JPH03265368A - Picture processor - Google Patents

Abstract

PURPOSE:To decrease a difference between an original picture and a picture on a monochroic display device by forming printing color picture signals Y, M, C based on color picture signals R, G, B separating a color picture signal by each color component and forming a monochroic picture signal based on the signals Y, M, C. CONSTITUTION:Each of analog picture signals R, G, B is amplified sequentially serially by an amplifier 102, converted into a digital picture signal by an A/D converter 103, inputted sequentially in latches 104-106, each of the digital picture signals R, G, B is separated in parallel by a color component and outputted from a latch 107. Then the signal is inputted to an RGB/YMC conversion section 108, in which the signal is converted into parallel digital signals Y, M, C and inputted to a YMC/monochroic conversion section 110, in which the signal is converted into a monochroic gradation signal. Thus, the difference between the picture on the monochroic display device and the original picture is reduced.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an image processing device, and for example, to an image processing device that processes color image signals obtained after reading a large color original and performing color separation. It is.

[Prior Art] Conventionally, in this type of device, when displaying color image data obtained after reading a color original and performing color separation on a monochrome display device, a specific color image is displayed on a monochrome display device. One of two methods is used: display using data for one color, or display using data obtained by adding data for each of the three primary colors.

[Problems to be Solved by the Invention] However, in the above conventional example, in the former case, if a specific selected color component does not exist in the document, the image on the monochrome display is significantly different from the read document image.

Furthermore, in the latter case, if each color component exists at the same density throughout the document, the image on the monochrome display device will be significantly different from the read document image.

As described above, since the read original image and the image displayed on the monochrome display device are significantly different, there is a drawback that it is difficult to confirm the read image on the display device.

The present invention has been made in view of the above-mentioned drawbacks of the conventional example, and its purpose is to reduce the difference between an image on a monochrome display device and an original image, and to print it on a color printer. An object of the present invention is to provide an image processing device that can reduce the difference between the image and the image.

[Means for Solving the Problems] In order to solve the above-mentioned problems and achieve the objectives, an image processing apparatus according to the present invention includes an input means for inputting color image signals R, G, and B, and an input means for inputting color image signals R, G, and B. Separating means for separating the input color image signals R, G, B by color component, and color image signals Y, M, for printing based on the respective color image signals R, G, B separated by the separating means. C, and a second forming means that forms a monochrome image signal for monochrome display based on the color image signals Y, M, and C formed by the first forming means. .

[Operation] According to this configuration, the input means receives color image signals R, G.
. H
The second forming means forms a monochrome image for monochrome display based on the color image signals Y, M, and C formed by the first forming means. form a signal.

[Embodiments] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram showing the configuration of a color scanner according to this embodiment. In the figure, 101 indicates a color CCD that optically reads the original image, and lO2 indicates a color CCD.
103 is an A/D converter that converts the analog image signal amplified by the amplifier 102 into a digital image signal;
04.1.times.5, 106 indicate latches each consisting of 5 bits that latch the digital image signal using the latch clock (CLKI). 15 which latches the digital image signal (VDI-VD3) outputted from each latch 104 to 106 with CLK2 indicating a latch clock 107;
It shows a latch made up of bits. The latches 104 to 106 described above are configured to separate the serially arranged R, G, and B digital image signals in parallel according to color components.

108 is an RGB/
A YMC conversion unit is shown, and 109 is an RGB/YMC conversion unit 1.
Parallel digital image signal VD4 output from 08
110 shows a color signal I/F that converts the digital image signal VD5 into the image signal format of a predetermined color printer and outputs it as a serial digital image signal VD7, and 110 converts the parallel digital image signal VD5 into a serial monochrome format by YMC-monochrome conversion of this embodiment. An MMC/monochrome converter that converts into a tone signal VD6 is shown, and 111 is a YMC/monochrome converter 11.
This figure shows a monochrome signal I/F that converts the serial monochrome gradation signal VD6 outputted from 0 to an image signal format suitable for a predetermined monochrome display device and outputs it as a serial monochrome gradation signal VD8.

Next, the operation of this embodiment will be explained.

FIG. 2 is a diagram illustrating the color image reading mode of this embodiment, and FIG. 3 is a timing chart illustrating the signal timing of this embodiment.

An original image formed on the color CCD I Ol by an optical system (not shown) is color-separated by the color CCD 101. As shown in FIG. 2, the color CCD 101 has an R filter, a G filter, and a B filter successively deposited on each pixel of the CCD. Note that a total of three pixels consisting of one pixel each of R, G, and B is defined as a unit of one pixel. R, G, B
Each analog image signal of
The signal is amplified by the A/D converter 103 and further converted into a digital image signal VDO of 5 bits of valid data.

The digital image signal VDO is sequentially input to the latches 104 to 106, and is latched by the latch clock CLKI at the timing shown in FIG. Each latch 104-1
06 output digital image signal VD, 1 to 3 are latch 1
07 and is latched by the latch clock CLK2 at the timing shown in FIG. That is, the digital image signals VD1 to VD3 are latched by the latch clock CLK2 in the states of B, G, and H signals, respectively. Therefore, the parallel digital image signal VD4 output from the latch 107 is a 15-bit (5 bits×3 color components) digital image signal for one pixel.

Next, the parallel digital signal VD4 is RGB/YMC
The signal is input to the converter 108 and converted into Y, M, and C parallel digital signals VD5.

Here we will explain the RGB/MMC conversion method.

In this embodiment, conversion is performed using a conversion method using an RGB-MMC conversion table (not shown), taking into account correction of characteristics of a connected color printer (not shown). Each color 4 whose relationship with density can be approximated by a straight line
A bit MMC dimonochrome signal VD5 is output.

The parallel digital image signal VD5 is a color signal I/
The signal is input to the F processing unit 109, converted into an image signal format suitable for the color printer, and output as a digital image signal VDT for the color printer.

Moreover, the parallel digital image signal VD5 is YMC/
Input to the monochrome converter 110, the monochrome gradation signal VD
6.

Here, details of the YMC→monochrome conversion method will be explained.

FIG. 4 is a block diagram showing the configuration of the MMC/monochrome converter 110 of this embodiment, and FIG. 5 is a diagram illustrating the relationship between density and gradation of each Y, M, and C according to this embodiment. .

In FIG. 4, 41 indicates a ROM. This R.O.
M41 has a general capacity of 256 Kbit, and a parallel digital signal VD5 is applied to addresses AO to A11.
(Each Y.

M, C4 bit signals) are input, and a monochrome gradation signal VD6 is outputted from the data Do-D3 according to the conversion table that has already been set.

Here, a method of setting the above conversion table will be explained.

The parallel digital image signal VD5 is data that has also been subjected to α correction by a printer (not shown), and the relationship between the gradation and density of each color component of the parallel digital image signal VD5 is as follows.
As shown in FIG. 5, it is approximated by a straight line. Here, C=14, M=13. in FIG. The number Y=10 is the relative value of the density when each color is in its darkest state (gradation 15).

Even if the gradation is the same, there is a difference in density depending on the Y, M, and C color components, so when calculating the monochrome gradation, a value that corrects this difference between densities is added. be done. Therefore, a formula for determining monochrome gradation is shown below. That is,. In the ROM41 mentioned above,
A conversion table according to this arithmetic expression (1) is stored.

In this way, the serial monochrome gradation signal VD6 obtained from the conversion table is the sum of signals corrected for Y, M, and C density differences.

Further, the serial monochrome gradation signal -V D 6 is input to the monochrome signal I/Fill, where it is converted into a signal format suitable for a monochrome display device (not shown), and is further output as a serial monochrome image signal VD 8 for the monochrome display device. Output.

Serial monochrome image signal VD obtained in this way
By displaying on a monochrome display device (not shown) using T, the image displayed on the monochrome display device is
An image that has a small difference from the original image and a small difference from the image printed by the printer is displayed.

In this way, the difference between the image on the monochrome display device and the original image is reduced, and the difference between the image and the image printed by a color printer can also be reduced.

In other words, it is easy to read and confirm the image to be printed on a monochrome display device.

Now, in the above-described embodiment, the configuration is such that only one type of color printer (not shown) is compatible, but the present invention is not limited to this, and the first color printer is compatible with a plurality of color printers. A plurality of conversion tables are set in the configuration of the RGB/YMC conversion unit 108 shown in the figure, and a corresponding conversion table is also set in the MMC/monochrome conversion unit 110, so that both tables can be switched simultaneously using a DPSW or the like. Just set it up. In this way, it is possible to obtain a configuration that is compatible with a plurality of color printers.

Further, in the above-mentioned embodiments, the configuration of a single scanner has been described, but the present invention is not limited to this, and may be incorporated into a color printer or a monochrome display device.
Alternatively, it may be used by being incorporated into a device including a color printer and a monochrome display device.

[Effects of the Invention] As described above, according to the present invention, the difference between an image on a monochrome display device and an original image can be reduced, and the difference between an image printed by a color printer can also be reduced. In other words, it is easy to read and confirm the image to be printed on a monochrome display device.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the configuration of the color scanner of this embodiment, Fig. 2 is a diagram explaining the color image reading form of this embodiment, and Fig. 3 is a timing diagram explaining the signal timing of this embodiment. 4 is a block diagram showing the configuration of the MMC/monochrome converter 110 of this embodiment, and FIG. 5 is a diagram illustrating the relationship between density and gradation of each Y, M, and C according to this embodiment. . In the figure, 41...ROM, 101...CCD, 102
... Amplifier, 103 ... A/D converter, 104
~107...Latch, 108...RGB/YMC converter, 109...Color signal I/F, 110...Y
MC/monochrome converter, 111...monochrome signal I/
It is F.

Claims (3)

[Claims] (1) an input means for inputting color image signals R, G, and B; a separation means for separating the color image signals R, G, and B input by the input means into color components; Each color image signal R, G, B
a first forming means for forming color image signals Y, M, and C for printing based on the color image signals Y, M, and color image signals Y, M formed by the first forming means;
, and a second forming means for forming a monochrome image signal for monochrome display based on C. (2) The second forming means includes a correction means for correcting the density difference between the color image signals Y, M, and C formed by the first forming means. The image processing device described. (3) The image processing apparatus according to claim 2, wherein the correction means forms a table of information for correcting the density difference.