Patent Publication Number: US-6665086-B2

Title: Automatic and transparent archiving of documents and document information

Description:
STATEMENT OF RELATED APPLICATIONS 
     The present application is a continuation of and claims priority from U.S. patent application Ser. No. 08/754,721 filed Nov. 21, 1996 (which issued as U.S. Pat. No. 5,978,477), the entire contents of which are herein incorporated by reference for all purposes. 
     The present application is related to the subject matter of the application titled, “DOCUMENT MANAGEMENT SYSTEM” co-assigned with the present application and filed on the same day. The contents of the “DOCUMENT MANAGEMENT SYSTEM” application are herein incorporated by reference for all purposes. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to a document management system and more particularly to providing automatic archiving to standard office equipment. 
     With the rapid development of storage system technology, the cost of storing an image of a sheet of paper on digital media has become less than the cost of printing and storing the sheet of paper itself. Digital document storage also facilitates later electronic search and retrieval and raises the possibility of automatic filing of documents. 
     Until now, systematic digital document storage has required user discipline to scan in each and every document for the express purpose of archiving. Work has been done to make stand-alone scanners less expensive, easier to use, and more compact. However, the user must still 1) remember that a document should be scanned, 2) locate a scanner, 3) bring the document to the scanner, and 4) operate the scanner. However, scanning occurs constantly in the office environment in the contexts of copying and faxing. 
     SUMMARY OF THE INVENTION 
     The present invention provides an automatic archiving system that makes document archiving largely transparent to the user. In one embodiment, documents scanned in or printed during the course of office equipment operation are automatically archived. For example, an office local area network (LAN) may interconnect a copier, a printer, a facsimile machine, and a document management workstation. Whenever, a document is copied, printed, or faxed, a document image is archived by the document management workstation without further user intervention. A single user command results in the document being copied and archived, printed and archived, or faxed and archived. 
     In accordance with a first aspect of the invention, a method for processing document images includes steps of receiving a single user input command and performing certain steps in response to the single user input command. The steps include scanning a document image to collect image data, printing the document image based on the image data, and sending the image data to an archiving system for storage. 
     In accordance with a second aspect of the invention, a method for printing and archiving documents includes steps of receiving a single user command requesting that a document be printed, printing the document in response to the single user command, and archiving image data representing the document in response to the single user command. 
     In accordance with a third aspect of the invention, a method for archiving documents to be faxed includes steps of receiving a single user command indicating that a document is to be faxed, scanning the document to be faxed in response to the single user command, transmitting first image data representing the document as scanned to a remote location via a public telephone network, and archiving, in response to the single user command, second image data representing the document as scanned in the scanning step. 
     In accordance with a fourth aspect of the invention, a computer installation includes a digital copier that scans in documents to be copied, a printer that prints documents, a computer system controlling a long-term storage medium, and a network interconnecting the digital copier, the printer, and the computer system. The digital copier relays image data representing the documents to be copied to the computer system for storage on the long-term storage medium. The printer, or a printer server controlling the printer, or a computer system initiating a command to print relays image data representing printed documents to the computer system for storage on the long-term storage medium. 
     In accordance with a fifth aspect of the invention, a digital copier includes a scanner that generates image data representing a document to be copied, an image processing unit that processes the image data to correct imaging errors introduced by the scan engine, a printer that copies the document responsive to the image data as processed by the image processing unit, and an image data tap that relays the image data to a storage system for archiving. 
     A further understanding of the nature and advantages of the inventions herein may be realized by reference to the remaining portions of the specification and the attached drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 depicts an office machine network implementing automatic document archiving in accordance with one embodiment of the present invention. 
     FIG. 2 depicts a portion of a copier control interface. 
     FIG. 3 depicts a top-level diagram of a digital copier implementing automatic document archiving in accordance with one embodiment of the present invention. 
     FIG. 4 depicts alternative signals usable for extracting horizontal synchronization data from a digital copier in accordance with one embodiment of the present invention. 
     FIG. 5 depicts a printer interface. 
     FIG. 6 depicts a facsimile machine interface. 
     FIG. 7 depicts a facsimile machine modified for automatic archiving in accordance with one embodiment of the present invention. 
     FIG. 8 depicts a computer system usable for implementing elements of the present invention. 
     FIG. 9 depicts a software architecture for operating a document image database in accordance with one embodiment of the present invention. 
    
    
     DESCRIPTION OF SPECIFIC EMBODIMENTS 
     Overall Architecture for Automatic Archiving 
     FIG. 1 depicts an office machine network implementing automatic document archiving in accordance with one embodiment of the present invention. A network  100  may be implemented in any way, e.g., an Ethernet. Network  100  interconnects a representative client system  102 , a print server  104 , a special digital copier  106 , a document management workstation  108 , and a special facsimile machine  110 . Print server  104  controls printing on a representative printer  112  at the request of client system  102  and relays document image data characterizing a document to document management workstation  108  for archiving. Digital copier  106  copies documents and transmits image data obtained during the course of copying to document management workstation  108  for archiving. Similarly, facsimile machine  110  captures image data during the course of sending and receiving documents and transmits the image data to document management workstation  108  for archiving. Document management workstation  108  collects the document image data collected from all of the office equipment and maintains an archive on a disk storage unit  114 . Client system  102  may browse this archive. 
     The configuration of network  100  is of course only representative. For example, automatic archiving of documents may be implemented with only one or two types of office machine instead of the depicted types. Also, functionality of one or more units shown in FIG. 1 may be combined into the same unit or divided among many units. 
     Automatic Archiving of Copied Documents 
     In accordance with the present invention, digital copier  106  transparently archives documents that are copied. FIG. 2 depicts a simplified representation of a portion of a copier control interface  200  usable with digital copier  106 . Copier control interface  200  includes a numeric keypad  202 , an Enter key  204 , and a Copy/Start key  206 . Copier control interface  200  may be implemented using, e.g., a touch pad, touch screen, mechanical buttons, etc. Controls for paper size, copy darkness, copy contrast, paper size, and magnification/reduction ratio are not important to the present invention and are thus omitted. 
     In accordance with one embodiment of the present invention, activation of Copy/Start key  206  is sufficient to initiate both copying of a document and archiving of an image of the document. The user positions the document, e.g., in a document feeder (not shown), and then enters a personal access code on numeric keypad  202  finishing access code entry by depressing Enter key  204 . Depressing Copy/Start key  206  represents a single user command that is interpreted by digital copier  106  to request both copying and archiving. Thus by copying, the user achieves both copying and archiving. In one embodiment, the user may enter a lock-out code to inhibit archiving, for instance, for privacy-protection purposes. 
     Details of the hardware for the copying and archiving processes will be made clearer with reference to FIGS. 3-5. 
     FIG. 3 depicts a top-level diagram of digital copier  106  implementing automatic document archiving in accordance with one embodiment of the present invention. Digital copier  106  includes a scanner engine  302 , a print engine  304 , a controller  306 , a touch screen  308 , and an internal disk storage unit  310 . Controller  306  includes a DRAM unit  312 , an LZ image compressor  314 , a CPU  316 , an IDE controller  318 , a SCSI controller  320 , and a network interface  321 . A bus  323  interconnects the controller elements. Scanner engine  302  includes a scanner  302 A and an image processing unit  302 B. A video bus  324  interconnects scanner engine  302  and print engine  304 . An image data tap  326  provides controller  306  with access to image data transferred over video bus  324 . Controller  306  also takes advantage of an HSYNC signal  406  and a VSYNC signal  410  generated within print engine  304 . 
     Digital copier  106  accepts a document  328  and prints a copy  330  upon depression of Start/Copy key  206 . Scanner  302 A captures an image of document  328  and transmits the image to image processing unit  302 B; Image processing unit  302 B operates to remove distortion inherent in the scanning process. The output of the image processing unit is preferably in a format where 8 bits represent the grey-scale level of a pixel, there are 4380 active pixels per line, and there are 3380 active lines per frame or document page. There is a 10 pixel blanking period before and after each active line, making the total number of pixels per line, 4400. Similarly, there is a 10 line blanking period before and after every frame, making the total number of lines in a frame 3400. Of course, these parameters are only design choices. 
     This pixel data is forwarded from image processing unit  302 B to print engine  304  for printing. The data rate over video bus  324  is preferably 20 MHz. Controller  306  monitors video bus  324  via image data tap  326  to receive the same pixel data. Although, it would be possible to monitor the pixel data prior to image processing unit  302 B, the advantage to monitoring on video bus  324  is that image processing unit  302 B is tightly coupled to scanner  302 A and can monitor and correct for errors inherent in the scanning process. 
     Controller  306  performs overall control functions for digital copier  106  including the archiving functions. CPU  316 , an Intel 80960 CF microcontroller, operates the control program for the operation of digital copier  106 . Image data is often transferred into controller  306  at a faster rate via image data tap  326  than the image data can be archived. Accordingly, DRAM unit  312 , preferably incorporating 8 to 72 MB of DRAM, acts as a buffer for image data. This allows printing of the copy to continue without interruption by the archiving process. 
     To save on storage space and facilitate faster data transfer across network  100 , LZ image compressor  314  may compress the image data prior to archiving in accordance with the Lempel-Ziv image compression format. Of course, any image compression format may be chosen in accordance with the invention. With each block of image data to be archived, controller  306  incorporates the user ID data received from touch screen  308 . 
     The actual archiving of document images may occur either locally or remotely. Controller  306  may maintain the archive on disk storage unit  310 , in which case the image data will be transferred via IDE controller  318 . The archive may also be maintained either internally or externally on SCSI drives to which image data is transferred via SCSI controller  320 . Note, that if the archive is maintained on disk storage unit  310 , or a disk drive accessible via SCSI controller  320 , digital copier  106  will absorb some or all of the functionality of document management workstation  108 . If the archive is maintained on document management workstation  108 , network interface  321  sends the image data there via network  100  along with the user ID data for each particular document. Typically, LZ image compressor  314  is used in applications where documents are archived locally as opposed to remotely. 
     FIG. 4 depicts signals transferred over video bus  324  and image data tap  326  in accordance with one embodiment of the present invention. A pixel data line  327  carries the image data generated by image processing unit  302 B in a format to drive a laser diode input port  402  of print engine  304 . Each pixel includes 8 bits. 
     Print engine  304  operates in accordance with well-known laser xerography principles and incorporates a laser diode that varies in illumination intensity responsive to the document image to be printed. The 8 bits input to laser diode input port  402  includes 3 bits modulating the intensity of illumination of the laser diode and 5 bits modulating the width of illumination pulses. These pixels transfer over a pixel data line  327  at a 20 MHz rate. In the preferred embodiment, the image data presented at laser diode input port  402  is directly relayed to controller  306  via image data tap  326 . 
     The beam output of the laser diode passes through a system of lens and mirrors that generates the horizontal scanning action to sweep the beam over a rotating xerographic drum, thereby recreating the document image as a charge pattern on the drum. Typically, the rotation of a polygonal mirror tracks the scanning action. To assure the highest quality of reproduction, printing requires careful synchronization between the constituent parts of the scanner  302 A, image processing unit  302 B and the Print Engine  304 . This synchronization is signalled using the horizontal and vertical video synchronization signals, lines  404 ,  406 ,  408 , and  410 . All of these signals are interrelated in terms of synchronization to the motion inherent in the rotating polygonal mirror which provides faster scanning in the print engine, and in terms of the scanner  302 A. In some embodiments, the timing may be sourced by the print engine  304 , and circuitry in image processing unit  302 B is phase-locked to that timing. In an alternate embodiment, image processing unit  302 B may provide the master timing to the print engine  304 , which subsequently phase-locks or otherwise synchronizes its mechanical motion to these source signals. This embodiment is illustrated in FIG.  4 . Those skilled in the art will recognize the various trade-offs in product design originating from alternative selections of the master reference timing sources used for generating the synchronization signals in the system of FIG. 4, without losing the generality of obtaining access to the video bus  324 . 
     Horizontal synchronization signal (HSYNC)  406  for the image data may be obtained from print engine  304  in many ways. One technique is to position an optically sensitive sensor at a point within the optical system where the scanning action of the beam may be monitored. A pulse is generated every time the beam reaches an extremity of the scan. Depending on the particular design of the optical system, this pulse rate may be a harmonic or subharmonic of the actual horizontal synchronization rate. 
     Another technique is to attach an optical encoder to the motor that rotates the polygonal mirror. By monitoring the motor operation in this, or some other way, horizontal synchronization signal  406  may be derived. It is also possible to derive horizontal synchronization signal  406  from the control signal which drives the motor. 
     A vertical synchronization control  408  also incorporates information about the scanning action of scanner  302 A. To assure high quality reproduction, the movement of paper through print engine  304  takes this vertical synchronization control information into account. Vertical synchronization signal  410  may be obtained from print engine  304  in a variety of ways. One way is to tap off an internal signal that gates a new sheet of paper to pass underneath the xerographic drum. 
     The horizontal and vertical synchronization signals  406  and  410  are used to assure that only valid pixels are archived. Data indicating the number of lines on each page and the line length in pixels is also archived with the pixels. Thus, when the document is retrieved for printing later, printing of the document inherently takes advantage of the information present on vertical synchronization control  408  and horizontal synchronization control  404 , namely image position within a page, and more particularly, the size of paper printed upon. Furthermore, the document image has already been subject to sophisticated image processing by IPU  302 B. The final printed document is therefore a very high quality reproduction. 
     The present invention is however not restricted to capturing image data for archiving at the output of an image processing system such as IPU  302 B. Whether or not such an image processing system is present, image data for archiving may be captured at the output of scanner  302 A. 
     Automatic Archiving of Printed Documents 
     FIG. 5 depicts a simplified representation of a user interface screen  500  for operating a printer. A user interface screen such as screen  500  is generally displayed by client system  102  whenever the user requests printing of a document. A list  502  of options permits the user to select whether the full document is to be printed, only a specified range of pages, or only text that has been highlighted using a pointing and selection device such as a mouse. If a range of pages is to be specified, a field  504  is used to enter the range of page numbers. A field  506  permits the user to specify a number of document copies to be printed. A “current printer” field  508  identifies the printer that will be used to print the document. Activation of a “Close” screen button  510  dismisses user interface screen  500 . 
     In the prior art, activation of a “Print” screen button  512  causes a document to be printed. In accordance with one embodiment of the present invention, activation of “Print” button  512  represents a single user command to both print and archive the document. Client system  102  sends the document to be printed to print server  104  which runs print spooling software for writing to printer  112 . The print spooling software maintains a queue of print jobs to run. The document may be sent to print server  104  in any format, such as text, TIFF, GIF, postscript, etc. Printer  112  will typically accept postscript input but other printer configurations are also possible. If the format of transmission by client system  102  is different from the format accepted by printer  112 , printer server  104  will also perform format conversion. 
     In accordance with the invention, each document handled by print spooling software is sent to document management workstation  108 . The document may be transmitted in either the format generated by client system  102  or any format to which printer server  104  is able to convert. The document may be sent to document management workstation  108  with data identifying the current user of client system  102 . Thus, archiving becomes an incidental consequence of the printing process. Previously printed documents are retrievable. 
     Automatic Archiving of Faxed Documents 
     FIG. 6 depicts a simplified representation of a facsimile machine user interface  600 . A display screen  602  provides the user with prompts. A keypad  604  allows for entry of a telephone number to which a document is to be faxed. Depression of a start button  606  causes a document to be scanned into a memory within a facsimile machine or, if a document has already been scanned into memory and a telephone number has been entered, causes the document to be faxed to the entered telephone number. Depression of a stop button  608  causes faxing to cease. In accordance with the present invention, depression of start button  606  at the appropriate time represents a single user command to both fax and archive a document. 
     FIG. 7 depicts facsimile machine  110  modified for automatic archiving in accordance with one embodiment of the present invention. Facsimile machine  110  incorporates a scanner  702  for scanning a document to be faxed and storing a binary pixel representation of the document in a memory (not shown) internal to scanner  702 . A source coding unit  704  compresses the gray scale pixel data in accordance with facsimile transmission standard, e.g., Group III. A modem  706  modulates a carrier with the compressed data output of source coding unit  704  in accordance with the relevant facsimile transmission standard to generate a modulated signal to output on a telephone line  708 . 
     In accordance with one embodiment of the present invention, an image data tap  710  transmits the compressed data output of source coding unit to a network interface  712 . Network interface  712  in turn sends the compressed data output representing a document to document management workstation  108  for archiving. In a alternative embodiment, image data tap  710  is instead positioned at the output of scanner  702 . 
     Optionally, the user enters a code number on keypad  604  to identify himself or herself. This information is also sent to document management workstation  108  to be stored with the faxed document. Alternatively, the identity of the user of facsimile machine  110  is already known in some other way. 
     Thus, every document that is faxed is also archived without further user input. This provides yet another source of document images for the archive maintained by document management workstation  108 . 
     Document Management Workstation 
     FIG. 8 depicts a computer system  810  usable for implementing any one or more of client system  102 , print server  104 , or document management workstation  108  in accordance with one embodiment of the present invention. Computer system  810  includes bus  812  which interconnects major subsystems such as central processor  814 , system memory  816 , input/output (I/O) controller  818 , external device such as display screen  824  via display adapter  826 , serial port  828 , keyboard  830 , fixed disk drive  114  via a storage interface  832 , a serial port  834 , a CD-ROM player  836 , and a floppy-disk drive  838 . A mouse  840  may connect to serial port  828 . A network interface  842  for connection to network  100  may connect to serial port  834 . CD-ROM player  836  receives a CD-ROM disk  844 . Floppy-disk drive  838  receives a floppy disk  846 . Many other devices or subsystems (not shown) may be connected in a similar manner. Also, it is not necessary for all of the devices shown in FIG. 8 to be present to practice the present invention, as discussed below. The devices and subsystems may be interconnected in different ways from that shown in FIG.  8 . The operation of a computer system such as that shown in FIG. 8 is readily known in the art and is not discussed in detail in the present application. Source code to implement elements of the present invention may be operably disposed in system memory  816  or stored on storage media such as fixed disk  114 , floppy disk  846 , or CD-ROM  844 . 
     FIG. 9 depicts a software architecture  900  for operating a document image database in accordance with one embodiment of the present invention. Preferably, the software architecture operates on document management workstation  108 . Documents to be archived are received by a CFI (conversion of formats and indexing) module  902  from any one of digital copier  106 , print server  104 , or facsimile machine  110 . CFI module  902  converts the format of the received document to a desired format for storage. CFI module  902  may, e.g., receive the data in the 8 bit pixel format discussed in reference to digital copier  106  along with synchronization information useful for high quality reproduction. These desired formats include, e.g., postscript, 8 dpi GIFF, 72 dpi GIFF, 400 dpi TIFF, and plain text. Converting from a graphic format to plain text includes the process of optical character recognition. CFI module  902  also applies an indexing system to the documents to be archived. For plain text documents, the index information generated for the document facilitates later full text searching. If the identity of the user is available, this will also form a part of the indexing information for the document to facilitate later retrieval by the user. 
     For each document to be archived, a separate HTML document is generated with an iconic form of the images (8 dpi GIF) to be archived and keywords from a text document that is stored. One set of HTML index pages is maintained for each user. Each HTML index page in the set provides a different view of the images in a user&#39;s database. For example, one page provides a sequential listing of every saved image, including the document icons. Another page provides a sequential listing of all the documents which shows an ASCII summary of each image without showing the icons. CFI module  902  performs the necessary conversions. 
     An encryption module  904  optionally encrypts the document to be archived and its HTML counterpart with an encryption key particular to the user. This way only the user and other authorized parties may retrieve the encrypted document. The encrypted documents are stored on disk storage unit  114 . 
     An SRI module (search and retrieval interface) module  906  provides access to the document archive maintained on disk storage unit  114 . Decryption system  908  is provided as an option for encrypted documents. SRI module  906  is implemented as an HTTP daemon operating on document management workstation  108 . SRI module  906  is preferably the only search and retrieval path to the document archive. This restricted form of access allows log access information to be maintained. SRI module  906  processes HTTP requests from client system  102  to browse HTML documents on disk storage unit  114 , or to search and retrieve the archived documents. Full text search is implemented with a WAIS engine or other search engine (e.g., VERIFY, EXCALIBUR, FULCRUM) implemented with SRI module  906 . Queries are entered by the user in an HTML form and transmitted to the search engine using a CGI script running in SRI module  906 . An initial user request should incorporate a password to authorize decryption by decryption system  908 . 
     To facilitate user interaction with SRI module  906 , client system  102  preferably runs a Java-capable world wide web browser such as Netscape Navigator obtainable from Netscape Communications of Mountain View, Calif. Java programs may be downloaded from SRI module  906  to perform functions such as searching or display and printing of particular document formats. 
     Of course, the storage and retrieval architecture discussed above is only representative. The co-filed application “DOCUMENT MANAGEMENT SYSTEM” includes many other applications of an automatic archiving system. 
     In the foregoing specification, the invention has been described with reference to specific exemplary embodiments thereof. It will, however, be evident that various modifications and changes may be made thereunto without departing from the broader spirit and scope of the invention as set forth in the appended claims. Many such changes or modifications will be readily apparent to one of ordinary skill in the art. For example, digital copier  106  may also act as a printer for client system  102 . Also, the network  100  may include connections over a WAN or the Internet, allowing remote archiving and retrieval of documents. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense, the invention being limited only by the provided claims and their full scope of equivalents.