JP2017081025A - Image processing device, image processing method of image processing device, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the width of a printed-out thin line visually uniform even in either of a thin line formed in a single color or a thin line formed in a mixed color.SOLUTION: An image processing device for processing inputted print information determines whether a thin line pixel generated from print information is a mixed color pixel in which a plurality of coloring materials are overlapped or a single color pixel in which a plurality of coloring materials are not overlapped. Here, a thickening amount to a thin line pixel is corrected between when the thin line pixel is determined to be a single color pixel and when the thin line pixel is determined to be a mixed color pixel, and thickening processing is performed to the thin line pixel according to the corrected thickening amount.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an image processing apparatus, an image processing method of the image processing apparatus, and a program.

  In general, there is a case where it is desired to change the line width or the like as a result of printing out the line drawing data created by CAD (Computer Assisted Drawing) software or the like. In such a case, conventionally, a print object is extracted from print data generated by an application, and attribute values and color information of the print object are acquired. Further, there is provided means for changing the color type / density and / or line width with respect to the monochromatic line and transmitting it to the printer device (for example, see Patent Document 1).

JP 2004-86639 A

  However, as a result of printing out a thin line composed of a single color having the same width (for example, 1 dot width) and a thin line composed of a mixed color on the image signal, both of them do not visually have the same width from the following principle. was there. Hereinafter, the problem will be described in detail with reference to FIG.

[First issue]
For example, when forming a monochromatic thin line with Magenta having a dot ratio of 100%, the result is as shown in FIG. A Magenta colorant 102 with a dot ratio of 100% is formed on the transfer belt 101 ((a-1) in FIG. 8). It is transferred and fixed on the paper, and the paper surface after printing is as shown in (a-2) of FIG.
On the other hand, for example, when forming a fine line (Red thin line) mixed in density with Magenta having a dot ratio of 100% and Cyan having a dot ratio of 100%, the result is as shown in FIG. A Magenta colorant 102 having a halftone dot ratio of 100% and a Cyan colorant 102 having a halftone dot ratio of 100% are overlapped to form the transfer belt 101 ((b-1) in FIG. 8).
It is transferred and fixed on the paper, and the paper surface after printing is as shown in (b-2) of FIG. Compared with (a-2) in FIG. 8, (b-2) in FIG. 8 is visually thick because the density is increased by the amount of cyan with a dot ratio of 100%.

[Second issue]
In addition, when there are multiple thin lines with the same width on the image signal that are composed of mixed colors, there is a problem in that both of them do not visually have the same width as a result of printing according to the color mixture ratio as a result of the following principle. It was.

  In the electrophotographic technology, when images having the same halftone dot ratio (for example, 100%) are formed, the amounts of colorants used for each of the colors Y, M, C, and K are different. For example, the amount of colorant necessary for forming an image of Yellow having a dot ratio of 100% is 0.3 mg, whereas Magenta is 0.4 mg and Cyan is 0.4 mg. The principle will be described on the assumption that the maximum load varies depending on the color.

  For example, when Cyan having a halftone dot ratio of 100% and Magenta having a halftone dot ratio of 100% are mixed, a total of 0.8 mg of colorant is transferred onto the belt under the above assumption. On the other hand, when Yellow having a halftone dot ratio of 100% and Magenta having a halftone dot ratio of 100% are mixed, a total of 0.7 mg of the colorant is transferred to the belt.

In this transfer process, when there is a large amount of colorant to be transferred, there is a phenomenon that the colorant scatters around. That is, when the amount of colorant to be used, that is, the maximum applied amount is large, the degree of scattering during transfer increases.
This is the principle that the thickness of the fine line changes depending on the color to be mixed. This principle also serves as a principle for explaining the first problem.

  The present invention has been made in order to solve the above-described problems, and the object of the present invention is to obtain a fine line that is printed out, whether it is a thin line composed of a single color or a thin line composed of a mixed color. Aim to provide a mechanism that can make the width visually uniform

The image processing apparatus of the present invention that achieves the above object has the following configuration.
An image processing apparatus for processing input print information, wherein a fine line pixel generated from the print information is a mixed color pixel in which a plurality of colorants overlap or a single color pixel in which a plurality of colorants do not overlap Correction means for correcting the fattening amount for the fine line pixel when the fine line pixel is judged to be a single color pixel, and when the fine line pixel is judged to be a mixed color pixel; Processing means for performing a fattening process on the thin line pixels in accordance with the thickening amount corrected by the correcting means.

  According to the present invention, it is possible to output a line drawing in which the thickness of a color thin line composed of a single color and a color thin line composed of a mixed color are not visually different.

1 is a diagram illustrating an image processing system including an image processing apparatus. It is a block diagram explaining the structure of an image processing apparatus. It is a figure which shows the specific example of an image process part. It is a flowchart explaining the data processing method of an image processing apparatus. It is a figure explaining the table which an image processing apparatus manages. It is a figure which shows the pattern table of a fattening process. It is a figure which shows the pattern table of a fattening process. It is a figure which shows the example of an image process. It is a figure explaining the subject of an image processing device.

Next, the best mode for carrying out the present invention will be described with reference to the drawings.
<Description of system configuration>
[First Embodiment]
FIG. 1 is a diagram illustrating an image processing system including an image processing apparatus according to the present embodiment.

  In FIG. 1, the image processing system 400 includes a network 401, a PC (personal computer) 402, printers 403 and 405, and a controller (RIP) 404. Printers 403 and 405 are examples of the image processing apparatus 200 described later. The PC 402 selects the printers 403 and 405 that the user wants to output. Then, a file (PDL file) created in the controller (RIP) 404 connected to the printer selected by the user or the PC (personal computer) 402 connected to the network 401 is transmitted to the printer 403.

FIG. 2 is a block diagram illustrating a configuration of the image processing apparatus illustrated in FIG.
In FIG. 2, the image processing apparatus 200 includes an image development unit 201 that processes input print information, an image data conversion unit 202, an image processing unit 203, and a printing unit 204. The image data conversion unit 202 includes an image memory 202A that stores the developed bitmap image.

  The image data conversion unit 202 generates image data constituting the screen based on the object list. Here, for example, line vector data is converted as raster data into printer resolution or bitmap data. The image data converter 202 generates and outputs attribute data corresponding to the bitmap data, for example, attribute data such as characters, graphics, and images. The image processing unit 203 performs a process of determining a thin line part (thin line pixel) for raster data converted into bitmap data, and switching a correction amount of the thin line correction process according to the number of colors constituting the thin line. The image data subjected to the fine line correction processing is sent to the printer unit 204, and an image is formed and output.

  The image processing unit 203 receives PDL file data generated by a PC or the like as described above, for example, data described in a PS file. The image development unit 201 interprets the contents of the PDL for the PDL file data, and generates an object list representing image information and character information constituting the image. This object list is a list indicating, for example, how many points and where the halftone dot percentage line is located. The transmitted file is subjected to image processing in each unit 201 to 203 shown in FIG. 2 in the controller or printer, and the transmitted PDL file is developed and output to the printing unit 204. The print unit 204 is configured to transfer a plurality of colorants (Y, M, C, K) to a sheet and obtain a color image.

FIG. 3 is a diagram illustrating a specific example of the image processing unit 203 illustrated in FIG.
In FIG. 3, the image processing unit 203 includes a color conversion processing unit 301, a color number determination processing unit 302, a fine line determination unit 303, and a thin line thickening unit 304. The fine line determination unit 303 extracts the fine line part by dividing the bitmap image for each color developed in the image memory 202A into the X direction and the Y direction, and performs the fine line determination process.

[Description of Image Processing Unit 203]
Processing for correcting mixed color and single-color fine lines in the image processing unit 203 will be described with reference to FIGS.
The image processing unit 203 receives PDL file data generated by a PC or the like as a video signal 300. In the color conversion processing unit 301, for example, RGB color signals are color-converted into CMYK signals and input to the thin line thickening unit 304 and the selector 305.
At the same time, the video signal after color conversion is also input to the color number determination processing unit 302. The color number determination processing unit 302 determines how many halftone dot ratios of Cyan, Magenta, Yellow, and Black are converted into CMYK, determines the number of colors used by the thin line, It is determined whether each color is a single color or a mixed color. The determined single color / mixed color information is input to the thin line thickening section 304 as determination information 306 such as “1” if the color is a single color and “0” if the color is a mixed color. For example, in the case of representing RED, it has information such as “C: 0%, M: 100%, Y: 100%, K: 0% color number flag: 0”.
In accordance with the flowchart shown in FIG. 5, the thin line thickening unit 304 determines the thickening correction amount, thickens the thin line, and inputs the video signal to the selector 305.

  In the selector 305, the video signal directly input from the color conversion processing unit 301 is adopted as output data or input from the thin line thickening unit 304 in accordance with the determination signal 307 as to whether or not the thin line is determined by the thin line determination unit 303. It is determined whether to use the video signal as output data.

  The fine line determination unit 303 may use line attribute information of the PDL command, or may determine how many pixels are connected in the horizontal direction (or vertical direction), and use the result as a thin line. . At least here, the determination signal 307 is a result of determining whether the line is a thin line and whether it is a horizontal direction or a vertical direction.

Next, the thin line thickening unit 304 will be described with reference to the flowchart shown in FIG.
FIG. 4 is a flowchart for explaining a data processing method of the image processing apparatus according to the present embodiment. Each step is realized by executing a control program stored in the CPU included in the image processing unit 203. Further, the image processing unit 203 may be provided with an ASIC that executes specific processing.
In step S <b> 501, based on the determination signal 306 input from the color number determination processing unit 302, it is determined whether the pixel to be processed is a single color pixel or a mixed color pixel. If it is a single color, the process proceeds to S502. If it is a mixed color, the process proceeds to S503.

Next, in S502, the thin line thickening correction amount in the case of a single color is determined based on the result of the halftone dot ratio. The thin line thickening correction amount in the case of a single color has a table as shown in FIG. This table is a table for instructing a thin line thickening correction pattern determined based on the maximum applied amount of toner (colorant) of each color (Y, M, C, K). More specifically, the table shown in FIG. 6A and FIG. 6B indicates the fattening pattern. It should be noted that the number of pixels of the correction amount for thickening each pattern is a table as shown in FIG.
As a feature of the tables in FIGS. 5A and 5B, based on the principle described in the second problem described above, a color with a small maximum toner amount is corrected more than other colors. On the contrary, the correction amount is also small for a color having a large amount and a large maximum toner loading amount.

On the other hand, if it is determined in S501 that the processing target pixel is a mixed color, a thin line thickening correction amount is determined in S503. Based on the same principle as S502 described above, a thickening pattern instruction to be used in S504 fattening processing is determined. FIG. 5B shows a table of the mixed color thin line thickening correction amount. Finally, in S504, the thin line thickening unit 304 performs a thin line thickening process.
Hereinafter, a specific method of processing in the thin line thickening unit 304 will be described with reference to FIG.

[Thin line thickening part]
The patterns thickened by the thin line thickening unit 304 are the patterns shown in FIGS. 6A and 6B. For example, when a thin line as shown in (b-1) of FIG. 7 is input and an output (battery result) as shown in (b-2) of FIG. 7 is obtained, it means that one pixel is thickened as a result. .
In addition, when the output (b-3) is as shown in FIG. 7B (thickening result), to add a pixel every other pixel, 1/2 pixel, that is, 0.5 pixel is increased (corrected). become.

Using the above configuration, the pixel to be processed is subjected to the fattening process using the fattening pattern information determined in S502 and S503.
For example, since the thickening pattern is “6” for a yellow monochromatic line with a dot ratio of 65%, the thickening processing result is as shown in FIG. When Yellow with a halftone dot ratio of 65% and Magenta with a halftone dot ratio of 55% are mixed in color, the fattening pattern for Yellow becomes “2”, and the fattening pattern for Magenta becomes “0”. Is as shown in FIG.

  The present invention supplies a program that realizes one or more functions of the above-described embodiments to a system or apparatus via a network or a storage medium, and one or more processors in a computer of the system or apparatus read and execute the program This process can be realized. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

203 Image processing unit

Claims (7)

An image processing apparatus for processing input print information,
Determination means for determining whether the fine line pixel generated from the print information is a mixed color pixel in which a plurality of colorants overlap or a single color pixel in which a plurality of colorants do not overlap;
Correction means for correcting the amount of thickening for the thin line pixel when it is determined that the thin line pixel is a single color pixel and when the thin line pixel is determined to be a mixed color pixel;
Processing means for performing a fattening process on the thin line pixels in accordance with the thickening amount corrected by the correction means;
An image processing apparatus comprising: The correction means includes
2. A first table that stores a pattern for thickening single-color thin line pixels and a second table that stores a pattern for thickening mixed-color thin line pixels. 3. Image processing apparatus.   The correcting means selects the first table when it is determined that the fine line pixel is a single color pixel, and selects the second table when it is determined that the thin line pixel is a mixed color pixel. The image processing apparatus according to claim 2.   The image processing apparatus according to claim 1, wherein the correction unit determines a fattening amount from a maximum loading amount of the colorant.   The image processing apparatus according to claim 1, wherein the correction unit determines the fattening amount from the number of colors to be mixed. An image processing method of an image processing apparatus for processing input print information,
A determination step of determining whether the thin line pixel generated from the print information is a mixed color pixel in which a plurality of colorants overlap or a single color pixel in which a plurality of colorants do not overlap;
A correction step of correcting a fattening amount for the fine line pixel when the fine line pixel is determined to be a single color pixel and when the fine line pixel is determined to be a mixed color pixel;
A processing step of performing a fattening process on the thin line pixel according to the thickening amount corrected in the correction step;
An image processing method for an image processing apparatus.   A program for causing a computer to execute the image processing method according to claim 6.

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