JPS63193771A - Color image processing device - Google Patents

Abstract

PURPOSE:To reduce a storage capacity, by restoring a color code and a multilevel density data based on output data obtained by accessing to the same addresses of plural memory planes simultaneously, and reproducing an image based on those restored data. CONSTITUTION:When a color image is separated to plural chrominance signals, it is stored in prescribed memories 151-155 after separating a data of one picture element to a color code data and a density data, and when a storage data is stored in a memory device 160 finally, the color code and a density information corresponding code (code representing binarization or three-value formation) are stored. And, based on the output data obtained by accessing to the same addresses of the plural memory planes simultaneously, a bit of color information and a bit of density information are restored, and based on those restored data, the image is reproduced. Therefore, it is possible to reduce the storage capacity of an external memory device, and furthermore, by providing a data conversion circuit 410, it is possible to easily and exactly, reproduce a storage data stored in the memory device 160.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a color image processing device suitable for application to a simple electrophotographic color copying machine, etc., particularly when reusing stored image data. The present invention relates to a color image processing device suitable for recording processing, etc.

[Background of the Invention] Color image processing devices that optically read image information from a document or the like and record it on recording paper using an output device such as an electrophotographic color copying machine are already known. .

When using an electrophotographic color copying machine as an output device, color image information such as a document is usually converted into multiple color information (including achromatic colors), and based on this color information, electrostatic latent images, electrostatic Development and fixing processing is performed.

This color information is supplied not only to the output device but also to an external storage device and stored temporarily, and is configured so that it can be reused by reading the data at an appropriate time at a later date.

When such an external storage device is provided, image information is generally stored in a signal format that can be supplied to the output device. Therefore, as a signal processing system for converting image information into a plurality of color information, a circuit system as shown in FIG. 19 is sometimes used.

Here, in the example shown below, color image information such as a manuscript is
Once separated into two color separated images of red R and cyan Cy by the optical system, three color signals R of red, blue and black are then separated.
, B, and BK.

In FIG. 19, a terminal 150a is supplied with a red signal ε R (its level is VR) normalized by a white signal, and a cyan signal (also normalized by a white signal) is supplied to a terminal 150b. Similarly, the level VC) is supplied.

The red signal VR and cyan signal VC are supplied to memories 151 and 152 as their address signals in order to be separated into three color signals.

Here, in order to separate two color signals into three color signals, a color information map constituted by a color difference signal axis and a luminance signal axis is used. That is, by performing appropriate color difference signal processing, a single color signal can be calculated from the color difference signal level and the luminance level.

Therefore, first, each level of the color difference signal (VC/VR+VC) and luminance signal (VR+VC) must be calculated from the two color signals VR and VC, so the memories 151 and 152 that store data indicating the calculation results is provided. Then, the input red signal and cyan signal VR,
VC becomes an address signal, and each data indicating the corresponding color difference signal and luminance signal can be accessed.

The corresponding color signals are addressed by the color difference signals and luminance signals completely read out from the memories 151' and 152.

Therefore, the color separation map that should be obtained using the color separation map described above is
A plurality of memories 153 to 155 are provided in which data of each color signal is independently stored, and the above-mentioned color difference signal and luminance signal are supplied as respective address signals.

The read color signals R-BK are respectively sent to buffers 156 to 156.
The data is supplied to a color copying machine via 158 or to a storage device 160 as shown in the figure, where the data is stored. The illustrated example shows a case where the storage device 160 is composed of three memories 161 to 163 provided corresponding to color signals.

Note that 140 indicates an oscillator for obtaining transfer pulses used as drive signals for the image reading system. The output is also supplied to the address counter 141, and the addresses of the memories 161-163 are controlled by the address data. In addition, the buffers 156 to 158 and the memories 161 to 163 are controlled by the control signal SC supplied to the terminal 142.
The active state of can be controlled.

[Problems to be Solved by the Invention] By the way, when separating color difference information and luminance information into three color information in this way, these three color information themselves are stored in the storage device 160. There are the following problems.

That is, for example, A4 size (297mm x 210mm)
image information with a resolution of 16 dots/mm.
When trying to separate colors and store them as binary data, 29
7mmX 210mmX (16dots/mm)"X
A storage device 160 with 3 colors = 47900160 bits and a storage capacity of 6 Mbytes must be prepared.

Therefore, it is necessary to use a fairly large storage device 160. When applied to a color image processing device that is capable of recording image information that is roughly larger than A4 size, a storage device with a roughly larger capacity must be used.

To solve this problem, it is necessary to convert image information with multiple colors into color information (hereinafter referred to as a color code) and density information, and store the image information based on this color code. Bye.

At that time, the density information is once binarized, and the color code (binary data) is controlled by the binarized density data (BI
be done.

Therefore, the image data that is finally stored is data that indicates a color code.

Therefore, in order to convert into three color signals and store the color information in memory, it is sufficient to use a storage device having the storage capacity as shown below.

As mentioned above, the resolution of A4 size is 16 dots/m.
m, when decomposing into three color signals, the code indicating color designation (color code) has 2 pits (red, blue,
In this example, 297 mm x 210 mm x (16 dots/mm) is sufficient.
2×2 pits=31933440 bits': A storage device 160 with a storage capacity of 4 Mbytes may be prepared.

From the above, it is clear that by configuring in this way, it is possible to achieve a reduction in storage capacity.

By the way, when configured to store data indicating color codes, especially when configured to store three levels such as white, black, and gray at the same time, it is possible to simply read out the stored data. By itself,
It is not possible to reproduce the desired image information.

This is because, along with the stored data indicating the color code, the density information corresponding signal (multi-value information) for identifying whether the data is binary data or ternary data is also included.

Therefore, the present invention proposes a color image processing device that solves these problems with a simple structure, reduces memory capacity, and has a reproduction processing system that can reproduce the data without error. .

[Technical means for solving the problem] In order to solve the above-mentioned problem, the present invention converts image information into a color code and density information, and then stores the image information in a storage device consisting of a plurality of memory planes. In a color image processing device designed to be able to store data, the color code and multi-level density data are restored based on output data obtained by accessing the same address of multiple memory planes simultaneously, and the color code and multi-level density data are restored based on these restored data. It is characterized in that the image is reproduced using the same method.

[Function] Image information having a plurality of colors is converted into a color code and density information, and stored based on this color code.

The density information is once converted into an a value. A color code (binary data) is controlled by this binary data.

Therefore, the image data that is finally stored is data that indicates a color code. In addition to binary data, concentration information corresponding signals indicating multi-value data such as ternary data are stored.

Specifically, desired image data is stored in the following manner.

When binarized density data exists, color code data corresponding to the image data is stored, and when density data does not exist, color code data corresponding to white is stored.

In addition, since there is a color code indicating a white code in the color code data, by using this, one pixel's multivalued data, that is, a 3-color ternary image, can be expressed in 3 bits including the color code. be able to. Therefore,
Three memory planes are prepared as storage devices.

The storage data stored in this manner is reproduced to reproduce the original image based on the following logical configuration.

First, colors can no longer be specified externally. The same address in multiple memory planes is then accessed simultaneously. Among the data read out, if the color code data matches the color specification data, that color code data is output, and at the end of the mismatch, color code data (0, 0) indicating white is output. can be output.

Furthermore, when the read color code data is the color code (11) indicating white, the color code data (0°0) indicating white is output regardless of the color specification.

When the color code data matches the color specification data and the read density information corresponding signal (multi-value identification data) is ○, 51 degree data <0.1) indicating the gray level is output. , 1, density data (1, 0) indicating the black level is output. On the contrary,
When the color code data does not match the color designation data, white level density data (◯, O) can be output.

This reproduces multivalued information. The density data is used as latent image control No. 13 for the photosensitive drum (image forming body).

As mentioned above, the resolution is 16 dots for A4 size.
s/mm, and when decomposing into three color signals, 2 bits (red, blue, black, and white) are sufficient for the code indicating the color (color code), so in that case, approximately 4M
A storage device 160 with a storage capacity of bytes may be prepared.

[Example] Next, a color image processing apparatus according to the present invention will be explained in detail with reference to FIG. 1 and the following figures.

However, the embodiment shown below is a case where the present invention is applied to a color image processing apparatus using an electrophotographic color copying machine as an output device.

Therefore, first, a schematic configuration of such a color image processing apparatus to which the present invention can be applied will be explained with reference to FIG.

Image information such as a document is subjected to shading correction processing, color separation processing, A/D conversion processing, and other image processing in the image reading device 50, so that image data with a predetermined number of pits corresponding to each color signal, for example, 16 gradations (0~
F) image data.

Each image data is subjected to image processing such as enlargement/reduction in an enlargement/reduction circuit 2 based on a linear interpolation method. In this case, the interpolation data used as the image data after the enlargement/reduction processing is stored in an interpolation table (interpolation ROM), and the signal for selecting this interpolation data is the image data before the enlargement/reduction processing and the data Interpolation selection data stored in ROM is used. Necessary interpolation selection data is selected based on a command from the system control circuit 8° in accordance with the specified magnification.

The image data after image processing is supplied to the output device 65,
The image can be recorded at the magnification set externally. Output device 6
5, an electrophotographic color copying machine or the like is used.

Image data obtained from the image reading device 50 or image data after image processing is stored in the storage device 160.

The image reading device 5o is equipped with a drive motor, an exposure lamp, etc. for driving the image reading means, and these are controlled at predetermined timing by command signals from the sequence control circuit 70. Data from a position sensor (not particularly shown) can be input to the sequence control n circuit 7o.

In the operation/display section 75, various input data such as magnification designation, recording position designation, recording color designation, etc. are input, and the contents thereof are displayed. For example, when a recording color is designated, the corresponding storage data among the storage data stored in the storage device 160 is output, and an image is completely recorded based on this.

This image can also be displayed on a CRT or the like.

The system control circuit 80 controls each side mentioned above, controls the entire image processing device, and manages the state.
Therefore, microcomputer control is appropriate for this system control.

The figure shows an example of microcomputer control, and necessary image processing data and control data are exchanged between the control circuit 80 and the various circuit systems described above via a system bus 81.

Image reading start 4 is sent to the image reading device 50.
No. 8, a start signal for shading correction, etc. are supplied via the system bus 81.

Magnification data and the like specified on the operation/display section 75 are input to the control circuit 80 and then supplied to the enlargement/reduction circuit 2 via the system bus 81.

Incidentally, the binarization process of image data is performed by this enlargement/reduction circuit 2.
However, in the present invention, the binarization process is performed on the image reading device 50 side.

In that case, threshold data for binarization can be selected depending on the type, density, etc. of the image to be recorded. This threshold data selection command signal is supplied via the system bus 81.

The output device 65 can be supplied with a start signal for image recording, a recording paper size selection signal, a recording color designation signal, and the like.

Next, these components will be explained in detail.

For convenience of explanation, an example of the configuration of an easy-to-understand color copying machine to which the present invention can be applied will first be described with reference to FIG.

The illustrated color copying machine attempts to record a color image by separating image information into three types of colors. As described above, black BK, red R, and blue B are exemplified as the three types of colors to be separated.

In FIG. 2, 200 is an example of a main part of a color copying machine, and 201 is a drum-shaped image forming body, the surface of which is covered with a photoconductive photoreceptor surface layer of selenium Se, OPC (organic semiconductor), etc. is formed, and an electrostatic image (electrostatic layer property) corresponding to the optical image can be formed.

The following members are sequentially arranged on the circumferential surface of the image forming body 201 in the direction of rotation thereof.

The surface of the image forming body 201 is uniformly charged by a charger 202, and then the surface of the image forming body 201 is subjected to image exposure based on each color separation image (the optical image thereof is indicated by 204).

After image exposure, the image is developed by a predetermined developing device.

The developing devices are arranged in a number corresponding to the color separated images.

In this example, the developing device 20 is filled with red toner developer.
5, a developer 206 filled with blue toner developer, and a developer aM 207 filled with black toner developer.
They are sequentially arranged facing the surface of the image forming body 201 in this order in the rotation direction of the image forming body 201.

The developing devices 205 to 207 are sequentially selected in synchronization with the rotation of the image forming body 201. For example, by selecting the developing device 207, toner adheres to an electrostatic image based on a black color separation image, thereby changing the color of black. The separated images are developed.

A pre-transfer charger 209 and a pre-transfer exposure lamp 210 are provided on the developing device 207 side, and these make it easy to transfer the color image onto the recording medium P.

However, these pre-transfer charger 209 and pre-transfer exposure lamp 210 are provided as necessary.

The color image or monochrome image developed on the image forming body 201 is transferred onto the recording medium P by the transfer device 211. The transferred recording material P is subjected to a fixing process by a fixing device 212 at a subsequent stage, and then the paper is ejected.

Note that the static eliminator 213 consists of one or a combination of a static elimination lamp and a corona discharger for static elimination, and these are provided as necessary.

The cleaning device 214 includes a cleaning blade and a fur brush, and is used to remove residual toner adhering to the drum surface after the color image of the image forming body 201 has been transferred.

It is well known that this removal operation is performed so that the surface of the image forming member 2010 is separated by the time the developed surface is reached.

As the charger 202, a scorotron corona discharger or the like can be used. This is because the influence of previous charging is small and stable charging can be applied to the image forming body 201.

As the image exposure 204, image exposure obtained from an optical system having a laser beam scanner can be used.

This is because a laser beam scanner can record clear color images.

For at least the second and subsequent development steps that are repeated to superimpose the color toner layers, it is necessary to ensure that the toner that has adhered to the image forming body 201 due to the previous development is not displaced during the subsequent development. . In this sense, it is preferable that such development is performed by non-contact two-component jumping development.

FIG. 2 shows a type of developing device that performs development by such non-contact two-component jumping.

As the developer, it is preferable to use a so-called two-component developer. This is because this two-component developer has clear colors and can easily charge the toner.

FIG. 3 shows an example of the image reading device 50. As shown in FIG.

In the figure, color image information (optical image) of a document 52 is separated into two color separated images by a dichroic mirror 55. In this example, the red R color separation image and the cyan ay
It is separated into color separated images.

Therefore, the cutoff of the dichroic mirror 55 is 5
A material with a wavelength of about 40 to 600 nm is used.

As a result, the red component becomes transmitted light, and the cyan component becomes reflected light.

The color separation images of red R and cyan ay are respectively supplied to image reading means 56 and 57 such as CCD, and image signals of only the red component R and cyan component cy are output from each image reading means 56 and 57, respectively.

FIG. 4 shows the relationship between the image signals R, cy and various timing signals, including the horizontal effective area signal (H-VA'LID).
(Figure C) Let CCD 56, 57 c7)
Corresponding to the maximum original reading width W, the images shown in F and G of the same figure (3I signals R and cy are synchronized clocks CLKI (E of the same figure)
is read out in synchronization with

The image signals R and cy are supplied to A/D converters 60 and 61 via normalizing amplifiers 58 and 59, and are converted into digital signals having a predetermined number of pits.

This digital image signal is subjected to shading correction. 63
．． Reference numeral 64 indicates a shading correction circuit having the same configuration. A specific example will be described later.

The shading-corrected digital color image signal is supplied to the next stage color separation circuit 150, where it is divided into a plurality of color signals R, B, and BK necessary for color image recording. These color signals R, B, and BK are each composed of color coat data and density data.

As described above, since the image forming process is such that one color image can be developed per rotation of the image forming body 201, the developing unit 205 is operated in synchronization with the rotation of the image forming body 201. 207 is selected, and the corresponding color signals are sequentially selected and output.

In devices that read images by illuminating a document with a lamp and condensing the reflected light with a lens, a non-uniform optical image called shading is obtained due to optical problems with the lamp, lens, etc.

In FIG. 5, image data in the main scanning direction are Vl and V2.
...Vn, the level decreases at both ends in the main scanning direction. Therefore, in order to correct this, the shading correction circuits 63 and 64 perform the following processing.

In Figure 5, VR is the maximum side value at the image level, and ■1 is the white color of a reference white board (not shown) with uniform density.
The image level is purple. In fact, if the image level when the image is read is dl, then the gradation level d1' of the corrected image is as follows.

di'=dlXVR/Vl Correction is performed for each pixel image data so that this correction formula holds true.

FIG. 6 shows an example of the shading correction circuit 63.

The first memory 66a, which is composed of a RAM or the like, stores (3
This is a memory for reading the code (shading correction data).

The second memory 66b is for correcting the image data based on the shading correction data stored in the first memory 66a when reading an image, and a ROM or the like is used.

In the shading correction, first, one line of image data obtained by scanning a white plate is stored in the first memory 66a. When reading an image of a document, the image quality data is supplied to the address terminals AO to A5 of the second memory 66b, and the shading correction data read from the first memory 66a is supplied to the address terminals A6 to All. . Therefore, the second memory 66b outputs image data that has undergone shading correction according to the above-mentioned arithmetic expression.

The above-mentioned color separation (color separation into three color signals from two colors) is performed based on the following idea.

Figure 7 schematically shows the spectral reflection characteristics of a color chart of color components, in which Figure A shows the spectral reflection characteristics of achromatic colors, Figure B shows the spectral reflection characteristics of blue, and Figure 7 shows the spectral reflection characteristics of blue. C shows red spectral reflection characteristics.

The horizontal axis shows wavelength (nm), and the vertical axis shows relative sensitivity (%). Therefore, the spectral characteristics of the dichroic mirror 55 are set to 6.
00nm, the red component R is transmitted and the cyan component cy
is reflected.

The level of the red signal R normalized with white as the reference is VR,
When the level of cyan No. 18 cy is set to VC, a coordinate system is created from these signals VR and VC, and red, blue, and black colors are separated based on the created color separation map.

When determining the coordinate axes, the following points need to be considered.

(2) In order to be able to express halftones, the concept of reflectance (reflection density) of the original 52, which corresponds to the luminance signal of the television signal, is adopted.

Introduces the concept of color difference (including hue and saturation) such as TI, red, and cyan.

Therefore, the following may be used as the luminance signal information (for example, a 5-bit digital signal) and the color difference signal information (also a 5-bit digital signal).

Luminance signal information = VR + VC... (1) However, 0≦VR≦1゜0... (2) 0≦VC≦
1.0... (3) 0≦VR+vC≦2
．． 0 --- (4) VR, VC+7) Sum (VR+
VC) Lt Black level (=0) to white level (=2.0)
All colors exist in the range 0 to 2.0.

Color difference No. 48 information = VR / (VR + VC) Mataha VC / (
VR+VC)---(5) In the case of an achromatic color, the proportions of the red level VR and the cyan level VC included in the overall level (VR+VC) are constant. Therefore, VR/(VR+VC)=VC/(VR+VC)=0.5
... (6) becomes.

On the other hand, in the case of chromatic colors, 0.5<
VR/(VR+VC)≦1.0... (7)0≦v
C/(VR+VC)<0.5... (8) For cyan colors, O≦VR/(VR+VC)<0.5... (9)
0.5<VC/(VR+VC)≦1.0... (10
) can be expressed as follows.

Therefore, the coordinate axes are (VR+VC) and vR/(VR+
vC) or (VR+VC) and VC/(VR+V
By using a coordinate system having C) as two axes, it is possible to clearly separate chromatic colors (red and blue light) and achromatic colors just by level comparison processing.

In FIG. 8, the vertical axis shows the color difference signal component (VR + VC), and the horizontal axis shows the color difference ε component vC/(
The coordinate system when VR + VC) is taken is shown.

If VC/(VR+VC) is used as the color difference A8 component, the area smaller than 0.5 will be red light R, and the area larger than 0.5 will be blue light B. Achromatic colors exist in the vicinity of color difference signal information=0.5 and in areas with little luminance signal information.

In this way, by detecting the levels of the red signal R and the cyan signal Cy, from the color information signal of the color document,
The three color signals R1B and BK of red, blue, and black can be separated and output.

FIG. 9 shows a specific example of a color separation map in which colors are classified according to such a color separation method. The quantized density corresponding values obtained from the reflection density of the original 52 are fully stored in this ROM table. The illustrated example is divided into 32×32 blocks.

In fact, ROMs for the number of colors to be separated may be prepared, or ROMs storing corresponding map data may be used. Details will be described later.

FIG. 10 is a system diagram of essential parts showing an example of a color separation circuit 150 for realizing such color separation.

In the figure, a red signal R and a cyan signal cy before color separation into three colors are supplied to terminals 150a and 150b.

For these colors No. 13, those that have not undergone processing such as gradation conversion and 7 correction can be used.

The data after the arithmetic processing is used as an address signal for the memory 152 in which the arithmetic results of (VR+VC) for obtaining luminance signal data are stored, and the arithmetic results of the color difference signal data VC/(VR+VC). It is used as address No. 45 for the memory 151 in which is stored.

These memories 151. ．． Each output of 152 is connected to a separate memory (
It is used as an address signal for ROM configuration) 153 to 155. Memory 153 is for red light R, and memory 15
4 is for the green signal B, and memory 155 is for the black signal BK.

The memories 153 to 155 contain, in addition to the color separation map data shown in FIG. 9, that is, the density data (4-bit configuration).
Each color code data (2-bit configuration) as shown below is stored.

When we consider red and blue as chromatic colors as described above, each color information itself can be represented by 2 bits, so if we now assume that the density data D shown in FIG. ~155 instead of being stored in
In addition to this density data D, color coats 1, 2,
3. O are stored together in respective memories 153-155. Therefore, data of OD...black (memory 155), 2D...red (memory 153), and D...blue (memory 154) can be stored respectively.

An example of the stored state is shown in FIG. Same figure (A) to (C)
In the figure, the shaded area is the data storage area, and X indicates density data. The density data X is a hexadecimal number.

Color code data "30" indicating white is stored in areas other than the shaded area.

Then, the image data (color code data and density data) sequentially read out from each of the memories 153 to 155 is supplied to a color ghost removal circuit 300 to perform ghost processing.

Here, color ghost processing of color information is performed on color code data. The color itself is changed by the color code data, and in some cases, the color level is changed by the density data.

Of the image data output from the color ghost removal circuit 300, the density data is binarized by the binarization means 171 forming the storage data processing circuit 170. Therefore, the binarization means 171 binarizes the 4-bit density data based on the threshold data from the threshold ROM 172.

Furthermore, when this binarized binary data exists, the color code corresponding to the image frame data is stored in the storage device 160.

When binary data does not exist, the color code corresponding to white is stored in memory.

Therefore, as shown in the figure, the color code 1.
At the same time, the binary data is supplied to the inverter 17
After completing the phase inversion at step 3, the control signal 311 (number U) is supplied to the white code generator 174.

Here, when there is no data after binarization, that is, when the background is white, binary data of "L" is obtained from the binarization means 170, and from this it is possible to determine what kind of color code data it is. Even if there is, it can be converted to white color code data and output.

If post-binarized data exists, the input color code data itself will be output.

The white code generator 174 can use a logic circuit or a ROM. If a logic circuit is used, its truth table will be as shown in FIG.

In this way, the density data and color code data are converted into 2-bit image data (hereinafter referred to as stored data) and output from this white code generator 174, so a storage device that stores this stored data is required. 160 includes two memory planes 160A as shown in the figure.
, 160B may be used.

In this case, one memory 160A is a memory for lower bits of stored data, and the other memory 160B is a memory for upper bits.

Note that one memory plane can store a desired image size as binary data. Dynamic RAM or static RAM can be used as the memory plane.

As mentioned above, when color information is stored in memory as color code data, the capacity of the memory plane is 297 mm x 210 mm x (16 dots/mu)
2.times.2 bits=31933440 bits"-4 MB, and the storage capacity of the storage device 160 can be significantly reduced compared to the conventional method.

Now, as mentioned above, in the case of a 2-bit color code, it is possible to store image data in 4 colors, so when the color code is composed of 3 bits, it is possible to store image data in 8 colors (including white). ) can store image data in memory. In this case, the conventional method requires seven memory planes, but if the process of the present invention is performed, only the number of color code pits, that is, 38 memory planes are required. As a result, the storage capacity of the storage device 160 can be reduced to 1/2 or less.

FIG. 13 shows an example in which density data is converted into three values.

Normally, at least 2 bits are required to display 3-value data, but as is clear from the previous examples, there is a color code that indicates a white code, so if you use this, One bit is enough.

In other words, for codes other than songs, when the ternary code is "H", it is at the 3-level level, and when it is °L, it is at the binary level, so the binary code and the ternary code are ,
It becomes possible to make a sharp distinction using 1 bit of data.

However, as is clear from the previous example, the color code requires 2 bits. Because of this, data for one pixel can be expressed with 3 bits including the color code. As a result, it becomes possible to store up to three-color ternarized images by using only three memory planes.

This is because when applying a normal method, only three-color binarized images can be stored.

Therefore, the stored data processing circuit 170 is configured as shown in FIG.

Binary data P2 binarized by the binarization means 171 and 4
The density data of the bits are each supplied to the ternarization means 175, and the binary data P2 is ternarized based on the threshold value data from the threshold value ROM 176. The ternary data P1 and the binary data P2 are supplied to an AND circuit 177, and its 1-bit output (signal corresponding to concentration information) P3 is stored in the third memory plane 160c. Depending on this data content, 2
A distinction is made between value data and ternary data.

Further, the ternary data P1 and the binary data P2 can be roughly supplied to the NOR circuit 178, and the own code generator 174 can be controlled by the output P4.

Here, the relationship between the data P1 to P4 is as shown in FIG. 14. Actually, the information is color information, but for convenience of explanation, ternary levels are illustrated for three colors of luminance information (white, black, and gray).

According to this, since the white level is P4 or "°H", a white code is obtained from the white code generator 174 as in the case of FIG. 10. At this time, P3 is "°L°". It is.

At gray level, P4. Since P3 is both °L゛°, the input color code is directly transferred to memory plane 160.
a, 160b. Therefore, the lower code of the color code remains as °°L°°.

To adjust the black level, P3 is °゛H°" and P4 is L°"
Therefore, the color code is stored in memory plane 1 as is.
60a and 160b. In this case, since its lower code is °H゛°, it can be easily determined that it is a ternary level.

The present invention proposes a processing system that can satisfactorily reproduce such stored data stored in the storage device 160.The storage device 160 may be the embodiment shown in FIG. The effect is particularly noticeable when applied to a device using three memory planes 160A to 160C as shown in FIG.

Now, if the stored data read from each memory plane 160A to 160C is a''-'c, the same address of these memory planes 160A to 160C can be accessed simultaneously to obtain output data as shown in FIG. It is assumed that

As is clear from the figure, even if the output data is the same, it may be binary data or ternary data depending on the data C corresponding to the concentration information. need to be considered.

FIG. 16 shows an example of a reproduction processing system, particularly a reproduction processing system including a recording system, which has been designed with such data reading in mind. The recording system shown in FIG. 2 is used.

First, a color designation signal for designating a color to be reproduced is supplied to the terminal 403 in the operation/display section 75 . As described above, the same code as the code shown in equation (11) can be used as the color designation signal.

The color designation signal is decoded in a decoder 402,
The driving states of the corresponding developing units 205 to 207 are controlled by the output. For example, when red is specified,
The red developer 205 is driven to develop an electrostatic latent image corresponding to the red color separation image.

The color designation signal is also supplied to data conversion circuit 410.

The data conversion circuit 410 includes a color code conversion circuit z111 and a density conversion circuit 412.
1 includes the above-mentioned color designation signal, a memory plane 160A,
The stored data a and b read from the output terminal 413 are supplied, and the color conversion data (output color code data) is output from the output terminal 413, and the coincidence number 3 S is supplied to the density conversion circuit 412. be done.

The density conversion circuit 412 identifies binary data and ternary data from the stored data C read out from the memory plane 160C and the coincidence signal S, and outputs the corresponding density data. There is.

The color code conversion operation and density conversion operation are performed as follows.

When the color code data a and b read from the memory planes 160A and 160B match the color specification data, the color code data a and b are output, and when they do not match, the color code data indicating white (that The code becomes (1, 1)) can be output.

In addition, if the color code data a and b that have been read out are the color code (1, 1) indicating white, the color code data (1, 1) indicating white will be output regardless of the color specification. be done.

When the color code data matches the color designation data, the match signal S becomes 1. At this time, when the read storage data C is O, density data (0, 1) indicating the gray level is output, and when it is 1, density data (1, 0) indicating the black level is output.

On the other hand, when the color code data does not match the color specification data, the white level density data (1, 1
) is output.

This reproduces multivalued information. FIG. 17 shows a truth table of output color code data and output density data when black is specified.

The output density data is used as a latent image control signal for the image forming member (photosensitive drum) 201.

The color code data obtained at the terminal 413 is used as a color image t! for a CRT or the like. RIIJ Used as a control signal.

The density data obtained from the density conversion circuit 412 is sent to the optical system 4.
20.

In this example, the optical system 420 uses laser light. Therefore, the concentration data is
1 to the laser light source 422 as a control signal 18 (light modulation signal), and the intensity and excitation time of the laser light are controlled according to the concentration data. For example, when the level is gray, the intensity of the laser light can be controlled to be lower than when it is at the white level.

The laser beam modulated according to the concentration data passes through an optical lens system 423 to a deflection system (laser beam scanner) 424.
guided by. Now, by deflecting the laser light in the main scanning direction, electrostatic charges 11 corresponding to this density data are formed on the image forming body 201.

On the other hand, the color designation signal is also supplied to the developing units 205 to 207, and since the corresponding developing unit is in a standby state, color development is performed by the selected developing unit. For example, when the color designation signal is red, the red developer 205 is driven;
Since it is developed with red toner, by fixing it, a red recorded image is reproduced.

FIG. 18 shows an example of the color ghost removal circuit 300 described above. The color ghost processing is performed not only in the main scanning direction (horizontal scanning direction) but also in the sub-scanning direction (vertical scanning direction), which is the rotation direction of the 1-forming body 201.

In this example, horizontal and vertical ghosts are removed using image data for 7 pixels in the horizontal direction and 7 lines in the vertical direction.

Color ghost processing applies only to color codes of image data.

Therefore, the color codes read from the memories 153 to 155 are sequentially supplied to the 7-bit shift register 301 and parallelized. The parallel color code data for seven pixels is supplied to the horizontal ghost removal ROM 302, and ghost removal processing is performed for each pixel.

When the ghost processing is completed, the data is latched by the latch circuit 303.

On the other hand, the density data output from the memories 153 to 155 is transferred to the shift register 305 for timing adjustment.
Data transfer conditions are determined such that the density data is serially transferred following the color code data.

The serially processed color code data and density data are supplied to the next stage line memory section 310.

This line memory section 310 is provided to remove vertical color ghosts using seven lines of image data. Note that the line memory is used for a total of 8 lines, but this is because one extra line is used for ghost processing in real time.

The color code data and density data for 8 lines are separated in the subsequent gate circuit group 320, respectively. In the gate circuit group 320, gate circuits 321-328 are provided corresponding to the line memories 311-318, respectively.

The output data of the 8 line memories synchronized in the line memory section 310 is sent to the gate circuit group 320.
The separated color code data is completely separated into color code data and density data, and the separated color code data is supplied to the selection circuit 330, and the color code data data of seven line memories necessary for color ghost processing out of a total of eight line memories is sent to the selection circuit 330. is selected. In this case, when line memories 311 to 317 have been selected, the selected line memories are sequentially shifted such that line memories 312 to 318 are selected at the next processing timing.

The selected and synchronized 7-line memory worth of color code data is sent to the next vertical ghost removal ROM.
340 to remove vertical color ghosts.

Thereafter, it is latched by the latch circuit 341.

On the other hand, the density data separated by the gate circuit 8.320 is directly supplied to the latch circuit 342, and is output after timing adjustment with the color code data.

[Effects of the Invention] As explained above, according to the present invention, when separating a color image into a plurality of color signals, data of one pixel is separated into color coat data and 0 degree data and then stored in a predetermined memory. When the memory data is finally stored in the memory\2 location, this color code and density information correspondence code (code indicating binarization or ternarization) are stored. be.

Therefore, according to the present invention, the storage capacity of the external storage device can be significantly reduced compared to the conventional method.

In this case, the storage capacity can be reduced as the number of color signals to be separated increases, so the effect of the present invention becomes more significant as the number of separated colors increases.

Further, according to the present invention, since the data conversion circuit is provided, the data stored in the storage device can be easily and accurately reproduced.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing an overview of a color image processing device according to the present invention, FIG. 2 is a configuration diagram showing an example of a simple electrophotographic color copying machine, and FIG. 3 is a system diagram showing an example of an image reading device. Figure 4 is a waveform diagram to explain its operation, Figure 5 is an explanatory diagram of shading correction, Figure 6 is a system diagram showing an example of a sequence control circuit, and Figures 7 and 8 are color separation. FIG. 9 is a diagram showing an example of a color separation map; FIG. 10 is a system diagram showing an example of a color separation circuit and a storage device which are the main parts of the signal processing system that is the premise of the present invention;
FIG. 11 is a diagram showing the memory storage situation to explain its operation, FIG. 12 is a diagram showing the truth table of the white code generator, FIG. 13 is a system diagram showing another example of FIG. 10, and FIG. 15 is a diagram for explaining the logical operation at that time, FIG. 15 is an explanatory diagram of data read from the storage device, FIG. 16 is a system diagram showing an example of the main part of the signal processing system of the present invention, and FIG. 17 is an explanatory diagram of the truth table when black is specified, and FIG. 18 is an explanatory diagram of the truth table when black is specified. Separation circuits 151 to 155...Memory 160...Storage device 170...Stored data processing circuit 300...Color ghost removal circuit 410...Data conversion circuit 411...Color code conversion circuit 412... Density conversion circuit 420... Optical system patent applicant Roku Konishi Photo Industry Co., Ltd. Figure 5 Figure 6 ξ3. : Schöte 1ng #414 Co-encounter & Figure 7 A [3 Figure 11 Figure 12 Figure 14 Figure 15 Figure 17

Claims (4)

[Claims] (1) A color image processing device in which image information is converted into color information and density information, and the image information is stored in a storage device consisting of a plurality of memory planes based on these information, The above color information and density information are restored based on the output data obtained by simultaneously accessing the same address of the plurality of memory planes, and the image is reproduced based on these restored data. Characteristic color image processing device. (2) The color image processing apparatus according to claim 1, wherein the density information is created from a restored color designation signal and a signal read from the memory plane. (3) The color image processing apparatus according to claim 1, wherein a binary or multivalued output is used as the density information. (4) After the density information is binarized, it is multivalued, and the multivalued output is stored in a memory plane, and the color information to be stored is controlled by this multivalued output. A color image processing apparatus according to claims 1 and 2, characterized in that: