19  determines the smallest value of the number of pages per sheet that satisfies Expression 2. 
         [0122]    At step S 214 , the printer driver  19  obtains the page height “LS2” of each page that remains in the page group from which the one or more pages have been deleted and is laid out on one or more printing sheets by using the value of the number of pages per sheet specified at step S 213  (see  FIG. 9 ). 
         [0123]    At step S 215 , the printer driver  19  determines whether a relationship between the page height “LS1” and the page height “LS2” satisfies a relationship of LS1&lt;LS2. When the relationship between the page height “LS1” and the page height “LS2” satisfies the relationship of LS1&lt;LS2 (YES at step S 215 ), the routine moves to step S 216 . When the relationship between the page height “LS1” and the page height “LS2” does not satisfy the relationship of LS1&lt;LS2 (i.e., LS1≧LS2) (NO at step S 215 ), the pages-per-sheet changing process is ended and the routine moves back to the printing process. 
         [0124]    At step S 216 , the printer driver  19  changes the value of the number of pages per sheet from the originally-specified value to the value specified  5213 . Here, when the value specified at step S 213  is different from the originally-specified value specified by the user on the print condition setting screen  35 , the printer driver  19  changes the value of the number of pages per sheet from the originally-specified value to the value specified at step S 213 . 
         [0125]    According to the first illustrative embodiment, when the total number of pages in the page group is changed after the value of the number of pages per sheet was specified on the print condition setting screen  35 , the printer driver  19  is configured to change the originally-specified value of the number of pages per sheet to another value. 
         [0126]    For example, in the prior art, when the originally-specified value of the number of pages per sheet was not changed although the total number of pages in the page group was changed after the value of the number of pages per sheet had been specified by the user, wasted space may appear on a printing sheet when the pages are printed on one or more printing sheets. By contrast, according to the first illustrative embodiment, the printer driver  19  is configured to change the originally-specified value of the number of pages per sheet to another value when the total number of pages in the page group is changed after the value of the number of pages per sheet was specified by the user on the print condition setting screen  35 . Therefore, printing is performed by fully using space of one or more printing sheets. 
         [0127]    Further, when one or more pages are deleted from the page group after the value of the number of pages per sheet was specified by the user, the printer driver  19  is configured to change the originally-specified value of the number of pages per sheet to a smaller value. When the originally-specified value of the number of pages per sheet is changed to a smaller value, the size of each page included in the page group to be printed becomes larger on the preview screen  40 . Therefore, the user may confirm the contents of the pages more easily. Thus, user&#39;s usability is improved. 
         [0128]    Further, according to the first illustrative embodiment, when the size of each page that remains in the page group from which one or more pages have been deleted and is laid out on one or more printing sheets by using the newly-specified value of the number of pages becomes smaller than the size of each page that is included in the page group from which no page has been deleted and laid out on one or more printing sheets by using the originally-specified value, the printer driver  19  is configured not to change the originally-specified value of the number of pages per sheet although one or more pages are deleted from the page group. This configuration allows the user to confirm the contents of the pages without difficulty. 
         [0129]    Further, according to the first illustrative embodiment, in the first changing method, the printer driver  19  is configured to change the originally-specified value of the number of pages per sheet to another value that is smaller than the originally-specified value such that the number of printing sheets to be used when pages remaining in a page group from which one or more pages have been deleted are laid out by using the other value (i.e., the newly-specified value) of the number of pages per sheet does not exceed the number of printing sheets to be used when the pages included in the page group from which no page has been deleted are laid out by using the originally-specified value of the number of pages per sheet. Therefore, printing is performed on the number of printing sheets allowed by the user, fully using the space of the printing sheets. 
         [0130]    For example, in the example depicted in  FIG. 5 , the user specifies, on the print condition setting screen  35 , that the pages (e.g., six pages in total) of the page group from which no page has been deleted are laid out on one or more printing sheets by using the originally-specified value “4” of the number of pages per sheet. Therefore, the pages are printed on two printing sheets. If the value of the number of pages per sheet remains “4” after two pages are deleted, only one printing sheet may be needed for printing the remaining pages. However, even when two printing sheets are used for the printing of the remaining pages, the number of printing sheets to be used does not exceed the number of printing sheets to be used specified by the user on the print condition setting screen  35 . Therefore, after one or more pages are deleted, the originally-specified value of the number of pages per sheet is changed to another value, e.g., “2”. By doing so, the size of each page remaining in the page group is increased by using two printing sheets. Thus, printing may be performed on the number of printing sheets allowed by the user, fully using the space of the printing sheets. The example depicted in  FIG. 6  also provides the same effect. 
         [0131]    Further, according to the first illustrative embodiment, in the second changing method, the printer driver  19  is configured to change an originally-specified value of the number of pages per sheet to another value that may be smaller than the originally-specified value such that the number of printing sheets to be used when pages remaining in a page group from which one or more pages have been deleted are laid out by using the other value (i.e., a newly-specified value) of the number of pages per sheet does not exceed the number of printing sheets to be used when the pages remaining in the page group from which the one or more page have been deleted are laid out by using the originally-specified value of the number of pages per sheet. Thus, printing may be performed on the number of printing sheets allowed by the user, fully using the space of the printing sheets. 
         [0132]    In the example depicted in  FIG. 7 , it is assumed that the number of printing sheets to be used that is allowed by the user is “2” which is the number of printing sheets to be used when the pages remaining in the page group (e.g., 17 pages in total) from which one or more pages have been deleted are laid out by using the originally-specified value “16” of the number of pages per sheet. In the example depicted in  FIG. 7 , if the value of the number of pages per sheet remains “16” after one or more pages are deleted from the page group, two printing sheets are still needed for printing the pages remaining in the page group. However, in this case, only one page is laid out on one side of a second printing sheet. Therefore, wasted space may appear on the second printing sheet. Nevertheless, when the originally-specified value of the number of pages per sheet is changed to a smaller value, e.g., the value “9”, the second printing sheet may be further effectively used. That is, the size of each page may be increased, and thus, printing may be performed on the number of printing sheets allowed by the user, fully using the space of the printing sheets. The example depicted in  FIG. 8  also provides the same effect. 
         [0133]    According to the first illustrative embodiment, the printer driver  19  is configured to allow the user to select one of the first changing method and the second changing method for changing the number of pages per sheet. Therefore, this configuration provides the user with flexibility. 
         [0134]    According to the first illustrative embodiment, when the double-sided printing has been specified, the printer driver  19  is configured to change the originally-specified value of the number of pages per sheet to another value on condition that one or more pages are laid out on the other image-receiving side of the last printing sheet. Therefore, the other image-receiving side of the last printing sheet may be effectively used. 
         [0135]    According to the first illustrative embodiment, when the option “on” has been specified in the print setting item “toner saving setting”, the printer driver  19  is configured not to change the originally-specified value of the number of pages per sheet to another value although one or more pages are deleted from the page group. Therefore, the amount of toner to be used in printing is not increased as compared with an amount of toner to be used when pages are laid out by using the originally-specified value of the number of pages per sheet. 
         [0136]    According to the first illustrative embodiment, the printer driver  19  is configured to display the preview images  41  and delete one or more pages that are required to be deleted by using one or more preview images  41  corresponding to the one or more unnecessary pages. Therefore, the printer driver  19  is configured to change the total number of pages included in the page group by itself. That is, the total number of pages included in the page group is changed without an external program for changing the total number of pages in the page group. 
         [0137]    Next, a second illustrative embodiment is described with reference to  FIG. 12 . 
         [0138]    In the first illustrative embodiment, when one or more pages are deleted after the value of the number of pages per sheet was specified on the print condition setting screen  35 , another value that is smaller than the originally-specified value may be specified as the newly-specified value of the number of pages per sheet. Nevertheless, according to the second illustrative embodiment, for example, when one or more pages are added to the page group after the value of the number of pages per sheet was specified on the print condition setting screen  35 , another value that is greater than the originally-specified value may be specified as the newly-specified value of the number of pages per sheet. 
         [0139]    The changing of the originally-specified value of the number of pages per sheet according to the second illustrative embodiment is now described. For example, it is assumed that Chapter 1 includes pages 1-3, Chapter 2 includes page 4, and the user requires that Chapter 1 and Chapter 2 be printed on separated sheets. 
         [0140]    In the second illustrative embodiment, a blank page is added on the preview screen  40 . For example, it is assumed that the user inserted a blank page between page 3 and page 4. 
         [0141]    In response to this, the printer driver  19  changes the originally-specified value of the number of pages per sheet to another value that is greater than the originally-specified value of the number of pages per sheet such that the number of printing sheets to be used when pages included in the page group to which one or more pages have been added are laid out by using the other value (i.e., a newly-specified value) of the number of pages per sheet is not less than the number of printing sheets to be used when the pages included in the page group to which no page has been added are laid out by using the originally-specified value of the number of pages per sheet. 
         [0142]    In the example depicted in  FIG. 12 , the originally-specified value of the number of pages per sheet is changed to a greater value, e.g., to “4”, from “2”. When the pages (e.g., five pages in total) included in the page group to which one or more pages have been added are laid out by using the newly-specified value “4” of the number of pages per sheet, the number of printing sheets to be used is “2”. Therefore, the number of pages per sheet may be increased such that the number of printing sheets to be used when the pages included in the page group to which the one or more pages have been added are laid out by using the newly-specified value of the number of pages per sheet may not become less than “2” which is the number of printing sheets to be used when the pages included in the page group (e.g., four pages in total) to which no page has been added are laid out by using the originally-specified value, e.g., “2”, of the number of pages per sheet. 
         [0143]    According to the second illustrative embodiment, the printer driver  19  is configured to change the originally-specified value of the number of pages per sheet to a value that is greater than the originally-specified value. 
         [0144]    If the originally-specified value of the number of pages per sheet was not changed although the total number of pages in the page group was changed due to the addition of one or more pages after the number of pages per sheet had been changed, the number of printing sheets to be used is increased. According to the second illustrative embodiment, the printer driver  19  is configured to change the originally-specified value of the number of pages per sheet when the total number of pages in the page group was changed after the value of the number of pages per sheet had been specified by the user on the print condition setting screen  35 . Therefore, this configuration prevents the increase of the number of printing sheets to be used although one or more pages are added to the page group after the value of the number of pages per sheet was specified by the user on the print condition setting screen  35 . 
         [0145]    Further, according to the second illustrative embodiment, the printer driver  19  is configured to change the originally-specified value of the number of pages per sheet to another value that is greater than the originally-specified value of the number of pages per sheet such that the number of printing sheets to be used when pages included in the page group to which one or more pages have been added are laid out by using the other value (i.e., a newly-specified value) of the number of pages per sheet is not less than the number of printing sheets to be used when the pages included in the page group to which no page has been added are laid out by using the originally-specified value of the number of pages per sheet. Therefore, printing may be performed on the number of printing sheets allowed by the user, fully using the space of the printing sheets. 
         [0146]    In other embodiments, for example, the originally-specified value of number of pages per sheet may be changed to another value that may be greater than the originally-specified value such that the number of printing sheets to be used when pages included in the page group to which one or more pages have been added are laid out by using the other value (i.e., a newly-specified value) of the number of pages per sheet may not become less than the number of printing sheets to be used when the pages included in the page group to which one or more pages have been added are laid out by using the originally-specified value of the number of pages per sheet. 
         [0147]    The aspects of the disclosure may not be limited to the specific illustrative embodiments described with reference to the above description and the accompanying drawings. For example, other embodiments described below may also be included within the technical scope of the disclosure. 
         [0148]    In the above-described illustrative embodiments, the description has been made by using a physical printing sheet as an example of the sheet. Nevertheless, in other embodiments, for example, the sheet may be a logical printing sheet. For example, the sheet may be a virtual printing sheet to be displayed on a screen. 
         [0149]    In the above-described illustrative embodiments, the description has been made by using print data as an example of output data. Nevertheless, in other embodiments, for example, the output data may be text data in Portable Document Format (“PDF”). When the text data is displayed on the display portion  13  after the originally-specified value of the number of pages per sheet was changed, pages included in a page group in which the total number of pages has been changed are laid out on one or more virtual printing sheets by using the newly-specified value of the number of pages per sheet. 
         [0150]    In the above-described illustrative embodiments, the user may be allowed to select one of the first changing method and the second changing method. Nevertheless, in other embodiments, for example, the changing method of the number of pages per sheet may be fixed to one of the first changing method and the second changing method. 
         [0151]    In the above-described illustrative embodiments, the user may be allowed to specify one of the options of “To be changed” and “Not to be changed” in the print setting item “pages-per-sheet change setting”. Nevertheless, in other embodiments, for example, the user may not be allowed to specify any option in the print setting item “pages-per-sheet change setting” and the originally-specified value of the number of pages per sheet may always be changed when one or more pages are deleted from the page group. 
         [0152]    In the above-described illustrative embodiments, the originally-specified value of the number of pages per sheet may not be changed when the option “off” is specified in the print setting item “toner saving setting”. Nevertheless, in other embodiments, for example, the originally-specified value of the number of pages per sheet may be changed regardless of the setting value of the print setting item “toner saving setting” when one or more pages are deleted from the page group. 
         [0153]    In the above-described illustrative embodiments, the pages-per-sheet changing method may be different for the double-sided printing and for the single-sided printing. Nevertheless, in other embodiments, for example, the originally-specified value of the number of pages per sheet may be changed by using the changing method for the single-sided printing at all times without depending on the setting value of the print setting item “double-sided printing/single-sided printing”. 
         [0154]    In the above-described illustrative embodiments, it may be determined whether the size of each page to be laid out by using the newly-specified value of the number of pages per sheet becomes smaller than the size of each page to be laid out by using the originally-specified value of the number of pages per sheet. When the size of each page to be laid out by using the newly-specified value of the number of pages per sheet becomes smaller, the originally-specified value of the number of pages per sheet may not be changed although one or more pages are deleted from the page group. Nevertheless, in other embodiments, for example, the originally-specified value of the number of pages per sheet may be changed without performing the above determination when one or more pages are deleted from the page group. 
         [0155]    In the above-described illustrative embodiments, the printer driver  19  may be configured to display the preview screen  40 . Nevertheless, in other embodiments, for example, the printer driver  19  may be configured to call an external program for displaying the preview screen  40  to display the preview screen  40 . 
         [0156]    In the above-described illustrative embodiments, the total number of pages in the page group may be changed by the user&#39;s instruction to delete one or more pages issued on the preview screen  40 . Nevertheless, in other embodiments, for example, the total number of pages in the page group may be changed without using the preview screen  40 . 
         [0157]    In other embodiments, for example, when a blank page is included in the page group, the printer driver  19  may be configured to automatically delete the blank page to change the total number of pages in the page group. 
         [0158]    In the above-described illustrative embodiments, the printer driver  19  may be configured to transmit data outputted by the application  17  to the printer  2 . Nevertheless, in other embodiments, for example, a scanner may be adopted instead of the printer  2 . That is, a scanner driver installed on the PC  1  may be configured to obtain data read by the scanner and lay out pages included in the data on a plurality of printing sheets. 
         [0159]    In the above-described illustrative embodiments, the processing performed by the printer driver  19  may be also executed by printers, copying machines, facsimile machines, scanners, or appropriate devices. That is, the one or more aspects of the disclosure may be applied to a case where data received from an external device or data read by the device itself may be laid out on one or more printing sheets.