JPH0816924B2 - Color image processing device - Google Patents

Description

The present invention relates to a color image processing apparatus.

[Prior Art] In recent years, much image information has been handled as color image information, and a color image forming apparatus for reading and reproducing color image information has been actively developed. Above all,
The realization of a pictorial color copier capable of reproducing halftones is currently highly anticipated.

Further, the color copying machine handles color information unlike the conventional two-color black and white copying machine, so that the color of the designated portion in the original is changed to the other color in addition to the color reproduction faithful to the original. To
Alternatively, a new demand has arisen for converting the same color into a color having a different density. In the conventional device, in response to this request, the operator inputs the coordinate value of the periphery of the portion to be color-converted by the digitizer or the ten-key pad of the operation unit to specify the area, and the color information in the area is specified to other areas. It was converted to the color information.

[Problems to be Solved by the Invention] However, in such a conventional apparatus, when performing color conversion of an area having a complicated shape, it is necessary to specify a number of coordinate values, and the area in one screen is further increased. When there are a large number of designated points, there is a problem that the operation becomes very complicated and the scale of the processing circuit such as the memory inevitably becomes large.

It is an object of the present invention to provide a color image processing device that solves the above problems.

[Means for Solving the Problems] In order to achieve the above object, the present invention specifies a position on a document of a desired color which is a color to be converted and which is included in a document when a color conversion process is performed. Position specifying means (corresponding to digitizer 112 in FIG. 2 of the specification in this embodiment), color generating means (in this embodiment, a color signal generating a color signal indicating the converted color when the color to be converted is color-converted). Specification FIG. 8, Latch 303
To 305), illuminating means for illuminating the original document (in this embodiment, page 7, lines 15 to 16 of the specification, corresponding to a halogen lamp), for detecting a color signal corresponding to the desired color,
Storage means for illuminating the position on the document designated by the position designating means by the illuminating means and storing a color signal corresponding to the obtained light (in this embodiment, FIG. 7 in the specification, latches 420 to 420). (Corresponding to 422), based on the color signal corresponding to the desired color stored in the storage means, an equivalent color area for the desired color included in the document is determined, and the equivalent color area is generated by the color generating means. It is characterized by having a color conversion means (corresponding to the color conversion circuit 123 in FIG. 2 of the specification in this embodiment) for converting into a color represented by a color signal.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

A. Basic Structure FIG. 1 shows the basic structure of the embodiment of the present invention. In FIG. 1, a is an image reading unit as a unit for generating color image data, and a color image of an original is read by an image sensor such as a CCD (charge coupled device) and color separated.
Outputs color data (digital data) of a color. Reference numeral b is a position designation means such as a digitizer, and by designating an arbitrary one point within a substantially constant density range of a color image, the position data of the pixel of that one point can be input. Reference numeral c is a density selecting means, which selects and specifies a predetermined density range for the density data of the pixel specified by the position specifying means b. Reference numeral d denotes a color conversion means, which compares the data of the predetermined density range selected and specified by the density selection means c with the color data of the three colors supplied from the image reading means a to determine whether or not it is in the specified density range. It is judged whether or not the color of the density range is converted into another color according to the judgment result.

B. Overall Configuration of Embodiment FIG. 2 shows the overall circuit configuration of a color image processing apparatus according to an embodiment of the present invention. In the figure, 100 is a read-only memory (ROM) in which the control procedure (control program) necessary for color image formation is stored in advance, and 101 is a temporary storage of various flags and data used in the execution of the program. Random access memory used (RA
M). 102 is a microprocessor (CPU) as a central processing unit, and ROM10 connected through a bus BS.
0, RAM101, input / output circuit (I / O) 103
Controls the program in OM100 accordingly.

110 is a scanner drive unit (scan drive unit), which is a CCD
(Charge-coupled device) A halogen lamp for illumination (not shown) for giving reflected light or transmitted light of a color original to the sensor 112, and a pulse motor for moving the optical system (not shown)
And a drive circuit (not shown) that drives them, and is controlled by the CPU 102 through the I / O 103. Reference numeral 111 denotes an operation unit including various input keys and a display unit, which is used to input a copy start, a set number of copies, and display an error. 112 is a digitizer which is a coordinate input device,
When the operator presses a desired position on the original surface having a color to be converted with a pen (not shown), coordinate position information (address information) in the main scanning direction and the sub-scanning direction at that position is transferred to the CPU 102 through the I / O 103. Be transmitted to.

121 is an analog / digital circuit (A / D) that converts the analog image signal of the CCD sensor 120 into a digital image signal, 1
22 is an image processing circuit for performing image processing such as known shading correction, gamma correction and masking correction on the output signal of the A / D 121, 123 is a color conversion circuit which is a main part of the present invention, and 124 is
An interface unit (I / F) controlled by the CPU 102 via the I / O 103, and 125, on the recording medium such as recording paper, the color-converted image information sent from the color conversion circuit 123 via the I / F 124. It is a printer that reproduces and records.

The color conversion circuit 123 is a latch pulse generation circuit 1 as described later.
23A (see FIG. 5), a selector circuit 123B (see FIG. 8), and a decision circuit 133C (see FIG. 7),
The color conversion process according to the present invention is performed on the image signal supplied from the image processing circuit 122 based on the processing mode and the position information designated by the digitizer 112. As the printer 125 described above, various color printers such as a color laser beam printer, a color inkjet printer, and a color thermal transfer printer are used.

C. Overall Operation Next, the overall operation will be described. The CCD sensor 120 moves along with the movement of the optical system (not shown) in the sub-scanning direction, and
The image information of the color image is read line by line and the sensor
It outputs R (red), G (green), and B (blue) analog color image signals color-separated by a color filter provided on the light receiving surface of 120. These R, G, B color image signals are converted into digital amounts representing color density by the A / D 121, and further various image processing such as shading correction and masking is performed in the image processing circuit 122.

Next, the image processing circuit 122 causes Y (yellow), M
The image signal converted into the color signals of (magenta) and C (cyan) is subjected to color conversion processing according to the processing mode and the designated area information in the color conversion circuit 123, and the final image signal after the color conversion processing is Sent to the printer 125 through the I / F124,
A color image is reproduced and recorded on the recording paper in the printer 125 by the Y, M, and C image signals which have been subjected to the color conversion processing. For example, when a color laser beam printer is used as the printer 125, vertical / horizontal sync signals are generated at the positions of the leading edge and the left edge of the image, and Y, M, and C are sequentially generated in the image signals in synchronization with this synchronizing signal. A color image is sequentially formed on the magnetic drum by the laser scanning performed by the raster scanning method, and the toner image of each color developed by the toner of the developing device is accurately superimposed on the recording paper to obtain a full color image by subtractive color mixing. To be

D. Operating Procedure FIG. 3 shows an example of the operating procedure for color conversion in the embodiment of the present invention. As shown in the figure, an area occupied by a desired constant density / tone in the color original 130 for color conversion, that is, an area uniformly occupied by the density data of the three color-separated color components. When converting A into the color of the area B occupied by another certain fixed density, first, an arbitrary point b in the area B is pressed with a pen (not shown) of the digitizer 112, and then an arbitrary point in the area A is selected. 1 point a is pressed. By this pressing, the position information digitizer 112 indicating the pressed coordinates is sent to the CPU 102.

E. Overall Timing FIG. 4 shows the timing of main signals when one sheet is copied in the above-described embodiment of the present invention. As shown in the figure, first, in response to pressing (ON) of the copy key of the operation unit 111, a pre-scan cycle (pre-scan period) is started, and during this period, the digitizer 112 designated by a in FIG.
The density data of the three colors of Y, M, and C at the positions of the point and the point b are stored in the latch in the selector circuit 123B described later through the latch pulse generation circuit 123A described later. Then the printer 12
In the actual scan cycle (actual scan period) for executing recording in 5, while synchronizing with the printer 125, Y,
The image signal (video signal) after the M and C color conversion processing is output to the printer 125 to record an image.

F. Latch Pulse Generating Circuit FIG. 5 shows the circuit configuration of the latch pulse generating circuit 123A which constitutes the color conversion circuit 123 of FIG. The latch pulse generation circuit 123A is a circuit for generating a latch pulse for latching color information at a position designated by the digitizer 112, and as shown in this figure, a main scanning latch (latch circuit) 20
0, a sub-scanning latch (latch circuit) 201, a counter 202, and a sync signal generator 203.

The CPU 102 converts the position information indicating the coordinates of the points a and b (see FIG. 3) obtained from the digitizer 112 into the count values in the main scanning direction and the sub scanning direction, respectively, and the corresponding main scanning latch 200 and the sub scanning. Set each in the latch 201. The sync signal generator 203 outputs the sync signal VSY in the sub-scanning direction.
NC and a synchronizing signal HSYNC in the main scanning direction are generated, and the counter 202 is operated by these synchronizing signals. The counter 202 has the above-mentioned synchronization signals VSYNC and HSYNC.
The number of pulses is counted and the count value is latched 200,
When the corresponding address information (count value) set in 201 is matched, latch signals RDPLS210 and WRPL
Generates a latch pulse for S211.

The RDPLS210 has a point a (third position) having color information before color conversion.
(Refer to the drawing) is a latch signal generated when the CCD sensor 120 scans, and when the WRPLS211 comes from the CCD sensor 120 scan to the position b (see FIG. 3) that has the color information after color conversion. This is a generated latch signal.

G. Counter output timing Figure 6 shows the counter in Figure 5 during the prescan cycle.
The output timing of 202 is shown. As shown in the figure, the counter 202 starts counting the synchronization signal HSYNC in synchronization with the rising edge of the synchronization signal VSYNC, and when the count value reaches the sub-scanning count value set in the sub-scanning latch 201,
When the count of the synchronization signal CLK for each pixel is started and the count value reaches the main scan count value set in the main scan latch 200, the RD of the data latch pulse is output according to the mode.
Generates either PLS210 or WRPLS211.

H. Judgment Circuit FIG. 7 shows a judgment circuit 1 which constitutes the color conversion circuit 123 of FIG.
23C shows a circuit configuration. Image data YIN10, MIN20, CIN30 input from the judgment circuit 123C during the actual scan cycle
Determines whether each is image data for which color conversion is designated, and outputs the result as comparison signals YSEL40, MSEL50, CSEL60.

In FIG. 7, 400, 401, 406, 410, 411, 420 are for judging YIN10 image data, and 402, 403, 407, 412, 41
3,421 is for judging the image data of MIN20, 404,
Reference numerals 405, 414, 415, 422 are for judging the image data of CIN30.

Reference numeral 400 is a first comparator that compares the image data YIN10 of the yellow component input during the actual scan cycle with the output of the adder 410 described later, and becomes active (high level) when the output of the adder 410 is large. Numeral 401 is a second comparator which compares YIN10 with the output of the subtractor 411 described later and becomes active when YIN10 is larger. Reference numeral 406 is an AND gate (logical product circuit) that obtains a logical product of both outputs of the first and second comparators 400 and 401, and sets the comparison signal YSEL40 to a high level when both the comparators 400 and 401 are active. That is, assuming that the output of the adder 410 is A and the output of the subtractor 411 is B, the signal YSEL is output from the AND gate 406 when YIN10 is in the range of B <YIN10 <A.

420 is the latch signal RDP generated in the prescan cycle
It is a latch (latch circuit) that stores the input image data YIN10 according to LS. 430 is a switch for giving a certain width to the determination of whether or not to perform color conversion.
The value set by is the adder 410,412,414 and the subtractor 411,41
Supplied to 3,415. The adder 410 adds the image data sent from the latch 420 and the value set by the switch 430 in the actual scan cycle, and outputs the result to the first comparator 400. Similarly, the subtractor 410 uses the switch 4 from the image data sent from the latch 420 in the actual scan cycle.
The value set in 30 is subtracted and the result is sent to the second comparator.
Output to 401.

402 and 404 are first comparators similar to 400 described above, 403 and 405
Is a second comparator similar to the above 401, and 407 and 408 are the above 40
AND gate similar to 6, 412 and 414 are adders similar to 410 described above, 413 and 415 are subtractors similar to 411 described above, and 421 and 42
2 is a latch similar to 420 described above.

Next, the operation of the above-described determination circuit 123C will be described. In the pre-scan cycle, when the CCD sensor 120 reaches the designated position in the area for performing the color conversion previously designated by the digitizer 112, the latch pulse of the RDPLS210 is counted by the counter 202. (See FIG. 6), the data of YIN10 of the yellow component, MIN20 of the magenta component and CIN30 of the cyan component when the latch pulse is generated are simultaneously set in one of the corresponding latches 420, 421 and 422, respectively.

Next, in the actual scan cycle, the yellow component signal of YIN10 is input to the comparators 400 and 401. On the other hand, the yellow component data set in the latch 420 in the prescan cycle and the data set by the switch 430 are input to the adder 410 and the subtractor 411, respectively.
The setting data of the switch 430 is for setting the width of a certain range in determining whether or not to perform color conversion as described above. For example, the density data of YIN10 is 80
_(HEX) and the setting value of switch 430 is 2, adder 410
This data 80 _(HEX) is added to 2 and 82 _(HEX) is added to the comparator 40
Output to 0. At this time, the subtractor 411 has the data 80
Outputs 7E obtained by subtracting 2 from _(HEX) to _(HEX) to the comparator 401.

The comparator 400 compares the yellow component signal sequentially input in the actual scan cycle, YIN10 with the output 82 _(HEX) of the adder 410, and if the added output is larger than YIN10, outputs a high level signal, The other comparator 401 compares the input signal YIN10 with the subtractor output 72E _(HEX) and outputs a high level signal when YIN10 is larger. Also, the AND gate 406
Since the logical product of the outputs of both comparators 400 and 401 is taken, if YIN10 input in the actual scan cycle is between 82 _(HEX) and 7E _(HEX) , the AND gate 406 outputs the comparison signal YSEL40.

Similar to the above, MI sequentially input in the actual scan cycle
N20 and CIN30 are also compared in corresponding comparators 402, 403 or 404, 405 with values based on the data set in latches 421, 422 and switch 430, and latches 421, 422 and switch 430 are compared.
Within the range set by, AND gates 407 and 408 output comparison signals MSEL50 and CSEL60, respectively.

Therefore, if the image data that matches the density of the three colors at the position designated by the digitizer 112 with the constant width designated by the switch 430 is input in the actual scan cycle,
All the comparison signals YSEL40, MSEL50, CSEL60 become active. Therefore, these signals YSEL40, MSEL50, CSEL60 serve as a judgment signal as to whether or not the density area is the designated density area, and when all of these signals become active, color conversion with the color of the other area designated by the digitizer 112 is performed. .

I. Selector Circuit FIG. 8 shows the circuit configuration of the selector circuit 123B which constitutes the color conversion circuit 123 of FIG. The selector 123B is a selection circuit that selects whether to output the color information after color conversion in the actual scan cycle or to output the color information that is actually input as it is (referred to as “through”).
0, 301, 302, latches (latch circuits) 303, 304, 305, and a pair of AND gates (logical product circuits) 306, 307. Further, YIN10, MIN20, CIN30 are color signals of yellow component, magenta component, and cyan component supplied from the image processing circuit. LATCHENB is a latch enable signal that is activated in the prescan cycle and deactivated in the actual scan cycle. YSEL, MSEL, and CSEL are determination signals output from the above-mentioned determination circuit 123C (see FIG. 7) indicating color conversion permission, and these signals YSEL, MSEL, and CSEL are AN.
When input to the D gate 307 and everything becomes active, that gate opens and color conversion is performed.

First, in the prescan cycle, the digitizer 11
When the CCD sensor 120 reaches a position (point b) having color information after color conversion designated in advance by 2, the counter 20
WRPLS211 is output from 2 (see FIG. 6). At this time, since the signal LATCHENB is active (high level), the WRPLS211 passes through the AND gate 306 and latches 303, 304, 30.
The input color signal YIN10 is set to the latch 303, MIN20 is set to the latch 304, and CIN30 is set to the latch 305.

Next, in the actual scan cycle,
YIN10 is input to the selector 300, but when the YSEL40, MSEL50 and CSEL60 color conversion enable signals are not all active, the AND gate 307 does not open, so the selector 300
Passes the input YIN 10 as it is and outputs it to the printer 125 as an output signal (Yout) 11 of the yellow component. YSE
When the L40, MSEL50 and CSEL60 signals are all active, the select terminal S of the selector 300 is turned on by the output of the AND gate 307, and the selector 300 outputs the color-converted yellow component data set in the latch 303. Yout
It is output to the printer 125 as 11, and color conversion is performed by this. The other color components, MIN20 and CIN30, operate in the same manner as YIN10, and color conversion is performed.

In this embodiment, the color conversion process is performed on the signal obtained by reading the original, but the color conversion process can be similarly performed on the color television signal or the color signal in the memory.

EFFECTS OF THE INVENTION As described above, according to the present invention, the color to be converted is detected from the original, the color after conversion is used, and the color equivalent to the color to be converted on the original is the color after the previous conversion. It is configured to be converted to. Therefore, when performing the color conversion processing by designating the area to be color-converted as in the conventional case, even when the color area to be color-converted has a complicated shape that requires complicated processing, the present invention According to this, color conversion can be performed with a simple operation.

Further, the present invention has a configuration in which the position of the desired color that is the color to be converted is specified on the document and the desired color at the specified position is detected from the light obtained by illuminating the document. For example, there is no need for a large-capacity memory for one frame for displaying an image, which is required in the conventional configuration in which an image is displayed on a monitor and a desired color is selected as a color to be converted from the display image. According to
A defect caused by the difference between the reproduced color when displayed on the monitor and the color represented by the actual data depending on the monitor characteristics, that is, even if the color on the monitor is specified as the color to be converted, variations in the color development characteristics of the monitor Thus, there is no disadvantage that a color shift occurs between the color to be designated and the color actually designated on the monitor, and it is possible to perform highly accurate and accurate color conversion.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of an embodiment of the present invention, FIG. 2 is a block diagram showing an overall circuit configuration of an embodiment of the present invention, and FIG. 3 is a plan view showing an operation procedure of the embodiment of the present invention. 4 and 5 are timing charts showing the overall timing of the embodiment of the present invention, FIG. 5 is a block diagram showing the circuit configuration of the latch pulse generation circuit 123A which constitutes the color conversion circuit 123 of FIG. 2, and FIG. 5 is a timing chart showing the timing of the output signal of the latch pulse generation circuit 123A in FIG. 5, and FIG. 7 is a judgment circuit 123 constituting the color conversion circuit 123 in FIG.
FIG. 8 is a block diagram showing a circuit configuration of C, and FIG. 8 is a block diagram showing a circuit configuration of a selector circuit 123B which constitutes the color conversion circuit 123 of FIG. 100 …… ROM, 101 …… RAM, 102 …… CPU, 111 …… Operating section, 112 …… Digitizer, 120 …… CCD sensor, 122 …… Image processing circuit, 123 …… Color conversion circuit, 123A …… Latch Pulse generator circuit, 123B …… selector circuit, 123C …… judgment circuit, 200,201,303,304,305 …… latch, 202 …… counter, 300,301,302 …… selector.

Claims (1)

[Claims] 1. A converted color when performing color conversion processing,
Position specifying means for specifying the position of the desired color on the original included in the original, color generating means for generating a color signal indicating the converted color when the color to be converted is color-converted, and illuminating the original Illuminating means, for detecting a color signal corresponding to the desired color, a position on the document designated by the position designating means,
Storage means for storing a color signal corresponding to the light obtained by illuminating with the illumination means, and an equivalent color to the desired color included in the document based on the color signal corresponding to the desired color stored in the storage means A color image processing device, comprising: a color conversion unit that determines a region and converts the equivalent color region into a color represented by a color signal generated by the color generation unit.