JP2013097407A - Image processing apparatus and printing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a more inexpensive configuration and to implement fast print processing, in an image processing apparatus which outputs image data for print processing.SOLUTION: In an image processing apparatus, image data is subjected to compression processing per block, which is composed in units of one or more bytes to generate compressed image data, and the compressed image data is subjected to decompression processing per block, and image data subjected to the decompression processing is outputted. The image data is subjected to the compression processing after dummy pixel data is arranged before pixel data in a head position so that the pixel data in the head position including one piece of bit data, out of pixel data arranged in an array direction of bit data is printed in a desired position of a print sheet.

Description

  The present invention relates to an image processing apparatus and a printing system using the image processing apparatus, and more particularly to a compression process performed on image data to be printed.

  Conventionally, various printing systems that perform printing processing based on image data created by a computer application or image data obtained by photoelectrically reading an original image by a scanner or the like have been proposed.

  In such a printing system, after performing compression processing such as run length compression on image data, a printer control code described in PDL (Page Description Language) is generated based on the compressed image data, The printer control code is temporarily stored on the hard disk. Then, the stored printer control code is read from the hard disk and developed, and the developed image data is temporarily stored in the memory, and then output to the print engine for printing.

  Here, the image data is obtained by arranging a large number of pixel data in a two-dimensional manner, and each pixel data is generally composed of 3-bit or 4-bit bit data.

  On the other hand, a CPU (Central Processing Unit) that performs the above-described compression processing and decompression processing is generally configured to perform compression processing and decompression processing in units of bytes for the convenience of hardware design. Many (see, for example, Patent Document 1).

  Therefore, when each pixel data is composed of, for example, 3-bit bit data, if the 3-bit bit data straddles between byte units that are processing units of compression processing, the expansion processing is performed in byte units. When writing bit data into the memory, it is necessary to perform a bit shift, which requires complicated processing, which slows down the expansion process and delays the start timing of the printing process. I can't do it.

Japanese Patent Laid-Open No. 7-262082 JP 63-304293 A

  Therefore, when each pixel data is composed of, for example, 3-bit bit data, 3 bytes (in order to prevent the 3-bit bit data from crossing between byte units as processing units of compression processing) (24 bits) pixel data, that is, eight pixel data is set as one block unit (processing unit), and compression processing and decompression processing are performed in units of this block.

  Here, the case where compression processing and decompression processing are performed in units of blocks as described above will be described in detail with reference to FIG. FIG. 14 shows original image data to be printed, pixel data to be compressed generated from the original image data, a printer control code generated from the compressed image data, and a printer control code. The image data that has been subjected to the expansion process and the image data for printing composed of the image data that has been subjected to the expansion process are sequentially shown from the top.

  First, after the original image data as shown in FIG. 14 is subjected to a cutting process according to the paper size of the printing paper as required, generally the data capacity after the compression process is reduced. Therefore, from the pixel data of one row, the pixel data from the head position (5, 3) including 1 bit data to the pixel data of the rear end (14, 3) including 1 bit data are pixels to be compressed. Cut out as data.

  Then, in order to perform compression processing on the extracted pixel data in units of blocks, dummy pixel data of 6 pixels (zero pixel data) is arranged behind the pixel data at the rear end as shown in FIG. The

  Next, compression processing is performed on the pixel data in which dummy pixel data is arranged as described above, and an image code is generated based on the compressed image data, and a printer control code as shown in FIG. 14 is generated. . Note that the coordinate code in the printer control code shown in FIG. 14 indicates the coordinate value in the original image data of the pixel data at the head position described above.

  Then, a development process is performed on the printer control code generated as described above, and image data for printing is generated based on the developed image data. At this time, the developed image is processed. If the data is used as image data for printing as it is, the pixel data at the position of the coordinate value (5, 3) in the original image data is the position of the coordinate value (0, 3) in the coordinate system of the printing paper. Therefore, a shift of 5 pixels (5 dots) occurs.

  Therefore, in order to print the pixel data at the position of the coordinate value (5, 3) in the original image data at the position (5, 3) in the coordinate system of the printing paper, as shown in FIG. Based on the coordinate values (5, 3) included in the data, it is necessary to perform a bit shift process on the pixel data of one row.

  However, in order to perform such bit shift processing, it is necessary to provide a barrel shifter as disclosed in Patent Document 2, for example, and using such a special circuit increases the development man-hours and costs. There is.

  Also, if the bit shift process as described above is performed at the time of the expansion process, it takes time for the bit shift process. Therefore, when performing a high-speed print process, the print speed cannot be kept up. In spite of being in a state in which printing is possible, there is a problem that generation of image data for printing has not been completed, and it is difficult to realize high-speed printing processing.

  SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide an image processing apparatus and a printing system that can be manufactured at a lower cost and can realize a high-speed printing process.

  An image processing apparatus according to the present invention includes: an image data acquisition unit that acquires image data that is image data to be printed on a printing paper and that includes a plurality of pixel data represented by a plurality of bit data; A compression processing unit that performs compression processing on the image data acquired by the unit in units of blocks including one or more byte units divided by pixel data boundaries in the arrangement direction of the bit data, and generates compressed image data A decompression processing unit that performs decompression processing on the compressed image data generated by the compression processing unit in units of blocks and outputs the image data subjected to the decompression processing. The top of the pixel data arranged in the arrangement direction so that the pixel data at the top position including one bit data is printed at a desired position on the printing paper. After placing the dummy pixel data prior to the location of the pixel data, it is characterized in that those subjected to compression processing.

  In the image processing apparatus of the present invention, the compression processing unit is arranged in front of the pixel data at the head position so that the pixel data at the head position is arranged at the original position of the image data before the compression processing after the decompression process. Dummy pixel data can be arranged.

  Further, the image data acquisition unit acquires a plurality of image data, and receives an imposition print instruction for arranging and printing the plurality of image data acquired by the image data acquisition unit on one print sheet. An imposition printing instruction receiving unit is provided, and when the imposition processing instruction is received by the imposition printing instruction receiving unit, the uncompressing processing unit applies to the compressed image data arranged adjacent to the bit data arrangement direction. When the decompression process is performed, the decompressed image data of the first or rear end block of one compressed image data and the decompressed image data of the other compressed image data block adjacent to the first or rear end block are processed. Are adjacent to the block at the head or rear end of one compressed image data and the block at the head or rear end of the other compressed image data. It can be made to perform a predetermined operation on the image data of the expansion processed block.

  Further, an OR operation can be used as the predetermined operation.

  In addition, the compression processing unit can separately compress the plurality of image data to generate a plurality of compressed image data.

  Further, the expansion processing unit can individually perform the expansion processing on the plurality of compressed image data, and sequentially output the plurality of image data subjected to the expansion processing based on the imposition printing instruction.

  In addition, it is possible to provide a print control code generation unit that collectively generates compressed print data and additional information data representing predetermined information added to the image data as a print control code.

  The printing system according to the present invention photoelectrically reads a document image and a printing apparatus including a printing unit that performs printing processing on printing paper based on the image processing apparatus and image data output from the image processing apparatus. And a document reading device that outputs the image data to the image processing device.

  A printing system according to the present invention is provided on a printing paper based on a computer including an image data acquisition unit and a compression processing unit in the image processing apparatus, a decompression processing unit in the image processing apparatus, and image data output from the decompression processing unit. And a printing apparatus having a printing unit that performs a printing process.

  According to the image processing apparatus of the present invention, compression processing is performed on the image data in units of blocks consisting of one or a plurality of bytes to generate compressed image data, and the compression processing is performed on the compressed image data in units of blocks. In the image processing apparatus that outputs the developed image data, the pixel data at the head position including one bit data of the pixel data arranged in the arrangement direction of the bit data is desired on the printing paper. Since the dummy pixel data is arranged before the pixel data at the head position so as to be printed at the position of the image data, the compression process is performed. Therefore, the image data subjected to the decompression process in units of blocks is described above. Since there is no need to perform such bit shift processing, it is possible to achieve an inexpensive configuration that does not require a circuit that performs bit shift processing, and high-speed printing processing. It can be realized.

  According to the present invention, it takes time to arrange dummy pixel data before compression processing. For example, when printing image data read by a scanner, the reading time of an original image by the scanner is set. Since a considerable time is required until the compression processing is completed, the processing time for arranging the dummy pixel data is not so much of a problem.

  On the other hand, when the bit shift process is performed after the expansion process as described above, since it directly affects the start timing of the print process, it is difficult to realize a high-speed print process.

1 is a block diagram showing a schematic configuration of a printer system using an embodiment of an image processing apparatus of the present invention. Schematic diagram for explaining the operation of a printer system using an embodiment of an image processing apparatus of the present invention. Diagram showing an example of printer control code 6 is a flowchart for explaining the operation of a printer system using an embodiment of an image processing apparatus of the present invention. Schematic diagram for explaining the effect of imposition printing of a printer system using an embodiment of the image processing apparatus of the present invention The figure for demonstrating other embodiment of the compression process in 2 side up printing Diagram showing an example of 4-sided printing The figure for demonstrating the compression process and expansion | deployment process at the time of 4-sided up printing, and a printer control code The figure which shows the other example of 4 side up printing The figure which shows the printer control code which contains the character image code as additional information The figure which shows an example at the time of expanding and printing the printer control code shown in FIG. The figure which shows the example which printed the number of pages in the white square The figure which shows the printer control code which contains a white image code and a character image code as additional information The figure for demonstrating the example in the case of performing a bit shift process after expanding a printer control code

  Hereinafter, a printer system using an embodiment of an image processing apparatus of the present invention will be described in detail with reference to the drawings. FIG. 1 is an overall schematic configuration diagram of a printer system according to the present embodiment.

  As shown in FIG. 1, the printer system of this embodiment includes a scanner 10, a printer 20, and a computer 30.

  The scanner 10 photoelectrically reads a document sheet on which a document image is printed, acquires image data, and outputs the image data to the printer 20.

  Here, the image data output from the scanner 10 in this embodiment is bitmap data in which a large number of pixel data are arranged in a two-dimensional manner as shown in FIG. 2 shows original image data to be printed, pixel data to be compressed generated from the original image data, a printer control code generated from the compressed image data, and a printer control code. The image data that has been subjected to the expansion process and the image data for printing composed of the image data that has been subjected to the expansion process are sequentially shown from the top.

  In this embodiment, each pixel data constituting the image data is represented by 3-bit bit data as shown in FIG. Note that the bit data shown in FIG. 2 is obtained by extracting pixel data of a predetermined row in the image data. In the present embodiment, 3-bit bit data is used as each pixel data. However, the present invention is not limited to this. For example, 4-bit or more bit data may be used.

  As shown in FIG. 1, the printer 20 includes a control unit 21, a memory 22, a hard disk 23, a print engine 24, an ink head 25, and a print instruction receiving unit 26. The control unit 21 further includes an image data acquisition unit 40, a compression processing unit 41, a printer control code generation unit 42, and a decompression processing unit 43.

  The image data acquisition unit 40 acquires the image data output from the scanner 10, outputs the image data to the memory 22, stores it, acquires a printer control code described later output from the computer 30, and acquires the printer The control code is output to the hard disk 23 and stored.

  The compression processing unit 41 performs compression processing on the image data read from the memory 22. Specifically, the compression processing unit 41 of the present embodiment performs a run-length compression process on the input image data in the arrangement direction of the bit data constituting each pixel data.

  Here, the control unit 21 including the compression processing unit 41 is configured by hardware such as a CPU (Central Processing Unit), and is configured to perform processing in units of bytes for convenience of hardware design. ing.

  Therefore, the compression processing unit 41 also performs compression processing in units of one or a plurality of bytes. At this time, when each pixel data is composed of 3-bit bit data as in this embodiment, as described above, Therefore, it is necessary to prevent the 3-bit bit data from straddling between the processing units of the compression processing. That is, it is necessary that the processing unit of the compression process is divided at the boundary of the pixel data.

  Therefore, in the compression processing unit 41 of this embodiment, 3-byte pixel data, that is, eight pixel data is set as one block unit (processing unit), and run-length compression is performed in this block unit.

  On the other hand, when run length compression is performed, in order to reduce the capacity of the compressed data, generally one bit data of one row of pixel data is included as shown in FIG. From the pixel data at the head position to the rear end pixel data including 1 bit data is cut out as pixel data to be compressed. In the present embodiment, it is assumed that compression processing is performed from the left to the right of the bit data shown in FIG.

  However, at this time, if the compression processing is started in block units from the pixel data at the head position cut out as described above, after the expansion processing is performed as described above, the pixel data is shifted to the pixel data after the expansion processing. It is necessary to perform processing, and it takes a lot of processing time.

  Therefore, in the present embodiment, dummy pixel data is arranged before the pixel data at the head position as shown in FIG. 2 so that the pixel data at the head position is arranged at a desired position after the expansion process, Thereafter, compression processing is performed. More specifically, in this embodiment, the dummy pixel data is arranged so that the pixel data at the head position is arranged at the original position of the image data after the decompression process and before the compression process. At this time, if the number of pixel data to be compressed including dummy pixel data is not a block unit, dummy pixel data is arranged after the rear end pixel data including 1 bit data as shown in FIG. To do.

  Then, the compression processing unit 41 sends the coordinate value of the leading dummy pixel data for each row of the image data to the printer control code generation unit 42 together with the compressed image data subjected to the compression processing after the dummy pixel data is arranged as described above. Output.

  The printer control code generation unit 42 generates a printer control code as shown in FIGS. 2 and 3 based on the compressed image data output from the compression processing unit 41 and the coordinate values of the leading dummy pixel data for each row. Is.

  FIG. 3 shows the printer control code shown in FIG. 2 in more detail. The printer control code generated in the present embodiment is composed of a coordinate code, an image code, a page break code, and the like as shown in FIG. The coordinate code includes the coordinate value (x, y) of the head dummy image data for each row described above. The image code includes size information of compressed image data and image data after decompression processing, information on colors (for example, CMYK) included in the image data, information on presence / absence of compression processing, and information on an arithmetic method at the time of decompression processing And compressed image data. Note that information on the calculation method in the expansion process will be described in detail later.

  The printer control code generated by the printer control code generation unit 42 is output to the hard disk 23 and stored.

  The decompression processing unit 43 reads the printer control code stored in the hard disk 23, performs decompression processing on the compressed image data included in the printer control code in units of blocks, and includes dummy pixel data as shown in FIG. Image data is generated. The image data after the expansion process is temporarily stored in the memory 22 based on the coordinate code included in the printer control code, and then output to the print engine 24.

  The print engine 24 controls the drive of the ink head 25 by outputting a control signal to an ink head 25 described later based on the input image data.

  The ink head 25 is provided in a non-contact state above the conveyance surface of the printing paper, and includes a line head that selectively ejects ink toward the printing paper. For example, when forming a full-color image, it is composed of four color line heads of K (black), C (cyan), M (magenta), and Y (yellow).

  The print instruction receiving unit 26 includes input receiving means such as a touch panel, for example, and receives input by an operator such as various printing conditions and output methods such as the number of printed sheets, the number of printed copies, and imposition printing instructions. .

  As shown in FIG. 1, the computer 30 includes an application 31 and a printer driver 32. Note that the application 31 and the printer driver 32 are configured by programs installed in the computer 30.

  The application 31 is a program that can edit image data representing a document image, such as a memo pad or Word (registered trademark), and the image data edited in the application 31 is output to the printer driver 32.

  The printer driver 32 has a user interface that accepts input by the operator such as various printing conditions such as the number of copies to be printed, the number of copies to be printed, and imposition printing instructions, and an output method. Depending on the print conditions and the output method, the printer driver 32 A printer control code recognizable at 20 is generated and output. The printer driver 32 in the present embodiment generates PDL (Page Description Language) data as a printer control code.

  In addition, the printer driver 32 of this embodiment includes a compression processing unit 33. The compression processing unit 33 performs compression processing on the image data output from the application 31. The compression processing performed in the compression processing unit 33 of the printer driver 32 is the same as the compression processing performed on the image data in the compression processing unit 41 of the control unit 21 in the printer 20.

  The printer driver 32 generates the same printer control code as generated by the printer control code generation unit 42 of the control unit 21 in the printer 20 based on the image data output from the application 31. The printer control code output from the printer driver 32 is acquired by the control unit 21 of the printer 20 and stored in the hard disk 23.

  Next, the operation of the printer system of this embodiment will be described with reference to the flowcharts shown in FIGS. The printer system of this embodiment can perform printing based on image data acquired by reading an original image with the scanner 10 and printing based on image data generated by the application 31 of the computer 30. The operation when printing is performed based on the image data acquired by the scanner 10 will be described.

  First, an original image is photoelectrically read by the scanner 10, and the read image data is output to the printer 20 (S10). The image data output from the scanner 10 is acquired by the image data acquisition unit 40 of the printer 20 and temporarily stored in the memory 22 (S12).

  Next, the image data stored in the memory 22 is read, and the read image data is subjected to a cutting process as necessary (S14). This cutting process is performed when, for example, the size of the image data output from the scanner 10 is larger than the size of the printing paper, and the cutting of the image data so that the size of the image data matches the size of the printing paper. This is a process of deleting a part. For example, as shown in FIG. 2, the pixel data in the hatched portions on both sides of the image data is deleted.

  Next, the image data after the cut processing is input to the compression processing unit 41. The compression processing unit 41 inserts the dummy pixel data described above before performing compression processing on the input image data (S16).

  More specifically, the compression processing unit 41 first determines the pixel data of a predetermined row of the image data from the pixel data at the head position (5, 3) including one bit data as shown in FIG. Pixel data up to the rear end (14, 3) pixel data including bit data is cut out. Next, the compression processing unit 41 makes the arrangement shown in FIG. 2 so that the pixel data at the head position (5, 3) is arranged at the original position (5, 3) of the image data before the compression processing after the decompression processing. As shown, dummy pixel data is arranged before pixel data at the head position (5, 3). This dummy pixel data is zero pixel data. In the example shown in FIG. 2, dummy pixel data of 5 pixels is arranged. Further, dummy pixel data is also arranged behind the rear end pixel data as necessary so that the number of pieces of pixel data to be compressed becomes the above-described block unit. In the example shown in FIG. 2, dummy pixel data for one pixel is arranged behind.

  Then, the compression processing unit 41 performs the compression process after arranging the dummy pixel data as described above (S18), and calculates the coordinate value of the leading dummy pixel data for each row together with the compressed image data subjected to the compression process. The data is output to the printer control code generation unit 42.

  Next, the printer control code generation unit 42 generates a printer control code as shown in FIGS. 2 and 3 based on the input compressed image data and the coordinate values of the leading dummy pixel data for each row (FIG. 2). S20). In FIG. 2, only the processing for the pixel data of a predetermined row is shown, but the cut processing, dummy pixel data placement processing, and compression processing similar to the above are performed for the other rows as well. One printer control code is generated for the entire sheet of image data.

  The printer control code generated by the printer control code generation unit 42 is temporarily stored in the hard disk 23 (S22).

  Next, the printer control code stored in the hard disk 23 is read out by the expansion processing unit 43, and the compressed image data included in the printer control code is subjected to expansion processing in units of blocks, as shown in FIG. Image data including pixel data is generated (S24).

  The developed image data is temporarily stored in the memory 22 based on the coordinate code included in the printer control code, and then output to the print engine 24.

  The print engine 24 outputs a control signal to the ink head 25 based on the input image data, and the ink head 25 is driven based on the input control signal to perform printing by ejecting ink onto printing paper. (S26).

  The above is the operation when printing is performed based on the image data acquired by the scanner 10.

  Next, an operation when printing is performed based on image data generated by the application 31 of the computer 30 will be described.

  First, the application 31 is activated, and documents, illustrations, photographic images, and the like are edited using the application 31 to generate image data.

  When a print instruction is selected in the application 31, a user interface of the printer driver 32 is activated and a print condition reception screen for receiving various print conditions and output methods is displayed. Then, after various printing conditions and output methods are set by the operator using predetermined input means on the print condition reception screen, the printer driver 32 is output from the application 31 when a print instruction is selected. After performing the above-described cut processing on the image data, the compression processing unit 33 performs dummy pixel data placement processing and compression processing (S14 to S18), and is set as compressed image data subjected to the compression processing. Based on the printing conditions and the like, the above-described printer control code is generated (S20).

  The printer control code generated in the printer driver 32 is output to the printer 20, acquired by the image data acquisition unit 40 of the printer 20, and then output to the hard disk 23 and stored.

  Thereafter, the printer control code stored in the hard disk 23 is read and the above-described development process is performed (S22), and the printing process is performed based on the image data after the development process in the same manner as described above (S24). ).

  The above is the operation when printing is performed based on the image data generated by the application 31 of the computer 30.

  Next, in the printer system according to this embodiment, an operation when the print instruction condition for imposition processing is set will be described. The imposition process is a process for performing printing by assigning a plurality of images to one print sheet. Here, an operation in the case where two images are printed side by side on one printing sheet will be described first.

  First, after an imposition printing instruction by a user is received in the print instruction receiving unit 26 of the printer 20, the first image data of the two images to be impositioned is output from the scanner 10, Sheet image data is acquired by the image data acquisition unit 40 of the printer 20 and temporarily stored in the memory 22.

  Here, the memory 22 in the present embodiment is assumed to have a storage capacity corresponding to the data amount of image data for one sheet. In the present embodiment, as will be described later, each time one piece of image data is acquired by the image data acquisition unit 40 and is temporarily stored in the memory 22, the image data is read from the memory 22 and subjected to predetermined processing. The image data read from the memory 22 is sequentially discarded from the memory 22. As described above, a plurality of image data to be impositioned are previously arranged on a memory in advance as in the prior art by generating each image code by performing predetermined processing every time one piece of image data is acquired. Compared with the case of generating attached image data, the storage capacity of the memory 22 can be reduced, and the cost can be reduced. In this embodiment, as described above, the memory 22 has a storage capacity corresponding to the data amount of one piece of image data. However, the present invention is not limited to this, and data of one piece of image data is used. Any storage capacity that is larger than the capacity and smaller than the data capacity of the image data for two sheets may be used.

  Then, one piece of image data stored in the memory 22 is read out, and the one piece of read image data is cut according to the paper size of the printing paper.

  FIG. 5 shows left side image data and right side image data to be impositioned in the present embodiment. Specifically, in FIG. 5, two pieces of image data having a size in the X direction of 16 pixels (3 bytes × 2 = 6 bytes) and a paper size in the X direction of 24 pixels (3 bytes × 3 = 9 bytes) The left side image data and the right side image data in the case of printing on the printing paper are shown.

  First, a process of deleting two pixels at the left end and two pixels at the right end is performed on one piece of image data on the left side of the two pieces of image data shown in FIG.

  Then, one piece of image data after the cut processing is input to the compression processing unit 41. Next, the second image data output from the scanner 10, that is, the right-side image data is acquired by the image data acquisition unit 40 of the printer 20, temporarily stored in the memory 22, and then read from the memory 22. The same cut processing as described above is performed and input to the compression processing unit 41.

  Next, the compression processing unit 41 inserts dummy pixel data before performing compression processing on the input image data. Here, a case where dummy pixel data is inserted into the pixel data of the third and fifth rows of the pixel data of each row of the left and right image data will be described. Assume that dummy pixel data insertion processing is performed.

  Specifically, as shown in FIG. 5, the compression processing unit 41 determines that the pixel data in the third row of the left-side image data is 1 from the pixel data at the head position (5, 3) including one bit data. After the pixel data up to the rear end (11, 3) pixel data including the bit data is extracted, the pixel data at the head position (5, 3) is the original position of the image data after compression processing and before compression processing. The dummy pixel data of 5 pixels is arranged before the pixel data at the head position (5, 3). Further, dummy pixel data of 4 pixels is also arranged behind the pixel data at the rear end (11, 3) so that the number of pixel data to be compressed is in block units.

  Similarly, with respect to the pixel data in the fifth row of the left-side image data, the pixel at the rear end (10, 5) including 1 bit data from the pixel data at the head position (1, 5) including 1 bit data is similarly applied. After cutting out the pixel data up to the data, the head position (1, 5) is arranged so that the pixel data at the head position (1, 5) is arranged at the original position of the image data after the decompression process and before the compression process. One pixel of dummy pixel data is arranged before the pixel data. Further, dummy pixel data of 5 pixels is also arranged behind the pixel data at the rear end (10, 5) so that the number of pixel data to be compressed is in block units.

  As for the right side image data, as described above, when printing on a printing paper having a paper size in the X direction of 24 pixels (3 bytes × 3 = 9 bytes), as shown in FIG. In this case, printing is started from the position of X = 12. That is, the X coordinate of the leftmost pixel data of the right side image data is X = 12, as shown in FIG.

  First, with respect to the pixel data of the third row, as shown in FIG. 5, the rear end (23, 3) including 1 bit data from the pixel data at the head position (16, 3) including 1 bit data. After cutting out the pixel data up to the pixel data of the first position, the start position is such that the pixel data at the start position (16, 3) is printed at the position (16, 3) in the coordinate system of the printing paper after the expansion process. The dummy pixel data of 8 pixels is arranged before the pixel data. Further, dummy pixel data of one pixel is also arranged behind the pixel data at the rear end (22, 3) so that the number of pixel data to be compressed is a block unit.

  Similarly, with respect to the pixel data in the fifth row of the left-side image data, the pixel at the rear end (21, 5) including 1 bit data from the pixel data at the head position (12, 5) including 1 bit data. After cutting out the pixel data up to the data, the head position (12, 5) is printed at the position (12, 3) in the coordinate system of the printing paper after the expansion processing so that the pixel data at the head position (12, 5) is printed. , 5) 4 pixel dummy pixel data is arranged before the pixel data. Then, dummy pixel data of two pixels is also arranged behind the pixel data at the rear end (21, 5) so that the number of pixel data to be compressed is in block units.

  Then, after arranging the dummy pixel data as described above, the compression processing unit 41 separately performs compression processing on the left-side image data and the right-side image data to generate two compressed image data. Then, the compression processing unit 41 outputs the coordinate value of the leading dummy pixel data for each row to the printer control code generation unit 42 for each compressed image data together with the two compressed image data.

  Next, in the printer control code generation unit 42, the left side coordinates as shown in FIG. 5 are based on the input compressed image data and the coordinate values of the leading dummy pixel data for each row for each compressed image data. One printer control code composed of the code and the image code and the right side coordinate code and the image code is generated.

  The printer control code generated by the printer control code generation unit 42 is temporarily stored in the hard disk 23.

  Next, a printer control code stored in the hard disk 23 is read by the expansion processing unit 43, and the compressed image data included in the printer control code is subjected to expansion processing in units of blocks. Is stored in the memory 22.

  Here, in this decompression process, the decompression process is separately performed on the compressed image data on the left side and the compressed image data on the right side. If the image data of the left side and the image data after the development of the first block of the compressed image data on the right side are developed and stored in the memory 22, for example, When the image data that has been subjected to the decompression processing of the first block of the compressed image data on the right side is stored after storing the image data of the left side, as shown in FIG. The pixel data from 8 to 11 are overwritten by the dummy pixel data of the first block that has been subjected to the development processing on the right side, and the image information is lost. Conversely, for example, after storing the decompressed image data of the first block of the compressed image data on the right side, when the expanded image data of the rear end block of the compressed image data on the left side is stored, The pixel data of X = 12 to 16 in the rear end block after the development processing on the right side is overwritten by the dummy pixel data of the rear end block after the development processing on the left side, and the image information is lost.

  Therefore, in the present embodiment, as shown in FIG. 5, an OR operation is performed between the image data on which the rear end block of the left side image data is expanded and the image data on which the first block of the right side image data is expanded. The image data obtained as a result of the OR operation is stored in the memory 22. At this time, when the image data of the first block of the left side image data and the rear end block of the right side image data are expanded, the OR operation is not performed.

  When decompressing compressed image data adjacent in the compression (decompression) direction in this way, the OR operation is performed on the decompressed image data of the adjacent blocks, so that the image data on the left and right surfaces is shown in FIG. Thus, it is possible to develop appropriate image data for printing without losing the image information.

  In the present embodiment, the OR operation is performed as described above so that the image information of the left side image data and the right side image data is not lost. However, the calculation method is not limited to this, and both Any calculation method may be used as long as the image information is not lost. For example, mask calculation may be performed. In addition to the OR operation, an AND operation, an XOR operation, a NOT operation, a COPY operation, or the like may be used. Further, the calculation method at this time can be included as information on the calculation method at the time of the expansion process in the image code of the printer control code described above, and the print instruction receiving unit 26 can select one of a plurality of calculation methods by the user. A predetermined calculation method may be selectable from the above.

  The developed image data is temporarily stored in the memory 22 based on the coordinate code included in the printer control code, and then output to the print engine 24.

  Next, the print engine 24 outputs a control signal to the ink head 25 based on the input image data, and the ink head 25 is driven based on the input control signal to print by ejecting ink onto the printing paper. I do.

  The above explanation is an operation when imposition printing is performed based on two pieces of image data read by the scanner 10, but imposition printing is performed based on image data generated by the application 31 of the computer 30. Also in the case of performing, the image data output from the application 31 is subjected to the same cut processing, dummy pixel data arrangement processing, and compression processing as described above to generate a printer control code.

  The printer control code generated by the printer driver 32 of the computer 30 is output to the printer 20, acquired by the image data acquisition unit 40 of the printer 20, and then output to the hard disk 23 and stored.

  Then, after that, the printer control code stored in the hard disk 23 is read, and the expansion process including the OR operation similar to the above is performed, and the printing process is performed based on the image data after the expansion process.

  In the above description, two pieces of image data whose size in the X direction is 16 pixels (3 bytes × 2 = 6 bytes) are schematically shown, and the paper size in the X direction is 24 pixels (3 bytes × 3 = 9 bytes). In the following description, the image data obtained by reading the original image at 300 dpi is arranged side by side on the A4R size printing paper as shown in FIG. The operation will be described.

  When two sets of image data read at 300 dpi are printed side by side on an A4R size printing paper, the image data is first subjected to reduction processing at a predetermined reduction rate, as shown in FIG. As shown, left side image data A and right side image data B of 1753 pixels × 2480 pixels are generated. Here, in order to simplify the description, it is assumed that the image data A on the left side and the image data B on the right side shown in FIG. 6B are valid pixel data in which all pixel data has 1 bit data. To do.

  When the left side image data A and the right side image data B are arranged side by side and subjected to compression processing, the compression processing is performed in units of blocks of 8 pixels (3 bytes) as described above. As shown in FIG. 6C, the boundary between the image data A on the left side and the image data B on the right side is between the 1753rd pixel and the 1754th pixel from the left end, and the position of 1752 pixels which is a multiple of the block unit. Is shifted by one pixel.

  Therefore, since the left side image data A is subjected to compression processing in units of blocks, dummy pixel data of 7 pixels is arranged behind the rear end block as shown in FIG. 6D, and this dummy pixel data is included. Thus, compression processing is performed in units of blocks.

  On the other hand, for the image data B on the right side, as shown in FIG. 6E, the top block pixel data is printed at the 1754th pixel position in the print paper coordinate system after the expansion process. 1 pixel of dummy pixel data is arranged in front of. Further, since the position of the pixel data at the rear end of the image data B on the right side is 1753 pixels × 2 = 3506 pixels, as shown in FIG. It will be. Therefore, in order to compress the pixel data at the rear end of the image data B on the right side in units of blocks, dummy pixel data of 6 pixels is arranged behind the rear end block as shown in FIG. 6E. After dummy pixel data is arranged for the image data B on the right side as described above, compression processing is performed in units of blocks including this dummy pixel data.

  Then, based on the left side compressed image data and the right side compressed image data generated as described above, a printer control code is generated in the same manner as described above, and is temporarily stored in the hard disk 23.

  Next, the printer control code stored in the hard disk 23 is read out and subjected to expansion processing. At this time, as in the case of the imposition printing described above, the expansion processing of the rear end block of the left-side image data has been completed. And the image data obtained by developing the first block of the right side image data are subjected to an OR operation, and the image data obtained as a result of the OR operation is stored in the memory 22. At this time, the OR operation is not performed when developing the image data of the blocks other than the rear end block of the left image data and the blocks other than the head block of the right image data.

  The developed image data is temporarily stored in the memory 22 based on the coordinate code included in the printer control code, and then output to the print engine 24.

  The above is the operation in the case of imposing and printing the image data of the A4 size original image side by side on the A4R size printing paper.

  In the above description, the so-called two-side-up compression processing, decompression processing, and printing processing for printing two pieces of image data on one printing sheet have been described. The same processing can be applied to such a four-sided up or a further eight-sided up.

  For example, in the case of four-sided printing of image data of one to four surfaces as shown in FIG. 7, as shown in FIG. Is subjected to the same compression processing as above, and a coordinate code and an image code are generated for the image data of each surface, and a printer control code comprising the coordinate code and image code of each surface as shown in FIG. Is generated. It is assumed that the coordinate code of each surface of the printer control code generated at this time includes the coordinates of the printing position on the printing paper of each surface.

  Then, the same expansion processing as described above is performed on the compressed image data of each surface included in the image code of the printer control code. At this time, when developing the adjacent blocks in the one-side image data and the two-side image data in the same manner as described above, the one-side image data and the two-side image data are not overwritten with each other. Is subjected to an OR operation. Similarly, in order to prevent the three-side image data and the four-side image data from being overwritten with each other, development processing of adjacent blocks in the three-side image data and the four-side image data is performed in the same manner as described above. In this case, an OR operation is performed.

  Then, the image data of each surface that has been subjected to the expansion process is arranged based on the coordinate value of the print position included in the coordinate code to generate image data for four-up printing. The print image data is stored in the memory 22. Is once stored, and then output to the print engine 24.

  In the above description, the case has been described in which image data of one to four sides is arranged and printed in order from the upper left, but this order is not necessarily required, and the coordinate code of each side of the printer control code is designated. Accordingly, it is possible to print image data from one side to four sides with the arrangement as shown in FIG. The designation of the coordinate code of each surface can be received by the print instruction receiving unit 26 of the printer 20 or the printer driver 32 of the computer 30.

  Further, the printer control code in the above embodiment can further include additional information such as a character image code as shown in FIG. This character image code is for printing characters such as the number of pages and date as shown in FIG. The character image code is a compressed image generated by performing the same compression process on one piece of image data composed of pixel data of a character image representing the number of pages and zero pixel data. It consists of data.

  When the printer control code including the character image code as described above is expanded, the image data expanded from the compressed image data included in the image code and the character expanded from the compressed image data included in the character image code. By performing an OR operation with the image data, it is possible to generate image data for printing as shown in FIG. Note that this OR operation information can also be included as operation method information during the expansion process in the printer control code.

  Further, when the above-described character image such as the number of pages is printed in the white square as shown in FIG. 12, the white image code as shown in FIG. May be further included. This white image code is obtained from compressed image data generated by performing the same compression process as described above on one piece of image data composed of zero pixel data and one pixel data representing a white square. It is composed.

  When the printer control code including the white image code as described above is expanded, the image data obtained by expanding the compressed image data included in the image code and the compressed image data included in the white image code are expanded. An AND operation is performed on the whitened image data, and then an OR operation is performed between the result of the AND operation and the character image data obtained by developing the compressed image data included in the character image code. The image data for printing as shown in FIG. Note that the information of the AND operation and the OR operation can also be included as information on the operation method in the expansion process in the printer control code.

  Note that the additional information included in the printer control code is not limited to the character image code and the white image code as described above, and an image code representing another additional image can also be used.

  In the above embodiment, an ink jet printer is used as the printer 20, but the present invention is not limited to this, and a stencil printer, a laser printer, or the like can also be used.

DESCRIPTION OF SYMBOLS 10 Scanner 20 Printer 21 Control part 22 Memory 23 Hard disk 24 Print engine 25 Ink head 26 Print instruction reception part 30 Computer 31 Application 32 Printer driver 33 Compression processing part 40 Image data acquisition part 41 Compression processing part 42 Printer control code generation part 43 Expansion | deployment Processing part

Claims (9)

An image data acquisition unit that acquires image data that is image data to be printed on a printing paper and that includes a plurality of pixel data represented by a plurality of bit data;
Compressed image data obtained by subjecting the image data acquired by the image data acquisition unit to compression processing in units of blocks consisting of one or more byte units delimited by the boundary of the pixel data in the arrangement direction of the bit data A compression processing unit for generating
A decompression processing unit that performs decompression processing in units of blocks on the compressed image data generated by the compression processing unit, and outputs the image data subjected to the decompression processing;
The compression processing unit prints the top position pixel data including one bit data of the pixel data arranged in the arrangement direction of the bit data at a desired position on the printing paper. An image processing apparatus for performing the compression processing after dummy pixel data is arranged before pixel data.   The compression processing unit arranges dummy pixel data before the pixel data at the head position so that the pixel data at the head position is arranged at the original position of the image data before the compression processing after the decompression process. The image processing apparatus according to claim 1, wherein: The image data acquisition unit acquires a plurality of the image data;
An imposition print instruction accepting unit for accepting an imposition print instruction for arranging and printing a plurality of image data obtained by the image data obtaining unit on one print sheet;
The expansion processing unit performs expansion processing on the compressed image data arranged adjacent to the arrangement direction of the bit data when the imposition printing instruction is received by the imposition printing instruction receiving unit. At the same time, the decompressed image data of the first or rear end block of one of the compressed image data and the decompressed image data of the other compressed image data block adjacent to the first or rear end block; Are applied to the decompressed image data of the block adjacent to the leading or trailing end block of the one compressed image data and the leading or trailing end block of the other compressed image data. The image processing apparatus according to claim 1, wherein the image processing apparatus performs the following calculation.   The image processing apparatus according to claim 3, wherein the predetermined operation is an OR operation.   5. The image processing apparatus according to claim 3, wherein the compression processing unit performs compression processing separately on the plurality of image data to generate a plurality of compressed image data.   The expansion processing unit separately performs expansion processing on the plurality of compressed image data, and sequentially outputs the plurality of image data subjected to the expansion processing based on the imposition printing instruction. The image processing apparatus according to claim 5, wherein:   7. A print control code generation unit that generates the compressed image data and additional information data representing predetermined information added to the image data collectively as a print control code. The image processing apparatus according to claim 1. A printing apparatus comprising: the image processing apparatus according to any one of claims 1 to 7; and a printing unit that performs a printing process on printing paper based on image data output from the image processing apparatus;
A printing system comprising: a document reading device that photoelectrically reads a document image and outputs the image data to the image processing device. A computer comprising the image data acquisition unit and the compression processing unit in the image processing apparatus according to any one of claims 1 to 7,
A printing system comprising: the development processing unit in the image processing apparatus; and a printing apparatus including a printing unit that performs a printing process on print paper based on image data output from the development processing unit. .