JPH0223376A - Digital color copying machine - Google Patents

Abstract

PURPOSE:To develop no error in selecting color adjustment by providing a density setting means automatically setting a printing density level at a reference value when printing is carried out in a mosaic monitor mode. CONSTITUTION:In the initialized mosaic monitor mode, the density setting means 80 automatically sets a density level at the reference value. Consequently, plural images are printed at the reference density level in the mosaic monitor mode, in which the density setting means 80 is not needed. Therefore, the density level set by the density setting means 80 is previously accorded with a color adjustment coefficient, and the density setting means 80 itself adjusts a color adjustment coefficient. Since density is set at the reference value in the mosaic monitor mode all the time, color adjustment is not mistakenly selected.

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 blocks a color image sensor to read a document and converts it into a print output signal, and a printer section that prints an image on paper using electrophotography in response to this print output 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 is generally equipped with a masking circuit, and outputs -
Generates a color-corrected signal according to the characteristics of the device (printer, etc.).

Although a color-corrected image is printed in this manner, 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, the color was determined by making a copy for each color adjustment and then cutting and trying. 14N adjustment was performed, and scanning was repeated for the number of adjustments times the number of printed colors, which was wasteful in terms of time and cost.

Therefore, in another application, the present applicant proposed a color adjustment selection method (hereinafter referred to as a mosaic monitor) for reducing 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 the image data of the attention area is stored in the image memory means.

Next, color correction is performed on the image data read from the image memory means at various different predetermined color correction levels, and these are copied at different positions on the same sheet of paper in one printing process. The user selects the image closest to the color of the original image or the user's favorite color from among the images of multiple areas of interest in different tones (mosaic monitor images) copied onto a single sheet of paper. do. 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.

By the way, when copying, the density level may be adjusted to an appropriate value depending on the original image.

Therefore, when entering the mosaic monitor mode, the density level may differ from the standard value.

At this time, the mosaic monitor image is also printed at that density level.

When a user looks at a mosaic monitor image and selects a desired color adjustment, if the density level is not a standard value, there is a risk of making a wrong selection.

SUMMARY OF THE INVENTION An object of the present invention is to provide a digital color copying machine that is less prone to errors in color adjustment selection in mosaic monitor mode.

(Means for Solving the Problems) A first digital color copying machine according to the present invention performs different color correction calculations on image data of a specific area in a document image to print a plurality of images on the same sheet of paper. A digital color copying machine equipped with a mosaic monitor mode for printing is characterized in that it includes density setting means for automatically setting the density level of printing to a standard value when printing in the mosaic monitor mode.

The second digital color copying machine according to the present invention further includes:
Equipped with a concentration setting means that allows the user to set the concentration level,
When the density level is set by the density setting means in the mosaic monitor mode, the printing control means is characterized in that it sets a color correction coefficient corresponding to the density level in advance.

(Function) The density setting means automatically sets the density level to a standard value in the initial setting of the mosaic monitor mode.

Therefore, multiple images in mosaic monitor mode are printed at standard density levels.

Therefore, in the mosaic monitor mode, the density setting means is not required, so that the density level set by the density setting means is made to correspond to the color adjustment coefficient in advance, and the color adjustment coefficient can be adjusted by the density setting means.

Margin below (Example) Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

(a) Structure of Digital Color Copying Machine The digital color copying machine according to the present invention includes a reading unit that reads a document using an image sensor and converts it into a print output signal, and an electrophotographic method that prints paper on paper in response to this print output 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 10 includes an exposure lamp 12 that irradiates the original, a rod lens array 13 that collects reflected light from the original, and
It is equipped with a contact type COD color sensor (image sensor) 14 that converts the collected light into an electrical signal. When reading a document, the scanner 10 is driven by a motor 11 to move in the direction of the arrow and scan the document placed on the platen 15. The image of the document surface illuminated by the light source 12 is C.
Photoelectric conversion is performed by the OD color sensor 14.

R and G obtained by the COD color sensor 14.

The electric signal (multi-value) of B is processed by the read signal processing section 20,
It is converted into a print output signal (binary) of yellow, magenta, cyan, or black, and stored in the buffer memory 30. In the print head unit 31, an LD drive circuit 32 causes a semiconductor laser (LD) 33 to blink according to the print signal from the buffer memory 30 (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.
The light is irradiated by a sub-eraser lamp 44, charged by a charger 43, and further irradiated by a sub-eraser lamp 44. When exposed in this state, an electrostatic latent 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 lO is synchronized with the operation of the photoreceptor drum 41 and the transfer drum 51.
repeats the scanning operation.

Thereafter, the paper is separated from the transfer drum 41 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, with reference to FIG. 2, a description will be given of the signal processing section 20 that processes the output signal of the COD color sensor 14 and outputs a binary image signal.

When outputting a normal image, the image signal photoelectrically converted by the COD color sensor 14 is converted into an image density by the log amplifier 21, and then the dental value (
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, G, and B 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. The control signal from the CPtJ 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. L.D.
The 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.

Note that the clock generators 2 and 8 generate a horizontal synchronizing signal Hsync 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 key tone sub-scanning clock is generated, which may be an interrupt signal to the registered image memory circuit 1.

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, C from the COD color sensor 14;
, B should be transferred unrealistically in synchronization with CKA (in the figure, the number of image data indicates the address in the main scanning direction).

Every time the horizontal synchronization signal Hsync is generated, line n in the main scanning direction is updated. In other words, the scanner lO has advanced by a unit distance in the sub-scanning direction.

This digital color copying machine is called a mosaic monitor and is equipped with color adjustment and superimposition functions.

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 7N for starting the copying operation and an interrupt key 7 for specifying interrupt copying.
2. Clear/stop key 73, all reset key 7
4. Numeric keypad 75, set key 76, cancel key 7
7. Provided with various function keys 78 to 81, job dials 82 and 83 for setting areas to 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. It is being Here, function key 78°79.80
are a mosaic monitor selection key, a superimpose mode selection key, and an a degree 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 in the document area ED on the display section 84 of the operation panel 70 and performing a preliminary scan using the scanner IO,
The original image is roughly displayed. Vertical and horizontal direction lines LPY
, LPX is the center of area EA. When the job dials 82 and 83 are operated, these indication lines move left and right or up and down, respectively, thereby defining the area EA, and by pressing the set key 76, the area of interest is set.

The density correction key 80 is a key for adjusting the copy alt by setting/changing the density adjustment coefficient.

The density adjustment coefficient can be adjusted in nine stages, for example, as shown in FIG. Level 5 is the standard value, levels 6 and above are greater than the standard value, and levels 4 and below are smaller than the standard value. The density adjustment level is incremented by the number of times the a-variation correction key 80 is pressed, and the number (one character from 1 to 9) of the selected level is displayed as an inverted character on the display section 84. A signal corresponding to the selected level is sent from the operation panel 70 to the CPU 25, and the CPU 25 sets a density correction coefficient according to the signal, and adjusts the density by changing the amount of toner adhering by changing the amount of charge, etc. Note that, as will be explained later, in the mosaic monitor mode, the density correction coefficient is automatically set to a standard value, so it is not used. Therefore, the density correction key 80 is
In mosaic monitor mode, it acts as a color correction key.

(b) Mosaic monitor and color correction adjustment function The mosaic monitor has a registered image memory circuit ((d
This is realized by an image setting circuit (see section (C)) 2 that performs color adjustment in the printing process (see section (C)).

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 vapor. 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 looks at the pre-scanned document image displayed on the display section 84 of the operation panel 70 and selects the area of interest (for example, the shaded area in FIG. 5) where the user wants to make the most color adjustment. Set. Correspondingly, in the next scan, the registered image memory circuit stores only the image data (2) corresponding to the setting value of the region of interest 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 prints images of various tones on the same sheet of paper from the image data l read out from the registered image memory circuit 1 and turned into print color data by the masking processing circuit 24. k=Ky, Kn, Kc). Here, Ky, Kn.

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=m=, Kc=c, (i= 0, 1.

2) to output 3x3x3=27 types of images.

The color correction coefficient ct * m + + with "bi" added here
"V" represents the standard coefficient of color adjustment, "O", color correction coefficient with "2"Co+ll1o+Yo; et, f
fl*+Vt is the standard coefficient CI + 11, respectively
11*V Indicates a coefficient obtained by multiplying I by a predetermined factor smaller than 1 and a predetermined factor larger than 1.

The user selects the optimum color tone from the 27 types of output images shown in FIG. This ends the 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 user may operate the function keys 78 to 81 to read 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.

The document is then read again and the image is printed in the set color tone.

The needs of users who use mosaic monitors vary.
There are cases where you want to change the color adjustment greatly or strictly. To meet these needs, a mosaic monitor has a color correction adjustment function.

The color correction coefficients Ky, Kll+, and Kc can be changed in two ways: before performing mosaic monitoring and after viewing the printed mosaic monitor image.

In this example, the color correction coefficients c, , mi, yl (i=0
', 2').

is the standard color correction coefficient C10m1. It is obtained by subtracting and adding a predetermined color correction adjustment value a to yl. Therefore, adjustment before mosaic monitoring is performed by changing the color correction adjustment value a. The color correction adjustment value a can be set using the number keys 75 on the operation panel 70. With this setting, the color correction coefficient is changed as follows.

Yo"Y+ a yl ° Y++a ffio ← ff1l -a my ← L + a CO← C1-a C1← C1+ a If you want to change the color adjustment greatly, increase the value of a. If you want to change it small, increase the value of a. Just set it small.

Color correction coefficients KVKm, K after viewing the mosaic monitor image
The adjustment of c is also performed by changing the color correction adjustment value a. In this case, the color correction adjustment value a can be changed using the operation panel 70.
This is done using the density correction key 80.

When performing mosaic monitoring, the density adjustment coefficient should be set to the standard value since it is usually printed at the same density as the original (No. 13).
Figure, 552). Therefore, there is no need to perform density correction using the density correction key 80. Therefore, in the mosaic monitor mode, the density correction key 80 is used as a color correction key for color correction.

For this reason, as shown in FIG. 7, a selector 35 for switching between density correction and color correction is provided, and when a mosaic monitor select signal is received from the CPU 25 at the time of mosaic monitor output, the signal from the density correction key is output as a color correction adjustment value signal to the CPU.
I will send it to U25. That is, when the density correction key 80 is pressed on the operation panel 70, the level is incremented by one step and displayed as reverse characters on the display section 84. This level corresponds to nine levels of color correction adjustment values a as shown in FIG. Therefore, when the set key 76 is pressed, the CPU 25 changes the color correction coefficients y, , m, from the color correction adjustment value a corresponding to that level.

Set c, (i=o, 2). In this way, the density correction key 80 is used as a color correction key.

When the level is 5, it is a standard color. If you want to increase the color change in one step of the mosaic monitor image, you can change the color correction adjustment value a by selecting one of 6 to 9, and if you want to change it to a smaller value, select one of 1 to 4.

At this time, as in the case of the adjustment before performing the mosaic monitor, yo ← Y+ a ytsu; ←Y-+a ++1o ←L a seagull! ← Ill + a Co ← C, -a C! ← C, + a After performing color correction in this manner, the memory contents are read out again and the mosaic monitor image is printed. Then, a desired color adjustment is selected from this mosaic monitor image.

In this example, three colors C are used. Both M and Y are changed in 3 steps to print a mosaic monitor image, but if the user wants to make even more precise color adjustments, they can be changed in even more steps (for example, 5 steps) and printed. . Although a detailed explanation will be omitted, the number of stages can be changed by controlling the continuous area setting signal given to the registered image memory circuit 1 by the CPU 25 and the color correction coefficient given to the image tone setting circuit 2.

Margin below (c) Picture setting circuit FIG. 9 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 image signals of three colors R, G, and B into prints corresponding to each print color of Y (yellow), M (magenta), C (cyan), and K (black). It is converted into an image signal (print signal), and the converted image signal is output 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 att 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.

The color J, 1 setting in the image adjustment circuit 2 is determined by Y,= for each print signal Y, M, C obtained by the above calculation
KyXY M+ = KIXM C+ = K c X C is calculated, and the adjusted print signals Y + , M +
, to obtain CI. Here, Ky, Km, K
c 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 continuous area specified by P o (xo, yo) and P + (L, l'+) is divided into blocks of 3 columns in the main scanning direction X and 9 rows in the sub scanning direction Y, and each division A different combination is set for each. In that case, the coefficient KV of Y (yellow) does not change in the sub-scanning direction Y, and the coefficient KV of Y (yellow) does not change in the main scanning direction
Yes. + Y + + '/t, and the coefficient Km of M (magenta) changes in the main scanning direction X, and m for every block in the sub-scanning direction Y. * m++ mu.

Changes sequentially as 1@O+ ffl+..., C (cyan)
The coefficient Kc does not change in the main scanning direction, but changes to C6+CI+Ct every three blocks in the sub-scanning direction.

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 tone setting circuit 2, a multiplier 301 executes calculations to obtain the above-described print signals Y + , M + , and CI. Here, in order to set three coefficients in the main scanning direction in the mosaic monitor mode, a latch circuit 305 consisting of three latches 302, 303, and 304 is provided.
The coefficients output from the PU 25 are set. These three coefficients are values corresponding to three blocks in the main scanning direction, respectively. Every time the sub-scanning clock for scaling is input to the CPU 25 as an interrupt signal, the interrupt processing (
(See FIGS. 14(a) and 14(b)) is performed, and each time the image advances by one block in the sub-scanning direction, the CPU 25 outputs a latch signal to the image setting circuit 2, and sets a new 3-bit loss for the next block. The latches 302, 303, and 304 are latched.

Latch circuit 305 consisting of three latches 302 to 304
is provided because the coefficient change period is short in the main scanning direction, and it is difficult to set it in real time using the CPL 125 in terms of speed. Note that if it is desired to set the color correction coefficients to nN classes, n latches may be provided in parallel.

In the registered image memory circuit 1 described above, the image memory 401
The overflow signal X in the main scanning direction generated when reading is inputted to the first selection signal generation circuit 31, and
The selection signal generation circuit 311 outputs a signal for sequentially selectively switching the selector 306 or each of the latches 302 to 304 each time the overflow signal X is input (for each block). In the mosaic monitor mode, the selector 312 transmits the output of the first selection signal generation circuit 311 as 821 to the selector 306.

The selector 30B 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
The overflow signal Y in the sub-scanning direction generated when reading is manually input to the selector 313;
13 transmits this 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, for example, the latch 302 and multiplied by 1301+.

Note that in 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 area of interest of the document in the mosaic monitor mode,
This is a circuit that reads and prints at any designated position on paper for copying.

FIG. 10 shows a circuit diagram of the registered image memory circuit 1. Here, the memory 401 is a RAM that records registered images. 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 42
2 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, the mosaic monitor is in the mosaic monitor mode. When no image is being printed, white data is output. Also, when registering an image in mosaic monitor mode, image data is output.

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 continuous area determination circuit 408 determines whether the continuous area is in the continuous area in the main scanning direction or the sub-scanning direction based on continuous area setting signals in the main scanning direction (X) and the sub-scanning direction (Y) set by the CPU 25. (The successive area is determined by the output format.) AND gate 405
Based on the determination result, if it is in the successive region, it is connected to the WE terminal of the memory 401 via the inverter 423.
0'' is output, and the memory 401 can be continuously output.

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.

The selector 404 selects a write address or a continuation address depending on whether it is a write or a continuation. Note that both the write address and the subsequent address are the address in the X direction and the address in the Y direction.
A one-dimensional address is generated using a multiplier based on the directional address.

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 description thereof 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) and how many pixels in the main scanning direction (X direction) the area is, that is, calculate the coordinates of the upper left corner of this area (xo,
yo) and the coordinates (x+, y+) of the lower right corner, and use these coordinates as a writing area setting signal for determining the writing area in the X direction and the Y direction.
and 7 section 402b, respectively. xSY refers to the main scanning direction and the sub-scanning direction, respectively. Writing area discrimination circuit 4
When the image leading edge signal is input, the 02 X section 402a and the 7 section 402b output the horizontal synchronization signal Hsync and the clock CKA.
is counted and compared to see if the count value is within the write area setting range.

If the main scanning direction is within the range (XO≦X≦Xυ, then WEX=
°L' is output, and the sub-scanning direction is within the range (yo≦y≦y+
), outputs WEY='L'. A write address generation counter 403 generates a write address when the write area determination circuit 402 determines that the area is a write area, and sends it to the address terminal of the memory 401 via a selector 404. That is, the X section 4 of the write address generation counter 403
In step 03a, when WEX=L°, the clock CKA is counted and an address related to the main scanning direction is generated. Note that this address is cleared by the horizontal synchronization signal Hsync.

Also, the seventh section 403b of the write address generation counter 403
counts the horizontal synchronizing signal Hsync when WEY='L' 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 is equipped with a multiplier, and generates an address in this way to calculate a one-dimensional address from both the X-direction and X-direction addresses. is set to °L°, and the ti its/read signal is set to "Lo."Thereby, the selector 404 selects AND
A selection signal is sent through the gate 405, and the address signal from the write address generation counter 403 is selected.
It is 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, 1 prisoner/read signal is “
Since it is set to Lo, the 3-state buffer 42
2 is an AND game only when it is possible to write the original image,
-) becomes active via 405 and transmits image data to terminal 110 of memory 401;

In addition, the upstream write area determination circuit 402 can store in the memory 401 only images of areas determined to be within the range in both main and sub-scans. When the writing is completed, the CPU 25 sets the data holding signal to "H" and
Writing is prohibited through gate 407 and memory 401
Retains the contents of.

When reading data stored in the memory 401, it is necessary to read the data so as to print it in a designated continuous area. The circuit configuration required for continuous printing is almost the same as that for writing. The CPU 25 operates an
b is given a set value that can be determined to be within the range when XQ≦X≦X4 and Ya≦y≦Y. xO+Yo are the X and X coordinates of the upper left corner of the readout image area, and x1y are the X and X coordinates of the lower right corner (
(See Figure 6).

When the image leading edge signal is input during scanning, the continuous area determination circuit 408 counts the horizontal synchronizing signal H5ync and the clock CKA, and compares whether the count value is within the readout 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 successive address when the read area determination circuit 408 determines that it is a successive area, and this address is sent to the memory via the selector 404 since it is a write/read signal at °H° when the readout area is determined to be a successive area. 401 address terminal. That is, the X section 409a of the successive address generation counter 409 counts CKA when RBX-'L', and generates an address regardless of the main scanning direction. Note that this address is cleared by the horizontal synchronization signal 1 (sync). Also, the 7th part 409b of the read address generation count 409 receives the sub-scanning clock from the sub-scanning clock generator 29 for scaling when REY='L'. Counts and generates an address related to the sub-scanning direction.The reason why the sub-scanning clock is counted instead of horizontal synchronization signal 1 (sync) is to take magnification into consideration.This address is based on the image leading edge signal generated by CPtJ25. Cleared by

A one-dimensional address is generated from the addresses in the main scanning direction and the sub-scanning direction.

The data read out by accessing the memory 401 is transmitted to the subsequent stage. At this time, of course, within the continuous area, the continuous address counter 409 is requested to count even if it exceeds the maximum memory size, but in this case, the X part 409a and the Y part 409b of the continuous 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 continuous output, the write/read signal is °l]°, so the continuous output area (REX="Lo.

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

Further, when the memory 401 can be read out continuously (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 format shown in FIG. Since it is necessary to read out data so that data can be printed as shown in FIG. , 408b are set with coordinates that take into consideration the difference between the original reading magnification and the printing magnification of the contents of the memory 401. Note that the sub-scanning clock for magnification is made to match the original reading magnification.

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

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

When this is the case, the seventh section 408b is given a setting value that allows it to be determined that when Yo≦y≦y1, it is within the successive range. At this time, when the successive address generation counter 409 exceeds the maximum size (=(X, -Xo)/3) of 1 block OJ, 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 the image advances by (y+yo)/9 in the sub-scanning direction, the succession of three blocks in the horizontal direction is completed, and an overflow 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 setting circuit 2, an overflow color correction coefficient is set (see FIGS. 14(a) and 14(b)).
, each image will be printed with different color adjustments.

The following differs for each block according to the margin low signals X and Y (e)
FIG. 11 shows the flow of copying machine control related to the mosaic monitor mode.
5 shows the main flora related to the superimpose function and mosaic monitor mode of the copy operation control in No. 5. Operation panel 7
0, when the funk key 78 or 79 is pressed to enter the superimpose mode or mosaic monitor mode, this main flow is entered.

If there is a request for image registration (YES in step St, hereinafter "step" will be omitted), image registration processing is performed (Sl
, see Figure 12). Image registration means to register the contents of an image in a designated area. Selecting the normal mosaic monitor mode means image registration request (St),
Both the mosaic monitor output request (S3) are ``YES''. Also, selecting the superimpose mode means that both the image registration request (St) and the superimpose mode output request (S5) are ``YES''. In the image registration process (Sl), the user sets the desired area and registers the contents of the area in the memory.The area setting is performed by reading the original image, displaying the read image on the display section 84, and setting the desired area. The 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. 13) 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 copying conditions such as the number of prints and magnification to the initial state (All Reset), and set the density adjustment level to the standard value. When the user selects an image with the desired color balance from among the output mosaic monitor images and issues a copy request (YES at S7), the copy operation is started (S8).
), and when copying is performed until the end of copying (S9), 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 are made to continue reading from the memory. 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 (87-S9)
.

Note that area settings in the mosaic monitor and superimpose mode are performed using the display unit 84.

FIG. 12 shows the flow of image registration processing (Sl). 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 input values for the pond are set (S22).

Next, it is determined whether +a, Kc is changed to the color correction coefficient Ky (S23). When there is an input using the numeric key 75, it is determined that the color correction coefficient is changed. When a numerical value is input using the number key 75, that value is set as the color correction adjustment value a (S24).

Then, the color correction coefficient is changed using the coefficient #la (S25). That is, yO''l'+ a Yt←Y+ 10a fflo ← L a m!←m+ + a CO← C+ -8 C1←at + a 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 values (S21).
The coordinates of the area are calculated and the document image of that area is read (S
32), the basic signal is subjected to shading correction (S
33), the correction value is written into the memory 401 (S34).

Then, the image registration request is cleared (S35) and the process returns. If you do not want to start image registration (No in S31),
Immediately clear the image registration request (S35) and return.

FIG. 13 shows the flow of mosaic monitor output processing (S4). First, reset all setting values used for the mosaic monitor (551) and set the density adjustment coefficient to the standard value (551).
S52). That is, if the density adjustment coefficient has been changed before performing mosaic monitoring, it is automatically returned to the original standard value. By always returning to the standard value in the mosaic monitor mode, errors in color adjustment selection in the mosaic monitor mode are less likely to occur.

Next, read out the contents of the memory 401 of the region of interest 553
), color correction coefficients y, te, , c= are output to the image tone setting circuit 2 to perform color correction (S54), and print a mosaic monitor image (S55).

Next, it is determined whether the color correction coefficients y, , m, , c are to be changed (961). When the density correction key 80 is pressed on the operation panel 70, the color correction coefficient is changed. When the set key 76 is pressed, the density correction key 80
A predetermined color correction adjustment value a is set in response to the change in the color adjustment level (S62).

Then, using the value a, the color correction coefficient y,,m-,c,
is changed (S63). That is, Yn"Y+ 8 y! ← y, + a mQ"-1111-a nt ← m, + a Co ← Ct a C2 ← Ct + a Next, when it is determined that the print start key 71 has been pressed ( (YES in S64), the process returns to 953 and printing of the mosaic monitor image is started. At this time, the document image is not scanned, but printing is performed based on the image data in the memory 401 (653 to 555). If you do not want to print (S
64 (No), immediately proceed 571i.

Next, when the user selects a desired image (block) from among the mosaic monitor images on the display unit 84 (S71)
, Km, Kc to the color correction coefficients according to the selected image.
is set (S72).

When the print start key 7I is pressed to request copying (S73), scanning of the original is started, and copying is started using the set color correction coefficients y, m, c (S74). ). and until the end of copying (S75)
), copy, and return.

FIGS. 14(a) and 14(b) are flowcharts for setting coefficients for color adjustment in printing a mosaic monitor image.

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

In this, the counter Ct 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 Ctt 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 print position of the mosaic monitor image, and g represents the distance of one 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 the leading edge of the image (leading edge of paper P) is reached (S301), and when the leading edge of the image has passed, the counter Ct is initialized (5302).
), the state is set to "1" (S303).

When the state is rN, wait until the counter Ct+ becomes T (S311), that is, the mosaic monitor image C
Locus my, the tip of M. Wait for the state to reach the position r, and then change to the state r depending on the color of the toner in the developer used.
2 Jump to either jJ3 J or r4 J.

That is, when Y (yellow) (YES in S312)
sets the state to "2" (S313). When M (magenta) (YES in S321), initialize the counter Ct (9322) and set the variable [to 05323).
, the state is set to "3" (9324). C (cyan)
When (No in S321), the counter Ct.

Initialize 9331) and set variable j to "0"533
2), the state is set to "4" (S333).

When the state is [2], a latch signal is output to the image level setting circuit 2, and y is set as coefficients 1 to 3 in the latches 302, 303, and 304, respectively. +)'++)' Latch t9341), counter CL, hj(T +9d
), that is, the mosaic monitor picture (IGM
Wait until it reaches the position of coordinate yl, which is the rear end of (S34
2), set the state to rOJ (S343).

When the state is "3", m should be substituted for the coefficients i to 3 of latches 302 to 304 (5351), and Ctf
Wait for fi to become Q, i.e. 1 on the mosaic monitor.
Wait until the end of the block (S352), and count the counter C.
tt is initialized (9353), and variable i is incremented by one (S354). Next, it waits until the rear end of the mosaic monitor image is reached (S355), and the state is set to [0] (9356). That is, here, coefficients 1 to 3 have the same @1. is set, and each time the mosaic monitor image changes by l blocks in the sub-scanning direction, coefficients 1 to 3 are changed to a new value 'i+1.

When the state is 4, substitute C1 for coefficients 1 to 3 of latches 302 to 304 (5361) and wait for the counter Ctz to become (3Q), that is, wait for 3 blocks of the mosaic monitor to complete. (8362),
The counter Ct is initialized (5363), and the variable j is incremented by one (S364). Next, it waits until the rear end of the mosaic monitor image is reached (8365), and sets the state to 10'' (S366). That is, here, coefficients 1 to 3 of latches 302 to 304 are set to the same value C1, and each time the co-mosaic monitor image changes by three blocks in the sub-scanning direction, coefficients 1 to 3 are changed to a new value Cj+1. be done.

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

Ctt is incremented (S371).

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

The following margin (effect of the invention) In order to always set the density to the standard value in mosaic monitor mode,
There is less risk of making a mistake in selecting color adjustment.

Further, in this case, since there is no need to use the density setting means in the mosaic monitor mode, the color correction coefficient can be adjusted using the density setting means, and the configuration of the operation panel can be simplified.

[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 diagram of the selector. FIG. 8 is a diagram of the levels of density correction and color correction. FIG. 9 is a circuit diagram of the image tone setting circuit. FIG. 10 is a circuit diagram of the registered image memory circuit. FIG. 11 is a diagram of the main flow related to the mosaic monitor mode of the digital color copying machine. FIG. 12 is a flowchart of image registration processing. FIG. 13 is a flowchart of mosaic monitor output settings. FIGS. 14(a) and 14(b) are flowcharts of interrupt processing. l...Registered image memory circuit, 2...Picture setting circuit,
20... Signal processing unit, 25... CPU170
...Operation panel, 78...Mosaic monitor selection key 79...Density correction key (color correction key), 84...Display section, 401...Memory. Patent Applicant Minolta Camera Co., Ltd. Agent Patent Attorney Aoyama Aoyama and 1 other person Figure 7 Country 8: A 10A Medium B 10C 10D Figure 11 Figure 12

Claims (2)

[Claims] (1) In a digital color copier equipped with a mosaic monitor mode that prints multiple images on the same sheet of paper by applying different color correction calculations to the image data of specific areas in the original image, printing in the mosaic monitor mode A digital color copying machine characterized by being equipped with a density setting means for automatically setting the density level of printing to a standard value when carrying out the printing. (2) The digital color copying machine according to claim 1, further comprising a density setting means by which a user can set the density level, and when the density level is set by the density setting means in the mosaic monitor mode, the print control means , a digital color copying machine is characterized in that a color correction coefficient is set in advance to correspond to the density level.