JPH02220865A - Digital color copying machine - Google Patents

Abstract

PURPOSE:To obtain a mosaic monitor mode for early regulating a desired color regulation by providing color correction coefficient calculating means for calculating color correction coefficients of a plurality of stages used for calculating color correction by calculating with a reference value, and reference value setting means for setting the reference value for calculating the color correction coefficient of desired image selected by a user for calculation of next color correction. CONSTITUTION:In a process of mosaic monitor outputting, reading conditions of content of a memory 401 of a noting area are set, and color correction coefficients yi, mi, ci (i=0, 2) are calculated with reference values y1, m1, c1 of color correction coefficient and regulating value (a) as a basis. For example, the value (a) is increased or decreased for the reference value to set the coefficient to three stages. Then, when a user's desired image is selected from the mosaic monitor image on a display 84, color correction coefficient responsive to the selected image is set. Then, when the selected coefficient is set to the reference value, the set selected values y1, m1, c1 are stored as the reference values. The user presses a mosaic monitor selection key 78 to start it when the mosaic monitor image is desired to be printed with the set reference value as a basis.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a digital color copying machine having a mosaic monitor function.

(Prior Art) A digital color copying machine includes a reading section that reads a document using a color image sensor and converts it into a printout signal, and a printer section that prints an image on paper using electrophotography in response to this printout signal. When printing out multiple colors, the reading section reads the document and the printer section prints the image on the same paper in a field-sequential manner for each color.

The reading section generally includes a masking circuit and generates a signal that is color-corrected in accordance with the printing characteristics of an output device (such as a printer).

Although a color-corrected image is printed in this way, it is difficult for the masking circuit to suppress the color difference between the original and the copy to a very small value for all colors on the original. Therefore, when a copy is copied as an original, the color tone may be significantly different from the original.

However, in a certain limited chromaticity range, color adjustment (
If you perform color balance), the change in color tone can be kept relatively small.

However, in the past, color adjustments were made by copying each color adjustment and cutting and trying, and the number of adjustments was
Scanning for each printed color is repeated, which is a waste of time and cost.

Therefore, in another application, the present applicant proposed a color adjustment selection method (hereinafter referred to as a mosaic monitor) that reduces the time and cost required for color correction. In this method,
The specific area setting means sets an area (attention area) that includes a part (for example, a face) on which the user particularly wants to place emphasis on color reproduction, and image data of the attention area is stored in the image memory means. Next, color correction is performed on the image data read out from the image memory means at various predetermined different color correction levels, and these are displayed at different positions on the same sheet of paper.
Printed during the printing process. The user selects the image closest to the color of the original image from among the images of multiple areas of interest in different tones (mosaic monitor images) printed on a single sheet of paper.
Or select an image with the user's favorite color. Next, the entire document is copied based on the color correction level value of the selected image.

In this way, a copy with the color adjustment desired by the user can be easily obtained.

(Problems to be Solved by the Invention) The mosaic monitor allows the user to easily make a copy of the desired color adjustment.

However, if, for example, there is no image with the desired color adjustment within the range of the mosaic monitor image, the user may
The mosaic monitor must be operated repeatedly at different color correction levels until a satisfactory color tone is obtained. in this case,
Scanning for image reading of the region of interest on the document must also be performed again. Particularly when it comes to faithfully reproducing skin tones in portraits, color adjustments are often repeated many times, so it is desirable to be able to make adjustments efficiently.

In addition, color copying machines may experience changes in color tone over time. Due to this change over time, the initially appropriate color adjustment level substantially changes. Preferably, this change in color tone over time can also be adjusted at the user level.

SUMMARY OF THE INVENTION An object of the present invention is to provide a digital color copying machine equipped with a mosaic monitor mode that allows quick adjustment to desired color adjustments.

(Means for Solving the Problems) A digital color copying machine according to the present invention prints multiple images at different positions on the same sheet of paper by performing different color correction calculations on image data of a certain area in a document image. death,
Equipped with a mosaic monitor mode in which the user selects a desired image from among these multiple images I: In a digital color copying machine, multi-level color correction coefficients used in color correction calculations are calculated by performing predetermined calculations on standard values. a color correction coefficient calculating means; a standard value setting means for setting the color correction coefficient of the desired image selected by the user as a standard value for the next color correction calculation; and after the standard value setting by the standard value setting means, The present invention is characterized by comprising an instruction means for instructing printing of the plurality of images again.

(Function) In a digital color copying machine, a print signal (multi-value) corresponding to each print color (for example, yellow, magenta, cyan) is generated from R, G, and B image signals (multi-value) read by an image sensor. Y, M, and C are required. In the color correction calculation, the product of this print signal and the color correction coefficient is calculated. This adjusted print signal is binarized and printed.

In mosaic monitor mode, each print color has multiple levels (
For example, three levels of color correction coefficients are used. This color correction coefficient is obtained by performing a predetermined calculation on the standard value by a color correction coefficient calculating means. For example, a predetermined adjustment value is added to or subtracted from the standard value in 3 stages. The color correction coefficient of is determined.

The standard value is set by the standard value setting means to set the color correction coefficient of the desired image (that is, the desired color tone) selected by the user from among the multiple images printed in the mosaic monitor mode as the standard value for the next color correction calculation. Set.

(Embodiments) Hereinafter, embodiments of the present invention will be described in the following order with reference to the accompanying drawings.

(a) Configuration of digital color copying machine (b) Mosaic monitor (c) Picture setting circuit (d) Registered image memory circuit (e) Flow of copy control related to mosaic monitor mode Particularly relevant to the present invention are ( Section b), Section (C) and (
This is the part related to standard value setting (Figure 11) in section e).

(a) Structure of Digital Color Copying Machine The digital color copying machine according to the present invention includes a reading section that reads a document using an image sensor and converts it into a printout signal, and an electrophotographic method to print paper on paper in response to this printout signal. It consists of a printer section that prints images. When printing out multiple colors, the reading unit reads the document for each color, and the printer unit prints the image on the same paper in a field-sequential manner.

FIG. 1 shows the overall configuration of a digital color copying machine according to an embodiment of the present invention.

The scanner IO includes an exposure lamp 12 that irradiates the original, a rod lens array 13 that collects reflected light from the original, and
The scanner 10 is equipped with a close-contact type COD color sensor (image sensor 4) that converts the collected light into an electrical signal.When reading a document, the scanner 10 is driven by a motor 11 and moves in the direction of the arrow, and is placed on the platen 15. The placed original is scanned.The image of the original surface illuminated by the light source 12 is CC
The D color sensor 14 performs photoelectric conversion.

R and G obtained by the CCD color sensor 14.

The B electrical signal (multi-value) is converted by the signal processing unit 20 into a print output signal (binary) of yellow, magenta, cyan, or black, and is stored in the buffer memory 30. In the print head unit 31, the buffer memory 3
According to the print signal from 0, the LD drive circuit 32 blinks the semiconductor laser (LD) 33 (see FIG. 2).

As shown in FIG. 1, the laser beam generated by the semiconductor laser 33 exposes the photoreceptor drum 41, which is rotated, through a reflecting mirror 37. As a result, an image of the document is drawn on the photoreceptor of the photoreceptor drum 41. The photosensitive drum 41 is exposed to an eraser lamp 42 before being exposed to light for each copy.
, is irradiated by a charger 43 , and is further irradiated by a supply eraser lamp 44 . When exposed in this state, a #electronic image is formed on the photoreceptor drum 41. Only one of the yellow, magenta, cyan, and black toner developers 45a to 45d is selected to develop the electrostatic latent image on the drum. The developed image is transferred by a transfer charger 46 to paper wound on a transfer drum 51.

Usually, this printing process is repeated for yellow, magenta, cyan, and black. At this time, the scanner 10 synchronizes with the operation of the photosensitive drum 41 and the transfer drum 51.
repeats the scanning operation.

Thereafter, the paper is separated from the transfer drum 51 by operating the separation claw 47, passed through the fixing device 48, fixed, and discharged onto the paper discharge tray 49.

Note that the paper is fed from a paper cassette 50, and its leading edge is chucked by a chucking mechanism 52 on a transfer drum 51 to prevent misalignment during transfer.

Next, the signal processing section 20 that processes the output signal of the CCD color sensor 14 and outputs a binary image signal will be explained with reference to FIG.

When outputting a normal image, the image signal photoelectrically converted by the CCD color sensor 14 is converted into image density by the log amplifier 21, and then converted into a digital value by the A/D converter 22 (
multivalued). The R, G, and B image signals subjected to multi-value conversion are subjected to shading correction in a shading correction circuit 23. In mosaic monitor mode etc.
The shading corrected signal is stored in the registered image memory circuit l. When outputting a normal color image, the registered image memory circuit 1 is canceled and the shading-corrected signal is sent to the masking processing circuit 24.

In the above processing, the three colors R and GlB are processed in parallel.

Next, the masking processing circuit 24 generates a signal for one of the printing colors (yellow, magenta, cyan, or black) according to the characteristics of the printing toner from the three human input signals in order to perform printing in the field sequential manner. A control signal from the CPU 25 determines which print color a signal is to be generated. When changing the color adjustment in the mosaic monitor mode or the normal mode, the print signal is subjected to color correction in the image tone setting circuit 2. In the case of a normal image, the image tone setting circuit 2 is canceled and no color correction is performed.

The electric magnification circuit 26 electrically processes the signal from the masking processing circuit 24 or the image level setting circuit 2 to electrically change the magnification in the main scanning direction, and the method thereof is well known. The explanation will be omitted here. On the other hand, variable magnification in the sub-scanning direction can be realized by varying the speed of relative movement between the original and the scanner IO.

The halftone processing circuit 27 binarizes the signal from the electric scaling circuit 26 to generate a binary pseudo halftone signal, and sends it to the buffer memory 30. The LD drive circuit 32 drives the semiconductor laser 33 in response to the pseudo halftone signal from the buffer memory 30 to emit a laser beam.

In addition, clock generation vI! 28 generates a horizontal synchronizing signal H5ync and a clock signal CKA for synchronizing the reading of the CCD color sensor 14 and the image data processing of each circuit. Further, the sub-scanning clock generator 29 for variable magnification is
In response to a signal from the PU 25, a sub-scan clock for variable magnification, which is an interrupt signal to the registered image memory circuit l, is generated.

Note that the CPU 25 transmits and receives signals to and from the operation panel (see FIG. 4). In addition, signals are sent and received to and from a printer control section (not shown) that controls the printing operation, but since this is the same as in the prior art, the explanation will be omitted.

In the signal processing section 20, image data is processed at the timing shown in FIG. Here, horizontal synchronization signal H5
ync and clock signal CKA are supplied by clock generator 28
・R, G from the CCD color sensor 14
, B flow serially in synchronization with the clock CKA (in the figure, the numbers of the image data indicate addresses in the main scanning direction). Every time the horizontal synchronization signal H5ync is generated, line n in the main scanning direction is updated. That is, the scanner IO has advanced by a unit distance in the sub-scanning direction.

This digital color copying machine is equipped with a color adjustment function called a mosaic monitor and a superimpose function.

Both functions require a memory to store image data, and since they have many things in common in image processing, there is a registered image memory circuit 1 for image registration/reading, and an image tone setting circuit 2 for color adjustment.
Both functions are realized by being controlled by the CPU 25. Note that the superimpose function is disclosed in another application by the present applicant, so detailed explanation will be omitted.

FIG. 4 is a diagram showing the arrangement of various keys on the operation panel 70 provided on the top surface of the copying machine.

The operation panel 70 includes a print start key 71 for starting the copying operation and an interrupt j-7 for specifying interrupt copying.
2. Clear stomp key 73, all reset key 7
4. Numeric keypad 75, set key 76, cancel key 7
7. Various function keys 78-81. Jog dials 82 and 83 are provided for setting areas, which will be described later, and a display section 84 consisting of a liquid crystal display for displaying a document image and various messages for setting areas is provided. Here, function key 78°79.80
are a mosaic monitor selection key, a superimpose mode selection key, and a density correction key, respectively.

Setting of areas such as the area of interest in the mosaic monitor mode, which will be described later, is performed as follows. For example, when setting an area of interest, place the original on the platen 15 as shown in Figure 5.
By placing the document on the document and performing a preliminary scan with the scanner 10, the document area HD
The original image is roughly displayed. Vertical and horizontal direction lines LPY
, LPX is the center of area EA. When the jog dials 82 and 83 are operated, these indication lines move left and right or up and down, respectively, thereby defining the area EA, and pressing the set key 76 sets the area of interest.

(b) Mosaic monitor The mosaic monitor is realized by a registered image memory circuit (see section (d)) 1 that stores the area of interest, and an image adjustment circuit (see section (C)) 2 that performs color adjustment in the printing process. be done.

When function key 78 is pressed on operation panel 70, mosaic monitor mode is selected.

A mosaic monitor is a system in which the user specifies the area of interest for which the best color reproduction is desired, and the image of the area of interest is simultaneously printed in various tones on the same paper. This is a color adjustment selection method in which the optimum color tone is selected from a mosaic monitor image (referred to as a mosaic monitor image) and the color tone is monitored so that the optimum color adjustment can be obtained from the mosaic monitor image.

In the mosaic monitor mode, the user first performs a preliminary scan of the document, and then scans the display section 84 of the operation panel 70.
The user looks at the preliminary scanned document image displayed in , and sets the area of interest (for example, the shaded area in FIG. 5) where the color adjustment is most desired. Corresponding to this, the registered image memory circuit 1
In the next scan, only the image data (3) corresponding to the setting value of the region of interest is stored in the memory. Note that the upper limit of the size of the region of interest is set in accordance with the storage capacity of this memory.

Next, the image tone setting circuit 2 generates print data I'-kI for printing images of various tones on the same sheet of paper from the image data E read out from the registered image memory circuit l and turned into print color data by the masking processing circuit 24. (k −Ky, Km, Kc
) occurs. Here, Ky, +n.

Kc is a color correction coefficient for yellow, magenta, and cyan, respectively. FIG. 6 shows an example of the output format. In this example, cyan (C), magenta (m),
Three types of color correction coefficients Ky” for the three printing colors of yellow (y)
y-, Km-n+,, Kc-a, (i= O, l.

2) to output 3×3×3-27 types of images.

Here, the color correction coefficient CI + m l +
V l represents a standard coefficient of color adjustment. On the other hand, “0”
, '2'' color correction coefficient Co+Ino+Yo; c
2+ll12+y! are the standard coefficient CI +
A coefficient smaller than m l + V l and a coefficient larger than m l + V l are obtained by performing a predetermined calculation on the standard color correction coefficient c + + m l + Y l.

In this example, the color correction coefficients c, , m, , y, (i=
0, 2)ll is the standard value CI + m + of the color correction coefficient for each print color
+'l It is obtained by subtracting and adding a predetermined color correction adjustment value a to l.

Based on this calculation, the color correction coefficient is set as follows.

'! o"VI a y, ← Y+ + a mo ← m -a m2 ← J + a C・ ← C, -a C2 ← C, +a From the 27 types of output images shown in Figure 6, the user can select the optimal Normally, this will exit mosaic monitor mode.

By the way, in order for the user to specify an image to be selected from among the mosaic monitor images GM, for example, the operation panel 70
The function keys 78 to 81 may be operated in accordance with the message displayed on the display section 84.

Alternatively, the image block shown in FIG. 6 may be displayed on the display section 84, and the coefficients may be selected by specifying the block coordinates using the function keys or numeric keys.

Next, the document is read again and the image is printed in the set color tone.

On the other hand, the feature of the present invention is that when you look at the mosaic monitor image and there is no image with the desired color adjustment, you can select the image closest to your desired color adjustment (Fig. 11 861), and then re-mosaic the monitor using that image. The image can be printed (YES in 393 in FIG. 11). In other words, even after printing the first mosaic monitor image, the color correction coefficient of the selected image is changed to the standard color correction value Yl without immediately exiting the mosaic monitor mode.
+lll1+c1 (Fig. 11 392),
Other color correction coefficients are determined based on this standard value, and the mosaic monitor image is printed again.

Also, the reference value changed in this way may be set as the initial value for the next mosaic monitor (
Figure 11 5lll). In this way, the color correction coefficients of the image that faithfully reproduces the original in the mosaic monitor image can be used for the next printing, so that, for example, changes in color adjustment over time can be adjusted at the user level.

(c) Picture setting circuit FIG. 7 is a circuit diagram of the image tone setting circuit 2.

The image tone setting circuit 2 is a circuit installed at the next stage of the masking processing circuit 24 for performing color correction (color adjustment) of a mosaic monitor image.

The masking processing circuit 24 converts the image signals of three colors R, G, and B into image signals (print signals) Y for printing corresponding to each print color of yellow, magenta, cyan, and black.
, M, C, and K, and outputs the converted image signal to the image tone setting circuit 2.

As is well known, the original image signals R,G.

The conversion formula for converting from B to print signals Y, M, and C is expressed as follows.

Each of the conversion coefficients a0° to a is preset to an appropriate value based on theory and experiment so that an image with a color as close as possible to the original image is printed.

Color adjustment in the image tone setting circuit 2 is performed using Yl -K for each print signal Y, M, C obtained by the above calculation.
YXY Mr -KmXM C, w KcXC is calculated and the adjusted print signals Y, , M, , C are obtained.

It is to obtain. Here, Ky, Km, and Kc are color correction coefficients for yellow, magenta, and cyan, respectively.

Note that the black print signal is output only from pixels that are printed in all three print colors of Y, M, and C. Also, no color adjustment is necessary.

In mosaic monitor mode, as illustrated in Figure 6,
A different set of color correction coefficients is provided for each block.

That is, the readout area specified by P o (xo, yo) and P + (X+, y+) is divided into blocks of 3 columns in the main scanning direction X and 9 rows in the sub scanning direction Y, and for each division Different combinations are set. In that case, the coefficient xy of Y (yellow) does not change in the sub-scanning direction Y, but
The coefficient Km of M (magenta) does not change in the main scanning direction X, but changes to 1 in the sub-scanning direction Y.
mar ll1t+ mz+me, ml for each block
..., and the coefficient Kc of C (cyan) does not change in the main scanning direction, but changes every 3 blocks in the sub-scanning direction.
+C++Ct.

Therefore, in the mosaic monitor mode, the image tone setting circuit 2 sets color correction coefficients for each block of the mosaic monitor image for each print signal Y, M, and C as described above, and outputs the adjusted print signal. Output.

In the image level setting circuit 2, a multiplier 301 executes calculations to obtain the above-described print signals Y, , M, , C,. Here, in order to set three coefficients in the main scanning direction in the mosaic monitor mode, three latches 302 and 30
A latch circuit 305 consisting of 3.304 is provided, and coefficients output from the CPU 25 are set in these latches 302 to 304. This 3
The coefficients are values corresponding to three blocks in the main scanning direction. Every time the sub-scanning clock for scaling is input to the CPU 25 as an interrupt signal, the interrupt processing (Fig. 13(a)
), (b)) is performed, and each time the CPU 25 advances by one block in the sub-scanning direction, the CPU 25 outputs a latch signal to the image level setting circuit 2, and latches 302, 303, 304 is latched.

Latch circuit 305 consisting of three latches 302 to 304
The reason for providing this is that in the main scanning direction, the coefficient change cycle is short and it is difficult to set the coefficients in real time by the CPU 25 in terms of speed.

In the above registered image memory circuit l, the image memory 401
The overflow signal X in the main scanning direction generated when reading is input to the first selection signal generation circuit 311, and
The selection signal generation circuit 311 outputs a signal for the selector 306 to sequentially selectively switch each of the latches 302 to 304 each time the overflow signal X is input (for each block). The selector 312 transmits the output S21 of the first selection signal generation circuit 311 to the selector 306 in the mosaic monitor mode.

The selector 306 selects the latch circuit 3 in response to the signal S21.
The coefficients latched in 05 are selectively and sequentially sent to the multiplier 301 block by block.

On the other hand, in the registered image memory circuit l, the image memory 401
Occurs when reading t; Over 70- in the sub-scanning direction
The signal Y is input to the selector 313, and the selector 313 transmits it to the latch circuit 305 in the mosaic monitor mode.

As a result, each time the overflow signal Y is output, the latch circuits 302 to 304 latch and update the set of color correction coefficients output from the CPU 25. Therefore, when the block changes in the sub-scanning direction, the set of color correction coefficients is immediately changed.

When a color correction coefficient is selected in the mosaic monitor mode, the selected coefficient may be set in the latch 302 and output to the multiplier 301, for example.

Note that in the superimpose mode, the selector 312
It is possible to select the output of the second selection signal generation circuit 314 and make the color tone different between the superimposed area and other areas, but the explanation will be omitted.

(d) Registered image memory circuit The registered image memory circuit l registers in the memory 401 a registered image of the attention area of the document in the mosaic monitor mode,
This is a circuit that reads and prints a mosaic monitor image at any designated position on the paper.

FIG. 8 shows a circuit diagram of the registered image memory circuit l. Here, the memory 401 is a RAM in which registered images are registered. The selector 421 selects shading-corrected image data and "white" data. When reading and printing a mosaic monitor image, "white" data is selected.

The output signal of the selector 421 is sent to the 3-state buffer 4.
22 to the memory 401 and selector 446. The 3-state buffer 422 is in a high impedance state only when the memory 401 is being read (OE-“l”) when printing a mosaic monitor image.

In other cases, when a mosaic monitor image is not printed in mosaic monitor mode, "white" data is output. Well, when registering an image in mosaic monitor mode,
Output image data.

If the registered image is a full-color image, color adjustment is often required. Therefore, by using the selector 446 and the 3-state buffer 422, a memory is inserted before intermediate processing, and the multivalued data is stored in the memory. By reading this registered image data, a mosaic monitor image can be printed with various color adjustments.

The writing area determination circuit 402 determines whether or not the writing area is in the main scanning direction or the sub-scanning direction based on writing area setting signals in the main scanning direction (X) and the sub-scanning direction (Y) set by the CPU 25. Determine whether Based on the determination result, the AND gate 407 outputs the clock CKA if it is in the write area.
is output to the WE terminal of the memory 401 to enable writing to the memory 401.

Similarly, the readout area determination circuit 408 determines whether the readout area is in the main scanning direction or the subscanning direction based on readout area setting signals in the main scanning direction (X) and the subscanning direction (Y) set by the CPU 25. (The readout area is determined by the output format.) AND gate 405
Based on the determination result, if it is in the read area, a 0 is applied to the OE terminal of the memory 401 via the inverter 423.
'' and makes the memory 401 readable.

The write and read addresses for the memory 401 are:
They are generated by the write address generation counter 403 and the successive address generation counter 409, respectively, and are generated by the selector 40.
4 to the address terminal of the memory 401.

Selector 404 selects a write address or a read address depending on whether writing or reading is performed. Note that both the write address and read address are the address in the X direction and the address in the Y direction.
A one-dimensional address is generated based on the directional address using a multiplier and an adder.

Note that the selector 446 and the AND gate 448 are provided to output "white" data to the superimposed image portion when printing the original image in the superimpose mode, but a detailed explanation will be omitted. Selector 446 selects the output signal of 3-state buffer 422 or memory 401, except when a trimming signal is output in superimpose mode.

Below, the registered image memory circuit l will be explained in more detail.

When writing a registered image, when the user specifies an area of interest, the CPU 25 determines that this area is
Calculate how many lines (in the Y direction) the area is, and furthermore, how many pixels in the main scanning direction (X direction) the area is in. In other words, calculate the coordinates of the upper left corner of this area (x*, yo
) and the coordinates (x+, y+) of the lower right corner, and convert this coordinate to
The X portions 402a and 7 of the write area determination circuit 402 serve as write area setting signals for determining write areas in the direction and Y direction.
402b. X%Y refers to the main scanning direction and the sub-scanning direction, respectively. Writing area determination circuit 402
When the image leading edge signal is input, the X section 402a and the seventh section 402b count the horizontal synchronizing signal H5ync and the clock CKA, and compare whether the count value is within the write area setting range.

WEX if the main scanning direction is within the range (xe≦X≦x+)
-L' is output, and the sub-scanning direction is within the range (ya≦y≦y+
), outputs WEY-'L''. The write address generation counter 403 generates a write address when the write area determination circuit 402 determines that it is a write area, and outputs a write address via the selector 404. It is sent to the address terminal of the memory 401. That is, the X part 4 of the write address generation counter 403
At 03a, the clock CKA is counted when WEX-L', and an address related to the main scanning direction is generated. In addition,
This address is cleared by the horizontal synchronization signal H5ync.

Also, the Y section 403b of the write address generation counter 403
When WE Y -'L', counts the horizontal synchronizing signal H5ync and generates an address in the sub-scanning direction. Note that this address is cleared by the image leading edge signal generated by the CPU 25. The write address generation counter 403 includes a multiplier and an adder (not shown), and calculates a one-dimensional address from both the X-direction and Y-direction addresses.

When an address is generated in this manner and image data is written to the memory 401, the data holding signal is set to L' and the write/read signal is set to L''. Since a selection signal is sent through the write address generation counter 403, the address signal from the write address generation counter 403 is selected and transmitted to the address terminal of the memory 401.

Further, the clock CKA is transmitted to the WE terminal of the memory 401 via the inverter 406 and the AND gate 407.
Enables writing to memory. Also, the write/read signal is L.
', so the 3-state buffer 422
becomes active via the AND gate 405 only when it is possible to write the original image, and stores the image data in the memory 4.
Transmit it to the I10 terminal of 01. This allows the memory 401 to store only the image of the area that the write area determination circuit 402 determines is within the range in both the main and sub-scans. When writing is completed, the CPU 25 sets the data holding signal to 'H', inhibits writing via the AND gate 407, and holds the contents of the memory 401.

When reading data stored in the memory 401, it is necessary to read the data so that it is printed in a designated reading area. The circuit configuration required for reading is almost the same as that for writing. The CPU 25 operates on the
b is given a setting value that can be determined to be within the range when x0≦X≦x1 and y0≦y≦yl, taking into consideration the document reading magnification and printing magnification. Xo+5'o are the X and Y coordinates of the upper left corner P of the reading area, and! ++
Y+ are the X and Y coordinates of the lower right corner P1 (see FIG. 6).

When the image leading edge signal is input during scanning, the readout area determination circuit 408 counts the horizontal synchronizing signal H5ync and the clock CKA, and compares whether the count value is within the successive area setting range. If the main scanning direction is within the range, REX-'L' is output, and if the sub-scanning direction is within the range, REY-'L' is output.

The successive address generation counter 409 generates a read address when the read area determination circuit 408 determines that the area is a read area, and this address is sent to the memory via the selector 404 since the write/read signal is 'H' at the time of reading. 401 address terminal. That is, the X unit 409a of the successive address generation counter 409 counts the clock CKA when REX-L', and generates an address in the main scanning direction. Note that this address is the horizontal synchronization signal H.
Cleared with 5 sync. Further, the seventh section 409b of the successive address generation counter 409 counts the sub-scanning clock from the sub-scanning clock generator 29 for variable magnification of REY-'L'', and generates an address in the sub-scanning direction.Horizontal synchronization signal The reason why the sub-scanning clock is counted instead of H5ync is to take magnification into consideration. Note that this address is cleared by the image leading edge signal generated by the CPU 25.

In the read address generation counter 409, a one-dimensional address is generated from the addresses in the main scanning direction and the sub-scanning direction using a multiplier and an adder (not shown).

Data read out by accessing the memory 401 is transmitted to the subsequent stage. At this time, of course, a request is made to count the read address counter 409 in the read area even if it exceeds the maximum size of the memory, but in this case, the X section 409a and the 7 section 409b of the read address counter overflow every time they overflow. While outputting signals X and Y, counting starts again from the initial value. The overflow signals X and Y are output to an image tone setting circuit 2 arranged at a subsequent stage. The overflow signals X and Y are used when a plurality of images are arranged horizontally and printed in different tones in a mosaic monitor mode.

Note that during reading, since the write/read signal is 'H', the read area (REX-'L').

REY-'L''), the memory 401 is in an output enabled state via the AND gate 405 and the inverter 423, and the 3-state buffer 422 is in a high impedance state via the AND gate 405, and the image data input side is is separated from the memory 401.

Further, when the memory 401 is readable (OE = 'L'), the selector 446 selects the read data of the memory 401 by the selection signal via the AND gate 448, and in other cases, the data is read from the memory 401 as shown in FIG. Since it is necessary to read data so that it can be printed such as a format, "white" data is selected to make the image data "white" except when reading data from memory.At this time, the read area discrimination circuit Coordinates 408a and 408b are set in consideration of the difference between the original reading magnification and the printing magnification of the contents of the memory 401.The sub-scanning clock for variable magnification used for printing is set at the same magnification as the original reading magnification at the same magnification. Make them match.

Taking Figure 6 as an example, if you want to output a 3x9 image, the way to read the memory is to read the contents of the same line three times in the main scanning direction, read out all the contents in the sub-scanning direction, and then read out the contents in the main scanning direction again. It will be read from the beginning.

When the output of the X section 408a and the 7 section 408b of the reading area determination circuit that determines the reading area for the paper is possible (OE
-'L''), X section 409 of read address generation counter
A, 7 unit 409b generates an address, uses the address to access memory 401, and transmits the stored image data to the subsequent stage via selector 446. Here, the CPU 25 determines that x0≦X≦X in the X section 408a of the read area determination circuit.

In this case, the seventh section 408b is given a setting value that allows it to be determined that it is within the readout range when y, ≦y≦y1. At this time, when the successive address generation counter 409 exceeds the maximum size of l block (-(X□-xo)/3), it outputs an overflow signal X and starts counting again from the initial value.

Then, read out the contents of the same line. Repeat this three times. When it advances by (y, -y,)/9 in the sub-scanning direction, the succession of three blocks in the horizontal direction is completed, and over 70 -
Signal Y is output. In this way, three images are printed in the horizontal direction. By repeating this nine times in the sub-scanning direction, a mosaic monitor image of 3×9 blocks is read out.

Note that in the image tone setting circuit 2, different color correction coefficients are set for each block corresponding to the over 70-signals X and Y (FIG. 13(a)).

(see (b)), each image will be printed with different color adjustments applied.

(e) Flow of copying machine control related to mosaic monitor mode FIG. 9 shows the CPU 25 controlling the digital color copying machine.
7 shows a main 70- related to the superimpose function and mosaic monitor mode of copy operation control. Operation panel 70
When the function key 78 or 79 is pressed to enter the superimpose mode or the mosaic monitor mode, the main 70- is entered. Normally, selecting the mosaic monitor mode means "YES" to both the image registration request (step Sl, hereinafter "step" will be omitted) and the mosaic monitor output request (S3).

Furthermore, selecting the superimpose mode means "YES" for both the image registration request (Sl) and the superimpose mode output request (S5).

If there is a request for image registration (YES in Sl), image registration processing is performed (S2, see Figure 1O). Image registration means to register the contents of an image in a designated area. In the image registration process (S2), the user sets a desired area and registers the contents of the area in the memory. Area setting involves reading the original image, displaying the read image on the display section 84,
The desired area is set using the jog dials 82 and 83 and the set key 76.

If there is a mosaic monitor output request (YES in S3), mosaic monitor output processing (S4, see FIG. 11) is performed.

That is, the registered content is read out, various color corrections are performed on it, and a mosaic monitor image is output. At this time, reset the printing conditions such as the number of prints and magnification to the initial values (all reset), and set the density adjustment level to the standard value. When the user selects an image with a desired color balance from among the output mosaic monitor images and issues a copy request, the copy operation is performed and the entire image is obtained with that color balance.

In the case of superimpose output request (YES in S5),
Superimpose output settings are performed (S6).

That is, after checking whether there is a registered image, settings for reading from the memory are made. Next, when a copy request is made (YES in S7), the copy is performed (S8, S9),
The registered image is printed over the original image.

If there is no image registration request, mosaic monitor output request, or superimpose output request (Sl, S3.S5
(No in both cases), perform normal copying (S7 to S9)
.

Note that area settings in the mosaic monitor mode and superimpose mode are performed using the display section 84 as described in section (b).

FIG. 10 shows the flow of image registration processing (S2). When the set key 76 is pressed on the operation panel 70, the area setting value set on the display section 84 at that time is input (S21). Furthermore, various other input values are set (322).

Next, it is determined whether or not to start image registration (S31
). When starting image registration, select the vertices (upper left corner and lower right corner) of the registered image area from the input area setting value (521).
calculates the coordinates of , outputs a writing area setting signal to read the document image in that area (S32), corrects the shading of the basic signal (S33), and stores the correction value in memory 4.
01 (S34). Then, the image registration request is cleared (S35) and the process returns. If image registration is not to be started (No in 531), the image registration request is immediately fulfilled (S35) and the process returns.

FIG. 11 shows the flow of mosaic monitor output processing (S4), which is a feature of this embodiment. First, the conditions for reading out the contents of the memory 401 of the region of interest are set (551), and the color correction coefficients y, , m-, c, (i-0+2 )ll is calculated (S52). That is, in this embodiment, the color correction coefficient is set in three stages by increasing or decreasing the color correction adjustment value a with respect to the standard value.

Yo ← Yr a 'It''Vl+ a IIIo ← m, -a m, ←Ill + a CO← C, -a C2←C, + a Then, read out the memory contents, set the color correction coefficient, and create a mosaic monitor image. is printed (S53).

Note that the standard value Y l + m l + CI is set to an initial value when the power is turned on, but a value selected from the mosaic monitor image may be used (S92). Also,
The initial value may also be changed (Sill).

Next, when the user selects a desired image (block) from among the mosaic monitor images on the display unit 84 (S61)
, set color correction coefficients according to the selected image. First, it is determined whether the color correction coefficient selected for yellow is y (S62), and if y, the value of y is set to y (S63). If not y, then it is determined whether the selected color correction coefficient is yl (S
64).

If it is yI, proceed directly to S71; if it is not ir,
The value of y is set to yl (S65). That is, here, yl represents the selected yellow color correction coefficient.

Next, t is selected for magenta; the color correction coefficient is mo
It is determined whether or not (S71), and if m, then m
Let the value of o be m (S72). If it is not mo, then it is determined whether the selected color correction coefficient is m (S73). If it is ml, proceed directly to S81, and m
, otherwise, the value of ml is set to m (S74). That is, here, ml represents the selected magenta color correction coefficient.

Next, it is determined whether or not the color correction coefficient selected for cyan is 00 (S81). If it is co, the value of co is set as CI (S82); if not c, next: It is determined whether the selected color correction coefficient is c (
S83). If it is C3, proceed directly to 591; if it is not CI, set the value of C8 to 01 (S84). That is, here, C'l represents the selected cyan color correction coefficient.

Next, it is determined whether or not to set the selected color correction coefficient to a standard value (591). At this time, the display section 84 of the operation panel 70 displays the message "Do you want to set the selected color balance as the standard value?" as shown in FIG. ” is displayed, and the user sets YES or No using the jog dials 82 and 83 and the set key 76. When performing settings, store the selected value set in steps 362 to S84 above as the standard value (5
92).

Next, it is determined whether to start the mosaic monitor mode (S93). For example, if the user wants to print a mosaic monitor image based on the standard values newly set in S92, the user presses the function key (mosaic monitor selection key) 78 to start printing. When start is selected, the process returns to S51 and mosaic monitor output is performed. If start is not selected, the process advances to 5101.

When the print start key 71 is pressed to request copying (S101), scanning of the original is started, and copying is started using the set color correction coefficient selection value Y l + m l * Ct ( S l 02). Then, copying is performed until the copying is completed (S103).

When copying is completed, the selected value Vr + mr + Ct of the color correction coefficient used for copying is stored as a standard value (S l l l), and the process returns. This standard value becomes the initial value of the color correction coefficient in the next mosaic monitor mode.

Note that the user may be allowed to select whether or not to set the standard value as the initial value.

FIGS. 13(a) and 13(b) show a 70 step process for setting coefficients for color adjustment in printing a mosaic monitor image.
-It is a chart.

This process is executed as an interrupt routine by interrupting the CPU 25 every time the horizontal synchronizing signal H5ync is generated.

Among these, the counter Ctl is the leading edge of the print paper P (
The distance from the leading edge of the image in the sub-scanning direction is counted, and the beginning of printing and the end of the printing path of the mosaic monitor image GM are detected. The counter Ct2 counts the distance in the sub-scanning direction and detects changes in blocks of the mosaic monitor image. T
represents the distance in the sub-scanning direction from the leading edge of the image to the printing position of the mosaic monitor image, and α represents the distance of the l block in the sub-scanning direction (see FIG. 6).

First, the state is determined at 5300, and its value is "0" ~
Branch according to "4".

When the state is "0", it is determined whether or not it is the leading edge of the image (leading edge of the paper P) (5301), and when the leading edge of the image has passed, the counter Ct is initialized (S30).
2) Set the state to "1" (S303).

When the state is rlJ, wait until the counter Ct8 becomes T (3311), that is, wait until the position of the coordinate y0 which is the tip of the mosaic monitor image GM is reached, and then, depending on the color of the toner of the developing device used, Jump to state r2 J, r3 J, or r4 J.

In other words, when Y (yellow) (YES at 5312)
sets the state to "2" (S313). When M (magenta) (YES in S321), initialize the counter C5 5322), set the variable i to "0" 5323),
The state is set to "3" (S324). When it is C (cyan) (No in S321), the counter Ct2 is initialized 5331), the variable j is set to "0" 5332), and the state is set to "4" (S333).

When the state is r2J (Y scan), a latch signal is output to the image adjustment circuit 2 and latches 302, 303, .
Yo+Yt as coefficients 1 to 3 set in 304 respectively
+Yt is latched (5341), counter C1 is (
Wait until T+91, that is, wait until the position of coordinate y1, which is the rear end of mosaic monitor image GM, is reached (
S 342), set the state to “0” (S 343)
.

When the state is r3J (M scan), latch 30
Substitute m for coefficients 2 to 304" to 3 (S351)
, counter Ct becomes Q, that is, waits until l blocks of the mosaic monitor are completed (S352
), initialize counter c5 s 353), variable i
is incremented by one (S354). Next, wait until the rear end of the mosaic monitor image is reached (S355).
, the state is set to "0" (S356). That is, here, coefficients 1 to 3 are set to the same value m, and each time the mosaic monitor image changes l blocks in the sub-scanning direction, coefficients 1 to 3 are changed to a new value m i+ 1. .

When the state is r4J (C scan), latch 3
Substitute C1 for coefficients 1 to 3 of 02 to 304 (S361)
, counter Ct, becomes (3Q), that is, waits for the completion of 3 blocks of the mosaic monitor (S
362), the counter Ct is initialized 5363), and the variable j is incremented by one (S364).

Next, wait until the rear end of the mosaic monitor image is reached (S
365), and the state is set to "0" (S366).

That is, here (j, the coefficients l~ of latches 302-304
3 are set to the same value C1, and each time the mosaic monitor image changes by three blocks in the sub-scanning direction, coefficients 1 to 3 are changed to a new value cj+1.

When the processing in each state is completed, the counter Ct.

Increment C5 (S371).

Through the above processing, various coefficients are set for each block for each print color, and color adjustment is performed.

Margins Below (Effects of the Invention) Conventionally, if an image with the color balance desired by the user is not found among the mosaic-monitored images, the user has to operate the mosaic monitor again, making the operation complicated.

According to the present invention, when it is desired to print a mosaic monitor image again outside the range of the mosaic monitor image, the mosaic monitor image can be obtained again without scanning the document reading centering on the image closest to the desired image. Therefore, a satisfactory color balance can be easily selected.

Additionally, changes in color balance over time can be adjusted at the user level.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of a digital color copying machine. FIG. 2 is a block diagram of the signal processing section. FIG. 3 is a timing chart of image data processing. FIG. 4 is a plan view of the operation panel. FIG. 5 is a diagram of attention area setting. FIG. 6 is a diagram of an output format of a mosaic monitor image. FIG. 7 is a circuit diagram of the image tone setting circuit. FIG. 8 is a circuit diagram of the registered image memory circuit. FIG. 9 is a diagram of the main 70- in the mosaic monitor mode of the digital color copying machine. FIG. 1O is a 70-chart of the image registration process. FIG. 11 is a flowchart of mosaic monitor output settings. FIG. 12 is a diagram of a screen for setting selected values to standard values. FIGS. 13(a) and 13(b) are flowcharts of interrupt processing. ■...Registered image memory circuit, 2...Picture setting circuit,
20...Signal processing unit, 25...CPU. 70...Operation panel, 78...Mosaic monitor selection key 84...Display section, 401...Memory. Figure 9 Figure 10 Figure 11 Hand-glazed 2 Moss 1j Orthographic (method) % formula % 2. Name of the invention Digital color copying machine 3. Person making the amendment Relationship to the case

Claims (1)

[Claims] (1) Multiple images are printed at different positions on the same paper by performing different color correction calculations on the image data of a certain area in the original image, and the user selects the desired image from among these multiple images. A digital color copying machine equipped with a mosaic monitor mode that performs color correction calculations includes a color correction coefficient calculation means that performs predetermined calculations on standard values to obtain multi-level color correction coefficients used in color correction calculations; The present invention includes a standard value setting means for setting the color correction coefficient to a standard value for the next color correction calculation, and an instruction means for instructing printing of the plurality of images again after the standard value setting means sets the standard value. A distinctive digital color copying machine.