JPH08287313A - Image read device - Google Patents

Abstract

PURPOSE: To prevent a paper money, etc., placed at an optional position and an optional angle from being forged by detecting the position and angle of the paper money, etc., judging from the part of the texture, detecting a cinnabar seal impression, and matching its pattern. CONSTITUTION: At the time of a 1st scan, an image scanner 201 detects the rough position of the watermark of a 10,000-yen bill and a printer part 202 performs magenta output. At the time of a 2nd scan, the image scanner 201 detects the accurate position and angle of the bill. At the time of a 3rd scan, the image scanner 201 calculates the position of the watermark of the 10,000-yen bill calculated from the detected position and angle, extracts and stores the cinnabar seal impression in a memory, and decides whether or not the cinnabar seal impression is genuine. The printer part 202 performs yellow output. At the time of a 4th scan, the image scanner 201 performs a concrete process for prevention against forging when it is decided at the time of the 3rd scan that forging is attempted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading device.

[0002]

2. Description of the Related Art Conventionally, as image quality and color of copying machines have increased, there has been a fear of forgery of banknotes. On the other hand, in recognition of bills and the like, various methods have been devised, such as Furukai 50-60090.

[0003]

In order to carry out the above-mentioned recognition with high accuracy, it is preferable to take a sufficient amount of time for processing and to recognize by various recognition methods.

However, when the above-mentioned recognition is performed by the image signal generated by one scanning, there is a problem that the load of the recognition processing is large.

An object of the present invention is to reduce the load of recognition processing and realize good recognition.

[0006]

A first color component signal is generated during a predetermined one of a plurality of scans of a target image, and a second color component signal is generated during a scan different from the predetermined one. Scanning Means for Generating Color Component Signals First identification means for identifying whether or not the target image is a predetermined image by using a first identification criterion in generating the first color component signals of the scanning means. Second identifying means for identifying whether or not the target image is the predetermined image by using a second identification criterion different from the first identification criterion when the second color component signal of the scanning means is generated; It is characterized by having.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Based on the preferred embodiments,
The present invention will be described.

In the following embodiments, a copying machine is shown as an application example of the present invention, but the present invention is not limited to this, and it is needless to say that it can be applied to various other apparatuses.

FIG. 2 shows an external view of the apparatus according to the first embodiment of the present invention.

In FIG. 2, reference numeral 201 denotes an image scanner section, which is a section for reading a document and performing digital signal processing. A printer unit 202 is a unit that prints out a full-color image corresponding to the original image read by the image scanner 201.

In the image scanner unit 201, 20
Reference numeral 0 is a mirror surface pressure plate, which is a platen glass (hereinafter, platen) 2
The original 204 on 03 is illuminated by a lamp 205, guided to mirrors 206, 207 and 208, and an image is formed on a 3-line sensor (hereinafter CCD) 210 by a lens 209.
The full-color information is sent to the signal processing unit 211 as red (R), green (G), and blue (B) components. 2
Reference numerals 05 and 206 are speed v, and reference numerals 207 and 208 are 1/2 v to scan the entire surface of the original by mechanically moving in a direction perpendicular to the electric scanning direction of the line sensor. The signal processing unit 211 electrically processes the read signal, and magenta (M), cyan (C), yellow (Y), black (B)
It is decomposed into each component of k) and sent to the printer unit 202. Further, one component of M, C, Y, and Bk is sent to the printer unit 202 for each document scanning (scanner) in the image scanner unit 201, and one printout is made by scanning the document four times in total. Complete.

The image signal of M, C, Y or Bk sent from the image scanner unit 201 is a laser driver 2
Sent to 12. The laser driver 212 modulates and drives the semiconductor laser 213 according to the image signal. The laser light is a polygon mirror 214, an f-θ lens 215, and a mirror 21.
The photosensitive drum 217 is scanned by way of the scanning line 6.

A rotary developing device 218 includes a magenta developing unit 219, a cyan developing unit 220, and a yellow developing unit 22.
1. The black developing unit 222 includes four developing units alternately contacting the photosensitive drum 217 to develop the electrostatic latent image formed on the photosensitive drum 217 with toner.

Reference numeral 223 denotes a transfer drum, which is a paper cassette 22.
The paper fed from No. 4 or 225 is wound around the transfer drum 223, and the image developed on the photosensitive drum 217 is transferred onto the paper.

After the four colors of M, C, Y and Bk are sequentially transferred in this manner, the paper passes through the fixing unit 226 and is discharged.

In the following, in the present embodiment, the anti-counterfeiting function of the 10,000-yen banknote of the Bank of Japan will be described in detail as an example of the manuscript to be protected from forgery, but the present invention is limited to such target. Of course not.

In this embodiment, a total of 4 as described above.
Copying is performed in a single reading operation (scan), and the operations of the image scanner 201 and the printer 202 at each scan are shown in FIG.

That is, when the forgery prevention of the 10,000-yen bill is attempted, the image scanner detects the rough position of the watermark of the 10,000-yen bill in the mode 1 at the first scanning. Then, the printer section outputs magenta.

During the second scan, the image scanner in mode 2 detects the exact position and the angle at which it is placed.

At the time of the third scan, the image scanner is in the mode 3 state and calculates the position of the red stamp of the 10,000-yen bill calculated from the position and angle detected in the second scan. , The red stamp is extracted and stored in the memory, and it is determined whether or not the red stamp is present. The printer unit outputs yellow.

At the time of the fourth scanning, the image scanner is in the state of mode 4, and if it is judged that the forgery is about to be performed at the time of the third scanning, the forgery preventing concrete processing is performed.

FIG. 5 is a timing chart showing the operation of each section in the image scanner section of this embodiment.

The VSYNC signal is an image effective section signal in the sub-scanning direction, and in the section of "1", image reading (scanning) is sequentially performed (C), (M), (Y), (B).
k) generate the output signal. VE is an image effective section signal in the main scanning direction, and the image becomes effective in the section of "1". The HSYNC signal is a main scanning synchronization signal and is "1".
The timing of the main scanning start position is set in the section. C
The LK signal is a pixel synchronizing signal and transfers image data at the rising timing of 0 → 1. CLK16 is a timing signal for every 16 pixels, and takes a timing of a 16 × 16 block-processed signal described later at the rising timing of 0 → 1.

(Image Scanner Section) FIG. 4 shows an internal block of the image scanner 201. 210-1, 21
Reference numerals 0-2 and 210-3 denote CCDs having spectral sensitivity characteristics of red (R), green (G), and blue (B), respectively, and a signal quantized to 8 bits from 0 to 255 is output.

Sensor 2 used in this embodiment
Since 10-1, 210-2, and 210-3 are arranged at a distance as shown in FIG. 1, the spatial shifts of the delay elements 401 and 402 are corrected.

Reference numerals 403, 404 and 405 are log converters, which are constituted by a look-up table ROM and convert a luminance signal into a density signal. Reference numeral 406 is a known masking and UCR circuit, and although detailed description thereof is omitted, Y, M, C, and
The Bk signal is sequentially output with a predetermined bit length, for example, 8 bits, for each reading operation.

Reference numeral 407 is an OR gate circuit, which takes a logical OR with the value held in the register 408. In the register 408, OO _H is normally written, and 406
Is output to the printer unit as it is, but at the time of anti-counterfeiting processing, the CPU 417 sets FF _H in the register 408 via the data bus to output an image painted with toner. .

A CPU 417 controls the device in each mode. A window comparator 408 determines whether or not a specific level signal instructed by the CPU 417 is input, and in modes 1 and 2,
The background level is detected, and in Mode 3, the red stamp is detected. The blow processing circuit 409 performs 16 × 16 block processing, and processes the output of the window comparator 408 for each 16 × 16 block.

Reference numeral 412 is a readable / writable random access memory (RAM), the data of which is switched by the selector 411 and the address of which is switched by the selector 413.

On the other hand, 419 is a main scanning counter,
It is reset by the SYNC signal and counted up at the timing of the CLK signal to generate 13-bit main scanning addresses (hereinafter X addresses) X12 to X0.

Reference numeral 420 is a sub-scanning address counter,
HSYNC is reset when the VSYNC signal is "0".
It is counted up at the timing of the C signal, and 13-bit sub-scanning addresses (Y addresses) Y12 to Y0 are generated.

The CPU 417 has selectors 411, 413, 415, 416 and an address decoder 4 according to each mode.
14 is controlled to read / write data from / to the RAM 412. 418 is an RA added to the CPU 417
M / ROM. A watermark detection circuit 410 detects a watermark portion of a bill.

FIG. 6 is a block diagram of the window comparator 408 shown in FIG. 601, 602, 603
Reference numerals 604, 605, and 606 are registers directly connected to the data bus of the CPU 417, and a desired value is written by the CPU 417.

607, 608, 609, 610, 61
Reference numerals 1 and 612 are comparators, which are A for inputs A and B.
The output becomes 1 only when> B is satisfied.

An AND gate 613 outputs 1 only when the outputs of all the comparators become 1, and outputs 0 otherwise. Now, registers 601, 60
2, 603, 604, 605 and 606 respectively have R _H ,
_{R L, G H, G L} , B H, when B _L becomes the value is written, the input signals R, G, B to R _L <R <R _H and G _L <G <G _H and B The output of the window comparator 408 becomes "1" only when _L <B < _BH is all satisfied, and becomes "0" otherwise.

FIG. 7 is a diagram showing the internal details of the block processing circuit 409 shown in FIG.

701, 702, 703, ..., 704, 7
Reference numeral 15 is a D flip-flop (hereinafter referred to as DFF), which is arranged in series with 15 pieces, and uses an input signal as a pixel clock CLK.
The signals are sequentially delayed, and VE = "0", that is, cleared to "0" in the non-image section.

Reference numeral 738 is a 5-bit up / down counter, 737 is an OR gate, and 740 is an AND gate. The operation is based on the following display.

[0039]

[Table 1]

That is, the output of the counter 738 is VSY.
NC or VE is cleared to 0 in the section of "0", X _t =
Held at the time of X _t-15, at the time of X _t = 1 and X _t-15 = counts are up X _t = 0 and X _t-15 = 1 when 0 is counted down.

[0041] In other words, as a result, 16 of the X _t ~X _t-15
The total sum (the number of = 1) of the data is output.

Further, the output is passed through the DFF 739 to 1
Line-in first in first out
Memory (FIFO) 721, 722, 723, ..., 73
Data of 16 lines are simultaneously input to the adder 741 by 4,735, and the total sum is output. As a result, the sum SUM of the numbers of 1's in the 16 × 16 window
Is output from 0 to 256.

Reference numeral 742 is a digital comparator,
The output SUM of the adder 741 is compared with the comparison value TW predetermined by the CPU 417, and the result is output as "0" or "1".

Therefore, noise can be removed in 16 × 16 block units by setting an appropriate value in TW in advance.

FIG. 8 is a diagram for explaining the watermark detection circuit 410.

819, 820, ..., 821 are 18 Fs.
IFOs, each with a delay of 1 line, 19 lines being processed simultaneously.

801, 802, 803, ..., 804, 8
05,806,807, ..., 808, ..., 809,81
0, 811, ..., 812, ..., 813, 814, 81
Numerals 5, ..., 816 are DFFs arranged in series for each of the outputs of 19 lines, and numeral 817, 8
Reference numeral 18 is a DFF further arranged in 9-series after the DFF 812, and all DFFs are driven by CLK16. D via AND gates 823, 824, 825
, 812, 816 (19 vertical blocks) and DFFs 809, 810, 811, 812 and FFs 804, 808 ,.
When all the outputs of 817 and 818 (horizontal 19 blocks) are "1", 1 is output, and Pos at that time is output.
Ition is latched and sent to the CPU.

FIG. 9 is a block diagram of the address decoder 414.

901, 902, 903, 904, 90
Reference numerals 5, 906, 907, 908, and 909 are registers connected to the data bus of the CPU, and a desired value is written by the CPU.

Since all of 910, 911, 912, and 913 have the same structure, only 910 will be described.

914 and 915 are subtractors, which have inputs A,
AB is output for B, the output MSB is a sign bit, and when it becomes negative, MSB = 1 is output.

Reference numerals 916 and 917 denote comparators which output "1" when A <B with respect to inputs A and B. However, when the MSB of A is "1", "0" is output regardless of the input of B.

ANDs 918, 919 and 920 respectively
When it is a gate and the value BXY is written in the register 909 as a result

[0054]

[Outside 1] Only when

[0055]

[Outside 2] Is output.

Similarly, at 911

[0057]

[Outside 3] Only when, the output of X2 = X address-RX2 Y2 = Y address-RY2 E2 = 1 is output.

Similarly, at 912

[0059]

[Outside 4] Only in the case of, the output of X3 = X address-RX3 Y3 = Y address-RY3 E3 = 1 is output.

Similarly, at 913

[0061]

[Outside 5] Only when, the output of X4 = X address-RX4 Y4 = Y address-RY4 E4 = 1 is output.

914, 915, 916, 917, 918
Are OR gates, and conditions (1), (2),
RX (3) and (4) should not be established at the same time.
1, RY1, ... RX4, RY4 are set, any one of X1, X2, ... X4 is output from 914, and “1” is output from 917 when any of the conditions is satisfied. From 918, Y1, Y2 ... Y
Any one of 4 is output.

The outputs from 915 and 916 are as shown in the following table.

[0064]

[Table 2]

(Processing Flow) FIG. 3 shows four scans from the first scan to the fourth scan in this apparatus, four modes from mode 1 to mode 4 in the image scanner, and the printer section. Indicates the output content.

FIG. 10 shows a processing flow under CPU control. In FIG. 10, at 1001, the CPU sets the mode 1 for the first scan. In mode 1, the printer outputs magenta and detects the rough position of the watermark portion in the bill. Therefore, in the window comparator 408, the CPU writes in the registers 601 to 606 shown in FIG. 6 a value with which the background of the bill can be detected.

In this state, at 1002, the first scan is started.

FIG. 1 shows a state where a 10,000-yen bill is placed on the platen. In the first scan, that is, in mode 1, the output of the window comparator is the shaded portion in FIG. 1, that is, the watermark and the surrounding area. It becomes "1" in the part.

Further, in the watermark portion, since this continues for a certain number of pixels in the vertical / horizontal direction, (Xc, Yc) in FIG.
In the detection circuit 410, the part corresponding to
The addresses for c, Yc) are latched and sent to the CPU.

The CPU can roughly know the value of (Xc, Yc) which is the center of the bill.

Next, in FIG. 10, the setting for mode 2 is performed at 1003. That is, in mode 2, the selector 411 is set to A, and the selectors 413 and 41 are
5, 416 are set to the A side, and the address decoder 41
In 4,

[0072]

[Outside 6] The value of RX2 = RX3 = RX4 = RY2 = RY3 = RY4 = 0 is written in advance.

At this time, in the second scan of 1004, if T is set to a value corresponding to about 128 mm in the RAM 412, only the shaded portion is "1" in the broken portion. It is possible to obtain various bitmaps. The 128 mm is set as a numerical value such that the bill is included inside the broken line shown in FIG. 1 regardless of the type of bill and the angle at which it is placed.

Further, the CPU 417 detects the accurate position and angle of the bill at 1005 from this bitmap.
At that time, the CPU selects the selector 411 to C and 413 to B, and freely reads the RAM 412. Figure 10
The principle is shown in, but the method of detecting the four corners around the bill is adopted. That is, when placed as shown in FIG. 11, of the part that is 1 in the bitmap,

[0075]

[Outside 7] Also,

[0076]

[Outside 8] By utilizing that, four corners are detected.

Although detailed description is omitted, four corners can be detected at any angle by using either condition (5) or (6).

Therefore, in FIG.

[0079]

[Outside 9] The angle θ is also calculated in the following equation.

Further, the position of the red stamp is calculated from the obtained angle and position. Since the banknotes are placed face up, face down, or on the back / front, (X _S1 ,
Y _S1 ), (X _S2 , Y _S2 ), (X _S3 , Y _S3 ), (X _S4 , Y
_{One of S4} ) is the position of the red stamp. These are calculated by (X ₀ , Y ₀ ), θ by a simple calculation.

Next, in step 1006, mode 3 for 3rd scan is set. That is, the selector 411 is set to B, the selector 413 is set to A, and the selectors 415 and 416 are set to B.

In the address decoder 414, the position of the red mark is RX ₁ = X _S1 RY ₁ = Y _S1 RX ₂ = X _S2 RY ₂ = Y _S2 RX ₃ = X _S3 RY ₃ = Y _S3 RX ₄ = X _S4 RY ₄ = Y _S4 (one pixel unit), and the number of pixels corresponding to about 30 mm that sufficiently covers the red mark in FIG. 1 is set in BXY.

Next, a value is set in each register in the window comparator 408 shown in FIG. 4 so that 1 is output only for the red portion of the red mark.

Next, at 1007, the third scan is performed, and the output of the window comparator 408 is output to the RAM 41 at four positions which are considered to be the positions marked with red in FIG.
Written to 2.

Further, a red stamp is extracted by the algorithm described later in 1008 and judged in 1009. If there is no possibility of forgery, that is, if the red stamp is not detected, 4th scanning is performed in 1010 and normal operation is performed. Then, it is developed with four color toners of Y, M, C and Bk, and is fixed and output at 1012.

On the other hand, in 1009, when it is determined that there is a possibility of forgery, that is, when a red stamp is detected,
Forgery prevention and the like are taken in 1011. In particular,
Set FF _H in the register of FIG 4408 (usually OO _H is set) by, FF _H is to the printer unit
Is sent, Bk toner adheres to the entire surface, and copying cannot be performed.

(Pattern Matching) Next, the pattern matching of red stamp 1008 will be described in detail.

Since the red stamp of the bill is different between the front and back, 1
In order to discriminate between types of banknotes, two red stamp patterns are registered in advance when performing pattern matching.

When the specific portion of the specific original is written in the RAM 412, the CPU 417 then refers to the contents of the RAM 412 to perform the pattern matching operation. A flow chart of pattern matching is shown in FIG. Four kinds of binarized data are stored in the RAM 412 as candidates for the specific portion. This is named area 1 to area 4.

First, the processing after 2102 is performed on area 1. At 2102, window processing for noise removal is performed.

Assume that the binary image of area 1 is 2201. Here, it is assumed that a small square represents one pixel, a blank pixel is a white pixel, and a shaded portion is a black pixel. 22 this
Scanning is performed in a window of 2 × 2 pixels indicated by 02, black pixels in the window are counted, and a portion where the count value exceeds 2 is newly set as a black pixel. By doing so, the processing result is reduced to 1/2 in each of the vertical and horizontal directions, as shown by 2203, and a noise-removed pattern is obtained. Since the number of black pixels in the window at the position of 2202 is 1, it has been changed to the position of 2204 as a white pixel.

Next, the barycentric position of the pattern 2203 is calculated.

This can be calculated by a known method by projecting the pattern 2203 in the vertical direction and the horizontal direction.

Next, the degree of similarity is calculated by standard pattern matching. First, the standard pattern registered in advance as a dictionary in 2105 is read from the ROM 418 of FIG.
Look into the PU. The standard pattern is the red stamp pattern of the current banknote, but the patterns extracted up to 2103 may be rotated depending on the angle at which the banknote is placed on the platen. Satisfactory results cannot be obtained even when compared with the pattern.

This state is shown in FIG. Therefore, as the standard pattern, a plurality of patterns obtained by rotating the red stamp pattern every several degrees may be created and stored in the ROM in advance, and an appropriate pattern may be selected from these to be read into the CPU. As a plurality of patterns, for example, a total of 24 patterns in which red stamps are rotated at intervals of 15 degrees from 0 degree to 360 degrees are used, and as a selection method, the angle θ on which a banknote that has already been detected is referred to. , -8
When ≦ θ <8 degrees, the standard pattern of rotation angle φ degrees, 8 ≦
When θ ≦ 24 degrees, a pattern with a rotation angle of 15 degrees, 24 ≦
When θ <40 degrees, the similarity calculation can be executed with sufficient accuracy by performing a pattern with a rotation angle of 30 degrees.

Here, since there is obviously an uncertain amount of 180 degrees between the rotation angle θ of the banknote and the rotation angle of the red stamp, when the standard pattern of the rotation angle φ is actually selected, the rotation angle is It is also necessary to select the standard pattern of 180 degrees, and also to select 195 degrees for 15 degrees and 210 degrees for 30 degrees at the same time. Therefore, similarity calculation is always performed twice. Become.

Next, various methods can be considered for calculating the degree of similarity in step 2106. For example, the following method can be considered. As shown in FIG. 15, the pattern extracted up to the above is defined as (a) or the standard pattern having a predetermined rotation angle selected by the above method is defined as (b), and B (i, j) and P (i, j) are respectively defined. ). (B (i, j) and P (i, j) have a value of 1 for black pixels and φ for white pixels)
The barycentric coordinates of B (i, j) obtained in (i _BC ,
j _BC ), and the barycentric coordinates of P (i, j) obtained in the same manner as (i _PC , j _PC ), the similarity COR between the two is given by the following equation.

[0098]

[Outside 10] Expression (1) is obtained by pattern B (i, j) and pattern P (i, j).
j) represents the Hamming distance when the centers of gravity are aligned. The greater the COR, the greater the similarity between the two.

In this embodiment, the similarity COR is obtained by using the equation (2) which is a modification of the equation (1) in order to improve the reliability of the similarity and suppress the occurrence of erroneous recognition as much as possible.

[0100]

[Outside 11] When both P and B are black pixels, 2 is added to COR, P = 0,
When B = 1, 1 is subtracted from COR, and the recognition accuracy can be greatly improved.

When the similarity COR is calculated as described above, 2
At 107, the threshold Th obtained in advance is compared with COR.

When COR> Th, it is determined that a red stamp exists, it is determined that there is a banknote (2108), and the collating operation ends.

When COR <Th, it means that the red stamp does not exist in the current processing area. When n is smaller than 4, n is incremented by 1 and 2 is added to the next area n.
The collating operations 101 to 2109 are repeated. 2109 in n
= 4, it means that there is no red stamp pattern in any of the first to fourth areas, and there is no banknote (2
As a result of 110), the matching operation ends.

(Other Embodiments) This specification has described the prevention of counterfeiting of Japanese banknotes of 10,000-yen bills, but its application range is wide and a relatively wide background and characteristic patterns such as red stamps and patterns are used. If included, it can be easily applied to securities, other national tickets, newly revised tickets, and the like.

Further, the present invention is not limited to the electrophotographic copying machine, and is also important as a simple image scanner or as an additional function of the printer alone.

In the present embodiment, the size and position of the document placed on the document table are determined before the pattern matching with the pattern registered in advance is performed. Even in a device in which the document is sequentially sent to the reader unit having a sensor, the document may be reciprocated with respect to the reader unit so that the same document can be scanned several times.

As described above, according to the present embodiment, the position and the angle of a bill or the like are detected by the background portion, the red mark is detected, and the pattern matching is performed, whereby the position and the angle are set. It is possible to prevent forgery of bills and the like.

[0108]

According to the present invention, when the first color component signal is generated in the plurality of scans for generating the plurality of color components based on the target image of the color image processing apparatus, the first identification reference is used. It is used to identify whether or not the target image is the predetermined image, and when the second color component signal is generated, the target image is determined to be the predetermined image by using a second identification criterion different from the first identification criterion. Since it is discriminated whether or not it is an image, it is possible to perform discrimination using different discrimination criteria, and it is possible to reduce the load of the recognition processing that occurs when the recognition processing is performed using the image signal obtained by one scanning.

[Brief description of drawings]

FIG. 1 is a diagram showing banknotes placed on a document table.

FIG. 2 is a schematic view of an apparatus according to this embodiment.

FIG. 3 is a diagram showing a relationship between four scans and each mode.

FIG. 4 is a block diagram of an image scanner.

FIG. 5 is a timing diagram.

6 is a block diagram of the window comparator shown in FIG. 4. FIG.

FIG. 7 is a diagram of a block processing unit shown in FIG.

FIG. 8 is a diagram of the watermark detection unit shown in FIG.

9 is a diagram of the address decoder shown in FIG. 4. FIG.

FIG. 10 is a flowchart showing the operation of the apparatus.

FIG. 11 is a principle diagram of position detection.

FIG. 12 is a diagram illustrating pattern matching.

FIG. 13 is a diagram illustrating pattern matching.

FIG. 14 is a diagram illustrating pattern matching.

FIG. 15 is a diagram illustrating pattern matching.

[Explanation of symbols]

 210-1 to 210-3 CCD 408 Wind comparator 412 RAM 417 CPU

Claims (3)

[Claims] 1. A predetermined one of a plurality of scans of a target image
Scanning means for generating a first color component signal during one scanning and generating a second color component signal during another scanning other than the predetermined one scanning. Generation of a first color component signal for the scanning means. At this time, a first identification means for identifying whether or not the target image is a predetermined image using a first identification criterion, and a second identification signal for generating the second color component signal of the scanning means. And a second identifying means for identifying whether or not the target image is the predetermined image using a different second identification criterion. 2. The image reading apparatus according to claim 1, wherein the scanning unit is composed of a CCD line sensor. 3. The image reading device according to claim 1, wherein the predetermined image is a banknote.