JPH03183264A - Picture processor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an image processing apparatus that can obtain a simple reproduced line image of an original image having complex density change areas.

[Conventional technology]

As a digital copying machine that processes the original image to obtain a line image, various types of image processing such as dither processing, gamma correction, undercolor removal, etc. This is for duplicating reproduced images.
This function is not intended to create a reproduced image by converting a complex original image into a simple form, so if the user wants to process the reproduced image by adding annotations or markings, the -layer There was a problem in that it became cluttered and extremely difficult to see.

[Problem to be solved by the invention]

This invention was made by focusing on the above-mentioned problems of the conventional example, and reproduces the changing density part of the original image as a line drawing.
It is an object of the present invention to provide a processing device of this type that allows a user to easily make additions and corrections to a reproduced image.

(Means for Solving the Problems) Therefore, in the present invention, this type of image processing apparatus is provided with a density detection means for detecting a density change part of an original image, and a density detection means for detecting a density change part of an original image, and a constant density detection means for detecting a density change part of an original image. The above object is achieved by comprising a line drawing processing means for performing line drawing processing to form a line image with density.

(Function) With the configuration of the present invention as described above, it is possible to easily obtain a simple reproduced line image rather than an original image having complicated density changes or an original image with mixed colors.

(Example) An example of the present invention will be described below with reference to Figs. 1 to 13. In the figures, the same or corresponding parts are denoted by the same reference numerals, and redundant explanation will be omitted.

(Structure) FIG. 1 is a sectional view of an embodiment of an image processing apparatus to which the present invention can be applied, in which 1 is an original, 2 is a transparent plate for placing an original M41, and 3 is a transparent plate on which the original M41 is placed. The original M41 is placed on the
4.5 is each illumination lamp, 6
．． 7 is each reflecting mirror, 8 is a main body control unit for controlling each part, and 9.10 is each movable reflecting mirror 11 that moves at different speeds (v, 1/2V) under the control of the main body control unit 8. , 12 is a lens 1 for collecting the light reflected by these movable reflecting mirrors 9 and 10, respectively.
Dichroic mirror 13 separates the light that has passed through 1 into blue wavelength light, green wavelength light, and red wavelength light; 14 is a solid-state imaging device such as a CCD for receiving the light that has passed through the blue filter 13; 15 is a green filter that similarly passes green wavelengths; The solid-state image sensor 17 for receiving light is a red filter that passes light of red wavelength.

18 is a solid-state image pickup device for receiving light from the red filter 17; 19 is a white calibration plate; 20 and 21 are cooling fans disposed in the optical system to dissipate heat from the illumination system; , an image processing unit as an image processing means to be described later; 23 is a semiconductor laser; 24 is a semiconductor laser 2;
a polygon mirror irradiated with laser light La from 3;
5 is a scanning motor for rotating the polygon mirror 24, and 26 is a scanning motor for rotating the laser beam La perpendicularly to the rotation direction.
a photosensitive (body) drum for scanning and exposing; 27;
a sensor 28 for detecting light scanning the photosensitive drum 26 and generating a beam detector (B-D) signal;
28a is a negative charger, and 29 is an exposure section.

30 to 33 are developing devices for each of the four colors B, G, R, and BK,
34 is a small ghost lamp for erasing an electrostatic latent image; 35 is a negative post electrode to which high voltage is supplied from the negative high voltage power source 28; 36 and 37 are each selected by the operation section. Cassette, 38.39 is each paper feed roller, 40
41 and 42 are upper and lower second registration rollers, respectively, and 4
3 is a conveyance roller, 44 is a second registration roller, 45 is
A transfer drum for transferring the toner on the photoreceptor of the tram 26 onto the copy paper 40, 46 a transfer electrode for transferring the toner on the photoreceptor onto the copy paper 40, and 47 cleaning the transfer tram 45. A transfer drum cleaner 48 for cleaning the transfer paper 40 is supplied with a high voltage from the high voltage power supply 28.
48 is a gripper, 50 is a conveyance fan, 51 is a conveyance belt for adsorbing and conveying the copy paper 40, 52 is a fixing section, and 53 is a static electricity remaining on the photosensitive drum 26. A pre-cleaner static eliminator 54 is a cleaner unit for removing toner on the photosensitive drum 26, and 55 is an AC pre-static eliminator for removing the potential of the photosensitive drum 26.

(Image Processing Unit) Next, a circuit block diagram of the image processing unit 22 is shown in FIG.

In the figure, 56, 57, and 58 are concentration detecting means for A/D converting the light received by each solid-state image sensor (CCD) 14, 16, and 18, and detecting a change in the concentration of the original M41. Each CCD light receiving unit 59 is connected to each of the CCs.
a shading unit 6 for calibrating the output level of the D light receiving unit 56, 57, 58 to be constant;
0 is a γ (gamma) correction unit 6 for switching the human sensitivity of the CCD in response to a signal from the main body control unit 8;
1 injects B and c into the signal from this γ correction unit 60, respectively.
:, a masking processing unit for performing R color correction,
62, the B, G, R
A UCR processing unit 63, 64, 65 for obtaining a black level signal from a signal of 63, 64, 65 is a UCR processing unit 63, 64, 65, which is connected to each buffer circuit 66, 67, 66, 64, 64, 64, 64, 64, 64, 64, 64, 63, 64, 64, 63, 64, 64, or 64, UCR processing unit 63, 64, 65, respectively, provided on the CCD CD substrate center of each of the CCD light receiving units 56, 57, 58, respectively. 68 is each CLK
Drivers 69, 70, and 71 are each of the solid-state image sensors (
Amplifiers 72, 73, and 74 are used to amplify the signals obtained from the CCDs 14, 16, and 18, respectively, and 72, 73, and 74 are amplifiers that convert analog signals from the amplifiers 69, 70, and 71 into digital signals. It is a D converter.

75, 76, and 77 are ROMs for shedding correction corresponding to B, G, and R, respectively, and 78° and 79.80 are as follows.
Each RAM as a memory connected to each ROM75, 76, 77, ROMs 81, 82, 83 for γ correction corresponding to each color of B, G, R, 84, 85, 86 for γ correction latches for holding signals, 87-
95 is a ROM for counting and multiplication; 96, 97, and 98 are ROMs for addition and subtraction; 99, 100, and 101 are for receiving signals from the masking processing unit 61 corresponding to each color of B, G, and R, respectively. Each latch 102 for holding constitutes the UCR processing unit 62 and the latch 100
, 101, each comparator 103 for comparing the B color data and the G color data is connected to the latch 99.
104 is a comparator for comparing the data of G color and R color from the latch 99.100, and 105, 106 is a comparator for comparing the data of R color from the latch 99.100. are each N07 circuit arranged on the output side of each of the comparators 102, 103, and 104, and 108, 109, and 110 are each arranged on the output side of each of the comparators 102, 103, and 104, respectively.
02, 103, 104 and each N07 circuit 105, 106,
Each AND circuit for taking an AND with 107, 111,
112, 113 are the respective AND circuits 108, 109,
The output of 110 is used as an enable signal for blue, edge, and
Each latch for holding the minimum value of the three red color signals, 11
4゜115.116 corresponds to each of the colors B, G, and R and are connected to the output sides of the latches 99, 100, and 101. 117, 118゜119.120 corresponds to the enable signal (E ), each ROM 121 for UCR correction is driven separately by the ROM 1 for UCR correction.
A latch 122 connected to the output side of 20 is a gate circuit.

(Line drawing processing circuit) In addition, FIG. 3 shows a line drawing processing circuit 12 as a line drawing processing means.
3 is shown in detail. In the figure, 124 is a latch for holding the signal from the image processing unit 22;
25, 126, 127 are shift registers, and 128 is a select signal (CS) for each input port P1 to P1.
Each data selector for selecting P3, P4 is an output port, 129 is a subtraction circuit, 130 is this subtraction circuit 12
A two-man powered EX-OR circuit 131 forming part 9 is a latch for holding the output of this subtraction circuit 129.

132 is a dither processing unit, 133, 134, 135
136, 137, 138 are respective ROMs for dither processing, 136, 137, 138 are respective comparators for comparing the data of the latch 131 of the line drawing processing circuit 123 with the data of each ROM 133, 134, 135, 139, 140, 141 are each The latches 142, 143, 144 for holding the outputs of the comparators 136, 137, 138 are connected to the R/W line memories 145 for storing the data held in the latches 139, 140, 141. 146 is the multivalue processing unit 145.
The latches 147°148.149 are each AND circuit configured on the output side of the latch 146, and 150 is
A synchronous counter 151 that gates each of these AND circuits 147, 148, 149 is connected to a synchronous counter 148 and is used to send out a BD signal as a synchronous signal.
D signal generator, 152, each of the AND circuits 147.1
Each OR circuit arranged on the output side of 48, 149, 153
154 is a pattern generator for generating a pattern signal to be sent to this blanking circuit 153;
5 is a laser driver for driving the aforementioned semiconductor laser 23 in response to a signal from the blanking circuit 153;
156 is a scanner unit for scanning the laser beam La from the semiconductor laser 23.

(Copying process) Next, the copying process will be outlined. A document 1 is placed on a transparent plate 1 and pressed with a document mat 3 from above. When the device is started, light is emitted from the illumination lamps 4 and 5, which is combined with the light from each reflecting mirror 6.
The reflected light from the document 1 is reflected by each movable reflecting mirror 9.10 and passes through the dichroic mirror 12 via the lens 11. Then, the light that has passed through the dichroic mirror 12 is split into blue light, green light, and red light, and the decomposed light having a blue wavelength among each of the decomposed lights passes through the blue filter 13 and is divided into blue light, green light, and red light. Similarly, light having a green wavelength that is received by the solid-state image sensor 14 is received by the solid-state image sensor 16 via the green filter 15, and light having a red wavelength is received by the solid-state image sensor 16 via the red filter 17. The light is received at 18.

The source 811 passes through the lens 11 and the tichroic mirror 12 while the optical path length is kept constant by a movable reflection mirror 9 that moves together with the illumination lamps 4 and 5 and another movable reflection mirror 10. images are formed on the solid-state image sensors 14, 16, and 18 of each color.

Further, a white edge plate 19 for correcting the above-mentioned amount of light when the illumination lamp 4 moves along the original Ml is disposed in front of the NMI. At this time, the cooling fans 20 and 21 radiate heat from the lighting system to maintain a specified temperature.

Further, the outputs of the respective solid-state image sensors 14 and 16° 18 are transmitted to the semiconductor laser 23 via the image processing unit 22 as an image processing means, and the semiconductor laser 23 is turned ON -OF i! The laser beam La is scanned perpendicularly to the direction of rotation of the photosensitive drum 26 because the polygon mirror 24 is rotated by the scanning motor 25.

Since the B-D sensor 27 is disposed at a position approximately before faun when the laser light La starts scanning on the photosensitive drum 26, when the laser light La is received, the B-D (3
A signal is emitted and all parts are synchronized. At this time, the photosensitive drum 26 is negatively charged by a negative charger 28a to which a high negative voltage is supplied from the high voltage power supply 28. On the other hand, since the document 1 on the transparent plate 2 is illuminated by the illumination lamp 4.5, the movable reflection mirror 9.10 and the lens 11,
Dichroic mirror 12. Blue filter 13. Green filter 15. Hara M via red filter 17
41 images are captured by each solid-state image sensor 14. is, is
imaged on top.

The image output obtained there is subjected to shading correction for each color, that is, the shading unit 59 performs shading correction, the γ correction unit 60 performs γ correction, and the masking processing unit Color correction is performed by 61 and the next stage UC
The R processing unit 62 performs undercolor adjustment, and the dither processing unit 132 and the multi-value processing unit 145 produce a signal corresponding to the shading of the original 1. This signal is sent to the laser driver 155 to drive the semiconductor laser 23 to emit laser light La, which is irradiated onto the photosensitive drum 26 via the polygon mirror 24. There, an electrostatic latent image is formed, and as the photosensitive drum 26 rotates, the electrostatic latent image enters each of the four color developing devices 30 to 33.

Here, in one exposure scan, the three-color separated light is transmitted through the line drawing processing unit (123) based on the signal from the main body control section 8! When you select a color, one corresponding developer (e.g. 3
1) is selected. Then, the selected developing device 31
Powder development is performed using a magnetic blade method, and the electrostatic latent image is visualized. Next, the electrostatic latent image on the drum 26 is charged by a ghost lamp 34 for erasing the electrostatic latent image and a post electrode 35 to which a negative high voltage from the high voltage power source 28 is applied.

Next, each of the upper and lower cassettes 36, 37 is selected by the operation section, and the copy paper 40 that has been conveyed by rotating one of the paper feed rollers 38, 39 is transferred to each of the upper and lower rollers 41, 42. Gripper 49
The toner of the image formed on the photosensitive drum 26 by being wrapped around the transfer drum 45 is transferred to the copy paper 40 by the transfer electrode 46.

This transfer is performed as many times as the selected color, and each time a high voltage is supplied from the high voltage voltage #28.
The copy paper 40 is neutralized by 1i48. After completing the transfer a selected number of times, the copy paper 40 is peeled off from the gripper 49, attracted to the conveyor belt 51 by the conveyor fan 50, and guided to the fixing section 52.

On the other hand, the potential remaining on the photosensitive drum 26 is further removed by a pre-cleaner static eliminator 53, and the toner on the photosensitive drum 26 is removed by a cleaner unit 54. Note that the potential on the photosensitive drum 26 is neutralized by a pre-ACC electric appliance 55.

(Image Signal Processing) Image signal processing in the copying process will be explained in detail below based on the circuit diagram of FIG. 2.

The light from the original 1 separated into three colors by the dichroic mirror 12 in the preceding stage of the image processing unit 22 is received by each solid-state image sensor 14, 16.18, and its information signal is amplified by each amplifier 69, 70°71. each A/D
A/D conversion is performed by converters 72, 73, and 74, and the signals are sent to the next shading unit 59 via a buffer 65.

Then, when the optical system, that is, each illumination lamp 5, 6, etc. passes through the white calibration plate 19, a signal is sent from the main body control section 8, and the output level of each bit of each CCD light receiving unit 56, 57, 58 becomes constant. Correction is made by the shading unit 59 as shown in FIG. Next stage γ correction unit 6
For 0, an appropriate γ characteristic curve is selected by a signal from the main body control unit 8, γ correction is performed according to the curve, and then the subsequent masking processing unit 61 performs arithmetic processing on each of the B, G, and H color signals simultaneously. Color correction is performed by changing the mixing ratio of each color component. The mixing ratio of each color of B, G, and R is switched by a control signal from the main body control section 8.

Further, the information signal is processed by the UCR processing unit 62 as B,
The minimum signal among G and R is determined. The value obtained by multiplying the minimum signal by an arbitrary coefficient written in the ROM 120 selected by the signal from the main body control section 8 is set as the black level. Whether or not the value multiplied by the coefficient is subtracted from each color is determined by each ROM 117 selected by a signal from the main body control section 8.
This is done according to the contents of ゜118 and 119.

Therefore, among the signals of each color B, G, R, and BK, the selection signal (CS) of the main body control section
Among them, one color, No. 13, is sent to the line drawing processing circuit 123. Then, in the line drawing processing circuit 123, each 6-bit color signal is once held by a latch 124, and then branched into two circuits. For example, when the manual port P of the data selector 128 is selected by the select signal (CS), one branched signal passes through the shift register 127, and then passes through the input port P of the data selector 128 and the output port Pn. In terms of time, it takes several clocks to 1.0
The signal is sent to the subtraction circuit 129 with a delay of 00 clocks. Note that this delay time is determined by the select signal (CS) of the data selector 128 from the input boards p, p2 . It can be switched by selecting one of p3.

As mentioned above, the subtraction circuit 129 is composed of the two-manufactured EX-OR gate 130, so it inputs the direct human-powered signal from the latch 124 and the input signal via each of the foot registers 125 to 127! Compare the value with the 6-bit signal. If the values of the - signals are equal, the output is zero, and if the values of the t6 bit signals are different, the absolute value of the difference is output.

That is, when a document as shown in FIG. 5 is read by the CCD light receiving unit 56 as indicated by a point i1M, the output signal of the latch 124 becomes small as shown in FIG. 6 (1), while the shift register 125 is The missed signal is shown in Figure 6 (2)
become that way. At this time, if the human-powered boat P1 of the data selector 128 is selected, the above-mentioned FIG. 6(1)
The absolute value of the difference between and (2) is shown in (3) in the same figure.

If an image is reproduced based on the signals shown in Fig. 6 (1), (2), and (3), images as shown in Fig. 7, Fig. 8, and Fig. 9 will be reproduced, respectively. be done. 9th
As you can see from the reproduced image in the figure, the vertical lines are reproduced, but the horizontal lines disappear. Therefore, the delay time in the line drawing processing circuit 123 is increased, and the original image shown in FIG.
When reproduced using the output signal of , a reproduced image as shown in FIG. 11 is obtained.

Also, if each shift register 25, 126 and 12
7, the image is reproduced as shown in FIG. Subtraction circuit 129 obtained in this way
The output of the dither processing unit 1 is held in the latch 131.
32.

The dither processing unit 132 compares deep signals such as 6-bit signals using a ROM for table reference, converts them into digital signals of 1 or 0, and modulates the semiconductor laser 23. I do. Dither processing is performed by each dither processing block existing in parallel inside the dither processing unit 132, and the data obtained by the processing is sent to the multi-value processing unit 145, where selection control is performed by the main body control section 8. Signal processing is performed.

When the semiconductor laser 23 is driven via the laser driver 155 based on the obtained processing data and the image is reproduced, a line image as shown in FIG. 13 is obtained.

In addition, in the above explanation, one color was described among each color, but the above-mentioned operation was repeated four times to produce B and G.

By superimposing the respective colors of R and 8 (a more full-color reproduced image can be obtained. In other words, (1) by superimposing each of the signals of B, G, R, and B obtained by signal processing the image information of original 1, By reproducing the image using only one or two of the signals, it is possible to create a line drawing of only a specific color of the original image.

(2) For example, by reproducing an R color image using a B color signal, a line image subjected to color conversion can be created. That is, after processing the B color signal, laser modulation is performed using the B color signal, and at this time, a developing device having R color toner is selected to perform development.

(3) Also, a selection signal (C
S), each Kugata boat PI of the data selector 128,
By appropriately selecting P2 and Pa, the delay time of the line drawing processing unit is changed. For example, when the delay time is increased, thicker lines are obtained, so that line images of arbitrary thickness can be obtained.

(Other Embodiments) FIG. 4 is a line drawing processing circuit diagram showing another embodiment of the present invention in which the latch 131 and subsequent parts shown in FIG. 3 are changed.

In the figure, 157 is an OR gate connected to the output side of the latch 131, 158 is an R/W line memory, and 15
9 is a latch, 160 is a blanking circuit, and 161 is a pattern generator connected to the blanking circuit 160 for generating a pattern.

If the output of the latch 131 is a high signal even for 1 bit, the OR gate 157 connected to the latch 131 is connected to the OR gate 157! The output of 57 becomes high level. That is, if there is a difference between the output of the latch 131 and the signal passed through the shift register 125, the laser beam La is turned on, and if not, it is turned off. In FIG. 3, the density of the reproduced line drawing changes depending on the magnitude of the signal difference, but in FIG. 4, the density of the line drawing always remains constant as described above.

Furthermore, by ignoring the lower several bits of the 6-bit output of the latch 124 shown in FIG. 3, it is possible to reproduce as a line drawing only those areas where the difference in density is greater than a certain value.

〔Effect of the invention〕

As described above, according to the present invention, the density-changing portion of the original image is detected by the density detection means, and the detected cost is used by the image processing means to form a line image at a constant density independently of the density of the original image. By configuring it to perform image processing like this, it is possible to reproduce parts of the original image where the density changes as a line image, which makes it possible to reproduce the parts of the original image where the density changes as a line image.
It is now possible to easily obtain a simple reconstructed line image.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of an image processing device according to the present invention, FIG. 2 is a circuit block diagram of an image processing unit showing main parts of the invention, and FIG. 3 is a main part of FIG. Detailed drawing of the part,
FIG. 4 is a line drawing processing circuit diagram showing another embodiment of the present invention, FIGS. 5 and 10 are original image diagrams, and FIG. 6 is a diagram of the original image when the original image according to the present invention is read. Signal waveform diagrams, FIGS. 7 and 11 are explanatory diagrams of line images obtained when the original image according to the present invention is reproduced, and FIGS.
2 is an explanatory diagram of a line image when the original image according to the present invention is reproduced by delaying the signal, FIGS. 9 and 13.
The figure is an explanatory diagram of each image when the line images shown in FIG. 7 and FIG. 8 or the line images shown in FIG. 11 and FIG. 12 are synthesized, respectively. 56.57.58・----CCD light receiving unit (density detection means) 22... Image processing unit (image processing means)

Claims (1)

[Claims] The image forming apparatus is characterized by comprising a density detection means for detecting a density change part of the original image, and a line drawing processing means for performing line drawing processing to form a line image with a constant density regardless of the density of the original image. Image processing device.