JP2005216240A - Print management system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To recognize changed contents when printing a print draft in which its contents are changed. <P>SOLUTION: A print management system memorizes PDL print data (print data described by a page description language) of a draft printed in the past. When printing of the draft is instructed by inputting the PDL print data of the print object draft, the print management system determines existence of any change by comparing both data if the PDL print data for the same draft printed in the past are memorized (affirmative answer at 102), and inquires of a print instructor about whether or not its change is regular by informing of changed contents (114) if any change is existed (affirmative answer at 108). The system cancels printing if the change is falsified (118), and adds data for printing changed contents on a printing matter to the PDL print data (124 or 128), and also executes RIP processing for evolving the PDL print data to bit-mapped print data (132) after registering the PDL print data to a data storing section (126 or 130). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a print management apparatus, and more particularly to a print management apparatus that manages a print target document to be printed by a printing apparatus.

  In printing at home and office, a relatively small number of many kinds of printed materials are often printed, and the size of the printed materials is limited (for example, A3 or lower), so that the electrophotographic process (xerography) is used as a printing apparatus. A color printer using is suitable. On the other hand, in the printing industry, for the purpose of printing a small number of kinds of printed matter in large quantities, conventionally, in most cases, a block was generated based on print data, and printing was performed using the generated block. Due to changes in the printing process due to the popularization of DTP (DeskTop Publishing / Prepress), the so-called “digital revolution of printing” has led to the adoption of “direct printing” or “on-demand printing” in which printing is performed directly from DTP data. ing. In direct printing (on-demand printing), pre-pressing without producing intermediate products such as paper printing (printing paper) such as photo-setting in traditional printing (for example, offset printing), block printing, net negative, net positive, PS plate, etc. By completely digitizing the process, a plate is directly created from print data (DTP data) by a plate making device (CTP: Computer To Plate), and printing is performed by setting the created plate on a printing press. .

  In addition, the above-described color printer and plate making apparatus can directly perform printing (preparation of a printing plate) from print data. Printing using a color printer and printing using a plate making apparatus (and a printing machine) are not possible. Since they have different characteristics, a printer and a plate making device are provided as printing devices, and these printing devices, terminals, and devices that perform processing such as rasterization (bitmap data) of print data are used as communication lines. And a printing system that allows a user to select whether to perform printing using a printer or a plate making apparatus in units of individual print jobs when a user instructs printing execution via a terminal. Construction is also being considered.

As a technique for preventing wasteful use of paper and improving the efficiency of print processing, Patent Document 1 discloses that control information is created for each print page, and the created control information is output to a printing apparatus for printing. When the replacement print mode is selected as the print mode, the created control information is compared with the stored processed information, and the control information is sent to the printing device only when the comparison result does not match. A technique has been disclosed that realizes replacement printing that automatically prints only corrected pages in a document when a part of the document is corrected and reprinted by outputting.
JP 2002-63012 A

  By the way, as a usage form of the above-described printing system, for example, when a document is finally printed, a plate making apparatus (and a printing machine) is used. For printing when a simple page is inserted, a printer may be used. However, a document that is finally printed by a plate making apparatus (and a printing machine) is externally supplied by a client who desires a printed matter of the document. Most of the processes such as design / editing (DTP), proofreading, imposition, color proofing, etc. are carried out by external contractors. In this form, since many people are involved in the production of the original document to be printed, it is highly likely that the data of the original document to be printed is placed in an environment where an unspecified person can change in the middle of the process. The manuscript may be altered by the three parties.

  For this reason, there is a need for grasping how the content of a document to be printed has been changed. In addition, if it is possible to grasp how the contents of the document to be printed have been changed, the cause of the image printing, for example, when an image defect such as white spots, garbled characters, or black solids occurs on the printed material, is also the cause. It becomes possible to investigate. On the other hand, the technique described in Patent Document 1 described above saves labor when the print instructor who grasps the change contents by changing the document by himself / herself prints only the changed page of the document. However, it does not contribute to the understanding of changes in an environment where many people are involved in the production of manuscripts, and the above-mentioned needs cannot be satisfied.

  The present invention has been made in consideration of the above facts, and an object of the present invention is to obtain a print management apparatus capable of recognizing changed contents when printing a document whose contents are changed.

  In order to achieve the above object, a print management apparatus according to the first aspect of the present invention includes a storage unit that stores information on a document that has been printed in the past, and a print target document that is instructed to be printed by the printing apparatus. In the case where the document has been printed in the past, the data to be printed is compared with the information on the same document stored in the storage unit, so that the document to be printed is A determination means for determining whether or not the content has been changed, and when the determination means determines that the content of the document to be printed has been changed, notifies that the content of the document to be printed has been changed, or Change notification means for outputting change content information representing the change content in the original document to be printed.

  According to the first aspect of the present invention, information on a document that has been printed in the past is stored in the storage unit, and the determination unit prints a document to be printed instructed to be printed by the printing apparatus in the past. In the case of the original document, it is determined whether the content of the original document to be printed has been changed since the past printing by comparing the data of the original document to be printed with information on the same original document stored in the storage unit. . The change notifying unit notifies that the content of the print target document has been changed when the determination unit determines that the content of the print target document has been changed, or the change content indicating the change content in the print target document. Output information.

  Thereby, when printing a document whose contents have been changed, the changed contents can be recognized by a print instructor or the like. Therefore, even when a print target document is falsified by a malicious third party, the print instructor or the like can be grasped, and even when an image defect occurs in the print result of the print target document, The cause can be easily investigated.

  In the first aspect of the present invention, print data described in, for example, a page description language is input as the data of a document to be printed, and the printing apparatus performs printing using bitmap data obtained by expanding the print data. It can be carried out. In this case, as described in claim 2, the storage unit stores print data (print data described in a page description language) as document information, and the determination unit stores the print data of the input print target document. Is compared with the print data of the same document stored in the storage means, so that it can be determined whether or not the content of the document to be printed has been changed since the previous printing.

  As described above, by comparing the print data described in the page description language and determining whether or not the content has been changed, for example, the addition or deletion of the page of the document to be printed described in claim 3, Application used to change the character itself existing in the document, change the position or size of the character, change the font of the character, change the position or thickness of the line drawing existing in the document to be printed, and create the document to be printed It is possible to determine whether or not there is a content change for each change item of the change, and by configuring the determination means to determine whether or not there is a content change for at least one of the change items, the content is changed. When printing an existing document, the change content can be recognized by the print instructor or the like in more detail.

  In the first aspect of the present invention, print data described in a page description language, for example, is input as print target document data, and the printing apparatus performs printing using bitmap data obtained by expanding the print data. For example, as described in claim 4, the storage unit stores bitmap data or characteristic information obtained from the bitmap data as document information, and the determination unit stores the input print data of the document to be printed. By comparing the bitmap data obtained by the development or the feature information obtained from the bitmap data with the bitmap data of the same document stored in the storage means or the feature information obtained from the bitmap data, It may be determined whether the contents of the document to be printed have been changed since the past printing. In this case, it is difficult to distinguish each change item as described in claim 3 when determining whether or not the content of the document to be printed has been changed, but whether or not to change the content of the document to be printed. The location where has been changed can be detected (determined) and notified.

  In the invention described in claim 4, for example, a checksum can be used as the feature information obtained from the bitmap data. In this case, the determination means is obtained from the bitmap data as described in claim 5, for example. By comparing the checksums calculated for the respective bitmap data to be compared as feature information, it is possible to determine whether or not the contents of the document to be printed have been changed since the past printing. The above checksum calculation may be performed in units of one line, for example, or may be performed by applying other units such as a plurality of lines. As described above, by using the checksum as the feature information, the storage capacity of the storage unit can be reduced and the time required for the determination by the determination unit can be shortened.

  Further, in the first aspect of the invention, the change notification means, as described in, for example, claim 6, when the determination means determines that the content of the print target original has been changed, The information about the document to be printed is stored in the storage means only when the content change of the document to be printed is inquired about whether it is a legitimate change (that is, whether it is not falsification) and notified that it is a legitimate change. It is preferable to make it memorize | store. An inquiry about whether or not the content change of the document to be printed is a regular change can be made, for example, to the print instructor, and the regular change by the print instructor or the like based on the change content of the document to be printed It is notified whether or not. In the invention described in claim 6, information on a document to be printed (for example, print data described in claim 2 or bitmap data or feature information described in claim 4 is provided only when it is notified that the change is a regular change. ) Is stored in the storage means, it is prevented from determining whether or not the content of the document has been changed with reference to the altered content, and the determination can be made accurately.

  Further, in the invention described in claim 1, the change notification means performs a process of printing the change content information together with the document to be printed by the printing apparatus as a process of outputting the change content information, for example, as described in claim 7. be able to. As a result, it is possible to make the print instructor who refers to the print result of the document to be printed recognize the change content represented by the change content information. In the invention described in claim 7, the change content information is printed by the change notification means, specifically, in a place corresponding to the margin of the printed material on which the document to be printed is printed as described in claim 8, for example. The change content information can be printed, or the change content information can be printed on a printed matter in a color that is difficult to view.

  Further, in the invention described in claim 7, the change notification means stores the change content information in the storage means every time the determination means determines that the content of the document to be printed has been changed, as described in claim 9, for example. At the time of printing the change content information, it is preferable to read and print all the change content information stored in the storage means for the same document. As a result, it is possible for a print instructor or the like who refers to the print result of the print target document to grasp the contents of all changes (change history) made to the print target document in the past.

  The printing apparatus according to claim 1 may be, for example, a printer that directly prints a print target document on a recording medium by an electrophotographic process, or a printer for printing a print target document on a recording medium. Although a plate making apparatus for producing a printing plate may be used, for example, as described in claim 10, the print management apparatus according to the present invention may be connected to the printer and the plate making apparatus as a printing apparatus. The present invention can also be applied to an environment in which a printer or a plate making apparatus is designated as a printing apparatus for printing a document to be printed and printing is instructed.

  As described above, according to the present invention, information on a document that has been printed in the past is stored in the storage unit, and the data of the document to be printed is stored when the document to be printed is a document that has been printed in the past. Is compared with the information of the same document stored in the storage means to determine whether the content of the document to be printed has been changed since the past printing, and it has been determined that the content of the document to be printed has been changed. In such a case, the change content is notified or the change content information indicating the change content is output, so that the change content can be recognized when printing the document whose content has been changed. It has an excellent effect.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a printing system 10 according to the present embodiment. The printing system 10 includes, as a printing apparatus, an image forming apparatus 12 that functions as a printer that forms a visible color image on a predetermined recording sheet by an electrophotographic process based on input print data, and a printing machine (press apparatus) 14. Is provided with a plate making apparatus (CTP: Computer To Plate) 16 for directly creating a printing plate for printing from input print data. The image forming apparatus 12 and the plate making apparatus 16 correspond to the printing apparatus according to the present invention. Specifically, the image forming apparatus 12 is a printer according to claim 10, and the plate making apparatus 16 is according to claim 10. It corresponds to each plate making device.

  The image forming apparatus 12 and the plate making apparatus 16 are connected to a BEP (BackEnd Processor) 20 via communication lines 18A and 18B. The BEP 20 shows a large number of client terminals 22 (in FIG. 1, only a single client terminal 22 is shown). ), RIP (Raster Image Processor) 24, server computer 25, and communication line 26 (for example, a high-speed wired LAN (Local Area Network) using a general-purpose communication protocol with a communication speed of about 1 Gbps (Gigabit per second)). Are connected to each other. Note that the printing system 10 can be connected to a scanner device that reads an image of a document and outputs image data, and a printer proofer for confirming print output.

  As the plate making apparatus 16, for example, a sheet-shaped printing plate is wound around and fixed to the outer peripheral surface of a cylindrical rotating drum, and the rotating drum is rotated and modulated according to the input print data of the specific color component. A printing plate (printing plate) with a specific color component is developed by recording a printing image on the printing plate by irradiating a printing plate rotating integrally with a rotating drum with a light beam, and then developing the printing plate on which the printing image is recorded. The structure which manufactures can be employ | adopted. In this case, a printing plate corresponding to each color component can be obtained by repeating the above process for each color component of C, M, Y, and K. The printing plates of the respective color components produced by the plate making device 16 are set in the printing machine 14 and used for printing.

  A print instruction in the printing system 10 according to the present embodiment is print data in which a print image to be printed is described in a page description language (PDL) (hereinafter, print data described in PDL is referred to as PDL print data). ) Is transmitted from the client terminal 22 to the RIP 24. The server computer 25 stores print control information corresponding to individual print data. The print control information according to the present embodiment is information that conforms to a predetermined format (for example, JDF: Job Definition Format). In addition to information such as a printing apparatus that performs printing, the number of copies, the size of printed matter, and paper quality, the plan・ Comprehensive information on printed matter production from production to delivery (for example, production specifications of printed matter, processing procedures in each process such as production, printing, and post-processing, individual print jobs, process status and history, etc.) It is said that.

  The RIP 24 is configured by a computer such as a personal computer (PC), and includes a data storage unit 30, a RIP processing unit 32, a compression processing unit 34, and an interface (I / F) unit 36 as shown in FIG. Yes. The data storage unit 30 sequentially stores PDL print data (specifically, print data described in PDL and expressing colors in R, G, and B) received by the RIP 24 from the client terminal 22. The RIP processing unit 32 incorporates a PDL interpretation unit and a decomposer functioning as an imager, a so-called RIP engine. The RIP processing unit 32 extracts the PDL print data from the data storage unit 30 and interprets it, and performs color conversion of R, G, B → C, M, Y, K and raster image data (bitmap format data). RIP (Raster Image Process) processing for generating print data that can be used for printing on a printing apparatus is performed in units of pages.

  The print data used for printing on the image forming apparatus 12 and the print data used for printing on the plate making apparatus 16 (preparation of printing plates) have different formats (for example, printing on the image forming apparatus 12). The print data used is data that represents a gradation with 8 bits each of C, M, Y, and K at a resolution of 600 dpi, whereas the print data used for printing by the plate making apparatus 16 has a resolution of 2400 dpi. Or 4800 dpi, 1 bit each of C, M, Y, K data per dot (data to express gradation in units of multiple dots, etc.), RIP processing unit 32 conforms to the type of printing device specified Print data in the format specified.

  In addition, the RIP processing unit 32 refers to the parameters set in the print control information corresponding to the PDL print data extracted from the data storage unit 30, and prints according to the processing conditions of the print job corresponding to the extracted PDL print data. A process to be executed at times is determined, and among the determined processes, processes related to the RIP process are simultaneously performed. As processing related to the RIP processing, for example, if the designated printing apparatus is the image forming apparatus 12, for example, rotation (Rotation), page allocation (N-UP) in one sheet, and repeat processing , Paper size adjustment, CMS (Color Management System) processing to correct device differences, resolution conversion, contrast adjustment, compression rate designation (low / medium / high), etc. If it is the apparatus 16, a screen process etc. are mentioned.

  The print data obtained by performing the above-described various processes in the RIP processing unit 32 is reprinted using the same print data (for example, in the printing by the image forming apparatus 12, collation). The data is stored in the data storage unit 30 in preparation for printing a plurality of copies depending on the setting, or for determining whether or not the content has been changed (described later).

  The compression processing unit 34 generates a compressed image file by compressing the print data generated by the RIP processing unit 32 using a predetermined compression method. The print data to be compressed is separated into data corresponding to the line drawing portion of the print image represented by the print data and data corresponding to the background portion of the print image, and the data of the separated line drawing portion and the data of the background portion are separated. Are compressed by different compression methods (for example, lossless compression (lossless compression) is applied to line drawing data and lossy compression is applied to background data). May be configured. Further, the I / F unit 36 transmits the compressed image file output from the compression processing unit 34 to the BEP 20 via the communication line 26 as print file data in a predetermined format (for example, TIFF (Tagged Image File Format) format) (for example, File transfer using FTO (Fast Transfer Protocol).

  Next, the configuration of the BEP 20 will be described. The BEP 20 is also composed of a computer such as a PC. As shown in FIG. 2, the BEP 20 includes a data receiving unit 40, an image storage unit 42, an expansion processing unit 44, an image processing unit 46, I / F units 48 and 50, and a print control unit 52. The data receiving unit 40 receives the print file data transmitted from the RIP 24, the image storage unit 42 sequentially stores the print file data received by the data receiving unit 40, and the decompression processing unit 44 has a predetermined order (for example, image storage). The print file data is read from the image storage unit 42 in the order of storage in the unit 42), and the compressed image file is extracted from the read print file data and decompressed. On the other hand, when the expansion processing unit 44 reads specific print file data from the image storage unit 42, the print control unit 52 print control information corresponding to the specific print file data (print stored in the server computer 25). Control information), the operation of each unit of the BEP 20 is controlled in accordance with the print job processing conditions defined by the parameters set in the print control information.

  In other words, the image forming apparatus 12 is connected to the expansion processing unit 44 through the I / F unit 48 and the image processing unit 46, and the plate making apparatus 16 is connected to the expansion processing unit 44 through the I / F unit 50. Based on whether the designated printing device is the image forming device 12 or the plate making device 16, the print control unit 52 converts the print image data obtained through the expansion processing by the expansion processing unit 44 into the image processing unit 46 or the I / F unit. 50. When the designated printing apparatus is the plate making apparatus 16, the print image data output from the expansion processing unit 44 is input to the I / F unit 50. The BEP 20 and the plate making apparatus 16 are in a relatively “sparse” relationship in which communication is performed using a general-purpose communication protocol. Print image data input to the I / F unit 50 is printed by the plate making apparatus 16. Print data to be created is sequentially transferred to the plate making apparatus 16 by a general-purpose communication protocol, and used for printing (creating a printing plate) by the plate making apparatus 16.

  On the other hand, when the designated printing apparatus is the image forming apparatus 12, the print image data output from the expansion processing unit 44 is input to the image processing unit 46. The image processing unit 46 has a function of performing various processes such as rotation, adjustment of the print position of the print image on the paper, enlargement or reduction of the input print image data, and the print control unit 52 performs printing. Sorting pages in ascending / descending order according to the discharge conditions specified by the parameters set in the control information and the structure and characteristics of the image forming apparatus 12 that performs printing, determining the processing page order during duplex printing, Page rearrangement corresponding to calibration processing such as color conversion, gray balance correction, and color shift correction using a multi-dimensional lookup table (DLUT), screen designation processing, and finishing processing executed by the finisher module of the image forming apparatus 12 (Securing the location of the stapler and punch holes), collation (collation), discharge surface (upper and lower) alignment, etc. To perform various types of processing which the processing contents are different depending on the concrete and the characteristics in the image processing unit 46.

  The BEP 20 and the image forming apparatus 12 have a relatively “close” relationship in which communication is performed using a dedicated communication protocol (a communication protocol depending on the print engine of the image forming apparatus 12). The processed print image data is transferred to the image forming apparatus 12 via the I / F unit 48. At the time of transfer of the print image data, the print control unit 52 controls the operation of each unit of the image forming apparatus 12 by sending various control commands at a timing synchronized with the processing speed of the image forming apparatus 12, thereby forming an image. The printing process is executed by the device 12. In addition, the print control unit 52 automatically performs recovery processing at the time of a paper jam in which the processing contents differ depending on the structure and characteristics of the image forming apparatus 12. Thus, the print control unit 52 also functions as a printer controller that controls the operation of the image forming apparatus 12.

  Next, as an operation of the present embodiment, the print instruction person transfers the data (PDL print data) of the document to be printed from the client terminal 22 to the RIP 24 to instruct printing, and the PDL print data is stored in the data storage unit 30 of the RIP 24. The change monitoring process executed by the RIP processing unit 32 of the RIP 24 when the RIP process is performed after being stored in the RIP will be described with reference to the flowchart of FIG. In the present embodiment, the RIP 24 that executes this change monitoring process corresponds to the print management apparatus according to the present invention.

  In step 100, the PDL print data to be printed is extracted from the data storage unit 30, and the file name given to the extracted PDL print data to be printed is recognized. In the next step 102, it is determined whether or not PDL print data having the same file name as that recognized in step 100 is stored in the data storage unit 30. As will be described below, in this embodiment, PDL print data of a document that has been printed in the past by the printing system 10 is stored in the data storage unit 30. Therefore, in step 102 described above, it is determined whether the PDL print data to be printed is data of a document that has been printed in the past. Thus, in the present embodiment, the data storage unit 30 corresponds to the storage means described in claim 1 (specifically, claim 2).

  If the determination in step 102 is negative, it can be determined that the PDL print data to be printed is data of a document that has not been printed by the printing system 10 in the past. PDL print data is registered in the data storage unit 30 in association with information such as a file name, registration date (current date), and file size. Thereby, when reprinting in the printing system 10 is instructed for the original document to be printed this time, the determination in step 102 is affirmative based on the information registered in the data storage unit 30 in step 104. Will be. An example of information registered / saved in the data storage unit 30 is shown in the following Table 1 (although change history information will be described later, PDL print data of each original document is first registered in the data storage unit 30) Is not added).

  When the process of step 104 is performed, the process proceeds to step 132, where RIP processing for expanding the PDL print data to be printed into bitmap format print data (raster image data) is performed, and the change monitoring process ends. The print data obtained by the processing in step 132 is subjected to image processing corresponding to the designated printing apparatus, and then compressed by the compression processing unit 34, and is printed as I / F as print file data in a predetermined format such as TIFF. The data is transferred from the unit 36 to the BEP 20.

  On the other hand, if the determination in step 102 is affirmative (if the PDL print data to be printed is data of a document that has been printed in the past), the process proceeds to step 106 and is registered and stored in the data storage unit 30. The PDL print data having the same file name (PDL print data used for the previous printing of the same document) is taken out, the command described in PDL in the PDL print data to be printed, and the previous PDL print data Compare instructions written in PDL. In step 108, based on the comparison result in step 106, it is determined whether or not the PDL print data to be printed has been changed from the previous PDL print data.

An example (part) of PDL print data described by PostScript, which is one of PDL, is described below.
"50 600 moveto" (move the pointer to the position of x = 50, y = 600)
"/ Times-BoldItalic findfont" (specify "Times-BoldItalic" font)
"12 scalefont setfont" (font size: specify 12 points)
"(ABCabc) show" (character string "ABCabc" is output (display / print))
The PDL print data is data for displaying or printing the character string “ABCabc” at the position of x = 50, y = 600 using the 12-point font “Times-BoldItalic”. If changed, the data in the first row is
"50 700 moveto" (move the pointer to the position of x = 50, y = 700)
When the character size is changed, the data on the third line is
"18 scalefont setfont" (font size: specify 18 points)
When the character string is changed, the data on the fourth line is
"(ABDabd) show" (outputs the string "ABDabd" (display / print))
Will be changed.

  In the above description, the detection of the change of the character position, font type, size, and the character itself is taken as an example. By comparing the PDL print data, the addition or deletion of pages in the document to be printed, the document to be printed A change in the position or thickness of a line drawing existing inside can also be detected. Therefore, by comparing the PDL print data, whether or not the document represented by the PDL print data to be printed has been changed since the previous printing, and the change contents when the PDL print data to be printed have been changed. Can be detected. Thus, the above-described steps 106 and 108 correspond to the judging means described in claim 1 (specifically, claims 2 and 3).

  If the PDL print data to be printed has been changed from the previous PDL print data, the determination at step 108 is affirmed and the routine proceeds to step 114. The processing subsequent to step 114 corresponds to the change notification means described in claim 1 (specifically claims 6 to 9). In step 114, the print instructor instructed to print the document to be printed is printed. The detected change contents of the target PDL print data are notified, and a check is made to the print instructor as to whether or not the change is a regular change. This is because, for example, a message (for example, “a character has been changed” or “a font type (or size) of a character) notifying the detected change on the display of the RIP 24 or the display of the client terminal 22 operated by the print instructor. ”Has been changed”, etc.), the detected change on the document to be printed represented by the PDL print data is clearly displayed, and the original is displayed, and whether the specified change is a regular change or not. This message can be realized by displaying a message for requesting a check (for example, “Please confirm whether the contents of the specified changes are legitimate changes”).

  When the above notification is made, the print instructor recognizes that the document to be printed has been changed since the previous printing, and confirms the specified changes so that the detected changes can be confirmed. It is determined whether or not the change is known (that is, whether the change made to the document to be printed is a regular change). Then, the determination result is input via the RIP 24 or the keyboard of the client terminal 22. In the next step 116, it is determined based on the information input by the print instructor whether or not the change detected for the document to be printed is a regular change.

  When a change that the print instructor does not grasp is added to the document to be printed, it can be determined that there is a high possibility that the document to be printed has been falsified by a malicious third party. For this reason, if the determination in step 116 is negative, the process proceeds to step 118, and printing of the document to be printed is stopped (processing necessary for printing the document, such as RIP processing), and the next step In 120, a message warning the print instructor that the document to be printed is likely to be falsified by a third party is displayed on the display of the RIP 24 or the client terminal 22, and the change monitoring process is terminated.

  As a result, it is possible to prevent a manuscript that is likely to be tampered with from being inadvertently printed, and the print instructor confirms a change place on the manuscript to be printed, and if necessary, You can take measures such as undoing changes. If the determination in step 116 is negative, the PDL print data stored in the data storage unit 30 is not updated, so that the falsification is used to determine whether or not the content of the document is changed at the next printing. The PDL print data of the document that is likely to be printed is not used, and it is possible to accurately determine whether or not the content of the document has been changed.

  On the other hand, if the change made to the document to be printed is a change known by the print instructor, the determination in step 116 is affirmed and the process proceeds to step 122 to deal with the document to be printed. It is determined whether the change history information to be stored is stored in the data storage unit 30. In the present embodiment, for a document that is detected to have been subjected to a regular change when printing has been instructed in the past, information representing the change content detected in the past is stored in the data storage unit 30 as change history information. Stored. When the change history information does not exist (when the regular change detected this time is the first regular change related to the document to be printed), the determination in step 122 is negative and the process proceeds to step 128 to detect. Data specifying the change contents on the printed matter is added to the PDL print data to be printed.

  As this data, for example, as shown in FIG. 4A, data that clearly indicates the detected change contents as characters in the margin of the printed matter can be applied. In FIG. 4A, when printing a document to be printed one page at a time on one sheet of recording paper, the font of the character string “aiueo” in a specific page of the document to be printed is changed from “Mincho” to “ In addition to the change to “Gothic”, the numerical value “¥ 10,000” in the document to be printed has been changed to “¥ 10,500”. In addition to the effective area (area used as printed matter) specified by 70, an example is shown in which the character string “font change, numerical value changed” representing the above-mentioned change content is printed. In step 128, data for printing the character string as described above can be added to the PDL print data. When printing a plurality of pages of a document to be printed on one sheet of recording paper, for example, as shown in FIG. 4B, a character string (in the figure, “ page4: ”is equivalent to that).

  Further, the data added to the PDL print data to be printed in step 128 is not limited to the data for printing the character string as described above. For example, as shown in FIG. It is also possible to apply data that specifies the content as a two-dimensional barcode in the margin of the printed material. In FIG. 5A, as in the case of FIG. 4A described above, when the original document to be printed is printed one page at a time on one recording sheet, the characters “Aiueo” in a specific page of the original document to be printed. Record that the specific page was printed because the font of the column was changed from "Mincho" to "Gothic" and the numerical value "\ 10,000" in the document to be printed was changed to "\ 10,500" An example is shown in which a two-dimensional bar code representing the above-mentioned change (font change, numerical value change) is printed outside the effective area of the paper. In step 128, the above two-dimensional bar code is printed. Data for making it possible may be added to the PDL print data. When printing a plurality of pages of a document to be printed on one sheet of recording paper, for example, as shown in FIG. 5B, a two-dimensional bar to which information that can identify a specific page that has detected a change is added. Data for printing a code (for example, a two-dimensional bar code representing “number changed on page 4”) may be added.

  In the next step 130, the PDL print data of the document to be printed is registered in the data storage unit 30 in association with the file name, registration date (current date), and change content information (change history information) representing the detected change content. To do. If information such as PDL print data of a document to be printed is already registered in the data storage unit 30, the above information is registered by overwriting the already registered information. When the process of step 130 is performed, the process proceeds to step 132, where the RIP process for expanding the PDL print data to be printed into the bitmap format print data is performed, and the change monitoring process ends. In this case, the above-described print data is transferred to the BEP 20 through predetermined image processing and compression processing, so that the change detected this time for the document to be printed is included in the margin of the printed matter obtained by printing with the printing apparatus. A character string representing or 2D barcode is printed.

  Therefore, the print instructor can grasp how the content of the document to be printed has been changed this time by reading the character string or the two-dimensional barcode printed in the margin of the printed material. In addition, even when image defects such as white spots, garbled characters, black solids, etc. occur on the printed matter obtained by printing with the printing apparatus, by analyzing the changes to the document to be printed, It is possible to easily identify the content change that caused the problem, and to easily take measures such as correcting the PDL print data of the document to be printed so that the image defect is eliminated.

  If the change history information corresponding to the document to be printed has been stored in the data storage unit 30, the determination in step 122 is affirmed, and the process proceeds to step 124. Data specifying the past change history of the document to be printed represented by the change history information as a character string or a two-dimensional barcode is added to the PDL print data to be printed. The additional data is preferably data that clearly indicates the date and time when the change is detected in association with each change content. In the next step 126, information obtained by adding the change content information indicating the change content detected this time to the already registered change history information is set as new change history information, and the PDL print data to be printed is set as a file name, a registration date and time (current Date and time) and registered in the data storage unit 30 in association with the new change history information.

  When the process of step 126 is performed, the process proceeds to step 132, where the RIP process for expanding the PDL print data to be printed into the bitmap format print data is performed, and the change monitoring process ends. In this case, the above-described print data is transferred to the BEP 20 through predetermined image processing and compression processing, so that the detected contents of the original to be printed and A character string or a two-dimensional barcode representing the change content (change history) detected in the past is printed. Therefore, the print instructor can grasp the history of the content change of the document to be printed based on the character string or two-dimensional barcode printed in the margin of the printed material, and image defects have occurred on the printed material. Even in this case, it is possible to easily identify the content change that causes the image defect.

  On the other hand, if no change in the PDL print data to be printed with respect to the previous PDL print data is detected in the determination in step 108 described above, the process proceeds from step 108 to step 110 to deal with the document to be printed. It is determined whether the change history information to be stored is stored in the data storage unit 30. If the determination in step 110 is negative, the process proceeds to step 132 without performing any processing. Therefore, for a document whose content has not been detected this time and has not been detected in the past, print it with the printing device. No character string or two-dimensional bar code is printed in the margin of the printed matter obtained.

  If the change history information corresponding to the document to be printed is stored in the data storage unit 30, the determination in step 110 is affirmed and the process proceeds to step 112, and the past history information indicated by the registered change history information is displayed. After adding data specifying the change history as a character string or a two-dimensional barcode to the PDL print data to be printed, the process proceeds to step 132. Therefore, even if no change has been detected for the document to be printed this time, if the change has been detected in the past, the content of the change is clearly indicated on the printed matter as a character string or a two-dimensional barcode. It will be.

  In the above, by comparing the PDL print data, the addition or deletion of the page of the document to be printed, the change of the character itself existing in the document to be printed, the change of the position or size of the character, the font type of the character Although an example of detecting a change or a change in the position or thickness of a line drawing existing in a document to be printed has been described, when creating PDL print data, information such as the name of the application used to create the PDL print data is also included in the PDL. By adding it to the print data, it is possible to detect a change in the application used to create the document to be printed based on the information. Further, the present invention is not limited to detecting all the various changes listed above. For example, only a specific type of change may be detected, such as detecting only a change of the character itself.

  Further, in the above description, an example in which a change content detected for a document to be printed, a character string representing a past change history, or a two-dimensional barcode is printed in the margin of the printed matter (outside the effective area) has been described. Instead of the above, the character string or the two-dimensional barcode may be printed in an effective area on the printed material with a color that is difficult to visually recognize (for example, yellow).

  In the above description, an example of detecting a change in a document to be printed using PDL print data has been described. However, the present invention is not limited to this, and bitmap format print data obtained by developing PDL print data. It is also possible to detect changes in the document to be printed using. Hereinafter, an aspect of detecting a change of a document to be printed using bitmap format print data will be described. In this aspect, after the RIP processing unit 32 of the RIP 24 performs the RIP processing on the PDL print data to be printed, the checksum addition processing shown in FIG. 6 is performed.

  In this checksum addition process, first, in step 140, the bitmap format print data obtained from the PDL print data to be printed by the RIP process is fetched. In the next step 142, one line of data is fetched from the print data. . In step 144, a checksum is calculated for the extracted data for one line. In the next step 146, markers (for example, FFD0h etc.) are separated before and after the extracted data for one line. In the next step 148, the checksum calculated in step 144 is added to the end of the data for one line. In the next step 150, it is determined whether or not the above processing has been performed on the data for all lines. If the determination is negative, the process returns to step 142, and steps 142 to 150 are repeated until the determination is positive. If the determination in step 150 is affirmative, the checksum addition process is terminated. As a result, a marker and a checksum are added to the print data in units of one line of data.

  On the other hand, in the BEP 20 that receives the print data (compressed compressed image file) with the marker and checksum added as described above as a print image file, the change monitoring process shown in FIG. 7 is performed. In this aspect, the BEP 20 that executes the change monitoring process corresponds to the print management apparatus according to the present invention.

  In the change monitoring process shown in FIG. 7, first, in step 160, the print image file to be printed is extracted from the image storage unit 42, and in the next step 162, the decompression process is performed on the compressed image file included in the extracted print image file. The unit 44 performs decompression processing to obtain bitmap-format print image data. The processing after the next step 164 is processing realized by the image processing unit 46. First, at step 164, the print image data obtained by the expansion processing at step 162 is added to each line of the data. By recognizing the data break of each line based on the marker, the checksum added to each line is recognized, and the checksum of each recognized line is taken out as checksum data and included in the print image data Delete the marker and checksum.

  In step 166, the file name assigned to the print image data to be printed is recognized, and it is determined whether or not the same file name as the recognized file name is stored in the image storage unit 42. In this aspect, checksum data of a document that has been printed in the past by the printing system 10 is stored in the image storage unit 42 in association with the file name of the print image data. Therefore, in step 166, it is determined whether or not the print image data to be printed is data of a document that has been printed in the past. Thus, in this aspect, the image storage unit 42 corresponds to the storage unit according to claim 1 (specifically, the “storage unit storing feature information” according to claim 4).

  If the determination in step 166 is negative, the process proceeds to step 178, and the image storage unit 42 associates the checksum data extracted in step 164 with the file name, registration date (current date), and file size of the print image data. Register with. As a result, when reprinting in the printing system 10 is instructed for the original document to be printed this time, the determination in step 166 is affirmative based on the information registered in the image storage unit 42 in step 178. Will be. An example of information registered / stored in the image storage unit 42 is shown in Table 2 below.

  In the next step 180, the print image data to be printed (print image data from which the marker and checksum have been deleted) is transferred to the designated printing device, so that the printing device performs the printing process, and the change monitoring process is performed. finish.

  On the other hand, if the document to be printed is a document that has been printed in the past by the printing system 10, the determination in step 166 is affirmed and the process proceeds to step 168, and the same file name as the print image data to be printed is entered. Corresponding checksum data (checksum data calculated and added to print image data used in printing performed in the past) is taken out from the image storage unit 42, and the checksum data taken out is printed. The checksum data of the print image data (checksum data extracted in step 164) is compared with each line as a unit. In the next step 170, it is determined whether or not the checksums do not match. Steps 168 and 170 correspond to the judging means described in claim 1 (specifically, claims 4 and 5). If the determination in step 170 is negative, it can be determined that the document to be printed has not been changed since it was last printed by the printing system 10, so that in step 178, checksum data and the like are registered in the image storage unit 42. In 180, the print image data to be printed is transferred to the designated printing device, so that the printing device performs the printing process, and the change monitoring process ends.

  If there is a line whose checksum does not match, it can be determined that the line in the document to be printed has been changed since it was printed last time by the printing system 10. For this reason, when the determination of step 170 is affirmed, the routine proceeds to step 172. The processing after the next step 172 corresponds to the change notification means described in claim 1 (specifically, claim 6). In step 172, a checksum is given to the print instructor who instructed printing of the document to be printed. Notify that there is a mismatched line, and request the print instructor to check whether the change for the line is a regular change. This is because, for example, on the display of the BEP 20 or the display of the client terminal 22 operated by the print instructor, the checksum mismatch line is clearly displayed and the document to be printed is displayed, and the specified line is changed. Message (for example, "Any change has been made to the specified line") is displayed, and a request is made to check whether the change applied to the specified line is a legitimate change. This can be achieved by displaying a message (for example, "Please check if the changes made to the specified line are legitimate changes").

  By performing the above notification, the print instructor recognizes that the document to be printed has been changed since the previous printing, and confirms the change made to the specified line, thereby confirming the change. It is determined whether or not the change is a change content that the user knows (that is, whether or not the change made to the document to be printed is a regular change). Then, the determination result is input via the BEP 20 or the keyboard of the client terminal 22. In the next step 174, based on the information input by the print instructor, it is determined whether or not the change applied to the line whose checksum does not match is a regular change.

  When a change that the print instructor does not grasp is added to the document to be printed, it can be determined that there is a high possibility that the document to be printed has been falsified by a malicious third party. Therefore, if the determination in step 174 is negative, the process proceeds to step 176, printing of the document to be printed is stopped, and the change monitoring process is terminated. As a result, it is possible to prevent a manuscript that is likely to be tampered with from being inadvertently printed, and the print instructor confirms a change place on the manuscript to be printed, and if necessary, You can take measures such as undoing changes. If the determination in step 174 is negative, the checksum data stored in the image storage unit 42 is not updated, so that the falsification is used to determine whether or not the content of the document is changed at the next printing. The checksum data of the document that is likely to be printed is not used, and it is possible to accurately determine whether or not the content of the document has been changed.

  On the other hand, if the change made to the document to be printed is a change known by the print instructor, the determination in step 174 is affirmed and the process proceeds to step 178. In this case, checksum data and the like are registered in the image storage unit 42 in step 178, and the print image data to be printed is transferred to the designated printing apparatus in step 180, so that the printing process by the printing apparatus is performed. Will be done.

  Also, instead of storing the checksum as described above, the print image data (bitmap format data) itself is stored, and the presence / absence of a change is detected by comparing the print image data. ). Also in the above aspect, when the change applied to the line with the mismatched checksum is a regular change, the information that can identify the line with the mismatched checksum is printed on the printed matter. It may be.

1 is a schematic diagram of a printing system according to the present embodiment. It is a block diagram which shows schematic structure of RIP and BEP. It is a flowchart which shows the content of the change monitoring process performed by RIP. It is an image figure which shows an example of the printing result at the time of printing a change content by a character. It is an image figure which shows an example of the printing result at the time of printing a change content by a two-dimensional barcode. In the other aspect of this invention, it is a flowchart which shows the content of the checksum addition process performed by RIP. In the other aspect of this invention, it is a flowchart which shows the content of the change monitoring process performed by BEP.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Printing system 12 Image forming apparatus 16 Plate making apparatus 22 Client terminal 30 Data storage part 32 RIP processing part 42 Image storage part 44 Decompression processing part 46 Image processing part

Claims (10)

Storage means for storing information of a document that has been printed in the past;
When the printing target document instructed to be printed by the printing apparatus is a document that has been printed in the past, the data of the printing target document is compared with the information of the same document stored in the storage unit. A determination means for determining whether or not the content of the document to be printed has been changed since the past printing;
When the determination unit determines that the content of the print target document has been changed, the change unit informs that the content of the print target document has been changed or indicates change content information indicating the change content in the print target document. Change notification means to output;
A print management device. Print data described in a page description language is input as data of the document to be printed, and the printing apparatus performs printing using bitmap data obtained by expanding the print data,
The storage means stores the print data as information on the document,
2. The determination unit according to claim 1, wherein the determination unit performs the determination by comparing the input print data of the document to be printed with print data of the same document stored in the storage unit. Print management device.   The determination means adds or deletes a page of the document to be printed, changes a character itself existing in the document to be printed, changes a position or size of the character, changes the contents of the document to be printed, 3. The method according to claim 2, wherein at least one of a change in font, a change in position or thickness of a line drawing existing in the document to be printed, and a change in an application used to create the document to be printed are determined. Print management device. Print data described in a page description language is input as data of the document to be printed, and the printing apparatus performs printing using bitmap data obtained by expanding the print data,
The storage means stores the bitmap data or feature information obtained from the bitmap data as the document information,
The determination unit is configured to input bitmap data obtained by expanding the print data of the input document to be printed or feature information obtained from the bitmap data, to the bit of the same document stored in the storage unit The print management apparatus according to claim 1, wherein the determination is performed by comparing with map data or feature information obtained from the bitmap data.   5. The print management apparatus according to claim 4, wherein the determination unit performs the determination by comparing checksums calculated for the respective bitmap data to be compared as characteristic information obtained from the bitmap data.   The change notification unit presents the change contents of the print target document when the determination unit determines that the content of the print target document has been changed, and whether or not the content change of the print target document is a regular change. 2. The print management apparatus according to claim 1, wherein the information on the original to be printed is stored in the storage unit only when it is notified that the change is a regular change.   The print management apparatus according to claim 1, wherein the change notification unit performs a process of causing the printing apparatus to print the change content information together with the print target document as the process of outputting the change content information.   The change notification unit causes the change content information to be printed in a portion corresponding to a margin of a printed material on which the document to be printed is printed, or causes the change content information to be printed on the printed material in a color that is difficult to visually recognize. The print management apparatus according to claim 7.   The change notification unit stores the change content information in the storage unit every time the determination unit determines that the content of the document to be printed has been changed, and at the time of printing the change content information, The print management apparatus according to claim 7, wherein all change content information stored in the storage unit is read and printed.   As the printing device, a printer that directly prints a printing target document on a recording medium by an electrophotographic process and a plate making device that manufactures a printing plate for printing the printing target document on a recording medium by a printing machine are connected to each other. The print management apparatus according to claim 1, wherein the printer or the plate making apparatus is designated as a printing apparatus for printing an original, and printing is instructed.

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