JP2009141529A - Device and method for processing image, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and a method for processing images and a program capable of improving the flexibility in jaggy correction with respect to image data made to be printed by an ink-jet printer. <P>SOLUTION: The device for processing the image carries out image processings, regarding the image data printed by the ink-jet printer. The device for processing the image has a correction-kind input means for receiving the specifications of kinds of jaggy corrections, regarding the image data and a reference-pattern determining means determining reference patterns used for pattern matching on the basis of kinds of jaggy corrections, and the device for processing the image, further, has a correction means conducting the pattern, matching the image data by using the reference pattern and carrying out processing, corresponding to the kind of correction regarding specified pixels within a matched range, and thereby solving the problem. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image processing apparatus, an image processing method, and a program, and more particularly to an image processing apparatus, an image processing method, and a program that execute image processing related to image data to be printed by an inkjet printer.

  The recorded image of the ink jet printer is represented by dots formed in a matrix in the scanning direction of the head and the transport direction of the recording paper, which is a direction perpendicular thereto. Here, when a character is printed as a dot image, the quality of the character varies greatly depending on the resolution of the image to be printed. For example, when characters of the same size are printed at 300 dpi and when printed at 600 dpi, the number of dots that make up the characters differs by a factor of 4, so that when printed at 600 dpi, it can be expressed in more detail. Of course, the character quality is good. In particular, in the shaded portion of a character, dots increase (or decrease) in a staircase pattern according to the resolution, so that when printed at 300 dpi, it becomes easier to be recognized as jagged (jaggy).

Therefore, conventionally, various techniques for correcting jaggies at the stage of processing image data to be printed have been studied (for example, Patent Document 1).
JP 2005-193384 A

  However, there are various methods and results of jaggy correction. In the conventional technique, a jaggy correction result that is desirable from the viewpoint of the developer is selected in advance and such a correction result is obtained by program logic. Was incorporated as.

  Therefore, the same jaggy correction processing is provided for all users, and it is difficult to provide different jaggy correction processing depending on the user.

  The present invention has been made in view of the above points, and it is an object of the present invention to provide an image processing apparatus, an image processing method, and a program capable of improving the flexibility of jaggy correction for image data to be printed by an inkjet printer. To do.

  In order to solve the above problems, the present invention is an image processing apparatus that executes image processing related to image data to be printed by an inkjet printer, and a correction type input unit that receives a specification of a jaggy correction type for the image data; Reference pattern determining means for determining a reference pattern to be used for pattern matching based on the type of jaggy correction, pattern matching is performed on the image data using the reference pattern, and the correction is performed on a predetermined pixel in a matched range. And a correction unit that executes processing according to the type.

  In such an image processing apparatus, the flexibility of jaggy correction for image data to be printed by an inkjet printer can be improved.

  According to the present invention, it is possible to provide an image processing apparatus, an image processing method, and a program capable of improving the flexibility of jaggy correction for image data to be printed by an inkjet printer.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an example of a system configuration in the embodiment of the present invention. In the figure, one or more host computers 10 and one or more printers 20 are connected via a network 30 (whether wired or wireless) such as a LAN (Local Area Network).

  The host computer 10 is a computer that generates print data that can be interpreted by the printer 20 for data generated by an application, and transmits the print data to the printer 20. The host computer 10 executes various types of image processing in the print data generation process. The image processing includes jaggy correction processing. That is, in the present embodiment, the host computer 10 corresponds to the image processing apparatus.

  The printer 20 is an ink jet printer that performs printing based on print data received from the host computer 10. That is, the printer 20 includes a nozzle head, and forms an image on a recording medium (printing paper) by ejecting ink from nozzles provided in the nozzle head. In the present embodiment, it is assumed that the printer 20 can express four gradations, that is, no droplet, small droplet, medium droplet, and large droplet, for one dot on the recording medium. However, the application range of the present invention is not limited to only a printer that can express four gradations per dot.

  FIG. 2 is a diagram illustrating a functional configuration example of the host computer according to the embodiment of the present invention. In the figure, a host computer 10 includes an application 11, a drawing data memory 12, a rasterizer 13, a raster data memory 14, an interface unit 15, a font processing unit 16, a font data memory 17, a correction definition file 18, and a print setting UI unit 19. Etc.

  Image and character print commands issued from the application 11 (for example, image line position / thickness / shape, character font / size / position, etc.) are temporarily stored in the drawing data memory 12. The rasterizer 13 reads and interprets a print command stored in the drawing data memory 12, and if it is a line drawing command, image data (for example, a dot pattern such as a bitmap) according to the designated position and thickness. If it is a character recording command, the corresponding font data is fetched from the font data memory 17 and raster data that can be recorded by the inkjet printer 20 is generated. The raster data is temporarily stored in the raster data memory 14 and output to the ink jet printer 20 via the interface unit 15.

  Expansion of characters into image data is performed by a font processing unit 16 independent of the rasterizer 13. However, the font processing unit 16 and the rasterizer 13 may be integrated. The rasterizer 13 and the font processing unit 16 are generally realized as software such as a printer driver, but one or both of them may be realized as hardware.

  The font processing unit 16 includes a development unit 161 and a jaggy correction unit 162. The expansion unit 161 expands characters into binary image data (font data). The jaggy correction unit 162 performs jaggy correction on the character outline portion in the font data based on the setting contents on the print setting screen displayed by the print setting UI unit 19 and the correction definition file 18. The print setting screen is a screen for setting printing conditions and the like that are generally displayed by a printer driver.

  In this embodiment, an example in which jaggy correction is performed on font data will be described. However, a mode in which similar jaggy correction is performed not only on characters but also on other binary images, for example, diagonal lines of graphics images, is also included in the present invention. Such jaggy correction may be executed by the rasterizer 13 or may be executed by a separately provided jaggy correction means.

  FIG. 3 is a diagram illustrating a hardware configuration example of the host computer according to the embodiment of the present invention. The host computer 10 in FIG. 3 includes a drive device 100, an auxiliary storage device 102, a memory device 103, a CPU 104, an interface device 105, a display device 106, and an input device 107, which are mutually connected by a bus B. And is configured to have.

A program for realizing processing in the host computer 10 is provided by a recording medium 101 such as a CD-ROM. When the recording medium 101 on which the program is recorded is set in the drive device 100, the program is installed from the recording medium 101 to the auxiliary storage device 102 via the drive device 100. The auxiliary storage device 102 stores the installed program and also stores necessary files and data. For example, the correction definition file 18 and the font data are recorded in the auxiliary storage device 102. The memory device 103 reads the program from the auxiliary storage device 102 and stores it when an instruction to start the program is given. The memory device 103 is also used as a storage area corresponding to the drawing data memory 12, the raster data memory 14, the font data memory 17, and the like.

  The CPU 104 realizes functions related to the host computer 10 (for example, the rasterizer 13, the interface unit 15, the font processing unit 16, the print setting UI unit 19, and the like) according to the program stored in the memory device 103. The interface device 105 is used as an interface for connecting to a network. The display device 106 displays a GUI (Graphical User Interface) or the like by a program. The input device 107 includes a keyboard and a mouse, and is used for inputting various operation instructions.

  The program need not be installed from the recording medium 101 and may be downloaded from another computer via a network.

  Hereinafter, the processing procedure by the host computer 10 will be described. First, jaggy correction processing by the jaggy correction unit 162 will be described. The jaggy correction unit 162 according to the present embodiment adds a pixel to be newly printed with small droplets or medium droplets to the pixels related to the boundary of the character outline in the font data, or the pixels already targeted for printing. The jaggy correction of the character outline is performed by changing the drop type.

  FIG. 4 is a diagram conceptually illustrating an example of a part of pixels of font data. In the figure, black circles indicate ink droplets printed based on the pixels. That is, a pixel with a black circle is a printing target. The size of the black circle indicates the size of the ink droplet. Therefore, the addition of a pixel to be printed means the addition of a black circle having a size corresponding to a small droplet or a medium droplet with respect to a pixel having no black circle (hereinafter referred to as “blank pixel”) in FIG. Moreover, the change of the drop type means the change of the size of the black circle. As an initial state of the font data, a pixel to be printed is a large droplet. Specifically, when 1 pixel is represented by 1 byte, 0 is no drop and 255 corresponds to a large drop, the pixel value of the pixel to be printed is set to 255 before correction, and the pixel value not to be printed is 0. It is initialized to.

  Pixels that are the targets of dot addition or dot size change (hereinafter referred to as “correction target pixels”) are determined by pattern matching. A virtual window is used for pattern matching.

  FIG. 5 is a diagram illustrating an example of a virtual window used for pattern matching. In the figure, an m × n pixel window is shown. Here, the pixel indicated as the target pixel is a pixel to be corrected in the pattern matching. Note that the values of m and n may be the same or different.

  Based on the above, the processing procedure of the jaggy correction processing will be described using a flowchart. FIG. 6 is a flowchart for explaining the processing procedure of the jaggy correction processing by the jaggy correction unit.

  First, the first pixel of the font data is set as a target pixel (S101). Subsequently, bitmap data composed of pixels corresponding to an m × n window centered on the target pixel, for example, is extracted from the font data (S102), and the reference pattern prepared in advance with an m × n size reference pattern is extracted. Pattern matching is performed (S103). The reference pattern represents a dot arrangement when the target pixel is a correction target.

  FIG. 7 is a diagram illustrating an example of a reference pattern. In the figure, an example of a reference pattern corresponding to a window size of 3 × 3 is shown. There may be a plurality of reference patterns.

  In the pattern matching, when the extracted bitmap data matches the reference pattern (Yes in S104), the target pixel is corrected (S105). That is, the target pixel is newly set as a print target corresponding to a small droplet or a medium droplet. Alternatively, the drop type of the target pixel is changed. For example, when no drop is represented by 0 and a large drop is represented by 255, the pixel value of a small drop pixel may be set to 85, for example. The pixel value of the medium drop may be set to 170, for example. Note that what correction is performed in which case will be described later.

  Subsequently, the target pixel is moved to the next pixel position (S106), and the processing is repeated from step S102. If the pattern matching does not match (No in S104), step S105 is skipped and the process proceeds to step S106. Such processing is repeated until all the pixels of the font data have been processed (Yes in S107). When there are a plurality of reference patterns to be pattern-matched, the process of FIG. 6 is executed for the plurality of reference patterns.

  Next, processing executed before FIG. 6 will be described. FIG. 8 is a flowchart for explaining preprocessing for jaggy correction.

  At the time of printing instruction by the user, the print setting UI unit 19 displays a print setting screen, and accepts the setting of the correction type (correction type) of the jaggy correction together with the printing conditions (S201). The set correction type is transmitted to the jaggy correction unit 16 and held.

  FIG. 9 is a diagram for explaining the correction type. As shown in the figure, the correction content (correction method) differs depending on the correction type. Specifically, in the correction type 1, the blank target pixel is always a small droplet. The correction type 2 always uses a blank pixel of interest as a medium drop. In the correction type 3, a blank pixel of interest is a small droplet or a medium droplet. That is, the correction result by the correction type 3 can include a small droplet and a medium droplet. The correction type 4 is to change the drop type of the target pixel that is not blank (that is, a large drop) to a medium drop. The correction type 5 is a combination of the correction type 3 and the correction type 4. Thus, the correction type varies depending on the size of the ink droplet applied to the target pixel. In addition, the correction type differs depending on the combination of ink sizes to be applied to the target pixel.

  Note that which correction type is desirable for the correction result depends on the user. This is because even if the character outline portion looks smooth, it may become a thin line character. Therefore, the user-desired jaggy correction can be performed by allowing the user to select the correction type.

  When the start of printing is instructed and a character print command is input from the application 11 to the drawing data memory 12, the jaggy correction unit 162 uses the size of the window used for pattern matching (resolution at the time of printing) based on the output resolution (resolution at the time of printing). m × n value) is determined (S201). The correspondence between the output resolution and the window size may be incorporated as logic in the jaggy correction unit 162 (that is, hard coding) or may be defined in an external file. Basically, the higher the resolution, the larger the window size. Further, the output resolution may be set on a print setting screen displayed by the print setting UI unit 19 when a user instructs printing, or may be automatically determined based on a resolution supported by the printer 20. .

  Subsequently, the jaggy correction unit 162 opens the correction definition file 18 corresponding to the determined window size (S202). That is, in this embodiment, the correction definition file 18 is managed for each window size (in other words, for each resolution).

  FIG. 10 is a diagram illustrating a configuration example of the correction definition file. In the figure, the correction definition file 18 defines a reference pattern corresponding to the window size for each correction type. As the correction type 1 reference pattern, identification information (file name, etc.) of a reference pattern (small droplet addition pattern) for adding a small droplet to the target pixel is registered. As the correction type 2 reference pattern, identification information of a reference pattern (medium drop addition pattern) for adding a medium drop to the target pixel is registered. As the reference pattern of the correction type 3, the identification information of the small droplet addition pattern and the identification information of the medium droplet addition pattern are registered. As the correction type 4 reference pattern, identification information of a reference pattern (droplet type change pattern) for changing a large droplet of a target pixel to a medium droplet is registered. As reference patterns of the correction pattern 5, identification information of a small drop addition pattern, a medium drop addition pattern, and a drop type change pattern is registered.

  Note that the droplet addition patterns in the correction types 1, 3, and 5 are not necessarily the same. Similarly, the medium drop addition pattern in correction types 3 and 5 and the drop type change pattern in correction types 4 and 5 are not necessarily the same.

  Further, the “small droplet addition pattern”, “medium droplet addition pattern”, and “droplet type change pattern” in the figure are not necessarily one reference pattern. A plurality of reference patterns may be registered for each.

  The correction definition file 18 can be easily rewritten. Therefore, the reference pattern according to the correction type can be easily changed.

  Subsequently, the jaggy correction unit 162 determines (determines) a reference pattern corresponding to the correction type set by the user based on the correction definition file 18, and reads the reference pattern onto the memory (S204). Subsequently, the expansion unit 161 expands the font data of the character that is the target of the print command in the font data memory 17 (S205).

  Subsequently, the jaggy correction process described in FIG. 6 is executed (S206). Therefore, the pattern matching in FIG. 6 uses reference pattern data determined based on the resolution and the correction type. In step S105 of FIG. 6, correction according to the correction type is performed.

  For example, in the case of correction type 1, the pixel of interest is a droplet. In the case of correction type 2, the target pixel is a medium drop. In the case of correction type 3, the target pixel when matched with the small droplet addition pattern is a small droplet, and the target pixel when matched with the medium droplet additional pattern is a medium droplet. In the case of correction type 4, the target pixel is changed to a medium drop. In the case of correction type 5, the pixel of interest when matched with the small droplet addition pattern is a small droplet, the pixel of interest when matched with the medium droplet additional pattern is a medium droplet, and attention when matching with the droplet type change pattern The pixel is changed to a medium drop.

  As a result, the following correction result is obtained according to the correction type based on the same source (correction source font data). FIG. 11 is a diagram illustrating an example of a jaggy correction result corresponding to the correction type.

  In the figure, the top row shows a state (source) before correction. The second row shows the correction type 1 correction result. In the correction result, a small droplet is added to a part of the pixel that was blank. The third row shows correction type 2 correction results. In the correction results, medium drops are added to some of the pixels that were blank. The fourth row shows the correction type 3 correction result. In the correction result, small enemies or medium drops are added to some of the blank pixels. The fifth row shows the correction type 4 correction result. In the correction result, some of the pixels that were large droplets are changed to medium droplets. The sixth row shows the correction type 5 correction result. In the correction result, in the correction result, a small enemy or a medium drop is added to a part of the pixel that is blank, and a part of the pixel that is a large drop is changed to a medium drop.

  As described above, the host computer 10 according to the present embodiment can cause the user to select a correction type for jaggy correction, and executes a correction process according to the selected correction type. Therefore, it is possible to execute jaggy correction according to the user's preference.

  The reference pattern used according to the correction type is defined in the correction definition file 18 that can be easily rewritten. Therefore, the reference pattern corresponding to the correction type can be easily changed without changing the source code of the program related to the jaggy correction unit 162. This means that the contents of the jaggy correction can be easily changed.

  In this embodiment, the example in which the host computer 10 performs jaggy correction has been described. However, the printer 20 may perform jaggy correction. In this case, the printer 20 corresponds to an image processing apparatus.

  As mentioned above, although the Example of this invention was explained in full detail, this invention is not limited to such specific embodiment, In the range of the summary of this invention described in the claim, various deformation | transformation・ Change is possible.

It is a figure which shows the system configuration example in embodiment of this invention. It is a figure which shows the function structural example of the host computer in embodiment of this invention. It is a figure which shows the hardware structural example of the host computer in embodiment of this invention. It is a figure which shows notionally the example of the one part pixel of font data. It is a figure which shows the example of the virtual window used for pattern matching. It is a flowchart for demonstrating the process sequence of the jaggy correction process by a jaggy correction | amendment part. It is a figure which shows the example of a reference pattern. It is a flowchart for demonstrating the pre-process of jaggy correction. It is a figure for demonstrating a correction type. It is a figure which shows the structural example of a correction definition file. It is a figure which shows the example of the jaggy correction result according to a correction type.

Explanation of symbols

10 host computer 11 application 12 drawing data memory 13 rasterizer 14 raster data memory 15 interface unit 16 font processing unit 17 font data memory 18 correction definition file 19 print setting UI unit 19
20 Printer 100 Drive device 101 Recording medium 102 Auxiliary storage device 103 Memory device 104 CPU
105 interface device 106 display device 107 input device B bus

Claims (11)

An image processing apparatus that executes image processing related to image data to be printed by an inkjet printer,
Correction type input means for accepting designation of the type of jaggy correction for the image data;
Reference pattern determining means for determining a reference pattern used for pattern matching based on the type of the jaggy correction;
An image processing apparatus comprising: a correction unit configured to perform pattern matching on the image data using the reference pattern, and to execute a process according to the type of correction on a predetermined pixel in the matched range. A storage unit in which a definition file including information for identifying the reference pattern according to the type of the jaggy correction is recorded;
The image processing apparatus according to claim 1, wherein the reference pattern determination unit determines a reference pattern used for pattern matching using the definition file.   The image processing apparatus according to claim 1, wherein the type of correction differs according to a size of an ink droplet applied to the predetermined pixel.   4. The image processing apparatus according to claim 1, wherein the type of correction differs according to a combination of ink droplet sizes to be applied to the predetermined pixel. 5.   The reference pattern determining means determines the size of the reference pattern according to the resolution at which the image data is printed, and determines a reference pattern used for pattern matching based on the size of the reference pattern and the type of jaggy correction The image processing apparatus according to claim 1, wherein the image processing apparatus is an image processing apparatus. An image processing method executed by an image processing apparatus for image data to be printed by an inkjet printer,
A correction type input procedure for accepting designation of a jaggy correction type for the image data;
A reference pattern determination procedure for determining a reference pattern used for pattern matching based on the type of the jaggy correction;
An image processing method comprising: performing a pattern matching on the image data using the reference pattern, and executing a process according to the type of correction on a predetermined pixel in the matched range. The image processing apparatus includes a storage unit in which a definition file including information for identifying the reference pattern according to the type of the jaggy correction is recorded.
The image processing method according to claim 6, wherein the reference pattern determination procedure determines a reference pattern to be used for pattern matching using the definition file.   The image processing method according to claim 6, wherein the type of correction varies depending on a size of an ink droplet applied to the predetermined pixel.   The image processing method according to claim 6, wherein the type of correction differs according to a combination of ink droplet sizes to be applied to the predetermined pixel.   The reference pattern determination procedure determines the size of the reference pattern according to the resolution at which the image data is printed, and determines a reference pattern used for pattern matching based on the size of the reference pattern and the type of jaggy correction The image processing method according to claim 6, wherein the image processing method is an image processing method.   A program for causing an image processing apparatus to execute the image processing method according to any one of claims 6 to 10.

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