JP2013123118A - Image processing device, image processing method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processing device capable of quickly outputting an image including an object.SOLUTION: Correlation between an output target image and a reference candidate image is determined based on an object arranged in the output target image and an object arranged in the reference candidate image, and a reference image corresponding to the output target image is determined based on the determined correlation. Then, a difference between the determined reference image and the output target image is acquired, the acquired difference is transmitted to an output device, and the output device is caused to reflect the difference in the reference image, thereby causing the output device to output the output target image.

Description

  The present invention relates to an image processing apparatus, an image processing method, and a program for outputting an image including an object.

  Variable printing is known in which a part of a plurality of objects constituting an image to be printed is replaced for each image, and a plurality of images are printed on a printing apparatus by repeatedly using an object common to the plurality of images. . In this way, in variable printing, some objects can be replaced and some objects can be used repeatedly. For example, postcards having the same contents can be printed by changing only the address.

  As a system for realizing such variable printing, there is a printing system including a client PC, a server, and a printer. In this system, master data commonly used for a plurality of images is transferred from a client PC to a server in advance and stored in a memory in the server. At the time of printing, the replacement data is transferred from the client PC to the server, and a page image including master data and replacement data is created in the server and printed on the printer. According to this printing system, the client PC does not need to transfer the master data to the server each time printing is performed, so that the data transfer amount between the client PC and the server can be suppressed.

  However, since the server transfers the image in which the object is arranged to the printer, if there is a common part in a plurality of images, the image data having the same content is transferred redundantly. Patent Document 1 describes generating a difference between an image to be printed and a reference image serving as a reference for the image to be printed, and transferring the difference. The printer that has received the difference adds the difference to the reference image stored in advance to restore the image to be printed. Thus, it is described that the amount of data transfer is suppressed by transferring the difference between two images as print data.

JP 2005-167537 A

  In the technique described in Patent Document 1, the difference between two images is transferred to the printer. However, if the contents of the two images from which the difference is acquired are greatly different, the amount of difference data increases and the difference is transferred to the printer. May increase the amount of data transferred. In this case, data transfer takes a lot of time, and the printer may not be able to quickly restore and print an image.

  In view of the above-described problems, an object of the present invention is to provide an image processing apparatus, an image processing method, and a program capable of quickly outputting an image including an object.

  An image processing apparatus according to the present invention acquires an object, creates an image in which the obtained object is arranged, an object arranged in an output target image created by the creating unit, and a reference candidate A determination unit that determines a correlation between the output target image and the reference candidate image based on an object arranged in the image; and the output target based on the correlation determined by the determination unit Determining a reference image corresponding to the image; obtaining a difference between the reference image determined by the determining unit; and the output target image; and transmitting the acquired difference to an output device; The output device includes output control means for causing the output device to output the image to be output by reflecting the difference in the reference image.

  According to the present invention, it is possible to quickly output an image including an object.

It is a block diagram which shows the structure of a variable printing system. It is a block diagram which shows the structure in a compression process part. It is a block diagram which shows the structure in an expansion | extension process part. It is a flowchart of the control part in a compression process part. It is a flowchart of the control part in an expansion | extension process part. It is an example of arrangement of objects as a result of executing variable printing. It is a flowchart which specifies the reference data in a compression process part. It is a flowchart which specifies the reference data in a compression process part. It is a block diagram which shows the structure in a compression process. It is the table | surface which showed the compression encoding method and the reference page. It is the table | surface which showed the compression encoding method and the reference page.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  The variable printing system according to the present embodiment includes a host PC, a server, and a printer. The object is transferred from the host PC to the server, and an image to be printed is generated in the server. Then, the image data is transferred from the server to the printer, and is printed by the printer based on the image data.

  FIG. 1 is a block diagram showing a configuration example of a variable printing system which is a typical embodiment of the present invention. 101 is a host computer, 102 is a variable print server, and 103 is a printer. The host computer 101 is an information processing apparatus in which a user generates a printed material for variable printing, performs printing, creates a print job including layout information, and the like. The variable print server 102 is an image processing apparatus that receives a print job corresponding to variable printing and generates variable print image data. The printer 103 is an image forming apparatus that receives generated page data and forms an image on a recording medium.

  Next, the inside of the variable print server 102 will be described. Reference numeral 104 denotes a CPU, 105 denotes a host IF control unit, 106 denotes a ROM, 107 denotes a data processing unit, 108 denotes a printer IF control unit, 109 denotes a RAM, and 110 denotes a compression processing unit. The CPU 104 controls the server by executing a program stored in the ROM 106. The ROM 106 is a readable memory that stores a program for controlling the server. The RAM 109 is a readable / writable memory used as a program execution area and a data storage area. Data processed by the data processing unit 107 and data compressed by the compression processing unit 110 are also stored in the RAM 109. The CPU 104 can execute various programs of the variable print server 102 by executing a program stored in the ROM 106 using the RAM 109 as a work memory.

  The data processing unit 107 performs data processing including processing for generating printable image data page by page by arranging objects according to layout information included in the print job. The compression processing unit 110 performs compression processing on the composite image data to be transmitted to the printer 103, and generates compressed data. The compression processing unit 110 reads the composite image data to be printed from the RAM 109 in which the composite image data generated by the data processing unit 107 is stored. Then, compression processing is performed on the read composite image data to generate compressed data, and the generated compressed data is written into the RAM 109.

  In the above compression processing, the difference between the image data to be printed and the reference data is calculated, and the difference is used as the compressed data. Details of this compression processing will be described later.

  The host IF control unit 105 communicates with the host computer 101 and receives a print job. The printer IF control unit 108 communicates with the printer 103 to transmit RAM 109 compressed data.

  Next, the inside of the printer 103 will be described. Reference numeral 111 denotes a CPU, 1112 denotes a printer IF control unit, 113 denotes a ROM, 114 denotes a data processing unit, 115 denotes a head control unit, 116 denotes a RAM, and 117 denotes an expansion processing unit. The CPU 111 controls the printer by executing a program stored in the ROM 113. The ROM 113 is a readable memory that stores a program for controlling the server. The RAM 116 is a readable / writable memory used as a program execution area and a data storage area. The received compressed data, reference data, and composite image data restored by the decompression processing unit 117 are also stored in the RAM 116. The CPU 111 performs various controls of the printer 103 by executing a program stored in the ROM 113 using the RAM 116 as a work memory.

  The decompression processing unit 117 performs decompression processing using the compressed data received from the variable print server and the reference data previously stored in the memory in the printer, and restores the composite image data.

  Note that the reference data is an image in which an object is arranged in the server, and a printed image in the printer. According to the above processing, the image generated by the server (reference data) and the image printed by the printer (reference data) are the same. Therefore, when image generation and image printing are performed in each of the server and the printer, the images are stored as reference data. Then, when performing compression in the server and expansion in the printer, reference data stored in each device is used. The reference data is stored in the ROM 106 in the printer, the memory in the compression processing unit 110, the ROM 113 in the variable print server, or the memory in the data processing unit 114.

  The data processing unit 114 performs data processing on the restored composite image data to generate print image data. The printer IF control unit 112 communicates with the variable print server 102 to receive compressed data. The head control unit 115 performs control so that print image data is printed on a recording medium.

  The variable printing job generated by the host computer 101 includes an output target object and layout information. The layout information includes arrangement information for specifying the arrangement position where each object is arranged in the output target image. Furthermore, not only the layout information which is basic information as the layout information but also image processing information for designating image processing conditions for each object to be arranged can be added to the layout information.

  The output target object includes a reusable object that is repeatedly used a plurality of times at a plurality of arrangement positions and a non-reusable object (variable object) that is used only once. The reusable object may be repeatedly used in one page, or may be repeatedly used in a plurality of pages. Further, it may be used repeatedly for a plurality of print jobs.

  In this embodiment, the variable print server repeatedly uses the reusable object, and uses the variable object to generate an image to be printed while replacing the content of the image. Therefore, for example, data that is commonly used in a plurality of pages, such as form data and master data, is used as a reuse object. On the other hand, information that needs to be replaced for each page such as an address is used as a variable object.

  In this embodiment, the host PC can store a reuse object in the server. The print job includes a variable object and layout information indicating a reuse object used in the print job. The server that receives this print job generates an image to be printed by arranging variable objects in the print job and reusable objects stored in the memory in advance according to the layout information.

  Although FIG. 1 shows an example in which the variable print server and the printer are separate apparatuses, the present invention can be similarly applied to an image forming apparatus having the function of a variable print server. The above configuration is an example of an embodiment, and any system capable of obtaining the same effect is included in the scope of the present invention.

  In this embodiment, the host PC generates a print job using PPML (Personalized Print Markup Language) which is one of data format standards for expressing variable printing. In this PPML, a page is composed of a plurality of image parts (objects). In PPML, a reuse object to be used a plurality of times can be declared. Therefore, a drawing pattern such as master data in a page that is repeatedly used is a reuse object, so that the total amount of data can be reduced. Furthermore, by holding the reuse object after RIP (Raster Image Processor) processing or after image processing such as color conversion or gradation reduction, data processing time can be reduced. However, the language used for the print job is not limited to the above PPML.

  FIG. 2 is a block diagram illustrating an internal configuration of the compression processing unit 110 in the variable print server 102 according to the present exemplary embodiment. 201 is a reference data selection unit, 202 is an inter-page differential compression encoding processing unit, 203 is an intra-page compression encoding processing unit, and 204 is a compression processing control unit. The reference data selection unit 201 specifies reference data necessary for differential compression encoding processing from a plurality of synthesized image data stored in the RAM 109 based on layout information.

  In the present embodiment, an image having a high correlation (many common parts) with the image to be printed is used as reference data in accordance with the reuse object included in the image to be printed described in the layout information. Extract. That is, when a reuse object common to two images is included in a common arrangement position in each image, it can be said that the correlation between the two images is high.

  The inter-page difference compression encoding processing unit 202 calculates the difference between the composite image data to be compressed and the reference data, acquires difference information, and generates the compressed data by using the difference information. The intra-page compression encoding processing unit 203 performs compression encoding processing within a page of the composite image data to be compressed without using reference data, and generates compressed data. The compression control unit 204 controls which compression method, the inter-page differential compression encoding processing unit 202 or the intra-page compression encoding unit, is performed according to the result of the reference data selection unit 201. For example, when the reference data is specified by the reference data selection unit 201, the inter-page differential compression encoding processing unit 202 is used, and when the reference data is not specified, the intra-page compression encoding processing unit 203 is used. To control.

  FIG. 3 is a block diagram illustrating an internal configuration of the expansion processing unit 117 in the printer 103 according to the present exemplary embodiment. Reference numeral 301 denotes an inter-page difference expansion processing unit, 302 an intra-page expansion unit, and 303 an expansion processing control unit. The inter-page difference decompression processing unit 301 restores the composite image data that was the compression target using the reference data and the compressed data. The restored composite image data that was the compression target is stored in the RAM 116. Since this composite image data may become reference data, it is retained in the RAM 116 even after printing on a recording medium unless deletion is permitted.

  The in-page decompression unit 302 decompresses the compressed data without using the reference data, and restores the composite image data that was the compression target. The restored composite image data that was the compression target is stored in the RAM 116. The decompression control unit 303 controls to use either the inter-page difference decompression processing unit 301 or the in-page decompression unit 302 as decompression processing according to the compression method specified by the compression control unit 204. Control is performed so that the inter-page differential decompression processing unit 301 is used when the inter-page differential compression encoding processing unit 202 is used, and the intra-page decompression unit 302 is used when the intra-page compression encoding processing unit is used. To do.

  Note that the server notifies the printer of information for specifying which of the inter-page differential compression or intra-page compression has been executed in the server, and in the case of inter-page differential compression, which reference data is used. The printer can refer to this information and perform decompression processing according to the compression processing in the server. This information is notified together with, for example, print data.

  FIG. 4 is a flowchart of the compression process in the variable print server 102 according to this embodiment. This process is performed in the compression processing unit 110. The processing may be executed by the CPU executing a program in the ROM.

  First, in step S401, composite image data to be compressed is designated. In S402, first layout information that is layout information of the composite image data to be compressed is obtained. In S403, second layout information that is layout information of the composite image data that is a reference candidate is obtained. The second layout information is stored in the ROM 106 of the variable print server or the memory in the compression processing unit 110 every time a print job is received, and is accumulated in the memory.

  In S404, the first layout information acquired in S402 is compared with the second layout information acquired in S403, thereby confirming the correlation between the compression target image specified in S401 and the reference candidate. Here, a value indicating a correlation between the composite image data of the reference candidate and the composite image data to be compressed is calculated. A method for calculating this value will be described later with reference to FIG.

  In S405, it is determined whether the value calculated in S404 is larger than the reference value. If the calculated value is larger than the reference value, the process proceeds to S406 assuming that the combined image data of the reference candidate has a certain level of correlation with the combined image data to be compressed. On the other hand, if the calculated value is smaller than the reference value, it is determined that the reference candidate composite image data is not highly correlated with the compression target composite image data, and the process advances to step S409. The reference value is set in advance by the CPU 104 or the like and stored in the ROM 106 or the memory in the compression processing unit 110. The reference value may be determined according to an instruction from the user, for example.

  In step S406, it is determined whether the reference candidate composite image data has higher correlation than the reference candidate composite image data that has been determined to have high correlation. This determination is performed by storing the value calculated in S405 in the ROM 106 or the like in S407 described later and comparing it with the calculated value.

  When it is determined that the correlation is higher than the reference candidates so far, the process proceeds to S407, and when it is determined that the correlation is not high, the process proceeds to S409.

  In S407, the composite image data name is registered or updated as a reference data name. In S408, the reference data specifying flag is set to 1 to indicate that the reference data has been specified even once. On the other hand, in S409, the reference data name registered so far is held. If the reference data name has never been registered, the reference data cannot be specified, and the reference data specifying flag becomes 0. This flag is set in the ROM 106, the memory in the compression processing unit 110, or the like.

  In S410, it is determined whether there are other reference candidate composite image data. If there are other candidates, the process proceeds to S403, and the processes of S403 to S409 are repeated for the remaining combined image data until there are no more candidates. If there is no other candidate, it is determined that the reference data having the highest correlation with the image data to be compressed has been specified, and the process proceeds to S411.

  In S411, it is determined by the above reference data specifying flag whether the reference data has been specified. If the reference data specifying flag is 1, it is determined that the reference data can be specified, and the process advances to step S412 to perform the inter-page differential compression encoding process. On the other hand, if the reference data specifying flag is 0, it is determined that the reference data has not been specified, and the process proceeds to S415 in order to perform the intra-page compression encoding process.

  In step S412, the composite image data to be compressed is read from the RAM 109. In step S413, the composite image data that is the specified reference data is read from the RAM 109. In S414, by calculating the difference between the compressed data and the reference data, the inter-page differential compression encoding process is performed to generate the compressed data.

  On the other hand, in S415, the composite image data to be compressed is read from the RAM 109 as in S412. In step S416, compression encoding processing is performed on the composite image data to be compressed within the page to generate compressed data.

  In S417, the compressed data generated in S414 or S416 is written into the RAM 109. At this time, the compression method performed on the print data in the server and the specific information for specifying the reference data when the difference between pages is taken are written.

  The above is the processing flow in the compression processing. Note that the data written in the RAM 109 in S417 is read by the printer IF control unit 108 and transferred to the printer 103. The printer IF control unit performs output control for outputting compressed data (difference), whereby an image is printed on the printer. The printer output process will be described with reference to FIG.

  FIG. 7 is a flowchart showing an example of calculation processing for extracting reference data in S404 of FIG. The processing content of S404 described above will be specifically described with reference to the flowchart of FIG.

  First, in S701, a reuse object name arranged in an image to be compressed is extracted from the first layout information acquired in S402. In step S702, the second layout information acquired in step S403 is searched for the reuse object name extracted in step S701. If there is the same reuse object name, the process proceeds to the reuse object S703 common to the image to be compressed and the reference candidate. On the other hand, when there is no same reuse object name, S404 is ended as it is.

  In step S <b> 703, it is determined in steps S <b> 701 and S <b> 702 whether the reuse objects common to the compression target image and the reference candidate are in the same arrangement or in the same arrangement order in the two images. In the case of the same arrangement and the same arrangement order, since it can be determined that the image areas of the corresponding reuse object have the same pixel value, the process proceeds to S704. If it is not the same arrangement or the same arrangement order, S404 is terminated as it is.

  In S704, the area of a region where a reuse object common to the reference candidate image is arranged in the image to be compressed is calculated, and S404 ends. Note that the reuse object is common to the compression target image and the reference candidate image, and is arranged in the same region in the two images.

  In the process of S405 to 410 in FIG. 4 described above, the candidate having the largest area in the compression target image of the reuse object common to the compression target image is specified among the reference candidate images. In the above example, the area in the compressed image is obtained. However, the area ratio of the reuse object to the compressed image may be obtained, and in S405 to S410, reference data may be specified from the reference candidates according to the area ratio. . In this way, the reference data is specified from the layout information.

  FIG. 5 is a flowchart of the decompression process in the printer 103 according to this embodiment. This process may be executed by the decompression processing unit 117, or may be realized by the CPU 111 executing a program stored in the ROM 113.

  First, in S500, the compressed data, the compression method performed on the print data in the server, and the specific information for specifying the reference data when the inter-page difference is taken are received from the variable print server 102.

  In S501, based on the specific information received in S500, it is determined whether the compression method performed in the variable print server 102 is the inter-page differential compression encoding process. If it is the inter-page difference compression encoding process, the process proceeds to S502, and the inter-page difference expansion process is performed. On the other hand, if it is not the inter-page differential compression encoding process, the process proceeds to S505, and the in-page expansion process is performed.

  In S502, the compressed data received in S500 is read from the RAM 116. This compressed data is the difference between the compressed image and the reference image calculated by the server in S414. In S503, the reference data specified by the specific information received in S500 is read from the RAM 116. This reference data is data output by the printer itself (output device itself). In S504, the compressed image data (difference) read in S502 is reflected in the reference data read in S503, thereby restoring the composite image data that was the compression target.

  On the other hand, in S505, the compressed data is read from the RAM 116 as in S502. In step S506, decompression processing is performed on the compressed data to restore the composite image data that was the compression target. Then, the composite image data that was the compression target restored in S507 is written into the RAM 116. The above is the processing flow in the decompression process.

  FIG. 6 is an arrangement example of objects as a result of executing variable printing in the present embodiment. In the present embodiment, an example is shown in which the number of customers is three and the total number of printed pages is nine. Reference numerals 601 to 609 are print pages composed of pages 1 to 9, 641 to 643 are variable objects indicating customer names, and 651 to 659 are reuse objects.

  In the example of FIG. 6, the customer 641 has a total of 3 pages 601 to 603, the customer 642 has a total of 4 pages 604 to 607, and the customer 643 has a total of 2 pages 608 to 609. It is. Object 651 is used on all pages, and object 652 and object 658 are used on the first and last pages of all customer pages. The objects 653 to 657 and the object 659 are replaced or added according to the information of the customers 641 to 643, and the pages to be used vary depending on the customers. For example, “luxury car D” of the object 656 is used for page 3 which is the third page of the customer 641 and page 9 which is the second page of the customer 643, but is not used by the customer 642. In this way, the use of objects changes according to customer information, and the number of pages also changes. Note that the reuse object used in each page is specified in the layout information included in the print job.

  FIG. 10 is a table showing the relationship between the compression encoding method and the reference page when the compression processing is performed in this embodiment. This table is created by the server through the processing in S403 to S410 of FIG.

  The table in FIG. 10 shows whether the compression encoding method uses the intra-page compression encoding process or the inter-page differential compression encoding process when the compression process is performed on the print page in FIG. Which page was listed on each page. As an example, page 1, page 2, page 8, and page 9 will be described. Since page 1 is the first page, there is no reference page, so intra-page compression encoding processing is performed and it becomes a reference page candidate. Page 2 does not become a reference page because page 1 has the same image area as page 2, and therefore is subjected to intra-page compression encoding processing and becomes a reference page candidate. For page 8, page 1 having the same area as page 8 among pages 1 to 7 that are reference page candidates becomes a reference page, and inter-page differential compression encoding processing is performed to become a reference page candidate. For page 9, page 3 having the same area as page 9 among pages 1 to 8 which are candidates for the reference page becomes a reference page, and inter-page differential compression encoding processing is performed. As described above, when a print page is transferred, the reference page is specified to reduce the data transfer amount of the print page.

  According to the above embodiment, by specifying the image to be referred to for each page to be printed based on the variable printing layout information, and obtaining the difference between the page to be printed and the reference image, the inter-page difference is obtained. Perform compression encoding processing. Specifically, whether a reusable object common to two pages, a page to be printed and a reference page, is specified by layout information, and a difference from the reference page is calculated according to the reusable object. judge. In particular, in the present embodiment, the above determination is performed based on the area of the reuse object in the page to be printed.

  Thus, the inter-page compression process can be realized by taking the difference from the reference page that has many parts common to the page to be printed (highly correlated). As a result, the amount of difference data decreases, and the amount of data transferred from the server to the printer decreases. Therefore, it is possible to quickly print an image including an object.

  Also, if there is no common object in multiple images, or even if there is a common object, if the placement position is different, the difference between the images is not calculated and output, and the output target image is output. ing. Thereby, it is possible to prevent the calculation of the difference and the restoration of the image from being executed even though the difference between the images is large and the reduction in the amount of transferred data cannot be expected.

  In the above embodiment, the correlation between images is determined based on the area of the object. However, various types of information for specifying an image with a small difference from the output target image can be used. . For example, the type of object included in the image and the content of the image processing specified for the object can be used.

  For example, in the case of a background object, even if the area is large, another object may be combined with the object. In that case, even if there is an image having a background object common to the output target image, the difference between the images may become large if the object combined with the background is greatly different.

  Therefore, it may be determined whether or not an object common to the two images is the background. If the object is the background, the priority of the image including the background to be the reference image may be lowered. For example, the background object may be excluded from the conditions for determining the reference image. The determination of the object type may be performed based on the information received from the client PC, for example, based on the information received from the client PC.

  Furthermore, the reference image may be determined according to the content of the image processing specified for the object in the layout information. When the objects are combined as described above, the difference between the two images may increase even if the area of the background object is large. Therefore, when composition is designated for an object, the priority for making it a reference image may be lowered. For example, the composition process is designated, and the background object may be excluded from the conditions for determining the reference image.

  Further, the variable print server may determine the overlap of objects based on the layout information. The layout information describes the arrangement position of the object, and the overlapping of the objects can be determined by considering the arrangement position and the size of the object. When the overlap of the objects can be confirmed by this determination, an object that overlaps another object may be excluded from the reference image determination process. Alternatively, when the overlap of the objects can be confirmed, an object that is an upper layer and other objects do not overlap may be included in the reference image determination process.

  In the first embodiment, as an example of determining the correlation between the print target page and the reference candidate page, the correlation is determined based on the area of the reuse object common to the two pages. In this embodiment, as another example of the above-described determination, the determination is performed based on the number of reuse objects common to two pages. The variable printing system configuration, the compression / decompression processing unit, the compression / decompression process flowchart, and the example of the object layout as a result of executing variable printing are shown in FIGS. 1, 2, 3, 4, and 4 of the first embodiment. 5. Same as FIG. Therefore, only the difference in the flowchart of the calculation process for extracting the reference data will be described.

  FIG. 8 is a flowchart illustrating an example of calculation processing for extracting reference data in S404 of FIG. The processing content of S404 will be specifically described with reference to the flowchart of FIG. In addition, about the process of S801-SS803, since it is the same as the process of S701-S703 demonstrated in FIG. 7, description is abbreviate | omitted.

  In S804, the number of reuse objects extracted in S801 to S803 is calculated. Note that the reuse object is common to the compression target image and the reference candidate image, and is arranged in the same region in the two images.

  In the process of S405 to 410 in FIG. 4 described above, the candidate having the largest number of reuse objects in common with the compression target image is identified from the reference candidate images. In the above example, the number of reuse objects is obtained, but the total number of objects included in the compressed image or the ratio of the total number of objects included in the compressed image and the reference image may be obtained. In S405 to S410, reference data is specified from the reference candidates according to the ratio.

  When variable printing is performed in which the arrangement size of the reuse object is used at a fixed size, the method of specifying the reference data based on the number of reuse objects is the reference page rather than the method of using the area. The calculation method for specifying is simple. Therefore, it does not take time to calculate.

  In this embodiment, a process for holding and deleting composite image data that is a candidate for reference data will be described. The description of the parts common to the above embodiments is omitted.

  FIG. 9 is a block diagram illustrating an internal configuration of the compression processing unit 110 in the variable print server 102 according to the present exemplary embodiment. The difference from FIG. 2 is that there is a data deletion control unit 901 that selects composite image data to be deleted from among a plurality of composite image data and instructs deletion. Therefore, only the difference will be described.

  The data deletion control unit 901 selects the composite image data to be deleted from the reference data candidates among the plurality of composite image data that are reference data candidates, and instructs the CPU 104 and the CPU 111 to delete the selected composite image data. Put out. Then, the CPU 104 deletes the selected composite image data from the memory (ROM 106, RAM 109, etc.) storing a plurality of composite image data. Further, along with this deletion, the reference data selection unit 201 deletes the reference data candidate. When the reference data selection unit 201 reads the reference data using, for example, a table for specifying the reference data, the specific information for specifying the reference data to be deleted is deleted from this table. Then, since the reference data can be overwritten in the memory, it can be said that the reference image is deleted by deleting the specific information.

  At this time, specification information for specifying reference data to be deleted is transmitted from the server to the printer. Then, the CPU 111 in the printer 103 deletes the composite image data specified by the specific information from the memory (ROM 113 or RAM 116) in which a plurality of restored composite image data is stored. In this way, the composite image data that is no longer a candidate for reference data for performing the inter-page differential compression encoding process is deleted.

  In the present embodiment, the configuration and the method for instructing to select and delete the composite image data to be deleted from the stored composite image data have been described. However, the composite image data to be stored is instructed. It may be a simple configuration and method.

  Further, the reference data stored in the memory of each of the server and the printer is not limited in its storage format. For example, the data may be compressed and stored using an in-page compression encoding processing unit, or may be stored without being compressed. A method of selecting and storing which composite image data is to be compressed may be used depending on the capacity that can be stored in the RAM and the processing time for decompressing the compressed composite image data.

  Further, the criterion for selecting the composite image data to be deleted from the reference data candidates is not particularly limited in this embodiment. For example, if the capacity of the RAM that stores the composite image data that is the reference data candidate is insufficient, the composite image data that is generated in the future may be deleted from the reference data candidate. Alternatively, a method may be used in which composite image data that is used as reference data is retained and deleted from the composite image data that is used less frequently.

  Further, although the storage device storing a plurality of composite image data has been described as the RAM, it is not limited to this. For example, a dedicated buffer for storing the reference page may be provided.

  In addition, an instruction to delete the composite image data may be issued by a dedicated control circuit which has issued an instruction to delete the composite image data by the CPU.

  In this way, in addition to being able to perform the optimum compression encoding process for each page, it is possible to reduce the composite image data that is a candidate for reference data and to secure a free memory capacity.

  According to the above embodiment, by specifying the image to be referred to for each page to be printed based on the variable printing layout information, and obtaining the difference between the page to be printed and the reference image, the inter-page difference is obtained. Perform compression encoding processing. Specifically, whether a reusable object common to two pages, a page to be printed and a reference page, is specified by layout information, and a difference from the reference page is calculated according to the reusable object. judge.

  Thus, the inter-page compression process can be realized by taking the difference from the reference page that has many parts common to the page to be printed (highly correlated). As a result, the amount of difference data decreases, and the amount of data transferred from the server to the printer decreases. Therefore, it is possible to quickly print an image including an object.

  In the above embodiment, the reference data is specified by the area or the number of reuse objects. However, the area and the number may be combined, or the reference data may be specified by a condition other than the area and the number. May be. That is, as long as the reference data having high correlation with the output target image is specified based on the output target image and the reuse object common to the reference data, the specifying method is not limited.

  In the above embodiment, the intra-page compression encoding process is described as the process of compressing within the page of the composite image data, but the specific method is not particularly limited. For example, it may be run-length encoding that encodes a length in which the same color continues, or Huffman encoding that encodes according to the number of times the same color occurs. In the present invention, the specific compression method is not limited as long as it is a compression algorithm that can compress data within the same page without using reference data different from the composite image data to be compressed.

  Furthermore, in the above embodiment, the inter-page differential compression encoding process is described as a process of generating compressed data using difference information, but the specific method is not particularly limited. For example, difference information obtained by calculating a difference between composite image data to be compressed and reference data may be used as compressed data, or compression coding processing may be performed on the difference information. Further, the difference information is described as information obtained by calculating the difference between the composite image data to be compressed and the reference data, but is not limited thereto. Information obtained by calculating a difference from the composite image data to be compressed and the layout information may be used. For example, by looking at the layout information of the composite image data to be compressed and the reference data, it is possible to know which pixels are the same reuse object, so that difference information can be generated based on that information. That is, the specific compression method is not limited as long as it is a method for performing differential compression using reference data having high correlation with the composite image data to be compressed.

  Further, when image processing is performed on one of the images to be compressed and the common reuse object in the reference data candidate, it may be determined as a common object or a different object. You may determine as. Even if the object names are different, if the contents of the objects are similar, they may be determined as a common object.

  For example, in FIG. 6, a case where the difference between “ordinary car A” of the object 653 on page 1 and “ordinary car C” on the object 655 on page 2 is only the color of the vehicle body. Since these two objects have the same background image, which is an image other than the vehicle body, and the vehicle body images are different in color and have the same contour information, it can be determined that the two objects have high correlation. Therefore, the inter-page differential compression encoding process can be performed by setting the reference page of page 2 to page 1 as shown in FIG.

  Similarly, if the background images of the “ordinary car B” of the object 654 and the “luxury car D” of the object 656 are the same, it can be determined that the correlation is high because the background images are the same although the vehicle bodies are different. Similar to page 2, the inter-page differential compression encoding process can be performed.

  In order to determine whether or not different objects have a correlation from the layout information, for example, attribute information that can indicate the correlation may be simply added to each object. For example, it can be determined by using attribute A if the color is simply different, and attribute B if only the background is the same. In the case of a human image, skin color correction may be performed according to customer information even for the same object. Even in such a case, if it is known from the layout information what kind of skin color correction is applied, it can be determined whether the person image has high correlation.

  In the above embodiment, an example in which reuse objects with high correlation are arranged at the same pixel position between pages has been described. However, even if reusable objects of the same size are arranged at different pixel positions, the pixel position of the reference data can be analyzed from the layout information. Therefore, the inter-page differential compression encoding process may be performed using that information.

  Further, the data processing of the variable print server 102 and the printer 103 includes processes such as a color conversion process for converting to a device color space and a low gradation process for converting to printable data in addition to the above-described processes. . In this embodiment, which processing is included in which data processing unit is not limited.

  Further, in the above-described embodiment, the example in which the compression processing unit 110 and the decompression processing unit 117 handle the compression processing and the decompression processing has been described. However, a code obtained by programming a part or all of the processing contents of the compression processing unit 110 and the expansion processing unit 117 so as to obtain the same effect is stored in the ROM 106 or the ROM 113 and executed by the CPU 104 or the CPU. It may be. Similarly, a code obtained by programming part or all of the processing contents of the data processing unit 107 and the data processing unit 114 may be stored in the ROM 106 or the ROM 113 and executed by the CPU 104 or the CPU.

  The printer in the above embodiment may be an ink jet printer using ink, a laser printer using toner, or a copying machine.

  In the above-described embodiments, a printer that prints an image is described as an example of an apparatus that outputs an image. However, the present invention is not limited to this. For example, the display target image may be transferred from the server to the display device that displays the image, and the image may be displayed on the display device.

  The above embodiment can also be realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiments is supplied to a system or apparatus via a network or various storage media, and a computer (or CPU, MPU, etc.) of the system or apparatus reads the program. It is a process to be executed. For example, a method of storing a code obtained by programming a part or all of the processing contents in the ROM and executing it by the CPU may be used. In addition, the above program may be executed by one computer (CPU or MPU), or may be executed by a plurality of computers cooperating.

101 Host computer 102 Variable print server 103 Printer 104 CPU
105 Host IF control unit 106 ROM
107 Data Processing Unit 108 Printer IF Control Unit 109 RAM
110 Compression processing unit

Claims (12)

Creation means for obtaining an object and creating an image in which the obtained object is arranged;
The correlation between the output target image and the reference candidate image is determined based on the object arranged in the output target image created by the creating unit and the object arranged in the reference candidate image. Determination means to perform,
Determining means for determining a reference image corresponding to the image to be output based on the correlation determined by the determining means;
The difference between the reference image determined by the determination unit and the output target image is acquired, the acquired difference is transmitted to the output device, and the output device reflects the difference in the reference image. Output control means for causing the output device to output the image to be output;
An image processing apparatus comprising:   The creation means can arrange the objects in a plurality of images by repeatedly using the objects stored in the memory, and the determination means can be used for the plurality of images in the memory. The image processing apparatus according to claim 1, wherein the correlation between the plurality of images is determined based on a stored object.   The determination unit determines the correlation between the output target image and the reference candidate image based on the output target image, the object arranged in the reference candidate image, and the arrangement position where the object is arranged. The image processing apparatus according to claim 1, wherein:   The creation means acquires layout information for specifying an object and a placement position where the object is placed in the image created by the creation means, and the determination means is arranged at the placement position specified by the layout information. The image processing apparatus according to claim 1, wherein a correlation between the output target image and the reference candidate image is determined based on the image.   The layout information is information for specifying an arrangement position of an object in the image created by the creation unit and an object arranged in the image, and the determination unit includes an object identified by the layout information The image processing apparatus according to claim 4, wherein a correlation between the output target image and the reference candidate image is determined based on an arrangement position of the object.   The determination unit is configured to output the output target image and the reference candidate image based on at least one of an area of the object arranged in the image created by the creating unit and the number of objects arranged in the image. The image processing apparatus according to claim 1, wherein the correlation is determined.   The output device reflects the difference transmitted by the output control unit on the image corresponding to the reference image determined by the determination unit among the images output by the output device itself. The image processing apparatus according to claim 1, wherein an image is created, and the created image to be output is output.   The output control means transmits the difference and specific information for specifying the reference image determined by the determining means to the output device, and the output device adds the reference information specified by the specific information to the reference image. The image processing apparatus according to claim 7, wherein the output target image is created by reflecting the difference in a corresponding image.   The determining means determines whether to determine a reference image corresponding to the output target image based on the correlation between the output target image and the reference candidate image, and when determining to determine a reference image, The image processing apparatus according to claim 1, wherein a reference image is determined from the reference candidate images.   When the determining unit determines not to determine the reference image, the output control unit transmits the output target image to the output device without acquiring a difference between the output target image and the reference image. The image processing apparatus according to claim 1, wherein the image to be output is output. Get the object, create an image with the acquired object,
Based on the object arranged in the created output target image and the object arranged in the reference candidate image, the correlation between the output target image and the reference candidate image is determined,
Based on the determined correlation, determine a reference image corresponding to the output target image,
By obtaining the difference between the determined reference image and the output target image, transmitting the obtained difference to the output device, and reflecting the difference on the reference image on the output device, An image processing method comprising causing the output device to output an image to be output.   A program for causing a computer to execute the image processing method according to claim 11.

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