JPH0646775B2 - Image processing device - Google Patents

Description

The present invention relates to an image processing apparatus for processing input image data.

[Prior Art] Conventionally, as a facsimile machine with a copy function, for example, one described in Japanese Patent Application Laid-Open No. 54-31217 is known.

In such a device, an operator selects two modes, a copy mode and a facsimile mode, as needed, by a mode select switch to realize two functions.

[Problems to be Solved by the Invention] However, since the above-mentioned conventional apparatus does not sufficiently consider the operability by the operator at the time of copying and transmitting, for example, the copy mode is selected when copying a document. Since the copying operation has to be started later, there is a drawback in that quick image formation cannot be performed.

Therefore, the present invention improves the operability by the operator and realizes a quick image formation when the image processing for image formation by the image forming means and the image processing for image transmission / reception are realized by a single device. It is an object of the present invention to provide an image processing device capable of

[Means and Actions for Solving the Problems] In order to solve the above problems, the image processing apparatus of the present invention has an input means for inputting uncompressed image data (corresponding to the terminal of FIG. 9 in the embodiment). And compression means for compressing the image data input by the input means (also RL counter 151, MH encoder 1
52), receiving means (also DEMOD 157) for receiving compressed image data transmitted from the outside, and image data compressed by the compressing means or compressed image data received by the receiving means. A common storage unit (also a memory 154), a first output unit (also a MOD 156) for outputting the compressed image data stored in the storage unit, and a compressed image data stored in the storage unit. Decompressing means (also MH decoder 163 and RL counter 164) for decompressing, and a second output means (also the same) for outputting the image data to an image forming means for forming an image on a recording medium in accordance with the given image data. A line memory 141), input by the input means, compressed by the compression means, and stored by the storage means. A first output mode in which the stored image data is output from the first output unit, and an image formation by the image forming unit without the image data input by the input unit being compressed by the compression unit. A second output mode of synchronizing and outputting from the second output means, and image data received by the receiving means, stored in the storage means, and expanded by the expanding means, in the second output means. Has a third output mode for outputting from, and usually the second output mode is selected,
The change from the second output mode to the first output mode is manually performed by a predetermined operation means, and the change from the first or second output mode to the third output mode is performed by It is characterized in that it is automatically performed by receiving the image data by the receiving means.

[Embodiment] FIG. 1 is an example of an image processing system to which the present invention can be applied, which is a color system capable of reproducing a color image by reading a color document. The original 1 is placed on the transparent plate 2 of the original table and fixed by the original mat 3. The photosensitive drum 24 and the transfer drum 53 rotate in the arrow direction to execute the color process. Reference numeral 12 is a dichroic mirror for spectroscopy, and 14, 16 and 18 are CCDs that sense the spectrum and generate color signals B, G and R, respectively. The lamp 8 and the mirrors 9 and 10 reciprocate to scan the original 1 and simultaneously output color signals B, G and R from each CCD to generate a reproduction Y signal, and then reciprocate again to output an M signal. , The above scanning is repeated 4 times to sequentially form Y, M, C and BK signals,
The laser is controlled by these signals to sequentially form each color latent image on the drum 24. Each color latent image is developed by the developing devices 36 to 3
9, the developed image is transferred onto the paper on the transfer drum 53, and the drum 53 is rotated four times and repeatedly transferred onto the paper on which the full-color copy having halftones and intermediate colors is obtained.

The optical system emits light from the illumination lamps 5 and 6, and combines the light from the reflecting mirrors 7 and 8 to illuminate the original, and the reflected light is reflected by the moving reflecting mirrors 9 and 10, and the lens 11
Pass through the 12 dichro filters. Here, it is split into light of blue wavelength, light of green wavelength, and light of red wavelength.
The decomposed light of the blue wavelength of each decomposed light passes through the blue filter 13 and is received by the solid-state image sensor 14. Similarly, light having a green wavelength passes through the green filter 15 and is received by the solid-state image sensor 16. The light of the red wavelength passes through the red filter 17 and is received by the solid-state image sensor 18. That is, the original 3 is moved along the optical path by the moving reflection mirror 9 that moves integrally with the illumination lamps 5 and 6 and the moving reflection mirror 10 that moves in the same direction at a moving speed of 1/2 of this moving reflection mirror 9. The image light scanned while maintaining the length, further passed through the lens 11 and the dichro filter 12, and subjected to scanning and color separation is imaged on the solid-state image pickup elements 14, 18 and 16 of each color. The output of each solid-state image sensor 14, 16, 18 is
Signal processing is performed through an image processing unit 27, which will be described later, and the signal is output from the semiconductor laser 21 to the polygon mirror 22 as a light output to illuminate the photoconductor. Since the polygon mirror 22 is rotated by the scanner motor 23, the laser light is scanned perpendicularly to the rotation direction of the photosensitive drum 24. Further, there is a photo sensor 64 at a position 11 mm before the laser beam starts scanning on the drum, and when the laser beam hits the photo sensor 64, a BD (beam detection) signal is generated. BD determines the writing timing of one line by the laser,
The output timing for one line of the image data in the line memory is determined.

The photosensitive drum 24 is negatively charged by the negative charging device 25 which is supplied with a negative high voltage current from the high voltage power supply 25. Then, when it reaches the exposure unit 26, the transparent plate 2 of the document table
The upper original 1 is illuminated by the illumination lamps 5 and 6, reaches the dichro filter 12 via the movable reflecting mirrors 9 and 10 and the lens 11, is decomposed by the blue filter 13, the green filter 15, and the red filter 17 and is solid. An image is formed on the image pickup device (CCD) 14, 16, 18. The image output from these CCDs passes through the shading unit 104 for each color by the image processing circuit of FIG.
The gradation is corrected by the correction unit 105, the color processing is performed by the masking processing unit 109 and the UCR processing unit 119, the dither processing unit 124, and the multi-value conversion processing unit 125.
Then, a halftone reproduction process is performed and the laser beam is output from the laser driver unit 126 to the laser 21, and the laser beam is imaged on the photosensitive drum 24. There, an electrostatic latent image is formed and enters the four-color developing devices 36, 37, 38, 39 for development. Here, the three colors are separated by one exposure scan, and the above respective processes are performed, but the output of the UCR corresponding to each of B, G, R, and BK is sequentially selected for each scan of B, G, R, and black BK. . The one-color separation optical signal in the image processing unit 27 is selected by the timing signal (E signal to each gate corresponding to each UCR output) from the main body control unit 69. Then, the developing device corresponding to that is selected. The developing device selected there is performed by powder development using a magnetic blade method, and the electrostatic latent image is visualized. After that, the ghost miniature lamp 40 for erasing the electrostatic latent image and the negative post electrode 41 supplied from the negative voltage power source 25 negatively charge the electrostatic latent image.

Next, the upper and lower cassettes 43, 4 selected from the operation unit 45.
The copy paper 48 sent by the rotation of the paper feed rollers 46 and 47 from one cassette of No. 4 is placed on the first registration roller,
It passes through the lower portions 49 and 50, is passed from the conveyance roller 51 to the second registration roller 52, and is wound around the transfer drum 53. Therefore, the toner on the thermal drum 24 is transferred to the transfer electrode 54.
Is transferred to the copy paper 48 by means of. After the transfer is completed, the copying paper 48 is discharged by the high-voltage generator 25 and the discharging electrode 55 supplied with a high voltage.

In this way, the printing operation is started almost at the same time as the document scan, and the printing time is short.

In the case of a normal color original, the above operation is repeated four times for four colors and the transfer drum is rotated four times to superimpose each color. In the case of a manuscript having only one black color, when it is detected that the manuscript has only one black color at the time when one optical movement is completed as described later, G. The processes of scanning of R, development, transfer, etc. are jumped, and the black image subject operation is started. That is, the operation time for four colors is required for a color original, but the operation time for two colors or one color can be shortened for an original with one black color.

The copy paper, which has been transferred twice or four times, is peeled from the gripper 57, adsorbed on the belt 59 by the transport fan 58, guided to the fixing portion 60, fixed, and then sent out of the apparatus.

FIGS. 2-1 to 2-3 and FIGS. 3-1 and 3-2 show image processing circuit diagrams.

The parts common to them will be described below. The light of the original separated into three colors by the dichro filter 12 is the CCD 14, 1.
When 6 and 18 are irradiated, the output is amplified by the CCD substrates 101, 102 and 103 for each color and A / D converted, and 8 bits are sent in parallel as one pixel data to the next shading unit 104. When the amount of incident light on the CCD is the same (when it is white), the correction is made so that the output data for each bit of the CCD becomes equal and that the variations in the CCDs 14, 16 and 18 for the three colors are eliminated. The unit 104. This is the configuration of RAM and arithmetic unit,
The previous 8 bit data is the RAM address,
The RAM is accessed with the data, and an appropriate output is made from the arithmetic unit.

Next, the γ correction unit 105 is for linearizing the gradation characteristics between input and output, and it is possible to select the optimum γ curve for each color by switching the ROM pattern by the switches 106, 107 and 108. ing. Incidentally, the reason why the data of the upper 6 bits of the 8 bit data is processed to be the output data is that the processing in the significant level area is sufficient.

Next, the masking processing unit 109 performs arithmetic processing on each B, G, R signal at the same time to change the mixing ratio of each color component to perform color correction. As a result, the signal can be corrected according to the color tone of the developing toner. This calculation is performed by the coefficient multiplication ROM and the addition / subtraction ROM. The mixing ratio of each color is performed by switching the values (coefficients) of the switches 110 to 118. Incidentally, the reason that the calculated value is set to the upper 4 bits is that it is limited to a significant area level. Each ROM is addressed by the input data and outputs the data of the operation result. Each ROM outputs simultaneously for each color.

Next, in the UCR processing unit 119, each comparator
The COMP logically compares each color signal, and the minimum value signal of B, G, R is discriminated by the logic by each gate MiN. That
A value obtained by multiplying the minimum signal output from MiN by an arbitrary coefficient according to the value of the switch 120 is used as a black level signal. This is UC
The value that becomes the output of R BK is subtracted from each color signal in each UCR circuit. This allows black to be treated separately, and B,
Black signals can be removed from G and R, and color reproduction without turbidity is possible. The signal is selected by the gate circuit in response to select signals 121, 122, 123 from the control unit 69 in synchronism with the color output timing, and one color signal is sent to the dither processing unit 124. Then, each color signal is sequentially sent to 124 for each document scan.

In the dither processing unit 124, the dither ROM is accessed so that each color signal refers to a table by a deep signal, for example, a 1-pixel 6-bit signal, and the input signal is converted into a binary signal of 1 pixel 0 or 1. Alternatively, as shown in FIG. 3, the data of the dither ROMs 135 to 137 storing the data of the 4 × 4 matrix dither pattern and the input data are compared for each pixel by the comparators 138 to 140, and each pixel is one bit. 1 is converted into a digital signal of 1 or 0 to express halftone with 4 × 4 pixels. This makes it easy to modulate the laser. Note the pattern of the dither ROM135~137 can select arbitrarily by 91 _to 93 ₃ as 3-1 Figure. Further, as shown in FIG. 3-2, the dither processing can be omitted by the selector.

Next, this signal is stored in the read-write line memory for pixels of one document line, that is, one print line, and is output in synchronization with DB. After that, multi-value processing is performed by the multi-value processing unit 125, and the laser 21 is driven by the laser driver unit 126. The dither processing unit has a ROM ₁ in which low threshold levels are arranged, a ROM _{3 in} a high arrangement, and a ROM ₂ in the middle. The input signal is compared with these ROM outputs at the same time, and the output from each comparator is compared. Line memory 141
Put it in and latch, and divide 1 pixel into 3 equal parts. That is ROM
1 pixel data output by 1 to 3 are respectively φ ₁ to φ ₃ (8th
A pulse having a different width shown in the figure) is used for division in the AND gate 142, and each of them is output corresponding to the ROMs ₁ to ₃ , and the OR gate 143 outputs one pixel data having a different width. As a result, the beam can be pulse width modulated in four ways with a quaternary output to represent one pixel. As a result, one pixel can represent a halftone. The processes of FIGS. 2 and 3 are performed in real time (real time) substantially at the same time as the input of X, Y and Z. In other words, printing can be started almost at the same time as the document scan, and it takes less time for color printing. By the way, the halftone reproduction by the binarized dither can reproduce 16 gradations in the case of a 4 × 4 matrix. Therefore, since there are four gradations of halftones by pulse width modulation, a total of 64 gradations can be reproduced.

On the other hand, a part of the output of each UCR ROM corresponding to B, G, R is input to the black signal determination circuit 127-1 of FIG. 2-2. Note that 127-1 is designated as 127-2 through u, v, w in FIG. 2-1. The upper 4 BiTs out of the 6 BiTs are input here. This is because the color signal with little color density is ignored, and 6 BiT may be left as it is.

In the memory 128-1, θ is stored at θθθ, and F is stored at all other addresses. Therefore, if there is no color signal in the UCR signal input to 127-1, θ is output, and if there is, F is output, the latch circuit 129-1 latches this, and the hold circuit 130-1 synchronizes with the clock. input. This output S ₀
Is determined by a program by the CPU of the control unit 69 to contribute to sequence control. This will be described with reference to the flow chart of FIG.

This flow is programmed in the microcomputer of the control unit CPU (FIG. 69). First, the RESET signal Sr is output immediately before the optical scan for scanning the original, and the output Q ₁ to Q _{1 of the} hold circuit 130-1. Reset Q ₄ (step 1).

If there is a color signal even once until the completion of the first optical scanning, the hold circuit 130-1 outputs FF, and as a result, the output S ₀ of the OR gate 131 'becomes H level.

The control circuit CPU checks (4) this signal immediately after the completion of the optical scanning (3), and if it is an H level signal, performs a normal full-color copying operation (routine 5). Gate 131 is L
If the level remains as it is, it is judged that the manuscript is black, and B, G, R
The sequence selection signal is output so that the process is completed and the process is completed only by the black copying operation (6). Therefore, a sequence controller (not shown) makes only the black developing device movable to form and develop a latent image. When the transfer drum rotates once, the gripper 57 is released and the transfer paper is ejected.

In this case, when the scanning and developing processes are performed in the order of B, G, R, and black BK, the process rotation for G and R is omitted, so that the processing time for two colors is sufficient.

In addition, the manuscript is subjected to a preliminary spare scan. The color can be judged at the end of the process, so the development time for one black color is enough.

If the process is performed in the order of black, B, G, and R, the black latent image is already formed at the time of color determination (at the end of scanning), so by blocking the subsequent processing,
Processing time for one color is enough.

Even if it is determined that the input signal is a monochromatic image of B, G, R, Y, M, or C other than black, sequence processing and signal processing can be omitted in the same manner. This determination can be made by independently monitoring the outputs B, G, and R of the UCR and detecting that there is almost no output for any of the colors (described later).

Numeral 127-2 in FIG. 2-1 is for monochromatic judgment, and a part of the output of the ROM of each UCR of B, G, R is a monochromatic signal judgment circuit 127.
-2 is input. The upper 4 BiTs out of the 6 BiTs are input here. This is because the color signal with little density is ignored, and 6 BiT may be left as it is.

The OR gate 128-2 outputs L if there is no color signal in the UCR signal input to 127-2, outputs H if there is, and latches this with the latch circuit 129-2 and holds it in synchronization with the clock. Enter in 130-2. This output is sent to the control unit CPU
It makes a soft decision and contributes to sequence control. Fourth-
This will be described using the flow chart shown in FIG.

This flow is programmed in the microcomputer of the control unit CPU (FIG. 69 in FIG. 1). First, the RESET signal is output immediately before the optical scan for scanning the original, and the hold circuit is output.
Reset outputs Q ₁ -Q ₄ of 130-2 (step 100
). Then, an optical preliminary scan is performed to expose the original (step 101).

The optical prescan is completed (step 102), and if there is any color signal until then, the hold circuit 130-2 outputs the H signal to the output terminal corresponding to the color signal. For example Q ₁ is when B color original is H, Q ₂ ~Q ₄ becomes L.

The control circuit (Fig. 1 69) checks this signal immediately before the start of the optical scan for reproducing each color (step 103).
), If the signal is H, reproduction processing for that color is performed (step 104). For example, when the original is blue B, it is green G,
A sequence selection signal is output so that the reproduction processing of the red R and black is omitted and only the B reproduction processing is performed. Therefore, the sequence controller (not shown) makes only the blue developing device movable to form a blue latent image, develops the latent image, transfers the blue image to the transfer paper on the transfer drum, and completes one rotation for that. Then, the gripper 57 is released and the transfer paper is ejected.

In this case, the process rotation for G, R, and black can be omitted when scanning and developing are performed in the order of B, G, and R, and the processing time for one color is required.

In this case, the main scan may be performed at steps 101 and 102. When the blue monochromatic image is found at the end of the scan, the formation of the blue latent image is completed. Processing time.

In the case of only two colors, for example, in the case of only B and G originals, the reproduction processing of the red R and black is similarly omitted.

Since in the case of full-color becomes a Q ₁ ~Q ₄ are all H step
All 104 to 107 will be executed.

In the case of the type in which each color is reproduced on four photosensitive drums and the resist is sequentially transferred onto one sheet of paper, the paper feeding speed can be increased and the time can be shortened after finishing the process of the specific color.

The present invention is effective even if the input signals B, G and R in FIG. 2 are from the host computer, and X, Y and Z are also effective.
It is possible to switch between the host and the CCD reader at the connection point of if necessary. In this case, if a monochrome command signal or a monochromatic command signal is added to the head of the transmission signal from the host, it can be judged to be a black image or monochromatic.
Further, even in the case of a 1-pixel 4-dot type printer, it is effective in shortening the time when there is a difference between the monochrome process, the single color process and the full color process. Further, since the full color signal processing step can be omitted, the image quality of black or other single color can be reproduced well.

When a monochromatic image (one color for each of B, G, R, black, etc.) is judged, it can be recognized as a character image and the dither unit can be output in an output state without impairing the resolution. In this case, in FIG. 3-1, in order to reproduce a slight halftone by utilizing the pulse width modulation of the laser drive signal according to the above-mentioned four values, a static threshold value (3 levels) is applied _to the signals a to the descrambler ROMs ₁ to ₃ . _The above pulse width modulation or brightness modulation can be performed by setting _{1 to} a ₃ .

Further, by judging the output from the hold circuit 130 for each line and applying the reset, it is possible to perform the monochromatic judgment for each line and to selectively control signal processing such as successive dither. Further, it is possible to make a determination for every several pixels, so that the synchronization can be accurately performed and the partial selection control described above can be performed.

As described above, by determining a specific color such as black in a color system such as a color copying machine, it is possible to reduce the copying time from about 1/2 to 1/4 for a black original document. Further, it is possible to perform signal processing that enhances the resolution of characters and the like. Since unnecessary color signal processing is not performed, the quality of the specific color does not deteriorate.

In addition, useless charging, laser irradiation, development,
Since the transfer and cleaning processes are prohibited, the life of the machine can be extended without giving unnecessary fatigue.

Further, the image quality is not impaired because the color determination is performed and the image processing is selectively controlled. The black judgment is made based on whether or not the output after each color UCR process is at the peak level, or the input B, G, R signals (γ
Maximum value of converted signal) or Y, M, after masking correction
It is determined by whether or not the minimum value of the C, (B, G, R) signals exceeds a predetermined level. Further, it is possible to consider the line image by the black judgment and omit the dither processing so as not to impair the resolution. Incidentally, it is also possible to further judge whether the black is a line drawing or gradation with the black judgment, and in the latter case, the dither processing can be performed with a matrix pattern different from the color.

Next, the determination of the halftone and the control of the halftone processing by the determination will be described with reference to FIGS. 2-3 and 3-2.

Other signals branched after the masking process are halftone judgment circuit 12
It is sent to 7-3. In each of the memories 128-3, 128-4, and 128-5, θ is from θθ to θF, and 2 is from 1θ.
1 is preliminarily stored in the E address, and θ is preliminarily stored in the 2F to 3F addresses. This is because when 1 out of 6 bits of the data to 127 is set to a middle level, 1 is output to indicate that a halftone exists. Therefore, a memory that can be accessed in 6 bits is provided, and the addresses that can be accessed in 6 bits are 64 from θθ to 3F.
By addressing this memory with 6-bit data, the data level is divided into upper, middle and lower levels, and it is determined whether or not there is a halftone for each color. There are 64 6BiT signals input to the memory B128-3 from θθ when there is a lot of light (the density of the original is low) to 3F when there is little light (the density of the original is high) due to the intensity of the light input to the CCD. Changes to.

As an example, the input data to 127 is low density when the signal is θθ to θF, intermediate density when the signal is 1θ to 2E, and high density signal when the signal is 2F to 3F. For example, when the intermediate density signal is input to the memory B, 1 is output, and otherwise, θ is output. This is latched by the latch circuit 129-3 and input to the hold circuit 130-3 in synchronization with the pixel clock. This hold circuit holds data until a reset signal is input. Therefore, when data between 1θ and 2E exists, the OR gate 131 outputs 1 (H). When this is judged by the microcomputer of the control circuit 69, the dither processing shown in FIG. 3-2 is performed. However, if 1 (H) is not output, it is judged that the dither processing is omitted and the dither processing is performed at a fixed threshold level. Quantify.

This operation will be described with reference to the flow chart of FIG. This flow is based on the ROM of the microcomputer of the control unit 69.
Is programmed to. RES just before optical scan
Outputs ET signal Sr (step 200), keep resetting the output Q ₁ to Q ₃ of the hold circuit. The operation of the mirror system is started to start the first optical scan. If there is an intermediate density signal even once during the scan, the hold circuit 130-
3 latches 1 and outputs it, resulting in OR gate
The output S ₁ of 131-3 becomes “H”. Control circuit 69 (first
When the optical scanning completion is judged (step 202), this signal is checked immediately after that (step 203).
), If the signal is "H", the control circuit 69 causes the switching signal Sl =
0 is output to the selector, and selectors 141 to 143 are used for the dither RO.
Switching to the M135-137 side (step 204), dither processing is performed. If switches the selector 141 to 143 outputs Sl = 1 if S ₁ is "L" signal to the generator side of the fixed data 1F (step 205), to Omitsuto the dither processing.

Therefore, the character image without halftone is not dithered so that the resolution is not impaired. Also, if halftone is judged for all color components and even one component has halftone,
The quality of color reproduction is good because it is dithered.

As the first optical scan, not the scan directly related to the reproduction image formation, but the previous scan at high speed (no reproduction image formation) is performed to control the selector in advance to perform the dither and fixed value selection control. You can also

In addition, the range determined as the intermediate density is 1θ to 2E of the memory 128.
It is also possible to freely determine not only the portion corresponding to, but also the memory of the table in which the storage pattern of 1 and θ is changed between θθ and 3F.

A circuit as shown in FIG. 5 can be added or replaced with x, y, z in FIGS. 2-3. This is because the BD signal from the beam detector 64 in FIG. 1 (a signal obtained by detecting the end of the beam scanning of one line) is input to the counter 145, and if an appropriate count value (for example, 4 × 4 dither matrix) At 4, the RESET signal is output to the hold circuit 130. In that case, by directly inputting the signal S ₂ of the OR gate 131 to 144 as the switching signal Sl of FIG. 3, it is possible to perform successive dither processing if there is an intermediate density portion for every four lines.
Therefore, the dither threshold value and the fixed threshold value can be selectively controlled for each region of every four lines. In this case, a buffer capable of storing four lines of the gate output data shown in FIG. 2 is provided, and the output of this buffer is input to the dither circuit so as to be binarized by a dither or a fixed threshold value. This makes it possible to distinguish between halftone areas and character areas while performing printing while actually printing documents. Further, in order to perform the dither processing of other lines at a high speed while performing the halftone judgment, two 4-line buffers can be provided in parallel and alternately used for judgment and processing.

With such a simple circuit, it is possible to obtain a high resolution print by performing a high gradation print on a document or a part thereof having an intermediate density and without performing a dither process on a document having no intermediate density. .

Even if the B, G, and R input signals in FIG. 2 are from the host computer, one of the present inventions is effective, and the X, Y, and Z connection points can be connected to the host if necessary. The CCD reader can be switched. In this case, if the command signal without the halftone is added to the head of the transmission signal from the host, it is possible to control the selectors 132 to 134 so as to judge the command signal and omit the dither processing. 1 pixel 4
This example can be applied to bit type printers, thermal printers, and ink jet printers.

In this example, when the dither processing is omitted, the pulse width modulation of the laser drive signal is performed according to the above-mentioned four values, so that a slight halftone can be reproduced and a low-level halftone (there may be a dither-omit at the end). Can be reproduced. In addition, it is possible to make a halftone judgment for every several pixels, to make synchronization accurate, and to perform the partial selection control described above.

FIG. 6 is a circuit diagram for inserting characters, numbers and the like into the above color image.

200 is a code generating means for generating characters and numerical values as code data (for example, ASCII code), M ₁ is a buffer memory for storing the code data at the same time as the code is generated, A
DC ₁ is an address counter for controlling addresses for writing and reading the memory, CG is a well-known charactor generator for outputting characters and numerical values as dot pattern image data according to the code data read from the memory M ₁ .
M ₂ is a buffer memory that stores the dot data from the CG at the same time as it is output.
Dots are stored so as to correspond to each other, that is, a dot pattern (bit pattern) for a plurality of characters and numbers represented by 0 and 1 is a set of each character and each numerical value, and a predetermined pattern similar to the bit serial data of the reproduced image is stored. Stored at intervals. The ADC ₂ is an address counter that controls the address for writing and reading the memory M ₂ , and this determines the read start timing in synchronism with the progress of color image data processing. The character composition position of can be determined. 201 is a signal input source for presetting the timing. When the image processing shown in FIG. 2 reaches the preset coordinates X, Y by 201, the reading from the memory M ₂ is started, and the color reproduction corresponding to the above position after the dither processing is performed. The characters are output in synchronization with the output, and they are combined.

205 indicates when the output of the comparator 206 is “L” (white, halftone),
Gate that outputs CG dot output as "H" (black), 20
Reference numeral 4 is an inverter that outputs L (white) when the output of the comparator is "H" (black). The comparator 206 outputs "H" when the black component output A in FIG. 2 is above a certain level L ₁ and outputs "L" below. Therefore, when the image is a dark background color, the character image from the CG is output as a charactor image signal B in order to make the character image from the background color white, and to make the character image black when the tone is light. . This signal B is input to the OR gate 210 shown in FIG. 3-2 and overlapped with the image data after dither processing to be combined. In this case, since the inserted characters are not dithered, the resolution is not impaired.

The R / W signal is a write / read signal, and the read signal from the memory M ₂ is a black / white signal in synchronization with the black processing step.
It is applied to the black process and it is output to form black as characters. If the color image is a blue monochromatic image and if it is desired to insert characters by red, the read signal is synchronized with the red processing so that the red processing signal is output and the B signal is output only during that processing. Give to ₂ .

The address counter ADC ₂ counts the number of image data processing dots (CLK) and the number of lines in order to determine the timing at which the reading of the memory M ₂ is started.
When the preset X, Y by 1 is reached, the clock CLK
The reading of the memory M ₂ is started in synchronization with. The counting of dots (pixels) starts counting the bit (= CLK) for each line end signal. The line counting is started every time the color data processing is started by the beam detection signal BD in the laser scanner indicating the end of one line scanning or the end signal counting the bits for one line. Note that the processing in FIGS. 5 and 6 is also performed in real time (real time).
In other words, while performing the document scan and the printing at approximately the same time, it is possible to understand the character and synthesize the character.

As shown in FIG. 7, when the code "1984" is stored in the memory M ₁ by the key or transmission line attached to the copying machine of FIG. ₁ , the CG converts it into a dot pattern and stores it in the memory M ₂ . To do. After that, the above-mentioned color data processing becomes possible (in this example, scanning of the original by the optical system becomes possible. Unless there is a command input indicating that there is no inserted data,
Until then, manuscript scans are prohibited. ) The color data processing is started, and the number of dots and the number of lines are changed in the process of Brasksky (4th equipment scan).
When the preset coordinates X, Y of 201 are reached, the reading of the memory M ₂ is started, the B signal of the character is sequentially output in synchronization with CLK, and is input to the gate 210 of FIG. 3-2. The latent image of the black character is formed on the drum by being combined with the data before the value processing, and is transferred and combined with the previous color image to obtain a color print containing the character. If necessary, other color characters such as red and blue can be inserted as described above.

However, as shown in FIG. 7, when a character is added to a position where a part of a dark color (black) is used as a background, the background is automatically judged from the signal A and a white character signal is formed as described above. And outputs as signal B. This measure is based on a circuit configuration in which the synchronization relationship is accurate so that the color image processing can be achieved in real time. The preset data 201 can be the key of the copying machine shown in FIG. 1 or the transmitted code data.
As the memory 200, a memory ROM storing a format having a character or a mesh may be used.

By the way, when the background color is repeated in a short range such as a stripe pattern, it may be unsightly to process the white color accordingly. To eliminate the inconvenience, a delay circuit is provided at point W in FIG. The whitening can be performed only when the base of the predetermined range is dark.

By the way, in the case of adding all the characters with a white outline, it is necessary to determine the read timing of the memory M ₂ for each color so that the treatment can be performed in each color image processing step of the four colors.

FIG. 9 shows that the composite image data after the binarization processing is transmitted to another printer without being multivalued.

In the figure, selector 132, dither ROM 135, comparator 13
8, OR gate 210, latch, line memory 141 is the third
It is the same as Fig. 2. However, the dither ROM 135 is the third
-Dither pattern is different from that of Fig.-2. It is selected by the signal a. a is generated by a data transmission command from the key input unit in FIG. The dither pattern determined by a is not a pattern dedicated to multi-value quantization but a pattern dedicated to binarization, and is a pattern that allows halftone reproduction without the processing by the dither ROM B6, 137.

Therefore, by transmitting only the composite data of the output of the comparator 138 and the character signal B, the halftone color composite image can be transmitted and reproduced sufficiently.

FIG. 9 is a diagram in which a transmission circuit is added for the line memory 141 for storing the data having a high density level by setting the dither ROM 135 as described above in FIG. 3-2.

Reference numeral 150 denotes a switch for switching data transmission for printing and transmission, which is switched in the dotted line direction by the transmission command signal a. 151 is the number of times "1" in the image data continues,
A run-length counter that counts the number of times "0" continues, 152 is an MH encoder that encodes image data according to the count data of the counter 151, and 151 and 152 are well-known ones that compress the bit amount of the image data to be small. is there. Reference numeral 153 is the document scan yan 151 in FIG.
The switch, which is sequentially switched in synchronization with the end of encoding by 152, is controlled by a signal b upon completion of encoding of image data of each color component. Reference numeral 154 denotes a memory for storing each color component data coded corresponding to the switch 153 or each color component data transmitted, and B, G, R, BK each having a storage amount of one document page. 4 memory parts. Reference numeral 155 is a switch for switching whether the data of the memory 154 is sent to the transmission unit MOD or the printing unit, and is switched to the dotted line by the signal b by the data reception.
The MOD 156 is a well-known high frequency modulator for transmitting data to a distant place. The DEMOD 157 is a well-known high frequency demodulator that extracts data from the transmitted high frequency. 158 is a separator that determines the type of data that has been sent, outputs it to line MH if it is an MH code, and outputs it to line AS if it is an ASCII code (hexadecimal code). Further, even with the MH code, it is discriminated whether or not it is the color B, G, R, and BK components, and output to the corresponding lines. Since this separator has command data indicating the type of data at the beginning of the transmitted data, the separator is used to select the output line. The ASCII code is character data such as characters, and is character data when a halftone image and a character image are serially sent at different times. As for the MH code, when the code corresponding to B has been sent, the code corresponding to G is sent, and the data of each color component is sent serially. Each MH data is stored in the memory 154. Numerals 159 to 161 are charactor image generators similar to M ₁ , CG and M _{2 in} FIG. 7, and output bit-wise charactor image data C from the charactor code by the charactor generator. The character data C is synthesized by the OR gate 162 with the transmitted halftone data in synchronization with each other as shown in FIG.
Reference numerals 163 and 164 are known MH decoders and run length counters for converting the sent MH code data into bit image data. Reference numeral 163 is a selector for determining whether the data to be sent to the printing unit is the decoded data or the data by the document scan.
To switch to the received data.

To explain the operation, in the transmission mode, the color processing signal corresponding to the first in-scan blue of the document is binarized by the dither circuit 124 to be converted into one-pixel / one-bit data. The combined data of this data and the charactor data is sent to the MH coding circuit composed of the counter 151 and the decoder 152 via the switch 150, and the maximum MH of 36 bits.
It is converted into a code and stored in the memory B of the memory 154 via the switch 153. Then, the high frequency is modulated by the modulator 156 by the data of the memory B and transmitted. When the transmission of the composite data corresponding to blue is completed, next
Scan for the second time, perform color processing corresponding to the red, and perform binarization processing and composition processing as described above, store in memory,
To transmit.

As described above, the composite color data of the character and the scan color image is sequentially sent for each scan in the order of B, G, R and BK. In this case, since an image having no halftone such as characters in the scan image is not dithered by the selector 132 as described above, it can be transmitted while maintaining the resolution by the CCD. Further, the data in the memory 154 can be sequentially filed on an optical disk for each color, and a plurality of pages of documents can be sequentially filed.

If it is determined in FIGS. 2-1 and 2-2 that the document image is one component such as a black component, the determination signal prevents the document scan after the determination. Therefore, the composite data of the one-component data and the character data is stored in the memory 154 and transmitted.

The dither ROMs 135 to 137 have different dither patterns for each color component so as not to impair the color quality. The dither pattern is selected by a 2-bit code signal K indicating a color component, which is synchronized with the control signals B, G, R and BK to the E ports of the gates 121 to 123 in FIGS. Done by.

Next, the received signal is divided into data lines for each color component by the data separator 158 and sent, and stored in the memory corresponding to each color. This data is sent to the decoder and the counter through the switch 155, and the code data is converted into serial dot bit data. This bit data is recombined with the charactor if necessary, and the selector 163
To the line memory 141 for printing. After that, laser printing is performed in the same manner as described above. Note that the character image C to be added can also be generated by a key operation in the receiving side system as shown in FIG. When the character image C to be added is sent as an ASCII code separately from the MH image data, the code data is separated from the MH image by the separator 158 and the dot image is obtained by the character generator CG ₂ via the line AS. Is converted to. Charactors are transmitted as code, so transmission efficiency is good and time is fast. The charactor data and the charactor data in FIG. 7 include text information created by word processing by key input or the like, and management information such as date and time. The latter management information is added and printed outside the area of the document image to be printed. Therefore, the output timing of the management information is preset in the address counter AD ₂ (FIG. 7).

The received information is 1 pixel 8 which represents the halftone in 8 bits.
In the case of bit data, the separator 158 judges it by a command and sends it to the buffer 170 to input the data of the upper 6 bits to the input of FIG. 9 and input it to the dither circuit 124. Therefore, this signal is sent to each dither R as described above.
It is binarized by the OMs 135 to 137 and stored in each line memory 141 as bit-serial image data. In this case, the selector 163 is set in the direction to send the scan image data to the printing section. Further, the character data C in this case is combined via the OR gate 210. In the case of halftone data, pulse width modulation is also performed, and halftone reproduction from both digital and analog sides is performed.

The character data C is address-controlled in the memory M ₄ so that the character data C is output in synchronization with the decoding operation of each color component code data when the received image is full color.
If a character image of a specific color is desired, it is output from the memory M4 in synchronization with the decoding of the code of the specific component.

The MOD 156 is a converter that converts 8-bit parallel data into 1-bit serial data for transmission with 1 data line or lineless. The DEMOD 157 is a converter that converts the received 1-bit serial data into 8-bit parallel data. It has a converter for converting.

FIG. 10 shows that a bit signal of a character image to be synthesized is added before the halftone judgment of FIGS. This can be achieved by inserting the circuit of FIG. 9 at point P of FIGS. 2-3. This is to insert the charactor signal B (FIG. 7) into the upper 2 bit lines (corresponding to 2F to 3F) having the highest density of 6 bits of the image signal from the masking circuit. As described above, the halftone judging circuit 127-3 judges whether or not the data 1 is present in 1θ to 2E of the middle and middle bits of the 6 bits. Therefore, the charactor signals inserted in 2F to 3F are not considered to be halftone, and therefore the selectors 132 to 134 are switched to be binarized not at the dither pattern level but at the threshold level fixed for each pixel.
Therefore, this character signal is not dithered. That is, the bit charactor signal B is applied to the data lines of the upper two bits via the OR gates 301 and 302 in FIG. 3, so that a high level character can be inserted, and this character is not subjected to dither intermediate processing so that the resolution is not impaired. Each of the latches shown in FIGS. 2-1 and 2-3 adds a data delay of about 1 bit for synchronizing the image processing, and B, G, and R next to the P point are also a few bits. This is a latch circuit that applies a delay of about one line.

FIG. 11 shows a bit signal of a charactor image added after the multi-value quantization process of FIG. 3-2. No. 3-2
This can be achieved by inserting the circuit of FIG. 10 at point Q in the figure. This gives bit data B of the character image to the multi-valued output, that is, pixel data (dot data) pulse width modulated by the pulses φ _{1 to} φ _{3 in} FIG. At this time, when the B signal is combined with the image signal in synchronization with φ ₁ , dark characters are added. That is, when the switch 310 in the figure is turned on, a pulse having a basic width is outputted from the AND gate 303 for φ ₁ , B and 310, and this pulse is added to the image signal line via the gates 306 and 307. Switch 308
When is turned on, the character signal B is added to the image signal line in synchronization with φ ₃ of the 1/3 pulse of φ ₁ . Therefore
It becomes a pixel with a width of 1/3 and a character with a density of 1/3 is added. In this way, the density of the inserted character can be selected by selecting the switches 308 to 310. With this method, the pulse width in one pixel is changed, so the resolution of the charactor image is not impaired. Further, as described above, since character data can be added in synchronization with the black component or in synchronization with each color component, it is possible to insert a black character or a single color character such as blue and control the density of the character.

In each of the above examples, a part of the scan image can be canceled, and the character image can be inserted in the cancel portion. This can be achieved by providing a data selector instead of each OR gate 210 and corresponding to the combining portion, and controlling the time of the selector in synchronization with the address counter. In this case, if the scan image is full-color, the cancel cell part is white, and black or monochromatic characters can be formed therein.

In one of the examples, as shown in FIG. 2-3, halftone judgment and character composition can be performed before the completion of the document scan, and printing can be started before the completion of the scan. Therefore, the reproduction time of the composite image can be shortened. . It is especially convenient for color image reproduction. In addition, real-time color processing requires less memory.

[Effect] As described above, according to the present invention, the operability of the operator is improved when the image processing for image formation by the image forming unit and the image processing for image transmission / reception are realized by a single device. Further, it is possible to provide an image processing apparatus capable of quick image formation.

[Brief description of drawings]

FIG. 1 is a sectional view of a color copying machine to which the present invention is applicable, FIGS. 2-1 to 2-3, 3-1 and 3-2, FIG. 5 and FIG.
FIG. 4 is a circuit diagram of the image processing unit, FIGS. 4-1 to 4-3 are flow charts for black judgment, single color judgment, halftone judgment and processing by the judgment, and FIG. , 8th
FIG. 9 is a pulse waveform diagram for pulse width modulation of a laser beam, and FIGS. 9 to 11 are other image processing circuit diagrams. In the figure, 101 to 103 are CCD substrates, 104 is a shading correction circuit, 105 is a γ correction circuit, 109 is a masking circuit, and 119.
Is a background color removal circuit, 127-1 and 127-2 are monochromatic detection circuits, and 127-3 is a halftone detection circuit.

Claims (1)

[Claims] 1. Input means for inputting uncompressed image data, compression means for compressing the image data input by the input means, and receiving means for receiving the compressed image data transmitted from the outside. A common storage unit that stores the image data compressed by the compression unit or the compressed image data received by the reception unit; and a first storage unit that outputs the compressed image data stored in the storage unit. Outputting the image data to an output unit, a decompressing unit that decompresses the compressed image data stored in the storage unit, and an image forming unit that forms an image on a recording medium according to the given image data. Second output means, image data input by the input means, compressed by the compression means, and stored in the storage means is output as the first output. A first output mode for outputting from the means, and without synchronizing the image data input by the input means with the compression means, in synchronization with the image formation by the image forming means, and from the second output means. A second output mode for outputting, and a third output mode for outputting from the second output means image data received by the receiving means, stored by the storage means, and expanded by the expanding means. Further, normally, the second output mode is selected,
The change from the second output mode to the first output mode is manually performed by a predetermined operation means, and the change from the first or second output mode to the third output mode is performed by An image processing apparatus, which is automatically performed by receiving image data by a receiving unit.