JP2750418B2 - Kabuse processing method at the boundary between line drawing and picture - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fogging processing method for creating a composite image while overlapping one another at a boundary between a color line drawing image and a color picture image.

[0002]

2. Description of the Related Art In the process of preparing a color printing plate, usually, printing plates of four colors (Y, M, C, K) are prepared.
Color prints are made by printing these printing plates on a four-color printing machine and overprinting four color inks. A color printing machine is a very precise machine. However, when actual printing is performed, even when a high-precision printing machine is used, a deviation of about ± 0.05 mm between the four printing plates (hereinafter referred to as “printing plate”). Misalignment "). Due to this misregistration, ink does not cover the portion where ink should be applied, and so-called “white spots” occur between print areas.
FIG. 25A shows a state in which white spots occur due to misregistration. The white spots are noticeable and cause the quality of the printed matter to deteriorate.

In order to prevent such a deterioration in quality, a process called "kabuse" is conventionally performed in the plate making process. The fogging process is a process of adjusting the shapes of two adjacent image regions so as to be in contact with each other and making the two overlap at the boundary. In the fogging processing, an additional area having a substantially constant width (hereinafter, referred to as a boundary) between the image areas.
(Referred to as a “cube region”). The color of the fogging area is determined so as to be as inconspicuous as possible during printing. FIG. 25B shows the result of misregistration in the case where the fogging region is formed. In this example, a fog area in which the M and C images overlap each other is formed. As a result, it can be seen that white spots did not occur even when printing misregistration occurred during printing.

It is necessary to form the fog region because the tendency of the density change across the boundary is different between different color plates (for example, the M plate and the C plate) as shown in FIG. This is the case when the direction is reversed. In the case of FIG. 25A, the density of the M plate is large outside the boundary and small inside the boundary, whereas the density of the C plate is large inside the boundary and small outside the boundary. On the other hand, as shown in FIG. 25C, in the case where the tendency of the density change is the same for different color printing plates, no remarkable white spots are generated due to the printing misregistration even if the fog region is not formed.

[0005]

In recent years, there have been proposed various methods for automatically performing the fog processing using an image processing apparatus (for example, Japanese Patent Application Laid-Open No. 4-58672).
However, the conventional fogging processing method is a method of performing fogging processing at a boundary between line drawing images such as tint (flat screen) or a picture image, and automatically performs the fogging processing at a boundary between the line drawing image and the picture image. There was no known way to do this. One reason for this is that the line drawing image data and the picture image data have different resolutions, so that it is difficult to form a fog region between them with an appropriate resolution.
Further, the difference between the formats of the line drawing image data and the picture image data also causes the formation of the fog region to be difficult. Further, since the color of the picture image changes for each pixel, it has been difficult to determine the color of the overlapping area at the boundary with the line drawing image.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem in the prior art, and has as its object to provide a method for performing a fog processing at a boundary between a line drawing image and a picture image.

[0007]

In order to solve the above-mentioned problems, a first kabuse processing method according to the present invention comprises: (a) preparing picture image data representing a plurality of color components of a picture image at a first resolution; (B) line drawing expression data representing a plurality of color components of the line drawing image at a second resolution higher than the first resolution, and any of the pattern image and the line drawing image for each pixel of the line drawing image. Preparing line drawing image data including priority data indicating whether priority is given; (c)
At the boundary between the line drawing image and the picture image, a fog direction indicating whether a fog area is formed on the line drawing image side or on the picture image side is designated, and a color component of the line drawing image to be adopted in the fog area is specified. (D) forming at a second resolution a fog area having a predetermined width extending in the fog direction from a boundary between the line drawing image and the picture image; and (e) the fog area. , The color components of the type specified in the step (c) are given priority to the line drawing image, and the color components other than the type specified in the step (c) are given priority to the picture image. Updating the priority data so as to indicate that the line drawing expression data has a resolution equal to or higher than the second resolution while referring to the updated priority data. And a step of creating a composite image by combining the serial picture image data.

Further, the second fogging processing method according to the present invention comprises: (a) a step of preparing picture image data representing a plurality of color components of the picture image at a first resolution; and (b) a plurality of picture image data of the line drawing image. A line drawing including line drawing expression data representing a color component at a second resolution higher than the first resolution, and priority data indicating which of the picture image and the line drawing image is given priority for each pixel of the line drawing image Preparing image data; (c) forming a fuzzy candidate area of a predetermined width at the second resolution at a boundary between the line drawing image and the picture image; The density of each color component of the line drawing image and the pattern image is compared for each pixel, and the density of the line drawing image is higher than the density of the pattern image.
The color component larger than a predetermined amount and the density of the pattern image
Color components larger than the density of the line drawing image by a predetermined amount or more are mixed
If the color image density is higher than the density of the picture image by a predetermined amount or more, priority is given to the line image, and the density of the pattern image is higher than the density of the line image. Updating the priority data so as to indicate that the picture image is prioritized for a color component larger than a predetermined amount; and (e) referring to the updated priority data at a resolution higher than the second resolution. Creating a synthesized image by synthesizing the line drawing expression data and the picture image data.

[0009]

In the first fog processing method, the fog direction indicating the direction in which the fog area is formed and the color component of the line drawing image adopted in the fog area are specified in advance, so that the desired color is placed on the desired side of the boundary. A fog region of the component can be formed. Also, priority data indicating which of the line drawing image and the pattern image is prioritized in the fog region is created with the resolution of the line drawing image. By synthesizing the image and the image, it is possible to create a synthesized image including the fog region.

In the second fog processing method, a fog candidate region is formed at the boundary with the resolution of the line drawing image, and a line drawing image and a pattern image are formed for each pixel of the fog candidate region for a color component having a difference of a predetermined amount or more in density. Priority data is created indicating that is superimposed. Then, by referring to the priority data, a composite image including the fog region is created by synthesizing the line image and the pattern image with a resolution higher than the resolution of the line image, so that the operator can superimpose the color in the fog direction and the fog region. The fog region can be formed without specifying the components.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Configuration of Apparatus FIG. 1 is a conceptual diagram showing the overall configuration of a plate making system for performing a fogging process on an image by applying an embodiment of the present invention.
The plate making system includes a flat scanner 100, a color separation scanner 200, an image processing device 300, and a recording scanner 400.

The flat scanner 100 reads a line drawing image (hereinafter, simply referred to as "line drawing") including characters, ruled lines, illustrations, logos, and the like, and creates line drawing data by compressing the obtained image data into run-length data. Device. The resolution (pixel density) of the flat scanner 100 is, for example, 2000
dpi. The color separation scanner 200 is an apparatus that obtains picture data by reading a picture image such as a photograph (hereinafter simply referred to as “picture”) as bitmap data. The resolution of the color separation scanner 200 is, for example, 400 dpi. In this embodiment, the resolution of the picture data (400
dpi) is 1/5 of the resolution (2000 dpi) of the line drawing data.

The image processing apparatus 300 performs correction processing such as pinhole removal and coloring (processing for coloring a desired area) on the line drawing data, and performs correction processing such as color correction and erasure on the picture data. When the operator determines the position where the picture is pasted on the line drawing, the position data is registered in the memory as a picture offset described later. The corrected line drawing data also includes a pattern priority flag indicating that the pattern data is combined with the line drawing data in a region where the pattern is pasted. The recording scanner 400 combines the corrected line drawing data and the corrected pattern data, and records the combined image on the photosensitive film PF as a mesh image.
The halftone image is created for each color plane of Y (yellow), M (magenta), C (cyan), and K (black), for example.

FIG. 2 is a block diagram showing the internal configuration of the image processing apparatus 300. The image processing apparatus 300 includes the following components. (A) CPU 302: controls each part of the image processing apparatus and performs image processing on line drawing data and picture data. The CPU 302 and components described below are interconnected via a bus 304. (B) ROM 306: a memory for storing a processing program executed by the CPU 302. (C) RAM 308: a memory for temporarily storing various data used for image processing, and in particular, various parameters (image data size, picture offset, fog processing mode (described later)) and color described later. Remember the palette. The color palette is a table showing the correspondence between the color numbers assigned to the image areas of the line drawing and the color data (dot area ratio) of each color plane. (D) Line memory 310: a memory for storing image data necessary for processing when performing thickening processing or thinning processing of line image data.

(E) Line drawing memory 312: A memory for storing image data representing line drawings before and after image processing. CPU 30
Reference numeral 2 uses the line drawing memory 312 to execute image processing such as thickening processing, thinning processing, coloring processing, thinning processing, and enlargement processing. The line drawing memory 312 has a plurality of memory planes that can store one page of image data. At the time of image processing, it is necessary to store the source image (image before processing) and the destination image (image after processing),
At least two memory planes are used. (F) Picture memory 314: A memory for storing picture data in a bitmap format, and stores data of a plurality of picture parts to be pasted on an image of one page and picture data of one page for output. The picture memory 314 also has a plurality of memory planes. (G) Keyboard I / O interface 316: an interface for receiving input from the keyboard 318 and the mouse 320. (H) Display control unit 322: color image CRT3
An interface used when displaying images by transferring them to H.24. When displaying a line drawing on the CRT 324, the CPU
After the line drawing data 302 is thinned out, bitmap expansion is performed to create bitmap data of a thinned image, and this data is transferred to the display control unit 322. (I) Interface for inputting image data 326: An interface for receiving image data supplied from the flatbed scanner 100 or the color separation scanner 200, or transferring picture data or line drawing data to the recording scanner 400.

B. Outline of Processing Procedure FIG. 3 is a flowchart showing a procedure of a plate making process for performing a fogging process by applying an embodiment of the present invention. In step S1, line drawing data is read using the flat scanner 100, and in step S2, picture data is read using the color separation scanner 200. When a plurality of picture components are used, image data for each picture component is read.
In steps S3 and S4, the line processing data and the pattern data are processed using the image processing apparatus 300. That is, processing such as pinhole removal, coloring, and fogging processing between line drawings is performed on line drawing data, and processing such as color correction and scratch removal is performed on picture data. The offset of each picture component is registered in the RAM 308 as a parameter.

FIG. 4A shows a line drawing to be processed, FIG. 4B shows a picture, and FIG. 4C shows an integrated image obtained by synthesizing them. Note that these images are those before the fogging processing. The line drawing in FIG. 4A includes a first region R1 which is a tint region, and a second region where a pattern is pasted.
And a third region R3 which is a tint region. Color numbers # 1, # 2, and # 3 are assigned to the regions R1, R2, and R3, respectively. Note that line drawings generally include characters, logos, illustrations, and the like, but for the sake of simplicity, a case where the above-described line drawings are processed will be described.

FIG. 5 is an explanatory diagram showing the structure of line drawing data. As shown in FIG. 5A, the linework data includes a linework data management unit, a color palette unit, and a run length data unit. The line drawing data management unit includes data such as the size, resolution, and file name of the line drawing.

As shown in FIGS. 5B and 5C, the color palette section stores information corresponding to each color number.
The dot area ratio (dot%) of each color plate and the pattern priority flag Fy,
Fm, Fc, and Fk. For the color plate with the pattern priority flag of 1, the pattern data has priority, and for the color plate with the pattern priority flag of 0, the line drawing data has priority. Data of the color palette section (hereinafter, simply referred to as “color palette”) is stored in the RAM 308 (FIG. 2).

FIG. 6 shows the correspondence between the color numbers represented by the color palette CP and the dot area ratios of the respective color plates. For example, for the color number # 1 of the region R1, the halftone dot area ratio of magenta is 100%, and the halftone dot area ratios of the other three plates are 0%. The color plate in which “I” is registered in the color palette CP indicates that the value of the pattern priority flag is “1”. That is, in the color number # 2 for the region R2 in FIG. 4A, the picture data is adopted in preference to the line drawing data for all the color plates.

The run length data section includes the run length data shown in FIG. One unit of run-length data (hereinafter, referred to as “unit run-length data”) is generated for each run of the line drawing (FIG. 4A).
It contains run length and color number. FIG. 5D shows run-length data along the scanning line L1 in FIG. 4A, in which run lengths and color numbers of the regions R1, R2, and R3 are registered in each unit run-length data. .
Such run-length data is stored in the line drawing memory 312.

FIG. 7 is a conceptual diagram showing the structure of picture data. FIG. 7A shows picture data for one pixel including data representing the dot area ratio of each of YMCK. FIG. 7B shows a pixel array of picture data on the image plane. That is, pixels are arranged in a scanning line sequence along the main scanning direction Y, and FIG.
The data of (A) is stored in the picture memory 314.

Returning to FIG. 3, in step S5, the line drawing and the pattern are displayed on the CRT 324 so that the operator determines the position of the pattern. FIG. 4B shows a state where the picture is positioned on an image plane having the same size as the line drawing.
The picture offset is the position coordinates (xp, yp) of the picture origin OP based on the origin OL of the image plane. This offset is stored in the RAM 308.

In step S6, the operator inputs a fog processing parameter. The fogging processing parameters include a fogging width, a fogging target exclusion color, and a fogging mode. The edge width is the width of the edge region formed at the boundary between the picture and the line drawing, and is specified by the number of pixels. A value of about 7 pixels is specified as the value of the fog width at a resolution of 2000 dpi. The exclusion target color is a color plane in which the density value of the original line image is stored in the obscuration area.
On the other hand, as will be described later, for a color plate that is not a color subject to fogging, the density value of the pattern is adopted in preference to the line drawing.

The fog mode is a mode indicating the fog direction, and includes the following three modes. Outer mode: A fog area is formed on the side of the line drawing from the boundary between the line drawing and the picture. The outer mode is applied when the density of the picture at the boundary is lower than that of the line drawing. Inner mode: A fog area is formed on the side of the pattern from the boundary between the line drawing and the pattern. The inner mode is applied when the density of the line drawing at the boundary is lower than the pattern. Auto mode: A fog area is formed around the boundary according to the magnitude relationship between the density of the line drawing and the color plate of the picture at the boundary.
The auto mode can be applied irrespective of the magnitude relationship between the density of a line drawing and a pattern at a boundary.

The details of each processing parameter will be described later. For the picture parts for which no fogging processing is performed, it is specified in step S6 that no fogging processing is performed. The necessity of the overlap processing, the overlap mode, and the overlap width are stored in the RAM 308 as overlap processing parameters.

If there is a plurality of picture parts to be pasted in the image of one page, the process returns from step S7 to step S5, and repeats steps S5 and S6. In this embodiment, for the sake of simplicity, a case in which there is one picture component will be described. When the position of the picture parts and the specification of the fog processing parameters are completed,
In step S8, the fogging process is performed by the image processing device 300. In this fogging process, a fog area is formed at the boundary between the picture and the line drawing, and processed line drawing data and processed picture data to be supplied to the recording scanner 400 are created. Details of the fogging process will be described later.

In step S9, the recording scanner 400 combines the processed line drawing data and picture data to create a halftone image of the integrated image. The halftone image is a color separation image of an integrated image including a fog region, and is usually a YMCK 4
One halftone image is created. FIG. 8 shows the recording scanner 4.
It is a block diagram which shows schematic structure of 00. The run-length data input to the recording scanner 400 is stored in a run-length memory 402, and the picture data is stored in a picture memory 4.
04 is stored. The encoder 432 provided on the recording drum 430 generates a reference clock signal Sck synchronized with the rotation of the recording drum 430, and supplies the reference clock signal Sck to the read address / clock generation circuit 410. The read address / clock generation circuit 410 generates a clock signal Sbk to be applied to the bitmap development circuit 408 and a line image read address Aw to be applied to the run-length memory 402.
Read address Ap to be given to the picture memory 404
Occurs.

Here, the correspondence between line drawing and picture pattern pixels will be described. FIG. 9 is an explanatory diagram showing a comparison between the sizes of the pixels of the line drawing and the picture. The length of one side of the line drawing pixel Pw is １ ／ of the length of one side of the picture pixel Pp. That is,
The resolution of the line drawing is five times the resolution of the picture. The picture data is read from the picture memory 404 at the same resolution as the line drawing data. That is, the run length memories 402 to 5
While the run length data for the scanning line is read, the picture data for one scanning line is read from the picture memory 404. While the run-length data of five pixels on one scanning line is developed by the bitmap development circuit 408, the same picture data of one pixel is read from the picture memory 404 five times. As a result, the image data of one pixel of the picture is read 25 times in synchronization with the creation of the bitmap data of 5 × 5 pixels of the line drawing.

The bitmap developing circuit 408 is a circuit for converting the run-length data into data for each pixel based on the run-length data and the contents of the color palette. The bitmap-developed line drawing data has the same configuration as the picture data shown in FIG. The bitmap development circuit 408 outputs a picture priority signal Sf together with the line drawing data Db after bitmap development (hereinafter, simply referred to as “bitmap data”). Picture priority signal S
f is a picture priority flag Fy, Fm, F shown in FIG.
It is a signal representing c and Fk.

The picture priority signal Sf is inverted and the first AN
D gate unit 412, and bitmap data Db is directly input to first AND gate unit 4
12 is input. This AND gate unit 412
Is a circuit including the same number of AND gates as the number of bits (= 8) of one color plane of the bitmap data Db, but is simplified in FIG. 8 for convenience of illustration.
When the value of the picture priority signal Sf is 1 (that is, when the picture data is prioritized), the first AND gate unit 412
Is always 0. On the other hand, when the value of the picture priority signal Sf is 0, the bitmap data Db is the output of the first AND gate unit 412.

The picture priority signal Sf is also supplied to the second AND gate unit 414 together with the picture data Dp. When the value of the picture priority signal Sf is 1, the picture data Dp
Is the output of the first AND gate unit 414. When the value of the picture priority signal Sf is 0, the output of the second AND gate unit 414 is always 0.

First and second AND gates 412, 414
Is input to the OR gate unit 416. That is, depending on the value of the picture priority signal Sf, the OR gate unit 416 stores the bitmap data Db of the line drawing or
Alternatively, one of the picture data Dp is input.
The output of the OR gate unit 416 is supplied to a halftone signal generation circuit 418, and a halftone signal Dd indicating the presence or absence of exposure is generated for each pixel. The exposure head 420 generates a laser beam modulated according to the halftone dot signal Dd, whereby a halftone image is recorded on the photosensitive film PF mounted on the recording drum 430.

The method and apparatus for synthesizing the line drawing data and the picture data are disclosed in Japanese Patent Publication No. 2-44544, Japanese Patent Publication No. 1-23032, and Japanese Patent Publication No. 2-201994 disclosed by the present applicant. It is also possible to use what is described in detail. In the circuit of FIG.
Represents the bitmap data Db of the line drawing at the resolution of the line drawing and the picture
The pattern data Dp was combined with the pattern data Dp.
It is possible to carry out with a resolution higher than the resolution.

C. FIG. 10 is a flowchart showing a detailed procedure of the fogging process in step S8 of FIG. In step S21, it is determined whether or not there remains any picture parts to be pasted. If there is a picture part to be pasted, in step S22, the fogging processing parameter in the RAM 308 is checked, and it is determined whether or not the fogging processing is designated for the picture part. Here, first, the case in which the overlap processing is not performed will be described, and then, the processing procedure in each of the outer, inner, and auto overlap modes will be described.

C-1. When no fogging processing is performed When no fogging processing is performed, the process proceeds from step S22 to step S26 in FIG. 10, where mask line drawing data is created. FIG. 11 is an explanatory diagram showing the procedure of the processing when the overlapping processing is not performed. FIG.
FIG. 4A shows the line drawing shown in FIG. FIG.
In (A), the dot area ratio of each of the regions R1, R2, and R3 is Y.
/ M / C / K. However, "I"
Indicates that the picture priority flag is 1. The value of the dot area ratio corresponds to the value represented by the color palette CP in FIG.

In step S26, a 1 / N priority thinning process relating to the picture priority flag "I" is performed on the line drawing data shown in FIG.
Is formed. FIG. 12A shows an example of an image before the priority thinning processing, and FIG. 12B shows an image after the priority thinning processing. In FIG. 12, a hatched portion is a region R3 in FIG. 11A, and a region without the hatched portion is a picture region R2. In the priority thinning process, N
If at least one pixel of the picture priority flag is 1 in the × N pixel block, the picture priority flag of the representative pixel representing the pixel block becomes 1. In the example of FIG. 12, the ratio of the resolution between the line drawing and the picture (= 5) is adopted as the value of N. In FIG. 12B, a pixel indicated by a sand background is a representative pixel corresponding to a pixel block in which a pixel with a pattern priority flag of 1 and a pixel with a pattern priority flag of 0 are mixed in a line drawing before the thinning processing. . The value of the picture priority flag of such a representative pixel is also 1.

FIG. 11B shows a mask line drawing represented by mask line drawing data obtained by the priority thinning process. The size Wx / N, Wy / N of the mask line drawing expressed by the number of pixels is 1 / N of the size Wx, Wy of the original line drawing. However, in the mask line drawing data of FIG. 11B, the halftone dot area ratios of the areas where the value of the picture priority flag is not 1 are all replaced with 0. The reason for this is that the mask line drawing is used for masking a pattern, so that data other than the pattern priority flag is unnecessary. The mask line drawing data is stored in the line drawing memory 312. Since the priority thinning process is described in detail in Japanese Patent Application Laid-Open No. 4-134570 disclosed by the present applicant, the details are omitted here.

Returning to FIG. 10, in step S27, the CP
U302 a picture is pasted in the picture area of the mask line drawing.
In the case of pasting a plurality of pictures, first, the first pictures are pasted on the plane of the blank output picture image, and then the pictures are pasted sequentially. At this time, if a pattern is cut out and pasted into a desired shape using a mask line drawing, when the patterns are overlapped or when the boundaries between the patterns are in contact with each other, the boundary portion is desired. Can be formed.

FIG. 11D shows a pattern pasted on the plane of the image, and the pattern data representing the entire image is processed pattern data. The pattern in FIG. 11D has the same size as the mask image. Note that the picture is offset (xp, y) specified in step S5 (FIG. 3).
It is pasted at the position of p). The pasted output pattern image is stored in the pattern memory 314.

When the picture is pasted, the mask line drawing data is deleted from the line drawing memory 312 in step S28. When there is one picture part, the output picture image data of FIG. 11D and the line drawing data of FIG. 11A are supplied as processed image data from the image processing apparatus 300 to the recording scanner 400. An integrated image shown in (E) is obtained. When there is only one pattern and there is no overlap between the patterns as shown in FIG.
An integrated image shown in FIG. 11E may be generated from the picture data shown in FIG. 11C and the line drawing data shown in FIG.

When a plurality of picture parts are pasted, 1
After one picture component is pasted, the process returns from step S28 to step S21, and returns to step S21 for the next picture component.
The processing of 21 to S28 is repeated. Prior to the above processing, the border area between the line drawing area R1 and the line drawing area R3 is subjected to the normal fogging processing as described in step S3 in FIG. 3, but this processing is an object of the present invention. It is not explained because it is outside. The same holds true prior to performing the three types of fogging processing described later.

C-2. Outer Mode Fog Processing When performing outer mode fog processing, FIG.
Step S24 is performed through steps S21, S22, and S23 in the procedure described above. In step S24, a thickening process is performed in the designated fog direction to form a fog region. FIG. 13 is an explanatory diagram showing the procedure of the fogging process in the outer mode.

In step S24, the thickening process or the thinning process of the picture region R2 is executed in accordance with the fog processing parameter designated in step S6 (FIG. 2).
That is, in the case of the outer mode, a thickening process is performed to expand the picture region in the line drawing by the overlap width, and in the inner mode, a thinning process is performed and the picture region contracts by the overlap width ( The thinning process and the thickening process are common methods, and description thereof is omitted in this specification. This fattening process or thinning process is executed using eight neighboring pixels or four neighboring pixels centered on the target pixel. FIG.
When the pattern area thickening process is performed on the line drawing of (A), an image of FIG. 13B is obtained, and a new boundary BR2 indicated by a broken line is shifted from the original boundary BR1 indicated by a solid line to the line drawing region R.
1, formed on the side toward R3. As a result, new regions R4 and R5 are formed between the two boundaries BR1 and BR2. These regions R4 and R5 are a fog region.

FIG. 14 is an explanatory diagram showing a method of determining the color data of the fog regions R4 and R5 formed in step S24. FIG. 14A shows the color data around the boundary BR1 in the line drawing before the thickening process of the picture area, and FIG. 14C is a plan view corresponding thereto. FIG.
4 (B) shows the color data of the overlapping area R4, and FIG. 14 (D) is a plan view corresponding thereto. FIG.
As shown in (B), Y / M / C / K of the fog region R4
Is I / I / 100/0 (I indicates that the picture priority flag is 1). Cyan (C) and black (K) are designated as the exclusion target colors. That is, the halftone dot area ratios of the excluded colors C and K are used directly in the overlapping regions R4 and R5. On the other hand, for the color plates Y and M which are not the color to be excluded, the pattern priority flag “I” is set in the fog regions R4 and R5, and the pattern data is prioritized. FIG. 14 (E)
Indicates a color palette CP including the color numbers C4 and C5 of the fog regions R4 and R5.

As can be seen from FIG. 14B, the line drawing areas R1 and R3 and the picture area R for the color C and K to be excluded are not used.
2 is the original boundary BR1. Therefore, for the fog removal exclusion colors C and K, the high resolution edges of the line drawing regions R1 and R2 in the original line drawing are maintained. On the other hand, with respect to the color plates Y and M other than the color to be subjected to fogging, the pattern data is prioritized in the fog regions R4 and R5.
As a result, in the overlapping areas R4 and R5, the line drawing and the pattern are recorded in a state where they overlap each other.

The color to be excluded for the fog is 4 for YMCK.
Three or fewer numbers are specified from among the color plates. As the exclusion target color, a color plate having a high density in the line drawing regions R1 and R2 near the boundary BR1 and conspicuous is selected. In this way, the high resolution edges of the conspicuous color plate can be preserved. In step S24, a fog area is formed only between the area where all the pattern priority flags of the four-color version are 1 and the area where all the pattern priority flags of the four-color version are 0. This is because the region where the color priority of the pattern priority flag is 1 and the color plate of the color 0 are mixed is the fogging area formed by the fogging processing executed previously, and it is necessary to further form the fogging area in this area. Because there is no.

Returning to FIG. 10, after the fog region is formed in the line drawing in step S24, the process proceeds to step S26.
Steps S26 to S28 described above are performed. In step S26, as shown in FIG. 13C, priority thinning processing is performed on a line drawing including a fog region. The mask area in the mask line drawing obtained as a result (the area where the pattern priority flags of all the color plates are 1) has a shape that includes the pattern area R2 and the fog areas R4 and R5.

In step S27, a pattern is pasted using the mask line drawing of FIG. 13C to obtain an output pattern image of FIG. 13E, and in step S28, the mask line drawing data is erased. The output line drawing data of FIG. 13B and the output picture data of FIG.
0, and the integrated image shown in FIG. 13F is recorded (step S9).

C-2. Fogging Process in Inner Mode FIG. 15 is an explanatory diagram showing the procedure of the fogging process in the inner mode. In the inner mode, a thinning process is performed on the picture area in step S24 of FIG. When the pattern region thinning process is performed on the line drawing of FIG. 15A, a line drawing of FIG. 15B is obtained, and the line drawing from the original boundary BR11 indicated by the solid line toward the pattern region R12 is:
A new boundary BR12 indicated by a broken line is formed. As a result, the overlap region R is located between the two borders BR11 and BR12.
14, R15 are formed.

FIG. 16 is an explanatory diagram showing a method of determining the color data of the overlapping areas R14 and R15 formed in step S24. FIG. 16A shows color data around the boundary BR11 in the line drawing before the thinning process, and FIG. 16C is a plan view corresponding to this. FIG.
FIG. 16B shows the color data of the overlapping area R14, and FIG. 16D is a plan view corresponding thereto. FIG.
As shown in (B), Y / M / C /
The color data of K is 0/100 / I / I (I indicates that the picture priority flag is 1). Also at this time, cyan (C) and black (K) are designated as the exclusion target colors. FIG. 16E shows the overlapping region R14, R1.
5 shows a color palette CP including five color numbers C14 and C15.

In the inner mode, as in the case of the outer mode, the high-resolution edges of the line drawing regions R11 and R12 in the original line drawing are maintained for the color to be excluded. A color plate having a high density in the picture area near the boundary BR11 and conspicuous is selected as the exclusion target color. The other processes in the inner mode are the same as those in the outer mode.

C-3. Fogging Process in Auto Mode FIG. 17 is an explanatory diagram showing how a fuzz region is formed in the auto mode. In FIG. 17A, C
In the plate, the line drawing is stronger than the pattern, and in the Y and M versions, the pattern is stronger than the line drawing. In this embodiment, when the difference between the halftone dot area ratios of the line drawing and the picture is less than 20%, it is considered that the halftone dot area ratios of the line drawing and the picture are almost equal. When a color plate with a strong line drawing and a color plate with a strong design are mixed as in the example of FIG. 17A, a fog region is formed at the boundary as shown in FIG. 17B. Then, the halftone dot area ratio of the image determined to be strong is adopted as the halftone dot area ratio of each plate of the fog region. That is, in the example of FIG. 17B, the halftone dot area ratio of the line drawing is adopted for the C plate, and the halftone dot area ratio of the picture is adopted for the Y plate and the M plate. Here, regarding this strength judgment, if the range considered to be substantially equal to the above is reduced,
The density of the fogged area of the finished image is necessarily increased. Therefore, this range is set to less than 20% in this example, but may be set by appropriately changing it empirically in accordance with actual work. Further, it may be changed for each color plate. Either halftone area ratio may be adopted for a color plate in which the halftone area ratios of both images are determined to be substantially equal. FIG. 17C shows line drawing data for forming the image of FIG. 17B. In FIG. 17C, the pattern priority flag of the color plate in which the pattern is prioritized is “1”. In the fogging process, only the line drawing data is processed, so that the picture data remains as it is, as shown in FIG.

FIG. 18 is an explanatory diagram showing a case where no fogging region is formed in the auto mode. FIG.
(A) is a case where the difference between the halftone dot area ratios of the line drawing and the picture is less than 20% in any color plate, and is considered to be substantially equal. In this case, no fog region is formed. This is because, as shown in FIG. 25 (C), when the tendency of the density change across the boundary is almost the same between color plates, even if a fog region is not formed, a marked white spot due to plate misregistration occurs. It will not occur.

For the same reason, FIG. 18C and FIG.
In the case shown in (E), it is not necessary to form the fog region.
FIG. 18C shows a case where the C version has a strong line drawing, but the other versions have substantially the same line drawing and pattern. Also in this case, the fog region need not be formed. FIG. 18E shows a case where the M and C versions have a strong pattern, but the other versions have almost the same line drawing and pattern. Also in this case, the fog region need not be formed. In each of the cases of FIGS. 18A, 18C and 18E, no fog region is formed, and accordingly, FIGS.
As shown in (D) and (F), the line drawing data is not changed by the fog processing.

Next, the processing procedure in the auto mode will be described. When auto mode is specified,
The process proceeds from step S23 of step S23 to step S25, where a fog region is formed as necessary. FIG. 19 is a flowchart showing a detailed procedure of step S25.
20 to 22 are explanatory diagrams showing the processing contents in the procedure of FIG.

In step S31, the boundary BR1 between the picture region R2 and the line drawing regions R1 and R3 in the line drawing in FIG.
Then, regions R21 and R22 having a width of one pixel (hereinafter, referred to as “boundary regions”) are formed, and a line drawing shown in FIG. 20B is obtained. The boundary regions R21 and R22 are formed closer to the line drawing regions R1 and R2 than the boundary BR1. Note that the boundary region R2
1 and R22 are formed by thickening the picture region R2 using four neighboring pixels or eight neighboring pixels as described above. The boundary regions R21 and R22 correspond to the fog candidate regions in the present invention.

In step S31, the boundary region R2
1, color numbers # (x + 1) and # (x + 2) for R22
Are assigned, and the color palette CP in the RAM 308 is assigned.
Registered in. Here, x is an arbitrary numerical value equal to or larger than the maximum value of the unused color numbers, and these color numbers #
The halftone dot area ratio of each color plate corresponding to (x + 1) and # (x + 2) may be an arbitrary value (for example, 0). At this time, FIG.
A color number correspondence table CCT1 shown in FIG. 0 (E) is created and registered in the RAM 308. The color number correspondence table CCT includes a new color number # for the boundary areas R21 and R22.
Table showing the correspondence between (x + 1), # (x + 2) (hereinafter, referred to as “boundary color number”) and the color numbers of regions R21, R22 in the original line drawing (hereinafter, referred to as “original color number”) It is. In step S31, only the area where all the pattern priority flags of the four-color version are 1 and the area where all the pattern priority flags of the four-color version are 0 are set.
A new area is formed. The reason for this is that the region where the color plate with the pattern priority flag of 1 and the color plate with the value of 0 are mixed is a fog area, and it is not necessary to form a fog area in this area.

In step S32, a 1 / N priority thinning process for the boundary color number is executed. That is, N × N
If at least one pixel having a boundary color number exists in the pixel block, the boundary color number is adopted as the color number of the representative pixel representing the pixel block. FIG. 20C shows the line drawing thus obtained. In the run-length data representing the line drawing of FIG.
1 and R22 have boundary color number # (x
+1) and # (x + 2) are registered.

In step S33, for each pixel in the boundary regions R21 and R22 in FIG. 20C, the halftone dot area ratio of each color plane designated by the original color number and the corresponding pattern (FIG.
(F)) is compared with the halftone dot area ratio of each color plate, and the color numbers of the boundary regions R21 and R22 are updated according to the comparison result. FIG. 23 is a flowchart showing the detailed procedure of step S33.

In step S41, one pixel included in the boundary regions R21 and R22 in the line drawing of FIG. 20C is selected as a pixel to be processed. In step S42, first, the original color number in the table is read out with reference to the color number correspondence table CCT (FIG. 20E) according to the boundary number of the pixel to be processed. For example, for the boundary region R21, the original color number # 1 corresponding to the boundary color number # (x + 1) is read. Next, the dot area ratio of each color plate corresponding to the original color number is read from the color palette CP. The halftone dot area ratio corresponding to the original color number # 1 in the boundary region R21 is 0/0/100/0 (Y / M / C / K) as shown in FIG.

In step S43, the halftone dot area ratio of each color plate is read from the picture data (FIG. 20 (F)) for the pixels on the picture corresponding to the pixels to be processed. In step S44, the halftone dot area ratio of the line drawing and the halftone dot area ratio of the picture are compared for each color plate with respect to the pixel to be processed, and the strength relationship is determined. FIG. 24 is an explanatory diagram showing the processing content of step S44.

FIG. 24A shows the halftone dot area ratio of the line drawing at the pixel to be processed, and FIG. 24B shows the halftone dot area ratio of the picture at the pixel to be processed. These halftone dot area ratios are compared for each color plate, and a strength determination table shown in FIG. 24C is created. The strength determination table determines the strength of a line drawing as follows according to the relationship between the dot area ratio of a line drawing and the dot area ratio of a picture. 20 (%) <RL-RP: strong 20 (%) <RP-RL: weak | RL-RP | ≦ 20 (%): equal where RL is the dot area ratio of the line drawing, and RP is the dot of the picture. The area ratio. That is, if the dot area ratio of the line drawing or the dot area ratio of the picture is 20% or more, it is determined that the line drawing is strong. Conversely, the dot area ratio of the picture or the dot area ratio of the line drawing is 20%. If it is greater than%, the line drawing is determined to be weak. When the difference between the two is not more than 20%, it is determined that the two have the same strength. The value of the halftone dot area ratio serving as the criterion may be set to a different value for each color plate.

In step S45, the dot area ratio of the pixel to be processed is determined according to the strength determination table, and a new color number is set as necessary. The dot area ratio of the processing target pixel is determined as follows. 1) When “strong” and “weak” are mixed in the strength determination table This is the case corresponding to FIG. In this case, the halftone dot area ratio of the line drawing is adopted for the “strong” color plate, and the picture priority flag is set to 1 for the “weak” or “equal” color plate. 2) When the four color plates in the strength judgment table are "strong" or "equal", and when they are "weak" or "equal" (that is, when "strong" and "weak" are not mixed) This is the case corresponding to one of FIGS. 18 (A), (C) and (E). In this case, the fogging process is not substantially executed. That is, the original color number is adopted as the color number of the pixel to be processed.

Since the condition of the above 1) is applied to the strength judgment table of FIG. 24C, the pixel to be processed is a pixel in the fog region. For this processing target pixel, a boundary color correspondence table BCT shown in FIG. 24D is created. In the table BCT, the halftone dot area ratio (100%) of the line drawing is adopted for the color plate C which is “strong” in the strength judgment table, and for the other color plates Y, M, and K. Indicates that the picture priority flag is 1. Since the combination of the halftone dot area ratios of each color plate is not registered in the color palette, a new boundary color number # (x + 3) is assigned. On the other hand, for the processing target pixel that satisfies the above condition 2), the boundary color number is converted to the original color number, and does not become a fog area.

In step S46 of FIG.
Steps S41 to S45 for all pixels 21 and R22
It is determined whether or not the process has ended, and if not, steps S41 to S45 are repeated. As a result, the line drawing of FIG. 20D is obtained. In the line drawing of FIG. 20D, the boundary color number changes from # (x + 1) to # (x + 3) in a part of the boundary region R21 of the line drawing of FIG. 20C. The pixel having the changed boundary color number # (x + 3) has the original boundary color number # (x + 3) while the color plate with the picture priority flag of 1 exists as shown in FIG.
Pixels having 1) and # (x + 2) all have the picture priority flag of 0.

Returning to FIG. 19, in step S34, FIG.
The pixel density of the line drawing data of 0 (D) is simply multiplied by N to make the resolution the same as that of the original line drawing (FIG. 20A). As a result, the line drawing of FIG. 21A is obtained. In step S35, the boundary color number of the line drawing in FIG. 21A is set as the color number of each pixel in the boundary regions R21 and R22 in the line drawing in FIG. By adopting, the line drawing of FIG. 21B is obtained.

In step S36, the boundary color numbers # (x + 1) and # (x + 2) not registered as new boundary color numbers in the boundary color correspondence table BCT (FIG. 24D) are replaced with the original color numbers # 1 and #. 3 respectively. This conversion is
This is performed with reference to the color number correspondence table CCT (FIG. 20E) together with the boundary color correspondence table BCT. As a result, as shown in FIG. 21C, the new boundary color number # (x
The boundary region R23 having a width of one pixel having (+3) remains, and the original boundary regions R21 and R22 disappear.

In step S37, if necessary, a thickening process for expanding the boundary region R23 by a predetermined width is executed.
The line drawing of FIG. 22A is obtained. The region R thus formed
Reference numeral 24 denotes a fogging region having a predetermined fogging width. Further, as shown in the boundary color correspondence table BCT in FIG. 24D, the value of at least a part of the picture priority flag of the fog region R24 is 1. The color plates Y, M, and K in which the value of the picture priority flag is 1 are the color plates whose line drawing is determined to be weaker or almost equal to the picture in the strength determination table (FIG. 24C).

The fog region R24 shown in FIG.
Are equivalent to the line drawing of FIG. 13B in the outer mode and the line drawing of FIG. 15B in the inner mode. That is, steps S26 to S28 in FIG. 10 are executed based on the line drawing in FIG. FIG. 22 also shows the state of the processing in steps S26 to S28. First, in step S26, FIG.
A 1 / N priority thinning-out is performed on the pixel with the picture priority flag of 1 for the line drawing of 2 (A), and a mask line drawing of FIG. 22 (B) is obtained. Then, in step S27, FIG.
The pattern of FIG. 22D is pasted using the mask line drawing of FIG. 2B to create the pattern of FIG. Then, in step S28, the mask line drawing data is erased.

Thereafter, in step S9 (FIG. 3), the picture of FIG. 22 (E) and the line drawing of FIG. 22 (A) are combined to record the integrated image of FIG. 22 (C) as a mesh image. .

As described above, in the outer mode or the inner mode, a fogging region having a predetermined width is formed at a portion in the fog direction designated in advance from the boundary between the line drawing and the picture. In addition, a color plate to be subjected to fogging (a color plate not to be fogged in the above example) is also specified in advance. on the other hand,
In the integrated image formed in the auto mode, the overlapping region R24 is formed only at a part of the boundary between the picture and the line drawing. That is, the fogging region is formed only in a portion where a noticeable white spot is likely to occur due to misregistration. Further, the color plate to be subjected to the fogging is determined based on the strength relationship between the halftone dot area ratio of the picture and the line drawing at the boundary. Therefore, the fogging process can be performed without the operator designating the color plate to be fogged.

The present invention is not limited to the above embodiment, but can be implemented in various modes without departing from the gist of the invention.

[0074]

As described above, the first embodiment according to the present invention is described.
In the fog processing method, the fog direction indicating the direction in which the fog area is formed and the color component of the line drawing image adopted in the fog area are specified in advance, so that the fog area of the desired color component is placed on a desired side of the boundary. Can be formed. Also, priority data indicating which of the line drawing image and the pattern image is prioritized in the fog region is created with the resolution of the line drawing image. By combining the image and the image, there is an effect that a combined image including a fog region can be created.

Further, in the second fog processing method according to the present invention, a fog candidate area is formed at the boundary with the resolution of the line drawing image, and a color component having a difference of a predetermined amount or more in density for each pixel of the fog candidate area. Priority data indicating that the line drawing image and the picture image are superimposed is created. Then, by referring to the priority data, a composite image including the fog region is created by synthesizing the line image and the pattern image with a resolution higher than the resolution of the line image, so that the operator can superimpose the color in the fog direction and the fog region. There is an effect that a fog region can be formed without designating a component.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing an overall configuration of an image processing system that performs a fogging process on an image by applying an embodiment of the present invention.

FIG. 2 is a block diagram showing an internal configuration of the image processing apparatus 300.

FIG. 3 is a flowchart illustrating a procedure of a plate making process including a step of performing a fogging process by applying an embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a line drawing, a pattern, and an integrated image thereof.

FIG. 5 is an explanatory diagram showing processed line drawing data.

FIG. 6 is an explanatory diagram showing the contents of a color palette.

FIG. 7 is a conceptual diagram showing a configuration of picture data.

FIG. 8 is a block diagram illustrating a schematic configuration of a recording scanner.

FIG. 9 is an explanatory diagram showing a comparison between a pixel of a line drawing and a pixel of a picture.

FIG. 10 is a flowchart showing a detailed procedure of a fogging process in step S9.

FIG. 11 is an explanatory diagram showing a procedure of a process in a case where the kabuse process is not performed.

FIG. 12 is an explanatory diagram showing that priority thinning processing is not performed.

FIG. 13 is an explanatory diagram showing a procedure of a fogging process in the outer mode.

FIG. 14 is an explanatory diagram illustrating a method for determining color data of a fog region in an outer mode.

FIG. 15 is an explanatory diagram showing a procedure of a fogging process in the inner mode.

FIG. 16 is an explanatory diagram showing a method for determining color data of a fog region in the inner mode.

FIG. 17 is an explanatory diagram showing a case where a fog region is formed in the auto mode.

FIG. 18 is an explanatory diagram showing a case where no fog region is formed in the auto mode.

FIG. 19 is a flowchart showing a detailed procedure of a fogging process in the auto mode.

FIG. 20 is an explanatory diagram showing processing contents in the procedure of FIG. 19;

FIG. 21 is an explanatory diagram showing processing contents in the procedure of FIG. 19;

FIG. 22 is an explanatory diagram showing processing contents in the procedure of FIG. 19;

FIG. 23 is a flowchart showing a detailed procedure of step S33.

FIG. 24 is an explanatory diagram showing the processing content of step S44.

FIG. 25 is an explanatory diagram showing the effect of the presence or absence of a fog region.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 100 ... Planar scanner 200 ... Color separation scanner 300 ... Image processing apparatus 302 ... CPU 304 ... Bus 306 ... ROM 308 ... RAM 310 ... Line memory 312 ... Line drawing memory 314 ... Picture memory 316 ... I / O interface for keyboard 318 ... Keyboard 320 mouse 322 display control unit 324 color CRT 326 image data input interface 400 recording scanner 402 run length memory 404 picture memory 408 bitmap development circuit 410 read address / clock generation circuits 412 and 414 ... AND gate unit 416... OR gate unit 418. ... color palette Fy, Fm, Fc, Fk ... picture priority flag

Claims (2)

(57) [Claims] 1. A fogging processing method for creating a combined image by combining a color line drawing image and a color pattern image while overlapping each other at a boundary between the color line drawing image and the color pattern image, comprising: (a) Preparing picture image data representing a plurality of color components of the picture image at a first resolution; and (b) line drawing expression data representing a plurality of color components of the line picture image at a second resolution higher than the first resolution. Preparing line drawing image data including: a priority image indicating which of the pattern image and the line drawing image is prioritized for each pixel of the line drawing image; and (c) a boundary between the line drawing image and the pattern image. In the above, a fog direction indicating whether a fog area is formed on the line drawing image side or on the picture image side is designated, and the color of the line drawing image to be adopted in the fog area is specified. (D) forming, at the second resolution, a fog region having a predetermined width extending in the fog direction from a boundary between the line drawing image and the picture image; As the color component of the region, the step (c)
The priority data is updated so as to indicate that the line image is prioritized for the color component of the type specified in the above, and that the pattern image is prioritized for the color component other than the type specified in the step (c). (F) creating a synthesized image by synthesizing the line drawing expression data and the picture image data at a resolution equal to or higher than the second resolution while referring to the updated priority data; A fogging processing method comprising: 2. A fogging processing method for creating a composite image by combining a color line drawing image and a color pattern image while overlapping each other at a boundary between the color line drawing image and the color pattern image, comprising: (a) Preparing picture image data representing a plurality of color components of the picture image at a first resolution; and (b) line drawing expression data representing a plurality of color components of the line picture image at a second resolution higher than the first resolution. Preparing line drawing image data including: a priority image indicating which of the pattern image and the line drawing image is prioritized for each pixel of the line drawing image; and (c) a boundary between the line drawing image and the pattern image. Forming, at the second resolution, a fogging candidate region having a predetermined width; and (d) in the fuzzing candidate region, the density of each color component of the line drawing image and the pattern image is determined for each pixel. Comparison, the line
The density of the picture image is larger than the density of the picture image by a predetermined amount or more.
The color component and the density of the pattern image are the density of the line drawing image.
When color components larger than the specified amount by more than
A color component whose density of the line drawing image is higher than the density of the pattern image by a predetermined amount or more is given priority to the line image, and a color component whose density of the pattern image is higher than the density of the line image by a predetermined amount or more. Updating the priority data so as to indicate that the picture image is prioritized; and (e) referring to the updated priority data and comparing the line drawing expression data with a resolution equal to or higher than the second resolution. Creating a combined image by combining the picture image data with the picture image data.