JPH08335262A - Image processing apparatus and method thereof - Google Patents

Abstract

(57) [Summary] [Object] To provide an image processing apparatus and method capable of accurately determining a specific original regardless of the reading conditions of the original image. A shading correction circuit 103 performs shading correction on an input image signal in accordance with the type (reading condition) of the platen glass set in a platen glass type setting unit 113. The input masking circuit 104 converts the color space of the image signal output from the shading correction circuit 103 into the NTSC standard color space. The specific document determination unit 110 is
A specific document is detected from the image signal output from the input masking circuit 104.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus and a method thereof, for example, an image processing apparatus and a method thereof for detecting a specific original image included in an input image signal.

[0002]

2. Description of the Related Art A color printer that digitally processes and outputs color image data to a color printer to obtain a color image, or a color original is color-separated and electrically read, and the obtained color image data is recorded. The progress and spread of color printing systems such as so-called digital color copiers, which perform color image copying by printing out on paper, are remarkable. With the widespread use of these devices, the demands on the print quality of color images are increasing. In particular, there is an increasing demand for color reproducibility that more faithfully reproduces the color of a color original.

However, if an image is printed as it is based on a signal obtained by a CCD or the like, a difference in CCD characteristics between machines, uneven light amount when reading an original, a color reading space of a CCD and a color printer can be reproduced. Due to the difference with a different color space, faithful color reproduction cannot be performed. Therefore,
For differences in CCD characteristics and uneven light intensity when scanning documents, shading correction using a standard white plate
For the difference between the read color space and the color space that can be reproduced by a color printer, conversion to the NTSC standard color space is performed by matrix calculation.

As the performance of the above-mentioned color copying machine and the like is improved, illegal use of these devices has become a problem. That is, there is a problem in that these devices are illegally used for forgery of banknotes, securities, etc. (hereinafter, sometimes referred to as “specific document”). Therefore, there is a need for a technique for preventing the duplication of a specific manuscript, one of which is
Information indicating the distribution of the tint of a specific document is registered in advance in the color space, and it is determined whether the input image data is that of the specific document by comparing it with the distribution of the tint of the input image data. The applicant has proposed a technique of doing so.

In addition to this, the copying speed of the color copying machine has been increased, and it has become possible to use a large number of originals at one time. Therefore, when copying a plurality of originals at one time, there is one that uses a device (hereinafter referred to as “ADF”) that automatically feeds originals as an application.

[0006]

However, the above-mentioned technique has the following problems. In other words, when a document is fed by the ADF, it is moved on the platen by the conveyor belt, but at this time, static electricity is generated due to friction between the document and the platen glass, which causes the document to slip poorly. The document cannot be fed smoothly. Further, in the worst case, paper jam occurs.

In order to solve this problem, when the ADF is attached, the paper is smoothly fed on the document table.
Use glass that has an antistatic coating with a conductive film as the platen glass. However, since the antistatic coat is not colorless and transparent, there is a difference in white level and tint between the case where the glass provided with the antistatic coat is used and the case where it is not. Therefore, in the subsequent image processing, for example, there is a problem that the function of determining the specific document malfunctions.

The present invention is intended to solve the above-mentioned problems, and an object of the present invention is to provide an image processing apparatus and method capable of accurately determining a specific original regardless of the reading conditions of the original image. To do.

[0009]

[Means for Solving the Problems] and

The present invention has the following structure as one means for achieving the above object.

An image processing apparatus according to the present invention includes a reading unit for reading an original image, a setting unit for setting a reading condition of the reading unit, and an image signal output from the reading unit based on the reading condition. First processing means for performing image processing, detection means for detecting a specific document from the first image signal output from the first processing means, and the first image based on the detection result of the detection means A second processing means for performing image processing on the signal.

Further, reading means for reading the original image, setting means for setting the reading conditions of the reading means, first processing means for applying image processing to the image signal output from the reading means, and the reading means. Detecting means for detecting a specific document from the first image signal output from the first processing means based on a condition; and performing image processing on the first image signal based on the detection result of the detecting means. And a second processing means.

According to the image processing method of the present invention, the reading step of reading the original image by the reading means and the image signal obtained in the reading step based on the set reading conditions of the reading means are subjected to image processing. Processing step, a detection step of detecting a specific document from the first image signal obtained in the first processing step, and image processing of the first image signal based on the detection result of the detection step. And two processing steps.

Further, the reading step of reading the original image by the reading means, the first processing step of applying image processing to the image signal obtained in the reading step, and the first processing step based on the set reading condition of the reading means. A detection step of detecting a specific document from the first image signal obtained in one processing step; and a second processing step of performing image processing on the first image signal based on the detection result of the detection step. It is characterized by

[0014]

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

[Structure] FIG. 1 is a schematic view of an image processing apparatus according to the first embodiment of the present invention, showing an example of a color copying machine having one drum system.

In the figure, reference numeral 3201 denotes an image scanner section, which is a section for reading an original image and subjecting the image data to digital signal processing. A printer unit 3200 is a unit that outputs an image corresponding to the original image read by the image scanner unit 3201 on a recording sheet in full color.

In the image scanner unit 3201, the original 3204 sandwiched between the original pressing plate 3202 and the original table glass 3203 is
It is illuminated by the light of the halogen lamp 3205. Reflected light from the original is guided to mirrors 3206 and 3207, and an image is formed on a 3-line sensor (hereinafter referred to as “CCD”) 3210 by a lens 3208.
The lens 3208 is provided with an infrared cut filter 3231. In addition, the halogen lamp 3205 is provided in a direction (sub scanning direction) perpendicular to the electrical scanning direction (main scanning direction) of the CCD 3210.
The mirror 3206 scans the entire surface of the original 3204 by mechanically moving at a speed V and the mirror 3207 at V / 2.

The CCD 3210 color-separates the reflected light from the original to obtain full color information of red (R), green (G) and blue.
The component (B) is read and its RGB signal is sent to the signal processing unit 3209. The sensor array of the CCD3210 that reads each color component is composed of 5,000 pixel elements. As a result, the maximum size original that can be placed on the platen glass 3203 and the A3 size original in the lateral direction (297 mm) can be read at a resolution of 400 dpi.

Further, the standard white plate 3211 is an R, G, B sensor 321.
It is for generating data that corrects the reading characteristics of each of 0-1 to 3210-3, and is a white color that shows almost uniform reflection characteristics in visible light.

The signal processing unit 3209 electrically processes the input image signal to generate magenta (M), cyan (C) and yellow.
Decompose into (Y) and black (K) components and send to the printer unit 3200. It should be noted that one image component of M, C, Y, and K is sent to the printer unit 3200 for each document scanning (scanning) in the image scanner unit 3201. The printout is completed.

In the printer unit 3200, the laser driver
3212 is the MCYK sent from the image scanner unit 3201.
The semiconductor laser 3213 is driven according to the image signal. Laser light output from the semiconductor laser 3213 scans the photosensitive drum 3217 via a polygon mirror 3214, an f-θ lens 3215, and a mirror 3216. The photosensitive drum 3217 is alternately in contact with four developing devices of a magenta developing device 3219, a cyan developing device 3220, a yellow developing device 3221 and a black developing device 3222. On the photosensitive drum 3217, M, C, Y and K electrostatic latent images are formed. The toner corresponding to each image is developed.

The recording paper supplied from the recording paper cassette 3224 or 3225 is wound around the transfer drum 3223, and the developed toner image is transferred onto the photosensitive drum 3217. In this way, the recording paper on which the four color toner images of M, C, Y and K are sequentially transferred is discharged through the fixing unit 3226.

In this embodiment, in order to reproduce the halftone of the image, the lighting time of the semiconductor laser 3213 is controlled according to the image density signal by the known PWM method.
As a result, an electrostatic latent image having a potential corresponding to the lighting time of the semiconductor laser 3213 is formed on the photosensitive drum 3217, and the developing device 3219
By 3222, the density (halftone) is reproduced by developing the latent image with the toner amount according to the potential of the electrostatic latent image.

[CCD] FIG. 2A is a diagram showing a configuration example of the CCD 3210,
FIG. 2B is a diagram showing an arrangement example of light receiving elements, and FIG. 2C is a diagram showing an example of a sectional structure of CCD 3210.

As mentioned above, 3210-1 shown in FIG. 2A is red.
(R) Light receiving element array for reading wavelength components, 3210-2 is green (G)
A light receiving element array for reading a wavelength component, and 3210-3 is a light receiving element array for reading a blue (B) wavelength component. As shown in FIG. 2B, the light receiving element array having these three different optical characteristics is
Approximately 80 μm in the sub scanning direction to read the same line of the original
The elements are arranged in parallel with each other at intervals of (8 lines), and each element has an opening of about 10 μm in the main scanning direction and the sub scanning direction.

These light receiving element arrays are monolithically formed on the same silicon chip, and by using a CCD having such a structure, an optical system such as a lens for separating and reading each color can be shared. It is possible to simplify the optical adjustment for each of R, G, B.

FIG. 2C shows an example of a sectional structure of the CCD 3210 in the sub-scanning direction, in which light receiving element rows 3210-1 to 3210-3 for reading R, G and B are arranged on a silicon substrate 3210-5. There is.
Then, on the R light receiving element row 3210-1, among the visible light, red (R)
An R filter 3210-7 that transmits wavelength components is arranged, and similarly, a G filter 3210-8 is provided on the G light receiving element array 3210-2, and a B filter 3210-9 is provided on the B light receiving element array 3210-3. Each is arranged. Further, a flattening layer 3210-6 made of a transparent organic film is formed between the light receiving element array and the filter and on the filter.

[Image Signal Processing Unit] FIG. 3 shows the signal processing unit 3209.
3 is a block diagram showing a configuration example of FIG.

In the figure, reference numeral 101 denotes an analog signal processing unit which performs gain adjustment and offset adjustment on the analog image signal input from the CCD 3210. An A / D converter 102 converts the analog image signal input from the Alain LOG signal processing unit 101 into, for example, an 8-bit digital image signal for each color.

A shading correction circuit 103 performs shading correction on the image signal input from the A / D converter 102 based on the read value of the standard white plate 3211. Here, the shading correction is to correct the optical system such as the unevenness of the light amount of the lamp 3205 that illuminates the original, the difference in the transmitted light amount depending on the position where the light passes through the lens 3208, and the sensitivity variation of each light receiving element that constitutes the CCD3210. Is. In other words, even if the CCD 3210 receives the reflected light from a document of uniform density,
A difference occurs in the output of the CCD 3210 when the light receiving position is near the end of the CCD 3210 and when it is near the center. Therefore, CCD
When the standard white plate 3211 (original with uniform density) is read in advance by the 3210, the correction coefficient for each pixel of the CCD3210 based on the read value is multiplied by the input image signal to read all pixels when the original with uniform density is read. Is corrected so that the read values of are equal.

FIG. 4 is a diagram for specifically explaining the shading correction. The value of pixel n when the standard white plate 3211 is read by the CCD 3210 is defined as a, and the actual density c of the standard white plate 3211 and the value a. The shading correction coefficient α is given by the following equation, where b (= ca) is the difference between and. α = b / a… (1)

Pixels n when a document is read by the CCD3210
Assuming that the value of is Y, the shading correction value K at that time is obtained by the following equation. K = α × Y (2)

Therefore, the image data Y'after the shading correction is expressed by the following equation. Y '= K + Y = Y (1 + b / a)… (3)

These calculations are performed by the ROM of the control unit (not shown).
Based on the actual density c of the standard white plate 3211 stored in, for example, the CPU of the control unit. The control unit controls the entire color copying machine of this embodiment.

Reference numeral 104 denotes an input masking circuit, which performs a shading correction circuit 103 by a matrix calculation such as the following equation.
Image signal output from CCD 3210 R, G, B filter 3210
Converts the read color space RGB determined by the spectral characteristics of -7 to 3210-9 to the NTSC standard color space R'G'B '. However, a11 to a33 are masking factors

Reference numeral 105 denotes a LOG conversion circuit, which is composed of a look-up table ROM, for example, and converts the RGB luminance signal output from the input masking circuit 104 into a CMY density signal.

Reference numeral 106 is a print signal generation circuit, and FIG. 5 is a block diagram showing an example of the configuration of the print signal generation circuit 106. 501 and 502 are masking UCR arithmetic circuits, respectively.
Although the YMCK density signal is generated from the CMY signal input from the OG conversion circuit 105, the masking UCR calculation circuit 502 changes the tint that is output when it is determined that the input image signal matches the specific document (for example, It produces a density signal (for example, darkening black). A selector 503 selects and outputs the output of the masking UCR calculation circuit 501 in the case of a non-specific document and the output of the masking UCR calculation circuit 502 in the case of a specific document according to a real-time correction signal f whose details will be described later.

In FIG. 3, reference numeral 107 denotes a scaling circuit, which enlarges or reduces the image signal and the black character determination signal input from the print signal generation circuit 106 in the main scanning direction by a well-known interpolation calculation.

Reference numeral 108 denotes a spatial filter, the details of which are omitted. The image signal input from the scaling circuit 107 is subjected to edge enhancement processing or smoothing processing based on a 2-bit filter signal. MCYK output from the spatial filter 108
The frame sequential image signal is sent to the laser driver 3212,
As described above, the halftone recording is performed by the PWM method.

Reference numeral 110 denotes a specific manuscript judgment unit, which is a color space matching judgment circuit 111 for calculating the similarity between the color distribution of the image data input from the input masking circuit 104 and the color distribution of the specific manuscript in real time, and color space matching. Judgment circuit 111
And a real-time correction signal generation circuit 112 that generates a real-time correction signal f based on the output of the.

A platen glass type setting unit 113 sends a signal GS indicating whether or not the platen glass 3203 is provided with an antistatic coat to the shading correction circuit 103.

Reference numeral 114 denotes a read synchronization signal generation circuit, which generates a clock (CLK), a main scanning section signal (HS), and a sub-scanning section signal (VS) for each pixel. These signals are supplied to each of the blocks described above, and are used as synchronization signals for image processing by each block.

[Specific Original Judgment Section] FIG. 6 is a block diagram showing a configuration example of the color space matching judgment circuit 111.

In the figure, reference numerals 1201 to 1203 denote R of the upper 5 bits of each color of the RGB signal output from the input masking circuit 104.
It is a GB signal. 1205 is a timing generation circuit that generates various timing signals described later, 1209 is SRAM, 1207 is SRAM 12
It is an address generator that sequentially generates all 09 addresses.

Reference numeral 1204 denotes a ROM, which stores information regarding the tint of a plurality of types of specific originals. When a 5-bit RGB signal for each color is input to the address terminals (A0 to A14) of the ROM1204, the signals (X0 to X7) indicating whether or not the input signal and each of multiple types of specific originals match Terminal (D0 ~ D
Output from 7).

1220 to 1227 are smoothing circuits, respectively,
Smoothing operation is performed on the determination signals (X0 to X7) output from 4. 1
Reference numerals 240 to 1247 are color space determination circuits, which calculate the similarity between the image data of the specific document and the input data in real time in the RGB space, and calculate the color space similarity determination signals (MK0 to MK7). Reference numerals 1271 and 1272 are selectors, which are used to clear the SRAM 1209 to zero according to the address signal generated by the address generator 1270 when the sub-scanning section signal VS is "0".

FIG. 7 is a diagram conceptually showing the information regarding the tint of a specific document stored in the ROM 1204. As shown in the figure, the tint information of the specific original is expressed by a three-dimensional color space having RGB color components as coordinate axes, and the shaded area corresponds to the tint of the specific original. And the entered RG
Whether the B signal is included in the area corresponding to the tint of the specific document is determined by the combination of the RGB coordinate values corresponding to the values of the input RGB signals, and the output is the tint of the specific document. '1' if matches and '0' otherwise
The input / output relationship is configured so that In other words, the ROM 1204 stores a table that outputs the value “0” or “1” according to the input RGB signal value. Note that the ROM 120 has eight decision signals D0 to D7.
This is because the tint information about eight types of specific originals is stored in 4, and each signal corresponds to one type of specific original. The specific manuscript is not limited to eight types.

FIG. 8 is a diagram for explaining the data relating to the tint of a plurality of specific originals stored in the ROM 1204, and shows the relationship between input data and output data. The B signal is input to the 5 bits of the input address terminals A0 to A4, and the G signal is input to the 5 bits of A5 to A9.
An R signal is input to each of the 5 bits A10 to A14. This input signal sets the address value,
The output regarding the similarity in color tones of the eight types of specific originals with respect to the input signal is determined. Then, for each color 5-bit RGB data for each pixel that is input, determination signals (X0 to X7) regarding the similarity of the tint of eight different specific originals are output in parallel from the data terminals (D0 to D7). It

FIG. 9 is a block diagram showing a configuration example of the smoothing circuits 1220 to 1227. 1601 and 1062 are multipliers, 1603 is an adder,
1604 is a latch and 1605 is a comparator.

The multipliers 1601 and 1602 and the adder 1063 calculate the weighted average of the sequentially input data Xi,
It is possible to make judgments that take continuity into account, as shown in 10 for example. FIG. 10 is a diagram showing the relationship between the input value Xi of the smoothing circuit and the smoothed operation value Yi, which has the characteristic that the smoothed operation value Yi increases in accordance with the input value Xi, and the input RGB signal is continuously specified. When the color tone of the original is matched, the smoothing calculation amount Yi exceeds the slice level α, the output (C0 to C7) of the smoothing circuit becomes '1', and it is more accurate without being affected by noise. Judgment becomes possible.

FIG. 11 is a block diagram showing a configuration example of the color space determination circuits 1240 to 1247. In the RGB space as shown in FIG. 12, the similarity between the specific image data and the input RGB signal is calculated in real time. , Color space similarity determination signal (MK0 to MK
7) is calculated. That is, the data Di read from the SRAM 1209 and the outputs Ci of the smoothing circuits 1220 to 1227 are ORed.
The gates are logically ORed and the result is written back to SRAM1209.

Further, only when the data Di transits from "0" to "1", the counter 1301 which is cleared at the rising edge of the sub-scanning section signal VS is counted up. The comparator 1302 compares the output value Zi of the counter 1301 and the constant Δn of the register 1303 with each other, and when Zi> Δi, MKi =
'1' is output, and MKi = '0' is output when Zi ≦ δi.

Here, Zi is equal to the volume Uid of the shaded portion of the observed image data shown in FIG. 12, and δi is the volume of the shaded portion of the registered specific image data shown in FIG. A value related to the volume Uorg is set. δi = (1/100) × Uorg… (5)

Note that Uid is each color in the RGB coordinate space.
This is the volume of the area formed by dividing each coordinate axis into 32 with a predetermined unit length, taking into consideration possible values of 5-bit RGB data.

FIG. 13 is a timing chart showing each timing signal generated by the timing generation circuit 1205. CLK4 is a clock signal obtained by dividing the basic clock CLK by four, and / OE is the output enable (SOR) of the SRAM 1209 via the signal line 1208. OE)
A signal that is applied to the terminal and controls the output from SRAM1209,
/ WE is SRAM 1209 write enable via signal line 1207
This signal is applied to the (WE) terminal and controls data writing to SRAM1209. In addition, Ci, Ci ', Di, Di', Di ", ENB respectively indicate the interrelationship of the control signals or input / output signals shown in Fig. 11. In addition, they are added to the signals / OE and / WE. The symbol "/" indicates that those signals are negative logic.

By the above processing, when the observed image data, that is, the data of the input color signal sequence has substantially the same shape as the specific image data in the RGB color space,
The color space similarity determination signals (MK0 to MK7) are '1'.

FIG. 14 shows a real-time correction signal generation circuit 107.
In the block diagram showing the configuration example of, the input image data composed of a latch, an AND gate and an OR gate is
Matching in RGB color space with any of a plurality of specific originals registered in ROM 1204 indicates that the color space similarity determination signal (MK0 to MK
When it is indicated by 7), the real-time correction signal f is set to '1'.

[ADF] FIG. 15 is a schematic view showing an example of the structure of an ADF for automatically feeding originals when copying a plurality of originals at once.

The originals stacked on the original tray 200 are supplied in order from the lower side (the bottom page of the stacked originals) by the separation belt 204 and the conveying roller 205. After feeding the first page, the document tray 200 is lowered to prepare for document ejection. After copying the first document set on the platen glass 3203, at the same time as discharging the first document, the registration roller 215 supplies the second document on standby,
The first and second sheets are placed on the original platen glass 3203 at the same time and conveyed so that continuous feeding is performed. This continuous feeding is repeated and the original is discharged to the original tray 200.

FIG. 16 is a diagram showing an example of the operation of the ADF, showing an example in which the supplied original is switched back and discharged.

In this way, the originals are continuously supplied and discharged to perform continuous copying. However, at this time the platen glass
When the original is automatically conveyed on the 3203, the original glass 32
The friction between 03 and the document causes static electricity to be accumulated on the platen, which hinders the document from moving smoothly on the platen glass 3203, causing paper jams and damaging the document.

Therefore, as a measure against static electricity when the ADF is attached, a conductive film is coated on the surface of the platen glass 3203 (hereinafter referred to as "EC (electro conductive) coat"), and the potential of the EC coat is adjusted to the apparatus main body. An antistatic coat is provided so that static electricity due to friction between the document and the platen glass 3203 can be released by fixing it to the ground potential. As a result, static electricity is not accumulated on the platen, and the document can be moved smoothly.

However, since the EC coat is not completely transparent, the transmittance of the platen glass 3203 differs depending on the presence or absence of the EC coat. In other words, the level of the signal output from the CCD3210 is, when the EC-coated platen glass 3203 is used,
Compared to the case where the platen glass 3203 which is not EC-coated is used, it is 4 to 6% lower. Therefore, with the data for determining a specific original, which is set to perform the optimum determination without the EC coat, the optimum determination cannot be performed with the EC coat applied. As a result, if the specific original cannot be detected or if the general original is erroneously recognized as the specific original, an erroneous determination occurs.

Therefore, in this embodiment, the shading correction is performed by switching the coefficient of the shading correction circuit 103 depending on the presence or absence of the EC coat, so that the optimum determination of the specific original can be performed regardless of the presence or absence of the EC coat. is there.

Specifically, the platen glass type setting unit 113
Sets the type of glass attached as the platen glass 3203. That is, the platen glass type signal GS set according to the type of the platen glass by the operation unit of the present embodiment (not shown) is the shading correction circuit 10
Input to 3. The shading correction circuit 103 calculates the actual density value c of the standard white plate 3211 when the EC plate-uncoated platen glass 3203 is used when performing the shading correction calculation according to the platen glass type signal GS. Although it is used as it is, when the EC-coated platen glass 3203 is used, shading correction is performed using a density value larger than the actual density value c.

As a result, the shading correction circuit 103
Performs shading correction that makes it brighter than the original correction result, corrects the image signal that has become dark due to the difference in transmittance, that is, the signal level has decreased, and regardless of the difference in the document glass 3203, Image signals of the same level are output.

As described above, according to the present embodiment, the color space matching determination circuit 111 determines the specific original by using the signal value which is shading-corrected according to the type of the original platen glass. The specific original can be accurately determined regardless of the difference in glass.

[0068]

Second Embodiment An image processing apparatus according to the second embodiment of the present invention will be described below. It should be noted that in the second embodiment, substantially the same configurations as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

FIG. 17 is a block diagram showing an example of the arrangement of the signal processing section 3209 of the second embodiment, which is provided with two specific original document determination sections 110A and 110B similar to those described in the first embodiment. Then, the color space matching determination circuit 11 of the specific document determination unit 110A
The ROM 1204 for storing the tint information of the specific document included in 1 stores the information corresponding to the case where the platen glass 3203 is not EC-coated. Also, the RO of the specific document determination unit 110B
The M1204 stores information corresponding to the case where the platen glass 3203 is EC-coated.

In this way, the selector 115
According to the signal GS output from the platen glass type setting unit 113, the real-time correction signal fA output from the specific original determination unit 110A or the real-time correction signal fB output from the specific original determination unit 110B is selected, and the print signal is selected. Generator circuit
By inputting to 106, it is possible to detect the specific original by the specific original determination unit 110A in the case of the original platen glass 3203 which is not EC coated, and in the case of the original platen glass 3203 which is EC coated the specific original determination Part 110B makes it possible to detect a specific document.

[0071]

Third Embodiment An image processing apparatus according to the third embodiment of the present invention will be described below. In addition, in the third embodiment, substantially the same configurations as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

FIG. 18 is a block diagram showing a configuration example of the signal processing unit 3209 of the third embodiment, in which the signal GS of the platen glass type setting unit 113 is input to the color space matching determination circuit 111 of the specific document determination unit 110. It is a thing.

FIG. 19 is a block diagram showing a configuration example of the color space matching determination circuit 111. Each upper 5 bit RGB signal of the RGB signal output from the input masking circuit 104 is related to the tint of a plurality of types of specific originals. Information is input to two ROMs 1204A and 1204B in which information is stored. The ROM 1204A stores data corresponding to the original platen glass 3203 which is not EC-coated. Also, in ROM1204B,
Data corresponding to the EC-coated platen glass 3203 is stored.

By doing this, the selector 1273 causes
Depending on the signal GS output from the platen glass type setting unit 113, data Xi output from the ROM1204A or ROM1204B
Select the data Xi output from the smoothing circuit 1202-1227
In the case of the original platen glass 3203 that is not EC-coated, it is possible to detect a specific original by the ROM1204A, and the original platen glass that is EC-coated 32
In the case of 03, the ROM 1204B can detect the specific document.

The difference between the first embodiment and the third embodiment is that
Since only one ROM and selector 1273 are added to the embodiment, the increase in the circuit scale of the third embodiment can be suppressed to a small extent as compared with the second embodiment in which the entire specific document determination unit 110 is added. become.

[0076]

[Modifications] In each of the above-described embodiments, an example in which the type of the platen glass 3203 is externally set by the platen glass type setting unit 113 has been described, but the present invention is not limited to this.
It is also possible to attach a marker to the glass itself to indicate the type, and the apparatus body recognizes the marker to automatically switch the type of glass.

Further, in each of the above-described embodiments, an example in which the number of types of the original platen glass 3203 is two has been described, but the present invention is not limited to this, and a signal output from the original platen glass type setting unit 113. By setting GS to a plurality of bits and setting the shading coefficient and the specific document determination unit 110 or the ROM 1204 to three or more, it is possible to support three or more types of glass.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of 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.

[0080]

As described above, it is possible to provide an image processing apparatus and method for accurately determining a specific original regardless of the original image reading conditions.

[Brief description of drawings]

FIG. 1 is a schematic view showing a configuration example of an image processing apparatus according to an embodiment of the present invention,

FIG. 2A is a diagram showing a configuration example of the CCD 3210 shown in FIG.

FIG. 2B is a diagram showing an arrangement example of light receiving elements of the CCD3210,

FIG. 2C is a diagram showing an example of a sectional structure of a CCD3210,

3 is a block diagram showing a configuration example of a signal processing unit shown in FIG.

FIG. 4 is a diagram for specifically explaining shading correction,

5 is a block diagram showing a configuration example of a print signal generating circuit shown in FIG.

6 is a block diagram showing a configuration example of a color space matching determination circuit shown in FIG.

FIG. 7 is a diagram conceptually showing information about a tint of a specific document stored in a ROM,

FIG. 8 is a diagram for explaining data relating to color tones of a plurality of specific originals stored in a ROM,

9 is a block diagram showing a configuration example of a smoothing circuit shown in FIG.

FIG. 10 is a diagram showing a relationship between an input value Xi of a smoothing circuit and a smoothing operation value Yi,

11 is a block diagram showing a configuration example of a color space determination circuit shown in FIG.

FIG. 12 is a diagram for explaining the operation of a color space determination circuit,

13 is a timing chart showing each timing signal generated by the timing generation circuit shown in FIG.

14 is a block diagram showing a configuration example of a real-time correction signal generation circuit shown in FIG.

FIG. 15 is a schematic view showing an example of the structure of an ADF for automatically feeding a document,

FIG. 16 is a diagram showing an operation example of an ADF,

FIG. 17 is a block diagram showing a configuration example of a signal processing unit according to a second embodiment of the present invention,

FIG. 18 is a block diagram showing a configuration example of a signal processing unit according to a third embodiment of the present invention,

FIG. 19 is a block diagram illustrating a configuration example of a color space matching determination circuit according to a third exemplary embodiment.

[Explanation of symbols]

 3200 Printer section 3201 Image scanner section 102 A / D converter 103 Shading correction circuit 104 Input masking circuit 105 LOG conversion circuit 106 Print signal generation circuit 107 Magnification circuit 108 Spatial filter 110 Specific original judgment section 113 Original plate glass type setting section 114 Read sync signal generator

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H04N 1/40 101A

Claims (7)

[Claims] 1. A reading unit for reading an original image, a setting unit for setting a reading condition of the reading unit, and a first processing unit for performing image processing on an image signal output from the reading unit based on the reading condition. Processing means, detection means for detecting a specific original from the first image signal output from the first processing means, and image processing on the first image signal based on the detection result of the detection means An image processing apparatus having a second processing means. 2. The first processing means performs shading correction according to the reading condition.
The image processing device described in 1. 3. A reading unit for reading a document image, a setting unit for setting a reading condition of the reading unit, a first processing unit for performing image processing on an image signal output from the reading unit, and the reading unit. Detecting means for detecting a specific original from the first image signal output from the first processing means based on a condition; and performing image processing on the first image signal based on the detection result of the detecting means. An image processing apparatus having a second processing means. 4. The detecting unit detects a specific document based on specific document information according to the reading condition. 4. The image processing device according to claim 3, wherein 5. The reading condition represents a type of a platen glass of the reading unit.
The image processing device described in any one of 1. 6. A reading step of reading an original image by a reading means, a first processing step of applying image processing to the image signal obtained in the reading step based on a set reading condition of the reading means, A detection step of detecting a specific document from the first image signal obtained in one processing step; and a second processing step of performing image processing on the first image signal based on the detection result of the detection step. An image processing method characterized by the above. 7. A reading step of reading an original image by a reading means, a first processing step of applying image processing to the image signal obtained in the reading step, and the first processing step based on the set reading condition of the reading means. A detection step of detecting a specific document from the first image signal obtained in one processing step; and a second processing step of performing image processing on the first image signal based on the detection result of the detection step. An image processing method characterized by the above.