JP2006119709A - Drawing processing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid drawing corruption due to an ROP process on a memory-saving rendering system by avoiding drawing corruption due to the generation of MSK during CMYK rendering, for an area where predetermined ROP is determined and DST remains. <P>SOLUTION: A drawing system that performs rendering in CMYK using a raster operation determines the raster operation designated; converts the CMYK to CMY according to the result determined; determines if an output destination becomes translucent due to the data to be drawn and the raster operation; creates a mask pattern based on the result determined; and changes a rendering process according to the mask pattern created. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a drawing processing system corresponding to ROP (Raster Operation) processing of a drawing model.

In the drawing model of Windows (registered trademark) GDI shown in FIG. 3, Source (hereinafter referred to as SRC), Pattern (hereinafter referred to as PTN), Mask (hereinafter referred to as MSK), Destination (hereinafter referred to as DST) and ROP (Raster Operation). Rendering is performed, and rendering processing is also performed using a similar ROP in other drawing models such as an OS. (Patent Document 1) In the case of corresponding to these drawing models, in a printing apparatus, input RGB data is color-converted into CMYK, rendered using ROP after halftone processing, and halftone bitmap Since the image is stored in the memory, a rendering system that saves memory compared to RGB 24-bit rendering is realized. In rendering processing by CMYK, depending on the combination of SRC, PTN, and DST colors and ROP, rendering may not be performed normally when rendering processing is performed for each CMYK plane. To avoid this problem, SRC, PTN, and DST are converted from CMYK to CMY before rendering, then rendered for each plane in CMY, and after rendering, DST is converted from CMY to CMYK so that a normal output result is obtained. I have to.
Japanese Patent Laid-Open No. 2002-7101

  However, in the drawing fraud avoidance processing in CMYK rendering, for example, pixels with C = 255, M = 255, Y = 255, and K = 0 are replaced with K = 0, and only the ROP processed region is not ROP processed. There is a case where the color becomes different from the selected area and drawing fraud occurs.

  FIG. 4 shows an example of drawing fraud in CMYK rendering when DSa ROP is specified. In the AND processing of SRC and DST, when SRC is white, the color of DST remains as it is. However, in CMYK rendering, DST CMYK is converted to CMY, and after rendering, CMY is converted to CMYK. Therefore, (C, M, Y, K) = (128, 128, 128, 0) becomes (C, M, Y) = (128, 128, 128), and after rendering, (C, M, Y, K) = (0, 0, 0, 128), the color changes from the original DST, and the color is different from that outside the drawing area.

In order to solve the above-described problem, a drawing processing system according to claim 1 of the present invention provides:
In a rendering system that performs rendering in CMYK using a raster operation, a raster operation determination unit that determines a specified raster operation, and a CMY conversion unit that converts CMYK to CMY according to a result determined by the raster operation determination unit A transmission determination unit that determines whether the output destination is transparent by data to be rendered and a raster operation; a mask generation unit that generates a mask pattern based on a result determined by the transmission determination unit; and a mask generation unit And a means for switching a rendering process in accordance with the generated mask pattern.

  The drawing processing system according to the present invention is a rendering processing system that performs rendering in CMYK using a raster operation. According to the raster operation determining means for determining a specified raster operation and the result determined by the raster operation determining means. CMY conversion means for converting from CMYK to CMY, transmission determination means for determining whether the output destination is transparent by data to be drawn and raster operation, and generation of a mask pattern based on the result determined by the transmission determination means A mask generating unit that extracts a shape of a clip region from the mask pattern generated by the mask generating unit, and a unit that performs extraction processing using the clip extracted by the clip extracting unit. The features.

  As described above, according to the present invention, in CMYK rendering, it is possible to avoid drawing fraud due to determination of a predetermined ROP and generation of MSK for an area that remains DST, and drawing fraud due to ROP processing in a memory-saving rendering system. Can be avoided. Further, by converting the generated MSK to the clip area, it is possible to avoid drawing the area that remains as DST, and to improve the performance.

Example 1
Before describing the configuration of the present embodiment, the configuration of a laser beam printer (hereinafter referred to as “LBP”) suitable for application of the present embodiment will be described with reference to FIG. Needless to say, the printer to which the present embodiment is applied is not limited to the laser beam printer, but may be a printer of another printing method. Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view showing the internal structure of the LBP of the embodiment. In the figure, reference numeral 100 denotes an LBP main body, which corresponds to a character pattern corresponding to a character printing command, various graphic drawing commands, image drawing commands, color designation commands, etc. supplied from an externally connected computer (301 in FIG. 2). A figure, an image, etc. are created, and an image is formed on a recording sheet as a recording medium. 151 is a switch for operation and an operation panel provided with an LED display and an LCD display for displaying the status of the printer. 101 is a control of the entire LBP 100 and analyzes a character print command supplied from the host computer. A printer control unit. The LBP in this embodiment converts RGB color information into M (magenta) C (cyan) Y (yellow) K (black), and forms and develops them in parallel. Has a development mechanism. The printer control unit 101 generates a print image for each MCYK, converts it into a video signal, and outputs it to each MCYK laser driver. The M (magenta) laser driver 110 is a circuit for driving the semiconductor laser 111, and switches on and off the laser beam 112 emitted from the semiconductor laser 111 in accordance with an input video signal. The laser beam 112 is swung in the left-right direction by the rotary polygon mirror 113 to scan the electrostatic drum 114. As a result, an electrostatic latent image of a character or figure pattern is formed on the electrostatic drum 114. The latent image is developed by a developing unit (toner cartridge) 115 around the electrostatic drum 114 and then transferred to a recording sheet. C (cyan), Y (yellow), and K (black) have the same image formation / development mechanism as M (magenta), and 120, 121, 122, 123, 124, and 125 are C (cyan) images. Formation / development mechanism, 130, 131, 132, 133, 134, 135 are Y (yellow) image formation / development mechanisms, 140, 141, 142, 143, 144, 145 are K (black) image formation / development mechanisms. Development mechanism. The individual functions are the same as those of the M (magenta) image forming / developing mechanism, and a description thereof will be omitted.

  A cut sheet is used as the recording paper, and the cut sheet recording paper is stored in a paper feed cassette 102 mounted on the LBP and is kept at a certain height by a spring 103. A paper feed roller 104 and transport rollers 105 and 106 are used. Are taken into the apparatus, are placed on the sheet conveying belt 107, and pass through each image forming / developing mechanism of MCYK. Each MCYK toner (powder ink) transferred to the recording paper is fixed to the recording paper by heat and pressure by the fixing unit 108, and the recording paper is output to the upper part of the LBP main body by the conveying rollers 109 and 150.

  FIG. 2 is a block diagram illustrating the configuration of the printing system according to the embodiment of the present invention. A computer 301 edits an image using an application or the like and transmits print data via a printer driver.

  Reference numeral 201 denotes a printing apparatus. Reference numeral 202 denotes a network I / F for inputting / outputting information to / from a device such as a computer 301 connected to the network. Print data from the computer 301 is received via the network I / F 202. A RAM 203 temporarily stores various information. A RAM 203 is a reception buffer 204 that stores print data or image data transmitted from the computer 301 and received via the network I / F 202, and a work memory 205 that is temporarily used when the input data is converted into an intermediate code. A frame buffer 210 for storing an intermediate code in the printer, and a raster memory 211 for storing data obtained by developing the intermediate code.

  Reference numeral 208 denotes a ROM that stores the control code of the CPU 211 in the printing apparatus 201. The ROM 208 analyzes the data read from the reception buffer 204 and distributes the data to predetermined processing, and the ROP determination unit 215 that determines a predetermined ROP of the drawing logic (ROP) setting analyzed by the analysis processing unit. The mask generation unit 209 generates a mask pattern when a predetermined ROP is determined by the ROP determination unit 215, and the expansion processing unit 210 expands the intermediate code stored in the frame buffer 206 and stores it in the raster memory. .

  Reference numeral 211 denotes a central processing unit (CPU) that performs arithmetic processing and control of the printing apparatus 201. An engine I / F 212 inputs and outputs signals to and from the printer engine 213. A printer engine 213 forms a latent image on a photosensitive drum by a known electrophotographic process based on image data, transfers the image onto a sheet, fixes the image, and performs printing.

  FIG. 8 is a flowchart of the printing apparatus according to the embodiment of the present invention.

  When the printing apparatus receives data (S1101), data analysis is started (S1102). In the data analysis, it is checked whether the drawing logic of ROP2 is set when the drawing logic is set (S1103). In the case of ROP2 drawing logic, ROP2 drawing processing is performed (S1104). On the other hand, if it is not ROP2 drawing logic, it is determined whether it is ROP3 drawing logic (S1105). If it is ROP3 drawing logic, ROP3 drawing processing is performed (S1106). If the drawing logic is not ROP3, other processing is performed (S1107). S1102 to S1107 are repeated until the processing of all data is completed. When all the data processing is completed (S1108), rendering processing is performed based on the created MSK, PTN, S and the designated ROP (S1109), and the created raster image is transferred to the engine and printed. (S1110) The process ends.

  FIG. 9 is a flowchart of the ROP2 drawing process in S1104.

  In the ROP2 drawing process, it is determined whether the ROP is a DST when the SRC is black (S1201). In the case of ROP which becomes DST when SRC is black ((ROP2 & 0x3) == 0x2), it is determined whether each pixel of data designated in SRC is black (S1202). When black, MSK is set to 0 (S1203), and when other than black, MSK is set to 1 (S1204). S1202 to S1204 are repeated for all pixels of SRC, and the search of all pixels of SRC is completed (S1205). MSK pattern is set (S1211), and ROP2 is converted to ROP4 (S1212). On the other hand, if the SRC is not a ROP that is a DST when the SRC is black, it is determined whether the ROP is a DST when the SRC is white (S1206). In the case of ROP which becomes DST when SRC is white ((ROP2 & 0xc) == 0x8), it is determined whether each pixel of data designated in SRC is white (S1207). When white, MSK is set to 0 (S1208), and when other than white, MSK is set to 1 (S1209). S1207 to S1209 are repeated for all pixels of SRC, and the search of all pixels of SRC ends (S1210). MSK pattern is set (S1211), and ROP2 is converted to ROP4 (S1212). For ROPs that do not become DST regardless of whether SRC is black or white, the process ends without setting the MSK pattern.

  FIG. 10 is a flowchart of the ROP3 drawing process in S1106.

  In the ROP3 drawing process, it is determined whether the ROP is a DST when the SRC is black (S1301). In the case of ROP which becomes DST when SRC is black ((ROP3 & 0x33) == 0x22), it is determined whether each pixel of data designated in SRC is black (S1302). When black, MSK is set to 0 (S1303), and when other than black, MSK is set to 1 (S1304). S1302 to S1304 are repeated for all pixels of SRC, and the search of all pixels of SRC is completed (S1305). MSK pattern is set (S1311), and ROP3 is converted to ROP4 (S1312). On the other hand, if it is not the ROP that becomes DST when the SRC is black, it is determined whether the ROP becomes DST when the SRC is white (S1306). In the case of ROP that becomes DST when SRC is white ((ROP3 & 0xcc) = 0x88), it is determined whether each pixel of data designated in SRC is white (S1307). If white, MSK is set to 0 (S1308), and if not white, MSK is set to 1 (S1309). S1307 to S1309 are repeated for all pixels in SRC, and the search for all pixels in SRC ends (S1310). MSK pattern is set (S1311), and ROP3 is converted to ROP4 (S1312). For ROPs that do not become DST regardless of whether SRC is black or white, ROP3 drawing processing is further performed for PTN (S1313).

  FIG. 11 is a flowchart of the PTN ROP3 drawing process in S1313.

  In the ROP3 drawing process, it is determined whether the ROP is a DST when the PTN is black (S1401). In the case of ROP that becomes DST when PTN is black ((ROP3 & 0x0f) == 0x0a), it is determined whether each pixel of the data specified in PTN is black (S1402). If black, MSK is set to 0 (S1403), and if not black, MSK is set to 1 (S1404). S1402 to S1404 are repeated for all pixels of PTN, and the search of all pixels of PTN is completed (S1405). MSK pattern is set (S1411), and ROP3 is converted to ROP4 (S1412). On the other hand, when the PTN is not ROP that is DST when the PTN is black, it is determined whether the ROP is DST when the PTN is white (S1406). In the case of ROP that becomes DST when PTN is white ((ROP3 & 0xf0) == 0xa0), it is determined whether each pixel of data specified in PTN is white (S1407). If white, MSK is set to 0 (S1408), and if not white, MSK is set to 1 (S1409). S1407 to S1409 are repeated for all pixels of PTN, and the search of all pixels of PTN is completed (S1310). MSK pattern is set (S1411), and ROP3 is converted to ROP4 (S1412). For ROPs that do not become DST regardless of whether PTN is black or white, the process ends without setting the MSK pattern.

  FIG. 12 is a flowchart of the rendering process in S1109.

  In the rendering process, it is determined whether or not the ROP cannot be CMYK rendered (S1501). If CMYK rendering cannot be performed, it is determined whether the ROP is DST when MSK is 0 (S1502). When MSK is 0 and DST is obtained, S, PTN, and DST of a pixel with MSK 1 are converted from CMYK to CMY, respectively (S1503), and CMY rendering is performed (S1504). After the CMY rendering is completed, the CMY of the DST after rendering of the pixel whose MSK is 1 is converted into CMYK (S1505), and the rendering process is terminated. On the other hand, when MSK is not 0 and DST does not occur, S, PTN, and DST are converted from CMYK to CMY, respectively (S1506), and CMY rendering is performed (S1507). After the CMY rendering is completed, the CMY of the rendered DST is converted into CMYK (S1508), and the rendering process ends. If CMYK rendering can be performed, rendering is performed by each designated ROP of CMYK (S1509), and the rendering process ends.

  An example of the conversion method from ROP2 to ROP4 in S1105 and the conversion method from ROP3 to ROP4 in S1108 is shown in FIG. When DSa of ROP2 and ROP3 is specified, if SRC is white, the rendering result remains as DST. In S1104 ROP2 rendering processing or S1107 ROP3 rendering processing, SRC is 0 for white pixels, otherwise An MSK with 1 is generated. After generating the MSK, the upper 8 bits of ROP4 are converted to 10101010, the lower 8 bits are converted to 8 bits of DSa of ROP3, and ROP2 and ROP3 are converted to 16 bits of ROP4. In the case of DSo, the same method is used to generate an MSK where the SRC is 0 for black pixels and 1 for other pixels, and the following is converted to ROP4 in the same way as DSa.

  As shown in FIG. 5, in the region where the color has changed due to the CMYK → CMY → CMYK conversion in FIG. 4 and the drawing has become invalid, the CMYK → CMY → CMYK conversion is not performed, and normal colors can be output.

(Other examples)
In the first embodiment, ROP is determined, MSK is set so that the pixel in the region serving as DST is 0, and SRC, PTN, and DST pixels in which MSK is 0 are not subjected to CMYK → CMY → CMYK conversion in the rendering process. Although a normal result is obtained, the rendering process of the region serving as the DST may not be performed by taking out the shape of one pixel of the MSK pattern and setting it as the clip region. FIG. 6 is an example of clip area generation with the same data as FIG. 5 of the first embodiment.

1 is a side sectional view showing a structure of a laser beam printer according to an embodiment of the present invention. 1 is a block diagram illustrating a configuration of a printing system according to Embodiment 1. FIG. It is the figure which showed the drawing model of GDI of Windows (trademark). It is a figure which shows an example used as a drawing fraud by CMYK rendering. FIG. 10 is a diagram illustrating an example in which drawing fraud is avoided in CMYK rendering according to the first embodiment. It is a figure which shows the example which avoided the drawing fraud in the CMYK rendering by another Example. FIG. 6 is a diagram illustrating an example of conversion from ROP2, ROP3 to ROP4 according to the first embodiment. 6 is a flowchart of a drawing process in the printing apparatus according to the first embodiment. 10 is a flowchart of ROP2 drawing processing in S1104 according to the first embodiment. 10 is a flowchart of ROP3 drawing processing in S1106 according to the first embodiment. 10 is a flowchart of the PTN ROP3 drawing process in S1313 according to the first embodiment. 10 is a flowchart of rendering processing in S1109 according to the first embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Printer body 101 Printer control unit 102 Paper feed cassette 103 Spring for lifting paper 104 Paper feed roller 105 Paper transport roller 106 Paper transport roller 107 Paper transport belt 108 Fixing device 109 Paper transport roller 110 Laser driver (for magenta)
111 Semiconductor laser emitting device (for magenta)
113 Rotating polygon mirror (for magenta)
114 Electrostatic drum (for magenta)
115 Toner cartridge (for magenta)
120 Laser driver (for cyan)
121 Semiconductor laser emitting device (for cyan)
122 Laser beam (for cyan)
123 Rotating polygon mirror (for cyan)
124 Electrostatic drum (for cyan)
125 toner cartridge (for cyan)
130 Laser driver (for yellow)
131 Semiconductor laser emitting device (for yellow)
132 Laser beam (for yellow)
133 Rotating polygon mirror (for yellow)
134 Electrostatic drum (for yellow)
135 Toner cartridge (for yellow)
140 Laser driver (for black)
141 Semiconductor laser emitting device (for black)
142 Laser beam (for black)
143 Rotating polygon mirror (for black)
144 Electrostatic drum (for black)
145 Toner cartridge (for black)
150 Paper transport roller 151 Operation panel

Claims (7)

In a drawing system that renders in CMYK using raster operations,
Raster operation determination means for determining a specified raster operation;
CMY conversion means for converting from CMYK to CMY according to the result determined by the raster operation determination means;
Transparency determining means for determining whether the output destination is transparent by the data to be rendered and the raster operation;
Mask generating means for generating a mask pattern based on the result determined by the transmission determining means;
A drawing processing system comprising: means for switching rendering processing in accordance with the mask pattern generated by the mask generating means.   2. The drawing according to claim 1, wherein the raster operation is a drawing logic used in a raster operation 2, a raster operation 3, a raster operation 4 or other OS drawing model of Windows (registered trademark) GDI. Processing system.   The CMYK rendering has CMYK rendering means for performing rendering processing for each CMYK plane, and CMY rendering means for performing rendering processing for each CMY plane after converting from CMYK to CMY and converting the output destination from CMY to CMYK. The drawing processing system according to claim 1.   The drawing processing system according to claim 1, wherein the rendering switching unit selects one of the CMYK rendering unit and the CMY rendering unit. In a drawing processing system that renders in CMYK using raster operations,
Raster operation determination means for determining a specified raster operation;
CMY conversion means for converting from CMYK to CMY according to the result determined by the raster operation determination means;
Transparency determining means for determining whether the output destination is transparent by the data to be rendered and the raster operation;
Mask generating means for generating a mask pattern based on the result determined by the transmission determining means;
Clip extraction means for extracting the shape of the clip region from the mask pattern generated by the mask generation means;
A drawing processing system comprising: means for extracting by the clip extracting means and performing rendering processing with the clip.   6. The drawing according to claim 5, wherein the raster operation is a drawing logic used in a raster operation 2, a raster operation 3, a raster operation 4 or other OS drawing model of Windows GDI. Processing system.   The CMYK rendering has CMYK rendering means for performing rendering processing for each CMYK plane, and CMY rendering means for performing rendering processing for each CMY plane after converting from CMYK to CMY and converting the output destination from CMY to CMYK. The drawing processing system according to claim 5.

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