JPH06253135A - Picture copying machine - Google Patents

Abstract

PURPOSE:To provide a picture copying machine not requiring preliminary scanning when the background color of an original picture is eliminated or the like. CONSTITUTION:When copying is started, a reader section reads a white level reference board and stores correction data to a shading correction section 153. Succeedingly reading of an original is started and a read by a CCD 151 is converted into a digital signal and the signal is subjected to shading correction and input masking processing, the result is inputted to a magnification processing section 155 and a background color detection section 170. When the presence of a background color is discriminated, a correction curve in response to a maximum original reflectance luminance Dmax is set to a gamma correction section 161. Moreover, when the absence of the background color is discriminated, a default gamma correction curve is set to the gamma correction section 161. Succeedingly, picture data are read from a memory section 158, correction processing is implemented by the gamma correction section 161 to send picture data from which a background color is eliminated to a printer section.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image copying apparatus, and more particularly, to an image copying apparatus for removing a background color of an original image, converting a designated color, forming an achromatic image into a single color, and moving a center.

[0002]

2. Description of the Related Art Conventionally, when a background color of a document image is removed in a color copying apparatus which does not have a page memory for storing the image data of the document, first a reading operation of the document image (hereinafter referred to as "prescan") is performed. After detecting the background color of the original, the number of times (usually 3
Or four times), the reading operation of the original image and the image processing by the background color information obtained by the prescan are repeated to complete the image copying.

Also, in the case of removing the background color of an original image in a color copying apparatus having a page memory, the prescan is also performed to detect the background color of the original, and then the original image is read again to perform page memory operation. The image data is stored in the image memory, the image data is output from the page memory for each color, and the image processing is repeated for each color using the background color information obtained by the pre-scanning to complete the image copying.

Further, when reading a document image in a color copying apparatus having no page memory for storing the image data of the document, first, a prescan is performed to detect the presence or absence of the document and the document position, and then, depending on the toner type. The image copying operation was completed by repeating the reading operation of the original image a number of times (usually 3 or 4 times). Also, when reading an original image in a color copying apparatus having a page memory, the prescan is also performed to detect the presence or absence of the original and the original position, and then the original image is read again to store the image data in the page memory. Then, the image data was output from the page memory for each color, and the image copying was completed. At this time, when the image is formed by moving it to the center of the recording paper (hereinafter referred to as “center movement”), the timing of reading the image data from the page memory is controlled based on the document position information obtained by the prescan. Was there.

[0005]

However, the above-mentioned conventional example has the following problems. That is, even in a color copying apparatus having a page memory, when performing background color removal of an original image, color conversion of a designated color, monochromatic formation of an achromatic image and center movement, the original image is read again after performing prescan. Since the operation is performed, there is a drawback that the time required for image copying becomes long.

[0006]

SUMMARY OF THE INVENTION The present invention is intended to solve the above problems, and has the following structure as one means for solving the above problems. That is, a reading unit that reads a document image, a detecting unit that detects predetermined color information or color information from the image data output from the reading unit, and a storage unit that stores the image data output from the reading unit, An image copying apparatus including a correction unit that corrects the image data stored in the storage unit according to the detection result of the detection unit, and a forming unit that forms an image from the image data corrected by the correction unit. To

Further, reading means for reading the original image, detecting means for detecting positional information of the original from the image data output from the reading means, and storage means for storing the image data output from the reading means. An image copying apparatus including a reading unit that reads the image data stored in the storage unit according to the detection result of the detecting unit, and a forming unit that forms an image from the image data read by the reading unit. To

[0008]

With the above arrangement, an image copying apparatus for detecting predetermined color information or color information from the image data output from the reading means and correcting the image data according to the detection result to form an image. Can be provided. Further, with the above configuration, the image copying apparatus which detects the position information of the document from the image data output from the reading unit and reads the image data stored in the storage unit according to the detection result to form an image. Can be provided.

For example, with the above-described configuration, it is not necessary to perform prescan when performing background color removal of the original image, color conversion of the designated color, monochromatic formation of the achromatic image, and center movement. You can prevent it from lingering.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image copying apparatus according to an embodiment of the present invention will be described in detail below with reference to the drawings.

[0011]

[First Embodiment] [Reader Unit] FIG. 1 is a diagram showing a configuration example of a reader unit of an image copying apparatus according to the present embodiment. In the figure, 117 is a platen glass on which a document 118 is placed.
Reference numeral 119 denotes a DC motor, which is connected to the first carriage 104 and the second carriage 1 by a wire and a pulley (both not shown).
Drive 05. The DC motor 119 is turned on / off by the CPU 112 via the control line 114 as shown in FIG.
FF, rotation direction, brake ON / OFF, rotation speed, etc. are controlled. In FIG. 2, an up / down counter 113 counts encoder pulses output from the DC motor 119 for each predetermined rotation angle via the control line 115, and outputs a rotation direction signal output from the DC motor 119. To switch the count up / down.

Referring again to FIG. 1, the first carriage 104
Is the circumferential speed V of the pulley pivotally supported by the DC motor 119.
The second carriage 105 moves at half speed V.
Move by / 2. 107 is a home position sensor, 1
Reference numeral 06 denotes a D-TOP sensor provided at the leading end position of the document, both of which are composed of a photo interrupter or the like.

Reference numeral 108 denotes a shield plate attached to the first carriage 104, which includes the home position sensor 107 and the D-
It works to block the optical axis of the TOP sensor 106. 110
Is a light source, and the light emitted from the light source 110 is the original 102.
Is reflected by the lens 109, passes through mirrors 120, 121, 122, and is imaged on the CCD 151 by the lens 109. The CCD 151 has a red R, green G,
It has a filter of three colors of blue B and outputs an analog RGB signal proportional to the intensity of the reflected light from the original.

[Image Processing Circuit] FIG. 3 is a block diagram showing a configuration example of the image signal processing circuit of the reader unit 101. In the figure, reference numeral 151 denotes the above-mentioned CCD, which is provided with an optical filter of RGB three colors and outputs an RGB image signal of the read original. Reference numeral 152 denotes an A / D & S / H unit which converts the analog RGB image signal input from the CCD 151 into, for example, 8-bit digital RGB image data.

Reference numeral 153 is a shading section, which is an A / D & S
Shading correction is applied to the RGB image data input from the / H unit 152. 154 is an input masking section,
Masking correction is applied to the RGB image data input from the shading unit 153. 155 is a scaling processing unit,
When the scaling mode is set, scaling processing is performed on the RGB image data input from the input masking unit 155.

Reference numeral 158 denotes a memory unit, which will be described in detail later, but is controlled by the memory control unit 174 to control the scaling processing unit 15.
It stores the RGB image data input from 5, and outputs the stored RGB image data. Reference numeral 156 denotes a logarithmic conversion unit which converts RGB image data representing the brightness of the image input from the memory unit 158 into, for example, 8 units representing the image density.
Convert to bit CMY image data.

A masking / UCR unit 160 masks and UCRs the CMY image data input from the logarithmic conversion unit 156 and outputs, for example, 8-bit CMYK image data. A γ correction unit 161 is a CM input from the masking / UCR unit 160 according to an output of a background color detection unit 170, the details of which will be described later.
Γ correction is applied to the YK image data.

Reference numeral 162 denotes an edge emphasizing unit, which is a γ correction unit 161.
The edge enhancement processing is applied to the CMYK image data input from. A video processing unit 163 is an edge enhancing unit 162.
Depending on the CMYK image data input from
The laser beam is modulated and output. [Printer Unit] FIG. 4 is a schematic view showing a configuration example of the image copying apparatus of the present embodiment.

In the figure, 101 is the above-mentioned reader unit,
Reference numeral 102 is a document feeder section, and 103 is a printer section.
In the printer unit 103, a polygon scanner 301 scans a laser beam output from the video processing unit 163 to expose a predetermined position of a photosensitive drum of image forming units 302 to 305 described later.

Reference numeral 302 is an M image forming portion, 303 is a C image forming portion, 304 is a Y image forming portion, and 305 is a K image forming portion, which form images of corresponding colors. Since the configurations of the image forming units 302 to 305 are substantially the same, the details of the M image forming unit 302 will be described below, and the description of the other image forming units will be omitted. In the M image forming unit 302, 318 is a photosensitive drum, on which a latent image is formed by the laser beam from the polygon scanner 301.

Reference numeral 315 denotes a primary charger, which is a photosensitive drum 318.
The surface of is charged to a predetermined potential, and preparation for latent image formation is performed. A developing device 313 develops the latent image on the photosensitive drum 318 to form a toner image. A developing bias is applied to the developing unit 313, and a sleeve 314 for developing is applied.
It is included.

Reference numeral 319 denotes a transfer charger, which is the transfer belt 306.
Then, the toner image on the photosensitive drum 318 is transferred to a recording sheet or the like on the transfer belt 306. The surface of the photosensitive drum 318 after the transfer is cleaned by the cleaner 317, the charge is removed by the auxiliary charging device 316, the residual charge is erased by the pre-exposure lamp 330, and the primary charging device 315 again works well. So that you can get a good charge.

Next, a procedure for forming an image on a recording paper or the like will be described. Reference numeral 308 denotes a paper feeding unit, which is a cassette 309, 3
The recording paper stored in 10 is supplied to the transfer belt 306. The recording paper supplied from the paper supply unit 308 is charged by the adsorption charging device 311, and 312 is a transfer belt roller that rotates the transfer belt 306 and forms a pair with the adsorption charging device 311 for recording. Charge paper by adsorption.

Reference numeral 329 denotes a paper front end sensor, which is a transfer belt 30.
The leading edge of the recording paper on 6 is detected. Paper edge sensor 32
The detection signal 9 is sent from the printer unit 103 to the reader unit 101.
And is used by the reader unit 101 as a sub-scanning synchronization signal. After that, the recording paper or the like is conveyed by the transfer belt 306, and is transferred to the MCY in the image forming units 302 to 305.
Toner images are formed in the order of K.

The recording paper or the like that has passed through the K image forming section 305 is separated from the transfer belt 306 after being discharged by the discharging charger 324 in order to facilitate separation from the transfer belt 306. A peeling charger 325 prevents image disturbance due to peeling discharge when the recording paper or the like is separated from the transfer belt 306.

For the separated recording paper or the like, the pre-fixing charger 32 is provided in order to supplement the toner suction force and prevent image disturbance.
After being charged by 6,327, the fixing device 307 thermally fixes the toner image. On the other hand, the transfer belt 306 from which the recording paper and the like have been separated is destaticized by the transfer belt decharging chargers 322 and 323, is electrostatically initialized, and the dirt is removed by the belt cleaner 328. Preparations for adsorbing etc. are made.

In the case of the printer of this embodiment in which the positions of the image forming portions for each color are different from each other, at a certain point of time,
Since the positions on the image of the image data required by the image forming units are different from each other, the storage unit (the memory unit 1 in the case of the present embodiment is used as a delay unit for compensating for the temporal shift.
58) is required. [Memory Unit] FIG. 5 shows a memory unit 158 and a memory control unit 17.
4 is a block diagram showing a configuration example of No. 4.

In the figure, reference numeral 182 is an X-direction counter, which counts down the pixel clock VCK input to the clock terminal according to the state of the signal ROT1 and outputs a count value of 11 bits, for example. A Y-direction counter 183 counts down the main scanning synchronization signal Hsync input to the clock terminal according to the state of the signal ROT2 and outputs a count value of 11 bits, for example.

Numeral 184 denotes a selector a, which is X inputted to the terminal A according to the state of the signal ROT0 inputted to the selection terminal S.
Either the count value of the direction counter 182 or the count value of the Y direction counter 183 input to the terminal B is selected and output. 185 is a selector b, which is a selection terminal S
Depending on the state of the signal ROT0 input to the terminal, either the count value of the Y-direction counter 183 input to the terminal A or the count value of the X-direction counter 182 input to the terminal B is selected and output. To do.

A coordinate-address converter 186 outputs, for example, an address value of 10 bits corresponding to the count value input from the selector a 184 to the terminal X and the count value input from the selector b 185 to the terminal Y. The address value is the address terminal A of the memory unit 158.
Input to D. 187 is a memory controller, which is a signal RA
It outputs memory control signals such as S, CAS, and WE. The control signal is input to the corresponding control terminal of the memory unit 158.

That is, when the address value is given from the memory control unit 174 to the image memory 172, the signals ROT2 and ROT are used.
By controlling the signals of 1 and ROT0, for example, 3 bits, it is possible to perform, for example, 8 types of image processing as an example shown in FIG. [Undercolor Removal] In the above-described image copying apparatus of the present embodiment, the detection of the background color information of the original and the input of the original image data into the memory are performed substantially at the same time, and the output from the memory based on the detected background color information. A method of processing image data and forming a copied image by the printer unit 103 will be described.

After the document is set on the platen glass 117 by the operator and the background color removal is instructed by the operation unit (not shown) of this embodiment, the copy start button (not shown) is pressed. Then, the present embodiment starts the copying operation.
First, the reader unit 101 reads a white reference plate (not shown) arranged near the platen glass 117 and stores the correction data in the shading correction unit 153.

Next, when the DC motor 119 rotates to start the reading operation of the original and the shield plate 108 attached to the first carriage 104 crosses the D-TOP sensor 106, the main scanning counter starts counting. . The image signal read by the CCD 151 is converted into a digital signal, subjected to shading correction and input masking processing, and then subjected to a scaling processing section 155 and a background color detection section 170.
Is input to.

FIG. 7 is a block diagram showing an example of the structure of the background color detecting section 170, and FIG. 8 is a flow chart showing an example of the background color processing. In the same figure, in step S1, the background color detection unit 170 fetches into the memory 1702, for example, the data of 2,500 pixels of 50 pixels in the main scanning direction and 50 lines in the sub scanning direction shown in FIG.

Subsequently, in step S2, the arithmetic unit 1701
Thus, the data R (m,
n), G (m, n), B (m, n) to original reflection brightness D (m, n) of each pixel
Calculate n). Here, the document reflection brightness D (m, n) is defined by the following equation. D (m, n) = {R (m, n) + G (m, n) + B (m, n)} / 3 Then, in step S3, the reflection brightness D (m, n) of the original document is preset. The number of pixels existing in the range of the brightness variation width is determined, and if the number of pixels is equal to or larger than a predetermined value, it is determined that the original has a background color. Assuming that the number of pixels existing in the range of the reflection brightness variation width is n, the determination condition of the original document having the background color is as follows.

When it is determined that n / 2,500 ≧ 0.3 base color is present, a correction curve corresponding to the maximum document reflection brightness Dmax is set in the γ correction section 161 in step S4. If it is determined that there is no background color, a default γ correction curve is set in the γ correction unit 161 in step S5. Note that FIG. 10 is a diagram showing an example of a correction curve according to Dmax, and is an example when K <J, for example.

Then, in step S6, the printer unit 10
The image data from which the undercolor is removed is sent to the printer unit 103 by reading the image data from the memory unit 158 and performing the correction process in the γ correction unit 161 in synchronization with the operation of No. 3. As described above, according to the present embodiment, even when the background color removal of the original is specified by the operator, it is possible to form the copy image from which the background color is removed by performing only one reading operation of the original image. You can

[0038]

[Second Embodiment] A second embodiment of the present invention will be described below. In the second embodiment, the same components as those in the first embodiment are designated by the same reference numerals and detailed description thereof will be omitted. In the first embodiment, the background color of the original is removed by one reading operation, but in the second embodiment, the color conversion of the designated color is performed by one reading operation.

FIG. 11 is a block diagram showing a configuration example of the second embodiment, and FIG. 12 is a block diagram showing a configuration example of the color conversion unit 173. After the operator designates the position of the color to be converted on the original (hereinafter referred to as "designated position") and the color after conversion (hereinafter referred to as "converted color"), the present embodiment starts the copying operation. The designated position is input by an input device such as a digitizer.

When the document image is started to be read by the reader unit 101 and the image data of the document is stored in the memory unit 158, and at the same time when the first carriage 104 reaches the designated position, the designated color detection unit 171 The color data at the designated position is set in the register 1731 of the color conversion unit 173. Then, in synchronization with the operation of the printer unit 103, the memory unit 158
The image data read from is sent to the comparator 1732 and the delay unit 1733 of the color conversion unit 173.

The image data input to the comparator 1732 is compared with the color data at the designated position set in the register 1731, and the comparison result is input to the selection terminal S of the selector 1735. On the other hand, the image data passed through the delay unit 1733 is sent to the selector 1735,
The reference numeral 35 outputs either one of the image data input from the delay unit 1733 or the register 1734 according to the comparison result from the comparator 1732.

That is, when the color data at the specified position and the image data match, the color converter 173 uses the register 17
The preset color data is output to 34, and when the two data do not match, the image data read from the memory unit 158 is output as it is. As described above, according to this embodiment, even when the color conversion of the designated color is designated by the operator, the copy image in which the designated color is color-converted is formed by performing the reading operation of the original image only once. be able to.

[0043]

[Third Embodiment] A third embodiment of the present invention will be described below. In the third embodiment, the same components as those in the first embodiment are designated by the same reference numerals and detailed description thereof will be omitted. In the third embodiment, in the case of a monochrome (achromatic) image original, a so-called auto color select (hereinafter referred to as "ACS") for forming a copy image with a single color of K toner is performed by one reading operation. is there.

FIG. 13 is a block diagram showing a configuration example of the third embodiment. When an original is set on the platen glass 117 by an operator and ACS is instructed by an operation unit (not shown) of the present embodiment, and a copy start button (not shown) is pressed, the present embodiment is performed. The example starts a copy operation. When the reading of the document image by the reader unit 101 is started, the image data of the document is stored in the memory unit 158, and at the same time, the achromatic color detection unit 175 calculates the achromatic color coefficient X for each pixel. The achromatic color coefficient X is obtained by the following equation, for example.

X = Max (R, G, B) -Min (R, G, B) where Max (R, G, B) is the maximum of R, G, B data Min (R, G, B) B): Minimum of R, G, B data Subsequently, the achromatic color detection unit 175 determines the predetermined threshold value Y.
And the achromatic color coefficient X are compared. If X <Y, it is determined that the pixel is achromatic, and if all the pixels are achromatic, the achromatic signal X1 is sent to the selection terminal S of the selector 176.
To send.

The achromatic color calculation unit 177 is connected to the logarithmic conversion unit 156.
The achromatic color data Z is calculated from the CMY data output from. It should be noted that the achromatic color data Z is obtained by the following equation, for example. Z = (C + M + Y) / 3 Then, in synchronization with the operation of the printer unit 103, the image data read from the memory unit 158 is input to the selector 176. In the selector 176, the CMY input from the masking / UCR unit 160 according to the achromatic color signal X1.
Either K data or Z data input from the achromatic color calculation unit 177 is output. For example, when all the pixels are achromatic, the achromatic color signal X1 becomes the "L" level, and the selector 176 outputs Z data as K data and "00" as other CMY data.

As described above, according to this embodiment,
Even when the operator specifies ACS, the original image reading operation is performed only once, and a monochrome image original forms a copy image in a single color, and a colored image original CMYK.
A copy image can be formed with four colors.

[0048]

[Fourth Embodiment] A fourth embodiment of the present invention will be described below. In the fourth embodiment, the same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. In the fourth embodiment, document detection and center movement are performed by one reading operation.

FIG. 14 is a block diagram showing a configuration example of the fourth embodiment. In the present embodiment, in order to reduce the storage capacity of the memory unit 158, a method of compressing and storing image data and expanding and reading it is adopted. That is, the CMY image data output from the logarithmic conversion unit 156 is compressed by the encoder 157 and stored in the memory unit 158, the compressed data read from the memory unit 158 is expanded by the decoder 159, and then input to the masking / UCR unit 160. To do.

In the image data compression / decompression method of this embodiment, for example, the color space is converted from CMY to L ^* a ^* b ^{* in} units of 4 × 4 pixels shown in FIG. 15, and then 384 bits (= 16 pixels ×).
Data of 8 bits × 3 colors) is converted into fixed length data of 32 bits, and vector quantization or orthogonal transform coding is used. FIG. 16 is a block diagram showing a configuration example of the document detection unit 181.

When an original is set on the original table glass 117 by an operator and a copy start button (not shown) is pressed, this embodiment starts the copy operation. Reader unit 1
When the reading of the original image is started by 01, the comparators 1811 to 1813 compare the RGB data with the values preset in the registers 1814 to 1816, respectively, and the comparison result is the main scanning noise removing unit 1817.
Is input to ~ 1819. Each of the main scanning noise removal units has, for example, seven delay devices D18 as shown in FIG.
31-1837 and an AND gate 1838. Each delay device D delays the comparison result input from the comparator by the timing of one pixel, and the AND gate 1838
ANDs the comparison result and the outputs of the seven delay devices D.
The outputs of the main scanning noise removal units 1817 to 1819 are AN
It is logically ANDed by the D gate 1820. Therefore, any one of the input RGB data is continuously registered in the register 181 as 8 pixels.
If the preset value of 4 to 1816 is exceeded, AND
The output of the gate 1820 becomes “H”.

As shown in FIG. 18, the sub-scanning noise removing unit 1821 has a FIFO memory 1842 for storing data for one line and three gates 184, for example.
1, 1843, and 1844, the signal input from the AND gate 1820 is the AND gate 1841.
Through the FIFO memory 1842. FIF
The signal input to the O memory 1842 is the OR gate 18
44 and the AND gate 1841 logically ANDs with the pixel at the same position in the main scanning direction of the next line. Counter 18
22 is a 4-bit counter for counting Hsync,
“H” is input to the OR gate 1844 and the AND gate 1843 every 16 lines. Therefore, every 16 lines, A
FIFO memory 184 input to ND gate 1841
The signal from 2 is reset, and the AND gate 1843 outputs the document determination result.

FIG. 19 is a diagram for explaining the original determination signal. FIG. 19A shows the original 118 placed on the original table glass 117, and FIG. 19B shows the originals in the lines λ1 to λ8. The judgment signal is shown. The document position determination unit 1823
A position where the original determination signal first becomes "H" (point P in FIG. 19) and a position where the original determination signal finally becomes "H" (point Q in FIG. 19) are set in the register d1824.

The memory control unit 174 uses the register d182.
The center movement is realized by reading the image data from the memory unit 158 in synchronization with the operation of the printer unit 103 based on the position information of the document set in the item 4. In this embodiment, when the original determination signal does not become "H", it is determined that the original is not set on the original table glass 117, and a message indicating "no original" is displayed on the operation unit (not shown). ) Is displayed.

As described above, according to this embodiment,
Even when the document is detected and the center is moved, the copy image can be formed by performing the document image reading operation only once. The present invention may be applied to a system including a plurality of devices or an apparatus including a single device.

Further, it goes without saying that the present invention can be applied to the case where it is achieved by supplying a program to a system or an apparatus.

[0057]

As described above, according to the present invention, an image in which predetermined color information or color information is detected from the image data output from the reading means, and the image data is corrected according to the detection result to form an image. A copying machine can be provided. Further, according to the present invention, there is provided an image copying apparatus which detects the position information of a document from the image data output from the reading unit and reads the image data stored in the storage unit according to the detection result to form an image. Can be provided.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration example of a reader unit of an image copying apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating control of the DC motor of FIG.

3 is a block diagram showing a configuration example of an image signal processing circuit of the reader unit in FIG.

FIG. 4 is a schematic view showing a configuration example of an image copying apparatus of this embodiment.

5 is a block diagram showing a configuration example of a memory unit and a memory control unit of FIG.

FIG. 6 is a diagram showing an example of image processing according to the present embodiment.

FIG. 7 is a block diagram showing a configuration example of a base color detection unit in FIG.

FIG. 8 is a flow chart showing an example of background color processing of the present embodiment.

FIG. 9 is a diagram showing an example of a pixel group used for base color detection in the present embodiment.

FIG. 10 is a diagram showing an example of a correction curve according to the maximum document reflection luminance Dmax of the present embodiment.

FIG. 11 is a block diagram showing a configuration example of a second embodiment according to the present invention.

12 is a block diagram showing a configuration example of a color conversion unit in FIG.

FIG. 13 is a block diagram showing a configuration example of a third embodiment according to the present invention.

FIG. 14 is a block diagram showing a configuration example of a fourth embodiment according to the present invention.

FIG. 15 is a diagram illustrating pixels used for image data compression according to the fourth embodiment.

16 is a block diagram showing a configuration example of a document detection unit in FIG.

FIG. 17 is a block diagram showing a configuration example of a main scanning noise removal unit in FIG.

18 is a block diagram showing a configuration example of a sub-scanning noise removal unit in FIG.

FIG. 19 is a diagram illustrating a document determination signal according to the fourth embodiment.

[Explanation of symbols]

 101 reader section 103 printer section 117 original table glass 151 CCD 152 A / D & S / H section 153 shading section 154 input masking section 155 scaling processing section 156 logarithmic conversion section 157 encoder 158 memory section 159 decoder 160 masking / UCR section 161 γ correction Section 162 edge enhancement section 163 video processing section 170 base color detection section 171 designated color detection section 173 color conversion section 174 memory control section 175 achromatic color detection section 177 achromatic color calculation section 181 original detection section 301 polygon scanner 302 M image forming section 303 C image forming unit 304 Y image forming unit 305 K image forming unit 308 paper feeding unit 312 transfer belt roller 313 developing unit 318 photosensitive drum

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H04N 1/46 9068-5C

Claims (8)

[Claims] 1. A reading unit for reading an original image, a detecting unit for detecting predetermined color information from the image data output from the reading unit, and a storage unit for storing the image data output from the reading unit. It has a correction means for correcting the image data stored in the storage means according to the detection result of the detection means, and a forming means for forming an image from the image data corrected by the correction means. Image copying machine. 2. The image copying apparatus according to claim 1, wherein the correction unit removes the predetermined color information detected by the detection unit from the image data. 3. The image copying apparatus according to claim 2, wherein the predetermined color information is background color information of a document. 4. The image copying apparatus according to claim 1, wherein the correction unit changes the predetermined color information detected by the detection unit included in the image data into another color information. 5. A reading unit for reading an original image, a detecting unit for detecting color information from image data output from the reading unit, a storage unit for storing the image data output from the reading unit, and the storage unit. An image comprising: a correction unit that corrects the image data stored in the unit according to a detection result of the detection unit; and a forming unit that forms an image from the image data corrected by the correction unit. Copying device. 6. The image copying apparatus according to claim 5, wherein the correction unit outputs only black data when the detection unit detects that the color is achromatic. 7. A reading unit for reading a document image, a detecting unit for detecting document position information from image data output from the reading unit, and a storage unit for storing the image data output from the reading unit. A read unit that reads the image data stored in the storage unit according to the detection result of the detection unit; and a forming unit that forms an image from the image data read by the read unit. Image copying machine. 8. The reading means reads the image data from the storage means based on the detection result of the detection means so that an image is formed on a substantially central portion of the recording paper. Image copying machine.