JP6202908B2 - Image processing apparatus, image processing method, and program - Google Patents

Description

  The present invention relates to a technique for increasing the line width.

  In image forming apparatuses such as copying machines, laser printers, and ink jet printers, there are many factors that cause fluctuations in fine line reproduction. For example, in the case of electrophotography, influences such as density fluctuations, toner scattering, and process characteristics in the main scanning / sub-scanning directions are likely to appear significantly. These lead to differences between models, individual differences, changes over time, output differences depending on the media conveyance direction, and the like. Further, when printing from the host terminal, the reproduction of thin lines differs depending on the rule for assigning vector drawing to actual pixels, that is, the painting rule, depending on the page description language (PDL) to be used. These are issues relating to faithful reproduction, but only faithful reproduction is not necessarily expected. When printing from the host terminal, it may appear finer than the user expects due to the difference between the display resolution of the host terminal and the output resolution of the image forming apparatus. There is also a need to match the reproduction width of thin lines when using multiple types of image forming apparatuses at the same time, or when replacing image forming apparatuses. In order to solve these various problems, various fine line correction techniques have been proposed to date.

  For example, Patent Document 1 discloses a technique for issuing a PDL drawing command including a command for drawing a thin line and an instruction for correcting a line width specified by the command. However, in general PDL, text is expressed as an outline font. Outline fonts only define the curves that make up the outline of the text, not the width of the lines (stems). Therefore, it is not possible to use a method of simply adjusting the line width like a command for drawing a thin line. Some text is expressed as a bitmap font. In this case, there is no outline font information.

  Patent Document 2 discloses a technique using pattern matching as a technique for correcting the width of a fine line included in a text. However, thickening by pattern matching tends to generate directivity depending on a predefined pattern. For example, let us consider a case where a pixel of interest is added when the pixel above or to the left of the pixel of interest is a pixel constituting text. In this case, the horizontal line and the vertical line are added by one pixel. As for the 45 degree diagonal line, a line drawn from the upper left to the lower right is added by 2 pixels. A line drawn from the upper right to the lower left is added by one pixel. In this way, the way of weighting varies depending on the line drawing direction. Although it is only necessary to increase the thickness in all directions, up, down, left, and right, there is a concern that the pixel will always increase by 2 pixels and become too fat. That is, directivity is an issue in the fine line correction by pattern matching.

JP 2009-105827 A Japanese Patent Laid-Open No. 2007-125827

  Considering the characteristics of the prior art, it is considered preferable to correct the line width at the vector data stage for lines such as straight lines and curves, and to correct the line width by pattern matching for text. However, in the method of specifying the correction amount separately, there is a possibility that a difference occurs in how the text and the line are thickened. This is because the method of thickening the line width by pattern matching is to increase the thickness in pixel units, whereas the logical line width needs to be increased at the vector data stage. Many PDLs define a logical coordinate system as a coordinate space for drawing in order to eliminate device dependency. If the line is thickened in the logical coordinate system, it is possible to thicken the line without depending on the output resolution. However, this also leads to a difference in the number of pixels to be fat depending on the output resolution, resulting in text thickening and mismatch due to pattern matching. Also, when performing layout control such as N-UP processing in which a plurality of pages are arranged on one medium, a mismatch occurs due to reduction.

  Therefore, an object of the present invention is to increase the line width effectively with a simple operation.

  An image processing apparatus according to the present invention includes: a setting unit that sets a line width; and vector data that is the print data so as to change a line width included in the print data in accordance with the line width set by the setting unit. Definition means for defining the image, generation means for generating bitmap data based on the vector data defined by the definition means, and text included in the print data according to the line width set by the setting means Image processing means for performing image processing on the bitmap data so as to change the width of the bitmap data.

  According to the present invention, it is possible to effectively increase the line width with a simple operation.

1 is a diagram illustrating a configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 3 is a diagram illustrating a configuration of a software module of the image forming apparatus according to the embodiment of the present invention. It is a figure which shows the setting screen of the line | wire width correction | amendment displayed on the liquid crystal touch panel of an operation part. It is a flowchart which shows the basic print process performed with a controller unit. It is a figure for demonstrating redefinition of line width designation | designated PS operator. It is a figure for demonstrating how line width becomes thick in an output image. 6 is a flowchart showing in detail a process of a thread C in the basic print process shown in FIG. It is a flowchart which shows the detail of the process which thickens a text by pattern matching performed in step S1212 of FIG. It is a figure which shows the example which applied the process which thickens a text by the pattern matching demonstrated using FIG. It is a figure for demonstrating the subject which the 2nd Embodiment of this invention solves. It is a flowchart which shows the process for detecting the overlap of a text and a line. It is a flowchart which shows the detail of the process which thickens a text by pattern matching performed in step S1212 of FIG. FIG. 9 is a flowchart showing a process executed in place of the process shown in FIG. 8 in the third embodiment of the present invention. FIG.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments to which the invention is applied will be described in detail with reference to the accompanying drawings.

  First, a first embodiment of the present invention will be described. FIG. 1 is a diagram showing a configuration of an image forming apparatus 100 according to the first embodiment of the present invention. In this embodiment, the case of the image forming apparatus 100 alone is taken as an example, but a configuration in which many processes are separately executed on a host computer connected via a network may be employed.

  In FIG. 1, reference numeral 200 denotes a controller unit that controls input / output of image data and device information. The CPU 1 reads the program stored in the ROM 3 or the HDD 4 into the RAM 2 and executes it. Further, the CPU 1 comprehensively controls each device connected to the system bus 5. The RAM 2 functions as a main memory and work area for the CPU 1. The ROM 3 stores a boot program that is executed when the power is turned on, and the HDD 4 stores an operating system and a control program for the image forming apparatus 100. The HDD 4 is also used for temporarily or long-term holding large-capacity data such as image data and print data.

  The network I / F 6 is an interface with the local area network 13 and inputs and outputs print data and device information. The operation unit I / F 7 is an interface with the operation unit 14 and outputs image data to be displayed to the operation unit 14. The operation unit I / F 7 serves to transmit information input from the operation unit 14 by the user of the image forming apparatus 100 to the CPU 1. The operation unit 14 includes a liquid crystal panel and a sound source as an output device, and includes a touch panel and hard keys as input devices.

  The controller unit 200 is connected to the printer engine 15 via the device I / F 8. The device I / F 8 performs image data transmission processing, device operation instruction processing, and device information reception processing based on an instruction from the CPU 1. The printer engine 15 is an output unit that outputs the image data input from the controller unit 200 onto a medium, and may be either an electrophotographic system or an inkjet system.

  A RIP (Raster Image Processor) 9 is dedicated hardware for developing a display list (hereinafter referred to as DL) into a raster image. This display list is intermediate data in a format that RIP 9 can interpret. The RIP 9 processes the DL generated on the RAM 2 by the CPU 1 at high speed and in parallel with the execution of the CPU 1. The printer image processing unit 10 performs image correction, halftoning, and the like on the print output image data. The image rotation unit 12 performs image data rotation processing. The image companding unit 11 performs JPEG compression / decompression processing for multi-valued image data, and JBIG, MMR, and MH format compression / decompression processing for binary image data.

  FIG. 2 is a diagram illustrating a configuration of a software module of the image forming apparatus 100 according to the first embodiment. Each software module shown in FIG. 2 is stored as a program in the HDD 4, loaded into the RAM 2, and executed by the CPU 1. More specifically, each software module is loaded into the RAM 2 by an OS (operating system) that operates on the CPU 1, is given execution rights in units of threads, and is executed.

  The data receiving unit 201 receives print data transmitted from the host terminal. The print data received by the data receiving unit 201 is held by the job data management unit 208 via the job control unit 202.

  The job control unit 202 is responsible for overall job control from print data reception processing to print processing. The PS interpreter 203 interprets PostScript (registered trademark) data and generates DL as intermediate data. The generated DL is held in the job data management unit 208 via the job control unit 202. The renderer 204 is a module that generates a bitmap image from the DL, and many processes are executed by the dedicated hardware RIP 9. The generated bitmap image is held in the job data management unit 208 via the job control unit 202. The printer driver 205 executes print instruction processing and bitmap image transmission processing for the printer engine 15 via the device I / F 8. At this time, the printer driver 205 also performs image correction by the printer image processing unit 10. The user interface 206 is a module that controls the operation unit 14 via the operation unit I / F 7. Mainly, the user interface 206 generates data to be displayed on the liquid crystal panel of the operation unit 14 and updates the display of the liquid crystal panel according to the input from the touch panel. If the input from the touch panel is a job execution instruction, the user interface 206 transmits the instruction to the job control unit 202. The job data management unit 208 is a database that manages print data, DL, and bitmap images temporarily or for a long term.

  FIG. 3 is a diagram showing a line width correction setting screen displayed on the liquid crystal touch panel of the operation unit 14. In the “line width correction” item 301, when “ON” 302 is pressed, the line width correction is enabled, and when “OFF” 303 is pressed, the line width correction is disabled. In addition, in the “weighting width (pixel)” item 304, when “1” 305 is pressed, the thickness is set to 1 pixel, and when “2” 306 is pressed, the thickness is 2 pixels. Is set. Here, the CPU 1 determines an item selected from the pressed position on the setting screen, and stores the setting value in the RAM 2. For example, the CPU 1 detects that “ON” 302 on the liquid crystal touch panel is pressed, and stores information that the thin line correction is valid in the RAM 2. Similarly, the CPU 1 detects that the area “1” 305 of the liquid crystal touch panel has been pressed, and stores the information about the width of 1 pixel in the RAM 2.

  FIG. 4 is a flowchart showing print processing executed by the controller unit 200. The process shown in the flowchart of FIG. 4 is realized by reading the program in each software module of FIG. 2 stored in the HDD 4 into the RAM 2 and executing it by the CPU 1. In the process shown in the flowchart of FIG. 4, three threads of thread A, thread B, and thread C are executed in parallel. Each thread is time-shared by the operating system and its execution right is allocated. Since the unit of time division is sufficiently small, three threads can be regarded as operating in parallel. Since the multi-threading process by the operating system is a generally well-known technique, a detailed description thereof is omitted. Thread A, thread B, and thread C are resident threads generated by the operating system when the image forming apparatus 100 is started.

  First, the thread A will be described. In step S <b> 101, the data reception unit 201 receives PS data that is print data, and stores it in the job data management unit 208 via the job control unit 202. In step S102, the PS interpreter 203 sets an affine transformation matrix between logical coordinates and device coordinates in the PS interpreter 203 itself according to the output resolution and layout contents. Assume that the image forming apparatus 100 supports two output resolutions of 600 dpi and 1200 dpi. Further, it is assumed that the image forming apparatus 100 supports two layouts of 1UP for arranging one page on one sheet and 2UP for arranging two pages side by side on one sheet. In PostScript, the reference unit of logical coordinates is a point (one point is 1/72 inch), and the coordinate origin is a point at the lower left corner of the page. The reference unit of the device coordinates is a pixel, and the coordinate origin is a point at the upper left corner of the paper. At this time, when an LTR size (8.5 × 11 inch) page is output at 1 UP and 600 dpi, the affine transformation matrix is (8.333,0,0, −8.333,0,6600). The setting values of the output resolution and layout contents are specified by a job ticket transmitted together with PS data. The setting value set by the job ticket is notified from the job control unit 202 to the PS interpreter 203.

  In step S103, the PS interpreter 203 determines whether or not the line width correction setting is valid. Here, the PS interpreter 203 determines whether the line width correction set value set by the operation unit 14 is effective by reading it from the RAM 2. If the line width correction setting is valid, the process proceeds to step S104. On the other hand, if the line width correction setting is not valid, the process proceeds to step S107.

  In step S104, the PS interpreter 203 acquires the thickening width (the number of pixels for thickening the line width) stored in the RAM 2 as a result of the operation on the setting screen of FIG. As described with reference to FIG. 3, the image forming apparatus 100 supports values of 1 pixel and 2 pixels. In step S105, the PS interpreter 203 obtains a conversion matrix between logical coordinates and device coordinates, and generates a PS code that reversely calculates a logical line width (hereinafter referred to as a logical thickening width) to be thickened from the number of pixels to be thickened. . In step S106, the PS interpreter 203 uses the generated PS code to redefine a line width designation PS operator (setlinewidth) so as to increase the logical width. Details of the redefinition will be described later.

  In step S107, the PS interpreter 203 analyzes the PS data and generates a display list for the page. Here, it should be noted that the process for thickening the logical line width redefined in steps S105 and S106 is executed when the line width is actually designated by the line width designation PS operator in step S107. . That is, in step S107, the PS interpreter 203 executes a process for increasing the logical line width by the specified number of pixels on the PS data. Further, in this embodiment, the process of thickening the logical line width is realized by redefining the line width designation PS operator, but a method of implementing the same in the execution module of the line width designation PS operator is also possible. In any case, by correcting the logical line width when the line width is specified by the line width specifying PS operator, it is possible to correct the line width at the vector data (PS data) stage instead of correcting the rasterized bitmap data. Become.

  In step S108, the PS interpreter 203 notifies the renderer 204 of the completion of display list generation and requests rendering. In step S109, the PS interpreter 203 determines whether or not all pages have been processed. If all pages have been processed, the processing shown in this flowchart ends. On the other hand, if all the pages have not been processed, the process is continued for the remaining pages.

  The processing of the thread B is executed by the renderer 204. In step S111, the renderer 204 waits for the completion of generation of a display list for one page. When notified of the completion of display list generation, the process proceeds from step S111 to step S112. In step S112, the renderer 204 generates bitmap data and an attribute map by rendering using the display list. Here, the generated bitmap data has a gradation of 8 bits for each color of CMYK, and the attribute map has 2-bit information corresponding to each pixel of the bitmap data. The display list includes an attribute flag for each object, and identifies whether the object is graphics, an image, or text. This attribute flag is expanded into an attribute map at the time of rendering. That is, the attribute map indicates whether each pixel is graphics (00), text (01), or image (10).

  In step S113, the renderer 204 saves the bitmap data and attribute map in the job data management unit 208, and requests the printer driver 205 to print. The print request is made by transmitting a rendering end notification to the printer driver 205. The printer driver 205 is executed as a thread C in a thread different from the thread A in order to execute processing in synchronization with the printer engine 15. In step S121, the printer driver 205 that has received the request performs image processing on the bitmap data. Then, the printer driver 205 transmits a print start request command to the printer engine 15 and transfers the image data. The image processing performed here includes a halftoning process and a process of thickening text. Details of step S121 will be described later.

  In step S114, the renderer 204 determines whether rendering of all pages has been completed. When rendering of all pages is completed, the process of thread B ends. On the other hand, if rendering of all pages has not been completed, the process returns to step S111.

  Next, redefinition of the line width designation PS operator will be described with reference to FIG. FIG. 5A shows a PS code redefined so that the line width designation PS operator is thicker by one pixel than the designated width. By causing the PS interpreter 203 to execute this PS code, redefinition of the line width designation PS operator is completed. In FIG. 5A, the contents of the redefined process are shown in the 2nd to 4th lines, and this is changed from the operation of the existing line width designation PS operator by the PS codes in the 1st and 5th lines. In the second line, first, a transformation matrix between the current logical coordinates and device coordinates is obtained (matrix currentmatrix), the first element of the transformation matrix is taken out (0 get), converted into an absolute value (abs), and transformed. It is defined that the magnification is obtained. This value indicates how many pixels a point corresponds to. In the second line, the product of the scaling factor and the logical line width specified by the line width specification PS operator is calculated (dup 3 1 roll mul), and the logical line width (point) is changed to the device line width (pixel). It is defined to convert. The third line defines that the logical line width (point) is calculated when one pixel is thickened by adding 1 to the calculated device line width (1 add) and dividing by the scaling factor (div). Yes. The fourth line defines that the value is set as a line width value (systemdict / setlinewidth get exec). The PS code between the left parenthesis ({) on the first line and the right parenthesis (}) on the fifth line is actually executed when the redefined line width specification PS operator is called. become. FIG. 5B shows a PS code redefined so that the line width designation PS operator is thicker by 2 pixels than the designated width. The difference from FIG. 5A is only in the place where the added value in the third row is 2 (2 add).

  Next, how the line width increases in the output image will be described with reference to FIG. FIG. 6A virtually illustrates a case where a vertical line having a logical line width of 1.8 pixels is designated. One square in the square represents one pixel. Note that for convenience, the notation is associated with a specific resolution, but the logical line width is not related to the resolution. That is, when the output resolution is doubled, one square in FIG. 6A is divided into four squares, and the logical line width becomes 3.6 pixels. The position of the line is designated as the position of the center line, and the drawing is expected to be filled with a thickness of 0.9 pixels on both sides of the center line. FIG. 6B shows a virtual case where the logical line width is increased by 1 pixel to 2.8 pixels. Increasing the thickness of both sides of the center line by 0.5 pixels each increases the line width by 1 pixel. FIG. 6C shows a device line width as a result of converting this into a paint on actual device coordinates. Since only an integer number of pixels can be painted on the device coordinates, the device line width is rounded to 3 pixels. When one pixel is thickened, in the case of a horizontal line or a vertical line, the additional pixels are biased to either the top, bottom, left or right. However, in the case of diagonal lines and curves, additional pixels are not biased in a specific direction by evenly thickening from the center line on the logical coordinates.

  FIG. 7 is a flowchart showing in detail the processing of the thread C (that is, step S121) in the print processing shown in FIG. The process for thread C is executed by the printer driver 205.

  In step S1211, the printer driver 205 waits for reception of a rendering end notification. When a rendering end notification is issued in step S113 of FIG. 4, the process proceeds to step S1212. In step S1212, the printer driver 205 performs image processing on the bitmap data using the attribute map. The contents of the image processing are text thickening processing and halftoning processing, which are hardware processed using the printer image processing unit 10. Details of the process of fattening the text will be described later.

  In step S1213, the printer driver 205 transmits a print start request command to the printer engine 15, and transfers image data. In step S1213, the printer driver 205 also performs synchronization processing with the printer engine 15. The printer engine 15 cannot output more than a predetermined speed. The controller unit 200 needs to wait for the print output of the printer engine 15 when the RIP process is too fast.

  In step S1214, the printer driver 205 determines whether the next page has been rendered. If the next page has been rendered, the process returns to step S1212. If the next page has not been rendered, the process proceeds to step S1215.

  In step S1215, the printer driver 205 determines whether image transfer for all pages has been completed. When the image transfer for all pages is completed, the process proceeds to step S1216. On the other hand, if the image transfer for all pages has not been completed, the process returns to step S1211. In step S <b> 1216, the printer driver 205 transmits a print completion request command to the printer engine 15.

  FIG. 8 is a flowchart showing details of the process of thickening text by pattern matching, which is executed in step S1212 of FIG. In step S121201, the printer driver 205 determines whether the line width correction setting is valid. The printer driver 205 determines whether or not the line width correction setting is valid by reading the setting value of the line width correction set by the operation unit 14 from the RAM 2. If the line width correction setting is valid, the process proceeds to step S121202. On the other hand, when the line width correction setting is invalid, the process shown in FIG. 8 ends.

  In step S121202, the printer driver 205 sets the target pixel as the upper left pixel of the image data. In step S121203, the printer driver 205 determines whether the number of pixels to be thickened is 1 pixel. If the number of pixels to be thickened is 1 pixel, the process proceeds to step S121204. On the other hand, when the number of pixels to be thickened is not 1 pixel (when the number of pixels to be thickened is 2 pixels), the process proceeds to step S121205.

  In step S121204, the printer driver 205 sets the reference pixel as the upper pixel and the left pixel of the pixel of interest. In step S121205, the printer driver 205 sets the reference pixel to four pixels on the top, bottom, left, and right of the target pixel.

  In step S121206, the printer driver 205 determines from the attribute map whether any attribute of the reference pixel is text. If any attribute of the reference pixel is text, the process proceeds to step S121207. On the other hand, if any attribute of the reference pixel is not text, the process proceeds to step S121209.

  In step S121207, the printer driver 205 extracts the color value of the highest density pixel among the reference pixels having the text attribute. In step S121208, the printer driver 205 overwrites the color value of the target pixel with the color value extracted in step S121207. In step S121209, the printer driver 205 determines whether all pixels have been processed. When all the pixels have been processed, the process illustrated in FIG. 8 ends. On the other hand, if the processing for all the pixels has not been completed, the processing moves to step S121210.

  In step S121210, the printer driver 205 sets the target pixel as the next pixel. Then, the process returns to step S121203 to repeat the process. Here, the next pixel means a pixel on the right side in the scan line direction of the target pixel. However, only when the target pixel is the rightmost pixel of the scan line, the leftmost pixel of the scan line one line below becomes the next pixel.

  FIG. 9 is a diagram illustrating a specific example of the process of fattening text by the pattern matching described with reference to FIG. FIG. 9A shows an example in which a part of text is shown in units of pixels. One square cell indicates one pixel. A darkly painted cell is a pixel constituting the text, and an attribute of the attribute map corresponding to the pixel is also a text. FIG. 9B illustrates pixels that are additionally painted when the process of thickening one pixel is performed. An additional pixel is a pixel with a dot in the middle of the cell. Since the reference pixel becomes the upper pixel and the left pixel, the right pixel and the lower pixel will be painted. FIG. 9C shows the result of applying a paint to finally thicken one pixel. FIG. 9D illustrates pixels that are additionally painted when the process of thickening two pixels is performed. Similarly, the additionally painted pixel is a pixel with a dot in the middle of the cell. Since the reference pixels are 4 pixels in the vertical and horizontal directions, the pixels are added in all directions in the vertical and horizontal directions. FIG. 9E shows the result of applying a paint to finally thicken 2 pixels.

  According to the above procedure, the process of thickening the line width at the PS data level, that is, the vector data stage is executed for the line (line), and the process of thickening by pattern matching is executed for the text (character). be able to. Therefore, according to the present embodiment, the line and the text can be consistently thickened by linking the amount of thickening the line width in the vector data stage with the amount of thickening the text. In addition, even when the resolution is changed or when layout processing represented by N-UP processing is performed, the amount of thickening lines and text can be made consistent. Therefore, the operator only needs to set the amount to increase the line width, and can effectively increase the line width by a simple operation.

  Next, a second embodiment of the present invention will be described. Note that the image forming apparatus according to the second embodiment has the same configuration as the image forming apparatus 100 according to the first embodiment shown in FIGS. 1 and 2, and therefore, in the following description, FIG. The reference numerals shown in FIG. 2 are used. In the following, description will be given focusing on differences from the first embodiment.

  FIG. 10A shows an example in which a 45-degree line running from the upper left to the lower right is overlaid on the text shown in FIG. FIG. 10B shows pixels that are additionally painted when the process shown in FIG. 10A is performed to thicken the text by one pixel. An additional pixel is a pixel with a dot in the center of the cell. Since the reference pixel becomes the upper pixel and the left pixel, the right pixel and the lower pixel are painted. FIG. 10C shows a result of performing the painting by finally executing the process of thickening one pixel. As shown in FIGS. 10B and 10C, by thickening the text, the text is eroded on the line, and the line is thinned only by that portion. This effect is very noticeable when the density of the text and line differ greatly. The second embodiment solves such a problem.

  FIG. 11 is a flowchart showing a process for detecting an overlap between a text and a line. The process shown in FIG. 11 is executed in place of step S108 in FIG. That is, in the second embodiment, the process shown in FIG. 11 is executed after step S107 in FIG. 4, and step S109 in FIG. 4 is executed after the process shown in FIG.

  In step S1101, the PS interpreter 203 sets the text line width correction flag to ON. In step S1102, the PS interpreter 203 interprets the PS data and acquires a drawing command.

  In step S1103, the PS interpreter 203 determines whether or not the acquired drawing command is a text drawing command. If it is a text drawing command, the process proceeds to step S1104. On the other hand, if it is not a text drawing command, the process proceeds to step S1105.

  In step S1104, the PS interpreter 203 acquires the bounding box of the text drawn by the text drawing command and adds it to the bounding box list. In step S1105, the PS interpreter 203 determines whether or not the acquired drawing command is a line drawing command. If it is a line drawing command, the process proceeds to step S1106. On the other hand, if it is not a line drawing command, the process proceeds to step S1108.

  In step S1106, the PS interpreter 203 determines whether there is text below the line designated by the line drawing command. Whether there is text below the line is determined by whether there is a bounding box that intersects the line in the bounding box list. That is, when there is a bounding box that intersects with the line, it is determined that there is text below the line, and when there is no bounding box that intersects with the line, it is determined that there is no text below the line. If there is text below the line, the process proceeds to step S1107. On the other hand, if there is no text below the line, the process proceeds to step S1108.

  In step S1107, the PS interpreter 203 sets the text line width correction flag to OFF. In step S1108, the PS interpreter 203 adds the drawing object to the display list.

  In step S1109, the PS interpreter 203 determines whether or not all drawing processing within the page has been completed. If all drawing processes in the page have been completed, the process proceeds to step S1110. On the other hand, if all the drawing processes in the page have not been completed, the process returns to step S1102. In step S1110, the PS interpreter 203 stores the value of the text line width correction flag in the job data management unit 208 in association with the page. Therefore, in the case of PS data composed of a plurality of pages, the values of a plurality of line width correction flags are held in the job data management unit 208.

  FIG. 12 is a flowchart showing details of the process of thickening text by pattern matching, which is executed in step S1212 of FIG. That is, the process shown in FIG. 12 is a process executed in place of the process shown in FIG. 8 in the first embodiment.

  In step S121201 ′, the printer driver 205 determines whether the line width correction setting is valid and the text line width correction flag is ON. The line width correction flag is a line width correction flag related to the page managed by the job data management unit 208. If the line width correction setting is valid and the text line width correction flag is on, the process proceeds to step S121202. On the other hand, if the line width correction setting is invalid, or if the text line width correction flag is off, the process ends. The processing other than step S121201 ′ is the same as the processing with the same reference numeral shown in FIG.

  As described above, with respect to a page in which it is determined that the line overlaps the text, the process of thickening the text by pattern matching is not executed at all. Therefore, according to the second embodiment, it is possible to avoid the adverse effects associated with the overlap of text and lines.

  Next, a third embodiment of the present invention will be described. The image forming apparatus according to the third embodiment has the same configuration as that of the image forming apparatus 100 according to the first embodiment shown in FIGS. 1 and 2, and therefore, in the following description, FIGS. It is assumed that the reference numerals shown in FIG. In the following, description will be given focusing on differences from the first embodiment.

  In the second embodiment, the method of avoiding erosion to the line due to the thickening of the text by performing the process of thickening the text by pattern matching on the page where the line overlaps the text has been described. The third embodiment avoids erosion to the line due to fattening of text by a method different from that of the second embodiment.

  In the first embodiment, there are three types of attributes defined in the attribute map: graphics, image, and text. In the third embodiment, four types of attributes are added to the lines. That is, there are four attributes of image (10), text (01), graphics excluding line (00), and line (11). This is realized by the renderer 204 assigning a line attribute to the drawing object on the display list for which line drawing is designated in step S111 of FIG. When the text is thickened by pattern matching, when the pixel of interest has a line attribute, the process of fattening the pixel is not performed, thereby avoiding erosion of the line due to the thickening of the text.

  FIG. 13 is a flowchart showing details of the process of fattening text by pattern matching in the third embodiment. That is, in the third embodiment, the process shown in FIG. 13 is executed instead of the process shown in FIG. In FIG. 13, steps S121201 and S121202 are the same processes as steps S121201 and S121202 shown in FIG.

  In step S201, the printer image processing unit 10 determines whether the attribute of the pixel of interest is a line. If the attribute of the target pixel is a line, the process proceeds to step S121209. On the other hand, if the attribute of the pixel of interest is not a line, the process proceeds to step S121203.

  The processing in steps S121203 to S121210 in FIG. 13 is the same as the processing with the same reference numerals in FIG. As described above, in the third embodiment, it is determined whether or not the attribute of the pixel of interest is a line in step S201, and if the attribute of the pixel of interest is a line, the process of fattening the text is skipped. Thereby, it is possible to simultaneously realize the thickening of the text and the thickening of the line while completely preventing the erosion to the line due to the thickening of the text.

  The present invention 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, or the like) of the system or apparatus reads the program. It is a process to be executed.

  201: Data receiving unit, 202: Job control unit, 203: PS interpreter, 204: Renderer, 205: Printer driver, 206: User interface, 208: Job data management unit

Claims (6)

A setting means for setting the line width;
Defining means for defining vector data as the print data so as to change the width of a line included in the print data according to the line width set by the setting means;
Generating means for generating bitmap data based on the vector data defined by the defining means;
Image processing means for performing image processing on the bitmap data so as to change the width of text included in the print data in accordance with the line width set by the setting means Processing equipment.   The definition means uses the conversion matrix between logical coordinates and device coordinates, and calculates the line width in the logical coordinates from the line width to be fattened in the device coordinates set by the setting means. The image processing apparatus according to claim 1, wherein: A determination means for determining whether text and lines are drawn in an overlapping manner in the print data;
3. The image processing unit according to claim 1, wherein the image processing unit does not perform image processing on the bitmap data when it is determined by the determination unit that text and a line are drawn in an overlapping manner. Image processing apparatus.   The image processing apparatus according to claim 1, wherein the image processing unit does not perform the image processing on line attribute data in the bitmap data. An image processing method executed by an image processing apparatus,
A setting step to set the line width;
A definition step for defining vector data that is the print data so as to change the width of a line included in the print data according to the line width set by the setting step;
Based on the vector data defined by the defining step, a generating step for generating bitmap data;
An image processing step of performing image processing on the bitmap data so as to change a width of text included in the print data in accordance with a line width set in the setting step. Processing method. A setting step to set the line width;
A definition step for defining vector data that is the print data so as to change the width of a line included in the print data according to the line width set by the setting step;
Based on the vector data defined by the defining step, a generating step for generating bitmap data;
A program for causing a computer to execute an image processing step of performing image processing on the bitmap data so as to change a width of text included in the print data in accordance with a line width set in the setting step .

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