JPH0449629Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is an image scanning color separation device that creates color separation plates for multicolor printing, which is substantially equivalent to color printed matter reproduced by a so-called color scanner. Regarding the color monitor, which displays simulated color images in advance on the color monitor to appropriately set various working conditions of the color scanner, in particular, it is necessary to check the tone of the displayed color image. The present invention relates to a device that displays a frame line having an appropriate width around an image area in a desired reference color.

[Prior Art] Japanese Patent Publication No. 55-10904 (title of the invention "Reference color display device in multicolor image display device") by the present applicant discloses that in a color monitor device for a color scanner, A device is described in which a required reference color area (color patch) is displayed, the tone of a color image surrounding the area is compared with that of the color patch, and the working conditions to be set in the color scanner are determined.

The device of the prior application eliminates a part of the displayed image by erasing the image signal input to the color CRT at the required timing in the horizontal and vertical directions, and also erases the reference color signal in synchronization with the image signal. is generated, a reference color signal is input in place of the erased image signal, and an area of the reference color is displayed in a part of the displayed image.

[Problems to be Solved by the Invention] Since the device of the prior application displays the reference color as a color patch, there is a possibility that the color tone of the displayed image may be misidentified.

In other words, if the area to be checked for color tone occupies a relatively large area, there will not be much of a problem, but if the target color tone area is small and adjacent to other color areas, There is a problem in that a color contrast effect occurs in which the appearance of colors changes due to the influence of the color tones of adjacent areas, making it impossible to recognize accurate color tones and making the condition settings of the color scanner inaccurate.

The present invention improves the drawbacks of the conventional apparatus and realizes a color monitor for a scanner that can perform color correction more easily, quickly, and accurately.

[Means for solving the problem] The present invention for achieving the above object is configured as follows.

A color image equivalent to the reproduced image is displayed on a color monitor based on a recording color separation signal obtained by performing color correction on the color separation image signal obtained from the color original image, and a reference color cursor is displayed in the color image. In a color scanner monitor device for checking the tone of a color image, the cursor is a cursor frame consisting of a window formed in the center and a periphery formed around the window; a positioning means for moving the cursor frame within a color monitor screen; a frame setting means for setting an outer circumferential dimension and an inner circumferential dimension of the cursor frame;
a color setting means for setting a reference color by referring to a color hexagon chart; and a color setting means for composing the cursor frame and a color image and displaying the same on a color monitor screen, and in the area of the cursor frame, color setting means for setting the cursor frame for the reference color. compositing means for displaying images with priority.

[Operation] Position the window of the cursor frame whose periphery is set as the reference color by referring to the color hexagon chart to the correction target area of the color image displayed on the color monitor screen, and set the area to the cursor frame of the reference color. By surrounding it with , the area to be corrected is isolated from other areas of the color image, and the tone of the area can be easily compared with the reference color at the periphery of the cursor frame, thereby achieving accurate tone recognition.

[Example] First, the basic idea of the present invention will be explained with reference to FIGS. 2 and 3.

FIG. 2 shows a state in which a cursor frame 2 of a reference color for color correction is displayed on a part of the screen of the color scanner monitor 1 displaying a monitor image. Display the dot percentage values of each color of yellow (Y), magenta (M), cyan (C), and black (K) displayed in this cursor frame 2 at an appropriate location on monitor 1 (at the bottom in the case shown).
is displayed.

As shown in FIG. 3, the cursor frame 2 is a rectangular pattern consisting of a window formed in the center and a peripheral edge (hatched area) formed around the window.
By setting the outer circumferential dimension (n, s), inner circumferential dimension (m, r), and position (N, M) of the center point (O) to desired values, the cursor frame 2 of the desired dimension is displayed on the monitor screen. It can be moved and displayed at any position. This size and position display is performed using H gate signals and V gate signals synchronized with the horizontal and vertical scanning of the color monitor.
This is done by switching between the image and the cursor frame indicating the reference color at the H/L level of the gate signal and at the required timing as shown in the third figure. Details of this specific means will be described later.

Next, FIG. 1 is a block diagram showing the configuration of an apparatus according to an embodiment of the present invention.

An original image drum 3 equipped with a color original image 4 to be scanned
and a recording drum 5 on which a recording photosensitive material 6 is mounted are rotated by a motor 8 via a common rotation shaft 7. Attached to the other end of the rotating shaft 7 is a rotary encoder 9 that generates a number of clock pulses proportional to the rotation angle of the drum.

There is a pick-up head 10 on the original drum 3 side.
However, an exposure head 13 is disposed on the recording drum 5 side so as to be movable in the axial direction of the drum, and feed screws 1 are driven by motors 11 and 14, respectively.
2 and 15.

The pick-up head 10 photoelectrically scans the color original image 4 and outputs R, G, and B analog color separation signals. This color separation signal is converted into an A/D converter that performs analog/digital conversion using a timing signal output from the timing circuit 16 on the original image scanning side based on the clock pulse from the rotary encoder 9.
The D converter 17 converts each pixel into a digital signal, which is written into the frame memory 19 by the selector 118. At this time, the input thinning circuit 2
0, pixels in the main scanning direction and the sub-scanning direction are thinned out and stored at an appropriate pitch. Means for temporarily storing such color separation signals is disclosed in Japanese Patent Publication No. 59-822 and Japanese Patent Publication No. 62-4648 filed by the present applicant.

Then, it was written into the frame memory 19.
The RGB color separation signals are read out and input to the color correction circuit 21, where they are converted into corrected color separation signals of yellow (Y), magenta (M), cyan (C) and black (K) for recording a duplicate image. do. This digital color correction means is shown in Japanese Patent Publication No. 60-52430 by the present applicant. When color correction is performed using an analog circuit, an appropriate D/A conversion circuit or A/D conversion circuit may be provided.

When scanning and recording a duplicate image, the image signal from the pick up head 10 passes through the A/D converter 17, the selector 118, the color correction circuit 21,
Next, the corrected YMCK color separation signal is converted by the selector 222 into an image signal matching the desired reproduction image size by the magnification conversion circuit 23, and further converted into a halftone image signal by the dot generator 24. , is input to the recording head 13, and the photosensitive material 6 mounted on the recording drum 5 is exposed and scanned to record a duplicate image. Magnification conversion circuit 23
The dot generator 24 is controlled based on timing pulses generated by the exposure scanning side timing circuit 25.

The present invention is to display a color image substantially equivalent to the duplicated image on the monitor prior to this exposure recording scan, and in that case, the YMCK color separation signal is switched to the monitor side using the selector 222 and output. , through the output thinning circuit 28, YMCK/
The RGB conversion circuit 26 converts the signal into an RGB signal for display on a color monitor, and writes it into the frame memory 27. The frame memory 19 has a capacity to store a plurality of images, and an output decimation circuit 32 performs appropriate decimation on one image, and writes the resulting decimated image into the frame memory 27. The images can be displayed side by side. This operation is controlled by a timing pulse output from the color monitor side timing circuit 29. Note that a method for converting YMCK color separation signals into RGB signals for display on a color monitor is known, for example, from Japanese Patent Publication No. 1983-1999 by the applicant.
No. 28521.

The RGB signals stored in the frame memory 27 are
A color image that is sent to the color monitor 31 via the synthesis circuit 30 and is substantially equivalent to a duplicate image based on the color-corrected color separation signals created by the color correction circuit 21 is displayed on the monitor 31.

When displaying this monitor image, a cursor signal for displaying a cursor frame in a desired part of the screen is separately generated using the cursor generation circuit 32 and the operation unit 34 attached thereto, and the cursor signal is generated in the synthesis circuit 30.
Combine with RGB image signal.

Note that the operation section 34 and the cursor generation circuit 32
includes a positioning means, a frame setting means, and a color setting means according to the present invention, and the composition circuit 30 corresponds to the composition means according to the present invention. Specific configurations of these will be described later.

FIG. 4 is a block diagram showing a circuit for generating a cursor signal for displaying a cursor frame at a desired position and arbitrarily setting the sizes of the inside and outside of the cursor frame, and FIG. is a synthesis circuit 3 for displaying the color tone of the cursor frame in a desired reference color.
FIG.

In the circuit shown in FIG. 4, one set is provided in the cursor generation circuit 32 for each of the horizontal scanning direction and the vertical scanning direction, and since both have the same configuration, the horizontal scanning direction will be explained here. Note that symbols in parentheses in the drawings indicate the case in the vertical scanning direction.

The counter 41 determines the center position of the cursor frame, and is used by the color monitor side timing circuit 3.
The specified center position is determined by the output of an AND circuit 44 which receives the clock signal from 3 and a signal indicating the desired center position of the cursor frame by the operator.
It is output as a coordinate value (N) corresponding to the number of pixels on the monitor screen.

The counter 42 determines the outer circumferential dimension (n) of the cursor frame, and similarly outputs a numerical value corresponding to the number of pixels of the outer circumferential dimension (n) based on the number of clocks output from the AND circuit 45 according to instructions from the operator. do.

The counter 43 determines the inner circumference of the cursor frame, that is, the dimension (m) of the window, and similarly, based on the number of clocks output from the AND circuit 46,
A numerical value corresponding to the number of pixels of the window dimension (m) is output.

The output (N) of the counter 41 is output to the selector 59
through the next stage's four adders/subtracters~47~5
0, the output n of the counter 42 is input to the first and second adder/subtractors and 47, 48, and the output (m) of the counter 43 is input to the 3
It is input to the th and 4th adder/subtractor and 49 and 50.

The adder/subtractor 47 calculates N-1/2・n, the adder/subtractor 48 calculates N+1/2・n, the adder/subtractor 49 calculates N-1/2・m, and the adder/subtractor 50 calculates N+1/2・m. be done. That is, the adder/subtractor 47
48 calculates the coordinate value of the left side of the outer periphery of the cursor frame, and 48 calculates the coordinate value of the right side.
9 calculates the coordinate value of the left side of the window, and 50 similarly calculates the coordinate value of the right side.

These four types of coordinate values are input to the next-stage counters 51 to 54, respectively, and these counters count the number of clocks corresponding to the input coordinate values and output signals respectively. It is sent to OR circuits 55 and 57.

The first OR circuit 55 includes four counters.
All output signals from the counter and are input to the second OR circuit 57, and output signals from the counter and the counter are input to the second OR circuit 57. The output of the OR circuit 55 is J/
The output of the OR circuit 57 is input to a J/K flip-flop 58. As a result, the first J/K flip-flop 56 is switched to H/L at a timing corresponding to each coordinate value of the outer periphery of the cursor frame and the window, and the second J/K flip-flop 58
is switched at a timing corresponding to the coordinate value of the outer circumference of the cursor frame.

Figure 6 is a timing chart showing this output state. The numbers attached to each graph line in the lower row indicate the output state of each circuit element with the corresponding number, and the number of H clocks in the horizontal scanning direction is counted. , the output of the first J/K flip-flop 56 is switched to H/L by the pulse signal outputted from the counters ~51-54 by the output of each adder/subtracter, and the output of the first J/K flip-flop 56 is switched to H/L,
In the J/K flip-flop 58, two pulse signals from the counter indicate the timing of switching at the outer periphery of the cursor frame.

The above is about the horizontal scanning direction, but the vertical scanning direction is also processed in the same way, and by combining both with a gate circuit composed of an OR circuit 73 and an AND circuit 74 shown in FIG. 5, which will be described later. , a cursor frame signal for displaying a cursor frame forming a desired window can be output.

In FIG. 4, the selector 59 placed on the output line of the counter 41 and the coordinate conversion circuit 60 that sends input signals to it are used to select the color tone to be displayed in the cursor frame. , these will be described later.

Next, FIG. 5 shows a color generation circuit that outputs the reference color to be displayed in the cursor frame, a circuit that synthesizes the image signal and the cursor frame signal from the frame memory 27, and a circuit that generates the reference color color patch signals R, G, and B. and a synthesis circuit 30 that synthesizes and displays the reference color generated in the cursor frame within a color image.

Four variable resistors 61 to 64 are incorporated into the operating section 34. The resistance values of the variable resistors 61 to 64 are the halftone dot % in each color separation of YMCK.
In addition, the set halftone dot percentage value is displayed on the monitor screen by known means (not shown) as shown in the second figure.

A voltage is applied to each variable resistor 61 to 64, and the voltage obtained from the sliding terminal is applied to each A/D.
Quantized by converters 65 to 68, YMCK/
It is input to the RGB conversion circuit 69 (hereinafter referred to as LUT). YMCK/RGB conversion circuit 69 is YMCK
It converts a signal into an RGB signal, and for example, the means disclosed in Japanese Patent Publication No. 54-38521 may be used. These RGB signals are input to selectors 70, 71, and 72 at the next stage.

On the other hand, among the two types of gate signals in the horizontal scanning direction and the vertical scanning direction outputted from the fourth illustrated device, the gate signal for the window, H gate signal 1 and V gate signal 1 are outputted to the OR circuit 73. The output is inputted to the AND circuit 74 together with the horizontal and vertical gate signals for the remaining peripheral parts, the H gate signal 2 and the V gate signal 2, and the output of the AND circuit 74 is used to select the three selectors 70 to 70. 72.

A color image signal to be processed is inputted from the frame memory 27 to the other input terminal of the selectors 70 to 72, and the selectors 70 to 72 are input by each gate signal.
By the switching operation 72, a cursor frame is displayed in a desired area of the color image displayed on the screen of the color monitor.

Further, a selector 75 is arranged at a suitable position on the input line of the color image signal from the frame memory 27,
A color hexagon chart is generated for reference when setting the reference color from the graphic memory 35, and by switching the selector 75 by an operator's operation, the screen displayed on the color monitor 31 is changed to the color image to be processed. or a color hexagon chart for setting the reference color.

FIG. 7 shows an example of a color hexagon chart. A color hexagon chart is stored in the graphic memory 35, and this chart is read out and the RGB color separation signals are inputted to the selectors 70 to 72 via the selector 75, and the chart is displayed on the color monitor 31. Then, place the desired color in the color hexagon chart.
Display cursor 2.

In this case, by converting the values of Yc, Mc, and Cc into values corresponding to the outputs N and M of the counter 41 using the coordinate conversion circuit 60 shown in FIG. Display.

The transformation in the coordinate transformation circuit 60 is performed as follows.

In the minimum value selection and color separation circuit 76 shown in FIG. 5, the minimum value is selected from Y, M, and C, which are the set values of the variable resistors 61 to 63, and the following equations are calculated.

Yc=Y-min Mc=M-min Cc=C-min One of Yc, Mc, and Cc is always "0".

These Yc, Mc, and Cc are input to the coordinate conversion circuit 60, and the cursor frame 2 shown in FIG.
Convert to the center coordinate values (X _h , Y _h ). When the coordinate values of the center of the hexagon chart are (X _p , X _p ), it is expressed as X _h = X _p + ΔX y _h = Y _p + ΔY.

Here, when ()Cc=0 ΔX=Mc cos30°, ΔY=Yc−Mc sin30° ()When Yc=0 ΔX=Mc cos30°−Cc cos30° Δy=Mc sin30°+Cc sin30° ()Mc= 0, ΔX=−Cc cos 30°, ΔY=Yc−Cc sin 30°, and by applying these k values to the above equation, it can be converted to (X _h , Y _h ) in the orthogonal coordinate system.

This (X _h , Y _h ) value is output from the coordinate conversion circuit 60 and sent to the counters 47 to 50 via the selector 59.
, and displays the cursor frame 2 shown in FIG. 7 at a desired position.

In this case, the cursor frame 2 can be created by appropriately adjusting the values of the outputs m and r of the counter 43 and the values of the outputs n and s of the counter 42 in FIG. 2 can be displayed.

In this way, the color hexagon chart is displayed on the monitor, and the cursor frame 2 is set to the variable resistors 61 to 64.
Displayed at the required position on the color hexagon chart with the color tone determined by the setting value. Next, the screen of the color monitor 31 is switched to a color image to be processed.

Then, by adjusting the output values of the counters 41 to 43, the cursor frame 2 forming a window of a desired size is displayed at a desired location on the displayed color image. At this time, the color tone of the cursor frame 2 is maintained at the color tone set by the variable resistors 61 to 64. Therefore, when selecting the color tone to be displayed on the cursor, first select the color tone that should be duplicated in the target color image area in the color hexagon chart, and make sure that the color tone of the cursor matches it. By setting this, it is possible to accurately display the color tone of the cursor frame as the desired reference color.

In this way, the desired portion of the color image resulting from color separation of the color original image by the color scanner is displayed on the color monitor 31, surrounded by the cursor frame of the reference color, so that it is possible to check whether various work condition settings in the color scanner are appropriate or not. can be checked reliably and easily.

[Effects of the invention] (1) When displaying the cursor frame of the reference color for color tone check on a color monitor that displays a color image equivalent to the printed matter as a result of color separation work using a color scanner, only the image area to be checked is displayed. Since the color is displayed in the window of the cursor frame and the periphery of the cursor frame is used as the reference color, the influence of color contrast effects caused by other surrounding tones is removed, allowing accurate color tone judgment.

(2) Since the reference color to be displayed on the periphery of the cursor frame is selected by referring to the color hexagon chart, it is possible to display a reference color that appropriately corresponds to the human color perception information of brightness, saturation, and hue.

(3) Therefore, color tone contrast can be performed accurately and easily.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a device according to an embodiment of the present invention, FIG. 2 is a diagram showing a cursor frame displayed on a color monitor, and FIG. 3 is a diagram showing a cursor frame and a gate signal for displaying it. Figure 4 is a block diagram of the cursor generation circuit, Figure 5 is a block diagram of the synthesis circuit, Figure 6 is a timing chart showing the gate signal generation timing, and Figure 7 is a color hexagon chart for selecting a reference color. This is an example. 1...Color monitor, 2...Cursor frame, 3...
...Original image drum, 4...Color original image, 5...Recording drum, 6...Photosensitive material, 7...Drum rotation shaft, 8
... Drive motor, 9 ... Rotary encoder, 10 ... Pickup head, 13 ... Exposure head, 11, 14 ... Motor, 12, 15 ...
...Feed screw, 19...Frame memory, 21...
...Color correction circuit, 26...YMCK/RGB conversion circuit, 27...Frame memory, 29...Color monitor side timing, 30...Composition circuit, 31
...Color monitor, 32...Cursor generation circuit,
33...Color monitor side timing, 34...
Operation unit, 35...Graphic memory.

Claims (1)

[Claims for Utility Model Registration] Displaying a color image equivalent to a reproduced image on a color monitor based on a recording color separation signal obtained by performing color correction on a color separation image signal obtained from a color original image, In a monitor device for a color scanner, which displays a reference color cursor on the screen to check the tone of a color image, the cursor is moved between a window formed in the center and a peripheral area formed around the window. a cursor frame, a positioning means for moving the cursor frame within a color monitor screen, a frame setting means for setting an outer circumferential dimension and an inner circumferential dimension of the cursor frame, and a color tone to be displayed on the periphery of the cursor frame. ,
a color setting means for setting a reference color by referring to a color hexagon chart; and a color setting means for composing the cursor frame and a color image and displaying the same on a color monitor screen, and in the area of the cursor frame, color setting means for setting the cursor frame for the reference color. A monitor device for a color scanner, comprising: composition means for displaying images with priority.