JPH087108A - Image processor - Google Patents

Abstract

PURPOSE:To simplify the configuration of the device and to enable efficient processing in the case of recognizing any specified pattern and performing processing corresponding to the recognized result at the image processor for handling electric image signals. CONSTITUTION:When a scanning optical system equipped with a light source 103 and a CCD line sensor 105 or the like reads the images of a color original 101 and converts them to signals in C, M and Y by performing prescribed processing based on those images, any one of these signals selected by a selector 112 is outputted and the image in the selected color is outputted by an output part equipped with a semiconductor laser 118, photosensitive drum 121 and developer 122. When performing such reading and successively outputting images corresponding to C, M and Y, a recognizing circuit 127 recognizes whether the specified pattern is contained in the read data or not parallelly with the respective image outputs.

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,
In particular, the present invention relates to an image processing apparatus having a function of recognizing whether or not a document contains a predetermined specific pattern.

[0002]

2. Description of the Related Art In recent years, high-performance color image copying machines have begun to spread, and it is expected that crimes such as forgery of banknotes and securities using the color image copying machine will frequently occur. . Therefore, when a color original is digitally read and copied, a read signal is used to identify a specific pattern in the original, and when the identified pattern is recognized as a bill or the like, a copying operation is performed. Has been proposed (Japanese Patent Laid-Open No. 55-111).
(See No. 977).

[0003]

However, conventionally, it has not been considered that an image processing apparatus that handles an electrical image signal performs the above-described identification and controls the apparatus according to the recognition result. .

Therefore, no rational configuration and efficient processing procedure have been considered for constructing such an apparatus.

Therefore, according to the present invention, in an image processing apparatus which handles an electrical image signal, when recognizing a specific pattern and performing control according to the recognition result, the structure of the apparatus is simplified and efficient processing is performed. It is an object of the present invention to provide an image processing device capable of performing.

[0006]

In order to achieve the above object, the present invention provides an input means for inputting an electrical image signal representing a document, and processing the electrical image signal input by the input means. In an image processing apparatus having a processing means for outputting a processed electric image signal, whether an original represented by the electric image signal includes a specific pattern based on the electric image signal input by the input means. A recognition means for recognizing whether or not there is a recognition means; and a control means for controlling the device according to a recognition result of the specific pattern in the document by the recognition means, wherein the processing means and the recognition means respectively perform processing and The feature is that recognition is performed in parallel.

[0007]

According to the above construction, in the image processing apparatus which handles an electrical image signal, when the specific pattern is recognized and the control is performed according to the recognition result, the processing of outputting the electrical image signal and the specific pattern are performed. Since the recognition is performed in parallel, the configuration of the device can be simplified and efficient processing can be performed.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a circuit configuration of an embodiment of the present invention applied to a color image copying apparatus using a laser beam printer.

In the figure, reference numeral 101 denotes a color original to be copied, which is placed on the original placing table glass 102. 103 is a light source for illuminating the original 101, and 104 is a CCD for the reflected light (original image) from the original illuminated by the light source 103.
It is a converging rod lens array that forms an image on a line sensor. In the CCD line sensor 105, red (R), green (G), and blue (B) filters are alternately coated on the lines, and the original image is separated into three primary colors and converted into electric signals. The above-mentioned documents 103 to 105 are housed in a reading head (carriage) and integrally scanned by a scanning mechanism (not shown) in the direction of the arrow (sub-scanning direction) in FIG.
Scan the image of.

Reference numeral 106 denotes a sample hold of an analog electric signal (image signal) from the line sensor 105, and R,
A sample and hold circuit for converting the G and B time series signals, 107 is an A / D (analog / digital) converter for analog / digital conversion of the output signal from the sample and hold circuit 106, and 108 is a CCD line sensor 105. CC
This is a shading correction circuit that corrects the variation in sensitivity of the D1 line and the uneven illumination. 109 represents the R, G, B signals corrected by the shading correction circuit 108 in cyan (C),
A logarithmic conversion circuit for converting to complementary color density signals of magenta (M) and yellow (Y), 110 extracts the minimum value of the C, M, Y signals output from the logarithmic conversion circuit 109, and black (K, black) It is an inking circuit that generates a signal and a UCR circuit that subtracts a portion corresponding to the K signal from the Y, M, and C signals.
111 is a masking circuit for correcting unnecessary absorption of the output side color material, and 112 is Y, M, C, obtained as described above.
It is a selector circuit for selecting a signal to be sent to the printer section (a laser beam printer in the case of this example) among the K signals.

Reference numeral 113 is a gate circuit for turning on / off the output from the selector 112 for outputting to the printer in accordance with a control signal from a CPU (Central Processing Unit) 128, which will be described later. Reference numeral 114 denotes a D / A (digital-analog) converter that converts a digital signal sent from the image reading section via the gate circuit 113 into an analog signal. D /
The output of the A converter 114 is compared with a triangular wave signal of a predetermined cycle generated from the triangular wave generator 115 by a comparator 116,
Pulse width modulation (PWM) with a pulse width proportional to the image signal
The signal is obtained from the comparator 116. This PWM signal is applied to the semiconductor laser 118 via the laser driver 117.

The emission beam of the semiconductor laser 118 is P
Polygon mirror modulated by WM signal and rotating at high speed
Photosensitive drum 12 rotating via 119 and folding mirror 120
1 Reach above (see broken line in this figure).

The photosensitive drum 12 is irradiated with a laser beam.
The electrostatic latent image formed on 1 is surface-sequentially developed in the order of C, M, Y, and K by the rotary developing device 122 and recorded as toner images of respective colors. This toner image is sequentially transferred onto the transfer paper 124 on the transfer drum 123 in the order of C, M, Y and K. The transfer paper 124 is conveyed from a paper cassette (not shown) and wound around the transfer drum 123, and C, M,
When the transfer of Y and K four times is completed, the sheet is discharged to the discharge side conveying path 125, heat-fixed by the fixing device 126, and discharged to the outside as a final copy image.

A recognition circuit 127 identifies whether or not the pattern on the document 101 is a specific pattern.
Controlled by.

In the above-mentioned structure, it is necessary to scan and read the original 101 four times in synchronism with the C, M, Y and K outputs of the printer, and the selector 112 outputs corresponding to each scanning. Switch the signal to the printer C or M
Alternatively, a signal corresponding to Y or K is transmitted. Therefore, in the present embodiment, the recognition circuit 127 is operated by different algorithms according to the document scanning operation of a plurality of times, and the accuracy of recognition of the specific pattern is improved by comprehensively judging the recognition result. .

Next, referring to FIG. 2, the recognition circuit 12 described above is used.
The operation of 7 will be described in detail. FIG. 2 shows a detailed circuit configuration inside the recognition circuit 127. The R, G, and B signals from the shading correction circuit 108 shown in FIG. 1 are binarized by comparators 201 to 203 at predetermined threshold values. An AND circuit 205 takes the logical product of these binarized results, and "1" is output only for pixels that exceed the threshold values for all R, G, and B.

Reference numeral 206 denotes an edge point detection circuit for detecting an edge point of an original image. For example, as shown in FIG. 3, when a bill 302 is placed as the original 101 on the original placing table glass 102, the bill 302 The edge point on one side (point on the straight line 303) is detected. 207 indicates a bill 302 based on the detection result of the edge detection circuit 206.
3 is an angle detection circuit for detecting the rotation angle θ (see FIG. 3). Reference numeral 208 denotes a part of the input document image (for example, a hatched portion indicated by 304 in FIG. 3) based on the detection result θ of the angle detection circuit 207.
Is an affine transformation circuit that cuts out, rotates by (−θ), and writes it in the memory 209.

With the above-mentioned configuration, the memory 209 has a structure shown in FIG.
The image of the cut-out portion 304 of is written in a non-rotated state. On the other hand, a regular image pattern corresponding to the cutout portion 304 is written in the memory 210 from the CPU 128. Next, the contents of the memory 209 and the contents of the memory 210 are superposed by the matching circuit 211, and the correlation value thereof is obtained. The correlation value obtained by the matching circuit 211 is output to the CPU 128 again, and the CPU 128 determines based on the correlation value whether or not the input image matches the regular image pattern (hereinafter referred to as the regular pattern). It

In the above operation, the angle detection in the angle detection circuit 207 has an indefiniteness of ± 180 degrees,
Only one matching calculation will not make a correct decision for an image that has been flipped 180 degrees. Therefore, in this embodiment, in the first document scanning, the memory 210
If an upright normal pattern is written in and the inverted (180 ° inverted) normal pattern is written in the second scan of the document, the 180 degree indeterminacy can be resolved by two scan and recognition operations. become. That is, in FIG. 1, the first scan / recognition is associated with the cyan image output, the second scan / recognition is associated with the magenta image, and either one of the two recognition results is obtained. If it is determined that the pattern matches with the regular pattern, the CPU 128 immediately turns off the gate circuit 113 and terminates the output of the image signal to the printer. By doing so, at least the yellow image and the black image are not written on the photosensitive drum 121, so that the copy image output on the transfer paper can be clearly distinguished from the input document, and is not suitable for the purpose of forgery. It will be.

Next, a second embodiment of the present invention will be described with reference to FIG. In the present example, the above-mentioned indeterminacy of 180 degrees can be solved at once by having two circuits having the configuration shown in FIG. Furthermore, the read density is changed between the first scanning and the second scanning. That is, in the first read scan, the image decimated by the affine transformation circuit 208 every other pixel is written in the memory 209, and in the second read scan, the image is written in the memory 209 as it is without decimating the read density. To do. A normal pattern corresponding to each density is written and stored in the memory 210. By doing so, even if a sufficient correlation value cannot be obtained only by the first matching, the CPU 128 can determine that it matches the regular pattern if a high correlation value is obtained by the second matching. You can

In addition, various other embodiments such as the following are possible.

The comparator of FIG. 2 for the first and second scans
Change the threshold value given to 201-203.

The memory of FIG. 2 for the first and second scans
The image to be written in 209 is shifted by a few pixels to absorb the misalignment between the input pattern and the regular pattern.

The memory of FIG. 2 for the first and second scans
Change the regular pattern written in 210. For example, 1
In the second scanning, the pattern of 10,000 yen bills is changed, and in the second scanning, the pattern of 1,000 yen bills is changed.

Of course, the number of scans is not limited to two in the above. Further, the number of scans is not limited to 4 times or less. For example, when it is determined that the pattern is close to the regular pattern during the scanning of 4 times or less, the transfer paper is not discharged from the transfer drum 123 and only the original is scanned. It is also possible to carry out the recognition process and continue the recognition process, and at the time when it finally coincides with the regular pattern, the fifth transfer is performed, and at that time, the entire copy image is painted.

Next, a third embodiment of the present invention will be described. In the present embodiment, the image output is not performed in the recognition process in the first scanning, and if it is determined that the document is close to the regular pattern such as a bill in this process, the scanning is stopped at that time. If it is not determined that the pattern is close to the regular pattern, the image is continuously read four times corresponding to C, M, Y, and K and the image signal is output to the printer to output a copied image.

When the scanning is stopped, a message is outputted from the CPU 128 to the liquid crystal display or the like 130 so as to prompt the operator to reposition the original, and to prompt the operator to restart. When the restart is instructed by the operator with the key 131, the above-described recognition and copying process is restarted again.

By doing so, it becomes possible to eliminate the recognition failure due to a slight positional deviation of the document, an angular error, and the like.

[0030]

As described above, according to the present invention,
In an image processing device that handles electrical image signals, when recognizing a specific pattern and performing control according to the recognition result,
Since the process of outputting the electrical image signal and the recognition of the specific pattern are performed in parallel, the configuration of the device can be simplified and efficient processing can be performed.

In particular, the apparatus can be appropriately controlled to prohibit the faithful reproduction of the original image, for example, changing the image formation of a specific color component or stopping the reading scan.

[Brief description of drawings]

FIG. 1 is a block diagram showing a circuit configuration of an embodiment of the present invention.

FIG. 2 is a block diagram showing a circuit configuration of a recognition circuit of FIG.

FIG. 3 is a plan view showing a state during reading and scanning of an input document.

[Explanation of symbols]

 101 Color original 102 Original platen glass 103 Light source 104 Lens 105 CCD line sensor 106 Sample hold circuit 107 A / D converter 108 Shading correction circuit 113 Gate circuit 127 Recognition circuit 128 CPU 201 to 203 Comparator 204 Threshold setting circuit 206 Edge detection circuit 207 Angle detection circuit 208 Affine conversion circuit 209,210 Memory 211 Matching circuit

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Claims (1)

[Claims] 1. An image having input means for inputting an electrical image signal representing a document, and processing means for processing the electrical image signal input by the input means and outputting the processed electrical image signal. In the processing device, based on the electric image signal input by the input unit, a recognition unit that recognizes whether or not the document represented by the electric image signal includes a specific pattern; And a control unit that controls the device according to the recognition result of the specific pattern, wherein the processing unit and the recognition unit perform processing and recognition in parallel, respectively.