JPH0227369A - Color picture processor - Google Patents

Abstract

PURPOSE:To execute a correct color conversion processing by changing color information of an original related to color information for designating an area to the color information for designating an area. CONSTITUTION:In a marker correcting circuit 600, picture data of a single picture element of a several picture elements portion or a several lines portion is referred to, and when there is color information of the original related to color information of a color marker for designating an area, this color information is changed to the color information of the color marker. Therefore, in the marker correcting circuit 600, correcting tables 603, 606 for the color information are prepared, and when combined color information is inputted, its notice picture element is changed to the color information of the color marker.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a color image processing device suitable for application to an image processing device such as a plain paper recording color copying machine, and particularly to a color image processing device having a partial color conversion function. The present invention relates to a color image processing device that allows area designation information to be detected accurately in a processing device.

[Background of the Invention] In a color image processing device, such as a color copying machine using a laser beam, a color original is separated into multiple colors to obtain color image information, and a color image is recorded based on this color image information. I try to do that.

Such color copying machines are capable of various image processing such as scaling processing and partial color conversion processing.

Partial color conversion processing refers to image editing processing that allows image information inside or outside a designated area to be recorded in the color used for specifying the area, for example.

Areas are usually specified using color markers. For example, when area a is specified using a helmet marker as shown in Figure 20A, the image included in area a is recorded in the same color as that used for area specification, in this example blue (Figure 20A). )
.

Images in other areas may be erased or recorded as normal black and white images.

In order to achieve such partial color conversion processing, it is necessary to detect each color for specifying an area, such as a color marker, and the area. To do this, for example, as shown in FIG. 21, marker signals BP and RP are detected from color markers formed across each scanning line (n, n+1, etc.), and from these, area signals QB' and OR are detected. - can be formed.

These markers (g No. BP, RP and area signal QB".

Based on OR', the image of the designated area is extracted and recorded, and the recording process as shown in FIG. 20B is achieved.

[Problem to be solved by the invention]

By the way, in a color image processing apparatus equipped with such a partial color conversion processing function, if the image information of the document and the image information of the color marker cannot be accurately discriminated, it will not be possible to correctly perform color conversion within the designated area.

In particular, when a color marker and a document image intersect, for example, a black fir tree or a horizontal ruled line, the color marker is written on top of the ruled line, so that part is not used as information about the color marker, but rather as image information of the document. It can only be obtained as

For example, in a part where a black ruled line and a color marker intersect as shown in FIGS. 22A and B, at both ends of the intersecting outline,
Although you can get information about color markers, you can only get information about ruled lines inside of it.

Therefore, the color marker information is interrupted at this intersection, making it impossible to correctly perform color conversion processing at the intersection.

Accordingly, the present invention proposes a color image processing apparatus having a partial color conversion processing function, which is capable of accurately detecting color markers.

[Means for Solving the Problems 1] In order to solve the above-mentioned problems, the present invention provides a color image processing device that performs image processing on color image information converted into an electrical signal. The system includes a color discrimination means for color image information, a color ghost correction means, and an image processing means for performing image processing on a specified area using color information different from the color of the original to be read. The present invention is characterized in that a small portion (at least a portion) of the color information of the document adjacent to the color information for specifying the area is changed to the color information for specifying the area.

[Operation] In order to accurately detect the area of the color marker, a marker correction circuit 600 is provided (FIG. 12).

The marker correction circuit 600 refers to the image data of a single pixel for several pixels or lines, and when there is color information of the document adjacent to the color information of the color marker that specifies the area, this color information is Change to marker color information (data replacement).

Therefore, a color information correction table is prepared in the marker correction circuit 600, and when the combination of color information as described above is input, the pixel of interest is changed to the color information of the color marker (FIG. 10).

If the color information is changed to the color marker, even if the image information of the document and the color marker intersect, the color marker data will not be interrupted, so the designated area can be detected accurately.

[Example] Next, an example of a color image processing device according to the present invention will be described.
A case in which the present invention is applied to the color image processing apparatus of the color copying machine described above will be described in detail with reference to FIG. 1 and subsequent figures.

FIG. 1 shows an example of a color image processing device 1 according to the present invention, in which color image information (optical image) of a subject 2 such as a document is transmitted to a dichroic mirror 4 through an optical system 3.
It can be separated into two color separated images.

In this example, the image is separated into a color-separated image of red R and a color-separated image of cyan Cy. Therefore, the cutoff wavelength of the dichroic mirror 4 used is approximately 540 to 600 nm.

The color separated images of red R and cyan cy are supplied to image reading means, for example, CCDs 6 and 7, and image signals of only the red component R and cyan component Cy are output from each image reading means, for example.

The image signals R, cy are supplied to the A/D converters 10, 11- and are converted into digital signals of a predetermined number of bits, in this example 6 bits. Shading correction is performed simultaneously with A and /D conversion. 12.13 shows a shading correction circuit.

The digital image signal subjected to the shading correction is extracted by the effective area extraction circuit 15 for only the signal corresponding to the maximum document size width, and is supplied to the color discrimination circuit 20 at the next stage. When the maximum document width to be handled is 84 size, the size signal B4 generated by the timing signal generating means 170 of the system is used as the gate signal.

Here, if the digital image signals subjected to shedding correction are VR and VC, respectively, these image signals VR.

VC is supplied to a color discrimination circuit 20 and separated into a plurality of color signals.

In this example, a case is illustrated in which the configuration is completed so as to separate the colors into three colors No. 18: red, helmet, and black.

That is, no matter what color the original is, each pixel is assigned to one of red, blue, and black. When this process is performed, each part of the document is recognized as a red, blue, or black color part.

In addition, if these red, blue, and black are other colors, roughly 4
This color discrimination processing also includes the determination of a color or more.

Each color-discriminated color signal is divided into color code data (2-pit chip) indicating its color information and density data (
6-bit data).

The data for each color signal is stored in a color discrimination conversion table (map) in a ROM, for example.

FIG. 2 shows an example of this color discrimination map.

It is also possible to prepare a plurality of color discrimination conversion tables and select one of them depending on the type of document, for example. In this case, table selection processing is executed based on instructions from a microcomputer, which will be described later.

The color-discriminated image data is transferred to a color image processing step.

First, the color ghost is completely supplied to the next-stage color ghost correction means 300, and color ghosts in the main scanning direction (horizontal scanning direction) and the sub-scanning direction (drum rotation direction) are corrected.

This is because unnecessary color ghosts occur during color discrimination, especially around black characters.

FIG. 3 shows an example of appearance of color ghosts.

The figure shows the color ghost that appears after color discrimination is performed by capturing an image of the kanji character "sexuality" written in black.

As you can see from this example, as a color ghost,
As shown in FIGS. 4A to 4C, red and blue appear at the edge of the black line, black appears at the edge of the blue line, and black appears at the edge of the red line.

It is clear that color ghosts appear differently in other color combinations.

The color ghost correction means 300 is a circuit for correcting such color ghosts as much as possible. Note that color ghost processing is applicable only to color code data.

In this example, color ghost correction is performed using a color pattern method. This is because the color ghost color that appears is determined for the original color, such as original black → red, helmet ghost original red, blue → black ghost. Therefore, according to this color pattern method, the color of the original image can be identified by examining the color appearance (pattern) of the pixel of interest and its surrounding pixels to determine the color of the pixel of interest.

As an example, FIG. 5 shows the relationship between the pixel of interest, the surrounding color pattern, and the color of the pixel of interest determined at that time.

In the first example, since both sides of the pixel of interest are white and black, the blue color of the pixel of interest is determined to be a color ghost appearing at the black edge. Red in the third example is also determined to be a color ghost of black. Therefore, in both the first and third examples, the pixel of interest is changed to black.

On the other hand, in the second and fourth examples, it is not determined that a color ghost has appeared, and the color of the pixel of interest is output as is.

This type of processing is difficult to implement with an arithmetic circuit, so in this example, it is implemented in ROM and LUT (lookup table).
It is used in the format. As a color pattern, one-dimensional and two-dimensional systems are possible, but if the number of colors is N and the number of surrounding pixels including the pixel of interest is M, the size of the color pattern is N8. Therefore, if a two-dimensional pattern is used, the number of M will suddenly increase, making it impractical.

In other words, in a two-dimensional pattern, each dimension direction (main scanning direction/
Although the number of peripheral pixels in the sub-scanning direction (sub-scanning direction) cannot be increased, the number of patterns increases. FIG. 6 shows the relationship between size and number of color patterns.

In this example, the size of IX7 in one dimension (that is, N
=4. M=7) color pattern is used, and color ghost removal is performed independently in the main scanning direction and the sub-scanning direction.

At this time, since there is no difference in the appearance of color ghosts in the image between the main scanning direction and the sub-scanning direction, the same color pattern is used in the main scanning direction and the sub-scanning direction in this example.

The color pattern size is 1 x 7, but if the degree of color ghost appearance is small, I
It is also possible to use smaller sized color patterns such as X5.

In a color pattern of size 1x5, one pixel is 1x7.
With this color pattern, color ghosts of up to two pixels can be removed.

When a 1×7 color pattern is used, the color code is input as a ROM address. for example,
In the color pattern below, the color code pattern is white: white: blue: helmet: black: black: black 11: 11:01:01:oo:oo:o.

The next address is As shown in FIG. 5, a black code O is stored at this address. The LUT is executed using the above method.

In reality, the x7 pattern requires a 14-bit address line, and a bipolar ROM with 14-bit address input and 2-bit color code output is sufficient, but with such a large capacity and high speed, ROMs are not widely available on the market and are expensive. Further, the output of the ROM is generally 8 pits.

Therefore, in the embodiment, the output data of the ROM is selected based on the color code of the first pixel, and the LUT is performed using the color codes of the remaining six pixels. That is, the output data Do, Dl of the ROM are selected when the first pixel is black, and the output data D2. D3 is blue, D4. D5 is red, D6. D7 is selected when it is white.

Therefore, for example, in the color pattern shown in FIG. 5, the beginning is white, so in this case, among the output pits of the ROM,
Bit D6. Both D7 will be selected.

However, even if the leading pixel is the same white, the color codes of the target pixel obtained in the selected output bits DB and D7 are different as shown in FIG. This is because the reference address (ROMg) differs depending on the combination of input pixels (combination of color code data).

When using a low-speed, large-capacity EFROM, it is also possible to transfer data to a plurality of SRAMs or the like before operation and perform color ghost correction using these SRAMs.

The image data (color code data and density data) after the color ghost correction is processed in the subsequent resolution correction circuit 40, and the resolution (MTF) is corrected.

Factors contributing to resolution deterioration include problems with the optical system, optical travel system, signal processing system, recording system, etc. However, it is the optical system and its travel system that directly affect the deterioration of resolution.

FIG. 7 shows MTF values (before correction) in the main scanning direction and the sub-scanning direction when the optical system is driven. This characteristic is 2~16d
These are the measured values when scanning a black and white pattern with a spatial frequency of up to ots/m111.

The MTF in this case was defined and used as MTF=(W-BK)/(W+BK)(%). Here, W is a white signal and BK is a black signal.

The deterioration of MTF is more significant in the sub-scanning direction. To make the same amount of correction, the amount of correction in the sub-scanning direction should be 2 times that of the main-scanning direction.
It should be set to ~4 times.

To correct the main and sub-scanning directions to the same degree without deteriorating the reproducibility of fine line parts, 1. As the resolution correction circuit, a convolution filter using 3×3 pixel image data or the like can be used.

FIG. 8 shows the correction results when using a convolution filter.

The resolution-corrected density data and color code data are each supplied to a color data selector 50, and when the partial color conversion mode is selected, the image area is recorded in a specific color.

When performing image processing such as this partial color conversion mode, it is necessary to detect color markers written on the document and extract the area.

For this reason, a region extraction circuit 60 is provided to detect the color marker region on the document, and the region signals QR-, QB" (see FIG. 21) obtained from this are supplied to the data selector 50. Ru.

In addition to these signals, the data selector 50 is supplied with a scan code (No. 8) indicating which color is currently being copied and a processing designation signal (partial color conversion signal) CC.

It is a multi-color copying machine that can record multiple specific colors, and it develops one color per rotation of the photoreceptor drum, and after all colors are developed,
In a type of printer that records a color image by performing transfer separation processing, the scan code signal indicates which color is currently being developed.

Therefore, when a blue color marker is detected, the corresponding color data can be output during the blue copy sequence and when the area signal is obtained.
Images within the blue color marker can be recorded in blue.

When not performing partial color conversion processing, density data is output only when the color code data matches the scan code signal. That is, at the end of the red copy sequence, the corresponding density data can be selectively output while the red color code is being used.

The image data output from the color data selector 50 (
The density data) is subjected to enlargement/reduction processing in a scaling circuit 70.

Enlargement/reduction processing is performed by interpolating the density data in the main scanning direction, and by controlling the scanning speed in the sub-scanning direction (rotation direction of the photosensitive drum).

If the scanning speed is increased, sampling data in the sub-scanning direction is thinned out, resulting in a reduction process; on the other hand, if the scanning speed is made slower, an enlargement process is performed.

In this example, the color code data is also subjected to enlarging/reducing processing at the same time, and is then supplied to the multi-value conversion circuit 80.

The density data subjected to the enlargement/reduction processing is sent to the multi-value conversion circuit 8o.
, multi-value processing is performed. For example, by using four threshold values, 6-bit density data is quinarized.

Threshold data is set manually or automatically.

A pistogram creation circuit 100 is provided to automatically determine threshold data.

The pistogram creation circuit 100 creates a density histogram as shown in FIG. 9 from certain captured image data, and calculates optimal threshold data for the image based on the created density histogram.

A density histogram may be created for each color, and multi-value processing may be performed for each color using threshold data calculated based on the density histogram.

The 3-bit multi-value data that has been subjected to multi-value processing is supplied to the driver 140 via the interface 130.

The driver 140 modulates the laser beam in accordance with the multilevel data. In this example, PWM modulation is performed.

The driver 140 may be built into the multi-value conversion circuit 80.

Output device 150 by a PWM modulated laser beam
The photoreceptor drum installed at W ($1) is charged.

As the output device 150, an electrophotographic color copying machine using a laser beam is used. In this example, two-component non-contact jumping development and reversal development are employed.

In other words, the transfer drum that can be used for conventional color image formation is not used. In order to miniaturize the device, three-color images of helmet, red, and black are developed on the OPC photoreceptor (drum) for image formation in three rotations of the drum as described above, and transfer is performed once after development. , and transfer it to recording paper such as plain paper.

The various image processing commands and image processing timings described above are all controlled by the CPU 160.

170 is a processing timing signal generation circuit for obtaining various processing timings, which includes a clock CLK, horizontal and vertical synchronization signals HV in the main scanning direction and sub-scanning direction obtained from the output device 150 side, V
An index signal IDX indicating the start of scanning of the laser beam is supplied to the V-coat, and based on these signals, the C
A quenching signal for starting reading of the CD 6.7 is generated.

180 is a timing signal generation circuit for obtaining scaling timing.

In this invention, when the partial color conversion mode is selected and an area is specified on the document using a color marker,
When there is an intersection as shown in FIG. 22, this is automatically detected and the content of the image data is changed as color information of the color marker.

In this way, if the image information of the document, for example, a ruled line and a color marker intersect, at least one
There are pixels (Fig. 22). Then, color information different from this color information can be detected consecutively for at least several pixels from the information indicating this color marker.

For example, if the line intersects with the ruled line as described above, the first
As shown in Figure 0, color information that differs by 5 to 8 pixels is successively obtained. Although the figure shows the case where a red color marker is used, the same applies when a blue color marker is used.

Therefore, among the information adjacent to the color marker, image information for a predetermined number of pixels (pixel of interest) is replaced with color information of the color marker.

To copy the image in the specified area a in the specified color, as shown in FIG. It is necessary to detect the area signals QB'' and QR= indicating respectively.

Therefore, as shown in FIG. 1, a color data selector 50 is provided in addition to the area extraction circuit 60. The color data selector 50 is a circuit for selecting density data of a developed color corresponding to a copy sequence (development sequence) when specifying a partial color and selecting density data of a developed color corresponding to a copy sequence during normal copying. It is.

FIG. 11 shows a specific example of the area extraction circuit 60, in which each bit data of color code data obtained by scanning a color marker is supplied to a color marker correction port 8600, and color information as described above is generated. Change (replacement) processing is performed. The color code data for which the modification processing at the intersection has been completed is supplied to the color marker detection circuit 501, and the presence or absence of a specific color marker can be detected. In the embodiment, since the present invention is applied to two types of markers, red and blue, two marker signals BP and RP are detected.

The marker signals RP and BP are fully supplied to the region extraction section 520, and region signals QR'' and QB' indicating the inside of the specified region a are output for each scanning line.

These more specific configurations will be explained below.

FIG. 12 shows an example of the color marker correction circuit 600. The range of pixels to be corrected also depends on the type of original that can be used, but for normal office paper, the lines are 0.
．． 2 to 0.3 mm, commercially available plotter pens are also 0.2 to 0.
．． It is about 51. Therefore, in the embodiment, the range of the correction amount was limited to 0.5ml0.

In the case of a reading resolution of 16 dots/in, this corresponds to approximately 8 pixels, so a pattern as shown in FIG. 10 may be considered.

For this purpose, image data for eight pixels is subjected to parallel conversion processing in each of the main scanning direction and the sub-scanning direction.

Therefore, as shown in FIG. 12, the input color code is supplied to the input terminal of the first stage of the latch circuit 602. Then, the color code outputted from this is supplied to the input terminal of the second stage, and similar processing is performed thereafter up to the final stage (eighth stage). As a result, an output color code obtained by sequentially shifting the input color code by one pixel is obtained at each output terminal.

By doing this, the color codes for 8 pixels are parallelized, and these are supplied to the correction table 603.
Correction data is referenced.

In the correction table 603, when a black color code, which is image information, is input after a color code indicating a color marker as shown in FIG. are stored in a table.

Therefore, when color markers and image information color codes are input in the arrangement shown in FIG. 10, all black color codes are changed to red color codes. After the change processing in the main scanning direction is completed, a similar change processing in the sub-scanning direction is executed.

Therefore, a line memory 605 for parallelization and a correction table 606 are provided, and the correction table is referred to by the parallelized 8 lines of color code data, and the color code data of the corresponding pixel is changed to the color code of the color marker. changed to data.

In this case as well, the conversion table shown in FIG. 10 can be used.

The line memory 605 is configured by cascading line memories for eight lines.

The latch circuit 602 may be configured by connecting five of seven latch circuits.

When the process of changing the color code at the intersection with the color marker is completed in this way, the next step is the process of detecting the color marker.

FIG. 13 shows an example of a color marker detection circuit 501.

Here, if the relationship between the color information and the color code is determined as shown in FIG. 14, the blue color code data will be 01°, and the red color code data will be 10°.

In FIG. 13, of the color code data, upper bit data and lower bit data whose phases are inverted by an inverter 511 are supplied to one NAND circuit 513.

Similarly, the phase of the lower bit and upper bit data are inverted by the inverter 512, and the other NAND circuit 514
is supplied to And vertical effective area No. 4' V-VALI
The AND output of D and the size signal B4 is supplied to each NAND circuit 513 and 514 as a gate signal. 515 indicates an AND circuit.

As a result, when the color marker is blue, the blue marker signal B has a pulse width corresponding to the thickness of the outline of the marker.
P (FIG. 21) can be output from the terminal 516.

Similarly, when the color marker is red, a red marker signal RP (FIG. 21) is output to the other terminal 517.

An example of the area extraction section 520 is shown in FIG.

The area extraction unit 520 includes first and second area extraction units 520A.
, 520B, each of which is a data storage circuit 521A.
, 522A and area calculation circuits 521B and 522B. Both the first and second area extracting units 520A and 520B have a function of extracting a red marker area in addition to a function of extracting a blue marker area. For convenience of explanation, region extraction of the blue marker will be explained.

When forming a blue area signal, the area signal of the current scanning line is calculated and formed from the area signal obtained by scanning immediately before and the marker signal obtained by scanning the current scanning line.

For this purpose, it is necessary to perform arithmetic processing using a period of at least 63 lines. Therefore, the first data storage circuit 521A has the function of storing the area signal, which is the final data of the immediately preceding scanning line, over one line, and also from the marker signal BP obtained by scanning this area signal and the current scanning line. The formed first and second area signals (
In reality, it is necessary to have a function to memorize the NAND output) and a function to memorize the area signal of the current scanning line obtained by roughly processing these area signals.

Furthermore, in the embodiment, the second area signal is formed by reading the memory from the reverse direction, so the number of memories required to realize these memory functions is:
There will be 16 pieces in total. Roughly speaking, it is necessary to detect the red marker, so 32 line memories are required in total.

Therefore, the first data storage circuit 521A has a pair of memories 525 and 526 each composed of eight (8 bits) line memories. In order to switch and use these for each line, a pair of 3 state buffers and 5 state buffers are used.
23, 524, a pair of data selectors 527, 528, and a latch circuit 529 are provided.

The first data storage circuit 521A receives the helmet marker signal BP as an input signal as well as the first area calculation circuit 530 for blue.
The three signals obtained at B are provided.

In the first region calculation circuit 530B, the immediately preceding region signal QB
The area signal QB- of the blue marker on the current scanning line n is formed from the marker signal BP on the current scanning line.

For convenience of explanation, considering scanning line n shown in FIG. 21, the relationship between area signal QB (this is the area signal of scanning line (n-1)) and marker signal BP is as shown in FIG. 16B.
, as shown in C. These signals can be stored line by line in the memory 525.

In the next scanning line (n+1), these signals are read out via the data selector 527 and latch circuit 529 (E in the figure).

A pair of signals QB and BP are supplied to a NAND circuit 531,
The preset pulse FBI (F in the same figure) which is the NAND output is the preset terminal P of the D-type flip-flop 532.
R is completely supplied, and the immediately preceding area signal QB is sent to its clear terminal CL.
is supplied to As a result, the first NAND output (first contour No. 3) BNO as shown in FIG. G is obtained.

The first NAND output BNO and marker signal BP are stored in memory 526 sequentially. Therefore, scanning line (n+1
), the active state of the 3-state buffer 524 is controlled.

A similar processing operation is also executed at the same timing in the second area extraction unit 520B. However, all of the memories provided therein are subjected to address control 11 so that writing is performed in the forward direction and reading is performed in the reverse direction.

Therefore, the output timing of the marker signal BP and the immediately preceding area signal QB is Wl for the n line, whereas the output timing is Cn+
1) The line becomes W2 and is read out a little faster (H and I in the figure). As a result, the second NAND output B
NI will be as shown in the same figure. The marker signal BP and the second NAND output BN1 are again stored in the data storage port 11521B.

In the next scan line (n+2), the first NAND output BN
O, the marker signal BP and the second NAND output BNI are read out (M in the same figure).

Here, as described above, the memory provided in the second area extracting section 520B reads out the data in the forward direction w and in the reverse direction, so in this example, the first NAND output BNI and the second
Read timing of NAND output BN2 W3. W4 matches.

Both are supplied to the AND circuit 533, and by supplying the AND output AB and marker No. 48 BP (N, O in the figure) to the OR circuit 534, an OR output Q as shown in P in the figure is obtained.
B' is obtained.

This OR output QB' is nothing but a signal indicating the inside of the outline of the blue marker drawn on the current scanning line n. In other words, this OR output becomes the area signal QB' of the current scanning line.

The area signal QB' is used as the immediately preceding area No. 43 QB on the next scanning line, so the data storage circuit 521
It is easy to understand that the feedback is given to A and 521B.

Thus, a pair of NAND outputs BNO obtained by reversing the memory read direction.

By using BNI, marker areas can be detected accurately.

Since the detection of the red marker is exactly the same, the area calculation circuit 5
Description of 30R will be omitted. However, 535 is a NAND circuit, 536 is a D-type flip-flop, 537 is an AND circuit, and 538 is an OR circuit.

QR' indicates a red marker area signal.

3. State buffers 523, 524, memory 525.
The reason why a pair of data selectors 526 and data selectors 527 and 528 are provided is to enable the data storage circuit 521Δ to read and write the memory at the same time.

Therefore, by the two-line cycle switching signal 48 supplied to terminals A and B, these lines are alternately switched and used for reading and writing on a line-by-line basis.

The regions obtained at the output terminals (No. i QB-9QR-) are supplied to the region determining section 540 constituting the color data selector 50 as shown in FIG.

The area determination unit 540 is a control means for area signals so that when a marker is designated as shown in FIG. 19A, an image is recorded as shown in FIG. 19B.

That is, in sections I and ■, black and white images are recorded, and in sections [1
, IV, a black image is recorded as a red image, and in section +11, a gate signal S of density data is formed from the area signals QB', QR'' so that a black image is recorded as a blue image. Ru.

FIG. 17 shows an example of the area determination section 540, which includes four flip-flops 541 to 544, including front-stage flip-flops 541. ．． Area signal QB latched at 542
', QR'' are supplied to the corresponding NAND circuits 545 to 548, and the area signal QB''QR= latched by the flip-flops 543 and 544 in the subsequent stage is supplied to the corresponding NAND circuit 5.
45-548. Color code data C indicating black is supplied to each of the NAND circuits 545 to 548 via an AND circuit 554. A scan code signal indicating which color is currently being copied is supplied to the switching circuit 553.

Therefore, by the signals shown in FIG. 18A-C, the first NAND circuit 545 outputs the first NAND output M1 shown in the same figure.
is obtained. Similarly, the second NAND circuit 546 obtains a second NAND output M2 shown in G in the same figure based on the input signals shown in E and F in the same figure. As a result, the first AND circuit 551 outputs the gate signal S1 related to the section 11 shown in H in the same figure.

Similarly, the third NAND output M3 in the figure is obtained from the input signal J- in the figure, and the fourth NAND output M4 shown in the figure is obtained from the input signals M and N in the figure.

As a result, the second AND circuit 552 outputs the gate signal S2 (P in the figure) related to the sections II and (2).

Then, the gate signal S3 (corresponding to sections ■ and ■) is sent from the fifth NAND circuit 549 by the input of Q-3 (No.
T) in the same figure is output.

Gate signals 81 to S3 are selected by switching circuit 553 according to a scan code signal indicating a copy sequence. Therefore, the gate signal S1 is selected in the blue recording mode, the gate signal S2 is selected in the red recording mode, and the gate signal S3 is selected in the black recording mode.

The above operations are executed when the processing designation signal CC is in the partial color conversion mode. In other modes, it is controlled by color code and scan code.

Gate signal 81 output from switching circuit 553
~S3 are supplied to a density data selection circuit 574 shown in FIG. 17, and density data corresponding to the color code data is selected.

In that case, white density data (always 1) is selected in sections other than the gate signal S. Therefore, for example, in the blue recording mode, white data is always selected except for section 111. As a result, in the blue recording mode, a blue image is recorded only in section II+, in the red recording mode, a red image is recorded only in sections TI and ■, and in the last black recording mode, only sections I and V are recorded. A black image is recorded (FIG. 19B).

Note that the density data is delayed by eight lines by the delay circuit 575 and is input to the data selection circuit 574. This is to ensure temporal consistency with the density data since the data for the color marker is changed in the sub-scanning direction.

By providing the area determination unit 540 as described above,
Even if areas are specified in duplicate, priority is given to the color of the inner marker. The non-overlapping area will be copied using the color of the marker that specified the non-overlapping area.

A modified example of partial color conversion is shown below.

Partial color conversion essentially refers to the detection of a specified area and the processing of image data or colors within the specified area, so it can be used to extract, erase, invert, mirror image, enlarge/reduce, and move the partial area. , any combination of these can be processed using the same concept.

It is also possible to predetermine the processing content for each color marker and perform the pre-booked processing on the detected area.

As the color marker, red-based colors (orange, pink) and blue-based colors are suitable. This is because these colors are difficult to copy completely in the normal copy mode.

If it is not possible to write color markers directly on the original, the same effect can be achieved by marking on a transparent sheet.

[Effects of the Invention] As described above, according to the present invention, the color information of the document that is in contact with the color information for specifying an area is changed to the color information for specifying the area.

According to this method, the color marker information that is hidden by the image information of the document can be reliably supplemented, so that the designated area of the color marker can be accurately detected. by this,
Correct color conversion processing cannot be performed.

Therefore, the present invention is extremely suitable for application to a color image processing apparatus such as the above-mentioned color copying machine.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing an example of a color image processing device according to the present invention, FIG. 2 is a diagram of a color discrimination map, FIGS. 3 and 4 are explanatory diagrams of color ghosts, and FIGS. The figure is an explanatory diagram of color ghost correction, and Figures 7 and 8 are MTF.
A characteristic diagram showing the correction, FIG. 9 is a diagram of a density histogram, FIG. 10 is an explanatory diagram of how the color marker is changed, FIG. 11 is a system diagram of the area extraction circuit, and FIG. 12 is a system diagram of the marker correction circuit. Fig. 13 is a system diagram of the marker detection circuit, Fig. 14 is an explanatory diagram of color code data, Fig. 15 is a system diagram showing an example of the area extractor, Fig. 16 is a waveform diagram for explaining its operation, and Fig. 17 is a system diagram of the marker detection circuit. The figure is a system diagram of the color data selector, Figure 18 is a waveform diagram for explaining its operation, Figure 19 is a diagram showing the relationship between color markers and recording areas, and Figures 20 and 21 are parts provided for this invention. FIG. 22, which is an explanatory diagram of the color conversion process, is an enlarged view of the color marker. 1...Color image processing device 20...Color discrimination circuit 40...Resolution correction circuit 50...Color data selector 60...Area extraction circuit 70...Scaling circuit 80...Multiple units Value conversion circuit 100... Histogram creation circuit 150... Output device 160... CPU 300... Color ghost correction means 501... Marker detection circuit 520... Area extraction unit 600... Marker correction circuit Patent Applicant: Konica Co., Ltd. A Figure Pixel of Interest Figure Section 〈 C Section D KuC Co. No. 18 F A Fig.

Claims (1)

[Claims] (1) In a color image processing device that performs image processing on color image information converted into an electrical signal, the color image information is read by a color discrimination means and a color ghost correction means. image processing means for performing image processing of a specified area using color information different from the color of the original document; A color image processing device characterized in that the color information is changed to color information.