JP3347371B2 - Image processing method - Google Patents

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, for example, an image processing apparatus having a function of detecting a specific document.

[0002]

2. Description of the Related Art Conventionally, with the improvement of image quality, colorization, and spread of image processing apparatuses, specific originals (for example, securities / banknotes / confidential documents) that should not be processed are hardly distinguished from originals. There is a risk that it will be duplicated with high image quality and abused. For this reason, in a device such as a full-color copying machine that outputs a read image signal in real time, the read image data is compared with the image data of a specific document every multiple document scans, and a latent image is formed during the next document scan. Attempts have been made to add a specific pattern to the pattern.

[0003]

However, as described above,
In an image input device having no latent image formation,
Copy protection processing cannot be performed. The present invention has been made in view of the above points.
It was done .

[0004]

Means for Solving the Problems The above-mentioned problems are solved,
In order to achieve the object, the image processing method according to the present invention is an image processing method.
Color image from image signal output side device to image signal input side device
An image processing method that transfers signals and duplicates images.
In the image signal output side device, the color-separated color
A first output for outputting an image signal to the image signal input side device;
Force step, the image represented by the color image signal and the specific image
After the start of the output of the color image signal
The determination signal indicating the determination result is transmitted to the image signal input side device.
A second output step of outputting to the image signal input
The side device, the color from the image signal output side device
A first input step of inputting an image signal, and the color image
Subsequent to the input of the signal, the image signal output side device
A second input step of inputting the determination signal;
If the number indicates that there is a specific image, the input color image
Invalidating the signal .

[0005]

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In the following embodiments, an example of a copying machine will be described as an application example of the present invention. However, the present invention is not limited to this, and it is needless to say that the present invention can be applied to various other apparatuses. Each device to which the present invention can be applied is:
To prevent counterfeiting, specific documents such as banknotes and securities are symmetric.

(First Embodiment) FIG. 2 is a side sectional view showing a schematic internal structure of an image scanner main body according to a first embodiment of the present invention. In FIG. 2, reference numeral 201 denotes an image scanner unit which reads an original at a resolution of 400 dpi and performs digital signal processing. In the image scanner unit 201, 200 is a mirror surface pressure plate,
A document 204 on a platen glass (hereinafter, referred to as a “platen”) 203 is irradiated by a lamp 205,
The light is guided to lenses 207 and 208, and forms an image on a three-line sensor (hereinafter referred to as “CCD”) 210 by a lens 209. Sent. In addition,
The speed of the carriage 227 fixing the ramp 205 and the mirror 206 is v, and the speed of the mirrors 207 and 208 is １ ／.
The entire surface of the document is scanned (sub-scanning) by mechanically moving the line sensor in the direction perpendicular to the electrical scanning (main scanning) direction of the line sensor at v.

The signal processing section 211 electrically processes the read image signals (RGB signals), outputs the processed signals to the outside, and compares the read image signals with specific image signals. [Image Scanner Unit] FIG. 1 is a block diagram showing a circuit configuration of an image scanner unit 201 according to the first embodiment. In the figure, 210-1, 210-2, 210-
Numerals 3 denote CCD (solid-state imaging device) line sensors having spectral sensitivity characteristics of red (R), green (G), and blue (B), respectively, each having an 8-bit output of 0 to 255 after A / D conversion. Output a signal. 401, 402
Is a delay element.

The CCD line sensors 210-1, 210-2, and 210-3 used in this embodiment are arranged at a fixed distance from each other.
At 402 and 402, the spatial shift is corrected. 4
Reference numerals 03, 404, and 405 denote log converters, each of which is configured by a look-up table ROM or RAM, and converts a luminance signal into a density signal.

Reference numeral 409 denotes a circuit for determining a specific document. Here, the specific document determination circuit 409 determines whether the document placed on the platen is at least one of the plurality of specific documents, and outputs a determination signal H in multi-valued 2-bit. That is, when it is most likely that at least one of the plurality of specific originals is being read, H =
"3" is output, and when the possibility is the least, H
= “0” is output. The determination signal H indicates that it is more likely that at least one of the plurality of specific originals is being read from “0” to “3”.

Reference numeral 408 denotes an output control unit.
The RGB signal is output to the outside according to the determination signal H from the control signal 9. [Judgment Circuit] FIG. 3 shows a judgment circuit 409 according to the first embodiment.
FIG. 3 is a block diagram showing the configuration of FIG. Referring to FIG.
Is a thinning circuit as shown in FIG.
In order to reduce the addition of the processing circuit 09, processing for thinning out data is executed. Reference numeral 302 denotes a color matching look-up table ROM (hereinafter, referred to as “LUT”) which stores the color of a read document image and a plurality of types of specific documents prepared in advance (securities, bills, confidential documents, etc.). Perform matching. In the LUT 302, the color distribution of the eight specific documents is checked in advance, and the color of the pixel is determined as follows.
The determination result of whether or not the color matches the color of the specific document is held.

That is, in the LUT 302, the upper 5 bits of the RGB image signal of each color thinned out to the lower 15 bits of the address.
Each bit is input. The color of the pixel is 8
Whether or not the color matches the type of the specific original is simultaneously output in association with the 8-bit data, and a total of eight types of determinations are made in one reading scan.

303-1, 303-2,..., 303-8
Is a color determination circuit composed of the same hardware, and includes an integrator 306, registers 307-1 and 307.
-2, 307-3, and a comparison module 308, each of which determines the possibility that a specific document exists in the document, and outputs the determination result in two bits. Reference numeral 309 denotes a maximum value circuit which outputs the maximum value among the determination result outputs of the tint determination circuits 303-1 to 303-8. That is, the determination result corresponding to the specific document most likely to exist among the eight types of specific documents is output.

[Timing Chart] FIG. 4 is a circuit diagram showing a configuration of a thinning circuit according to the first embodiment, and FIG. 5 is a circuit diagram showing a configuration of a frequency dividing circuit according to the first embodiment. FIG. 7 is a timing chart in the main scanning direction in the first embodiment. In FIG. 7, VSYNC
The signal is a sub-scanning section signal, and is a signal indicating a sub-scanning image output section. HSYNC is a main scanning synchronization signal and is a signal for synchronizing the start of main scanning. CLK is an image transfer clock, and is a basic clock for various image processing in this embodiment.

On the other hand, CLK ′ is obtained by dividing CLK by １ ／ and becomes a basic clock in the determination circuit 409. The SEL signal is a timing signal used in the thinning circuit 301 described later. The CLK 'and SEL signals are respectively generated by a frequency dividing circuit 310 as shown in FIG. In FIG. 5, the frequency dividing circuit 310 includes an inverter 45
1, 2-bit counter 452, inverter 453, AN
It comprises a D gate 454. 2-bit counter 45
2, after being cleared (initialized) by an HSYNC signal which is a main scanning synchronization signal, counts CLK and outputs the count value in two bits (D0, D1). The upper bit D1 is output as CLK 'and the lower bit D1 is output.
The logical product of the inverted signal of 0 and the upper bit D1 is output as the SEL signal.

Referring to FIG. 4, a thinning circuit 301 includes:
Flip-flops 455, 4 holding data at CLK
56, 457, 461, 462, 463, selectors 458, 459, 460 for switching by SEL signal, CL
Flip-flops 464 and 46 holding data at K '
5,466. The thinning circuit 301 is shown in FIG.
As shown in R, R (or G,
B) The signal is thinned out at a rate of 1/4 from the signal and CLK '
R ′ (or G ′, B ′) signal synchronized with the above can be obtained.

[Integrator] FIG. 6 is a block diagram showing the structure of the integrator 306 according to the first embodiment.
FIG. 5 is a diagram showing input and output of the integrator 306 according to the first embodiment. In FIG. 6, reference numerals 501 and 505 denote flip-flops which hold data at the rising timing of CLK '. Reference numeral 502 denotes a multiplier that receives an 8-bit 2-input signal (A, B) and outputs an 8-bit signal (A × B / 255) as a multiplication result. A multiplier 503 receives a 1-bit input signal (A) and an 8-bit input signal (B), and outputs an 8-bit output signal (A) as a multiplier.
× B) is output. An adder 504 receives two 8-bit input signals (A, B) and outputs an 8-bit signal (A + B) as an addition result.

As a result, in the integrator 306,
For a binary input signal x _i , an 8-bit output signal y _i is
It is represented by the following equation (1). That is, y _i = (α / 255) y _i−1 + β · x _i−1 (1) where α and β are preset constants,
Various characteristics of the integrator 306 are determined by the magnitudes of these values.

For example, when α = 247 and β = 8, an output y _i as shown in FIG. 9 is output for an input x _i as shown in FIG. Here, 701, 70
As shown by the point 2, an input in which the surrounding is almost “0” but “1”, or as shown by the point 703,
An input that is "0" despite its surroundings being almost "1" is considered to be noise. This is processed by the integrator 306 and the register 307 of FIG.
-1 (R1), 307-2 (R2), 307-3 (R
By setting an appropriate threshold such as 3) and binarizing the output y _i of the integrator with this, noise (noise) can be removed.

[Comparator Module] FIG. 10 is a block diagram showing the configuration of the comparator module 310 according to the first embodiment. In the figure, 801, 802, and 803 are comparators, 804 is an inverter, 805 is an AND gate, and 806 and 807 are OR gates. The register 307-1 has R1 in advance, the register 307-2 has R2,
A threshold value of R3 is set in the register 307-3. These threshold values have a relationship of R1>R2> R3.

With this configuration, as a result, the determination result is quantized into two bits and output. That is, if R1 <(input), 11 (binary) is output; if R2 <(input) ≦ R1, 10 (binary) is output; if R3 <(input) ≦ R2, 01 (binary) is output. Binary) is output. If (Input) ≦ R3, 00 (binary) is output.

[Output Control] FIG. 11 is a block diagram showing the configuration of the output control unit 408 according to the first embodiment. In the figure, 1101-1 to 1101-6 are inverters,
1102-1 to 1102-6 are AND gates, 1103
Reference numerals -1 to 1103-3 and 1104 indicate OR gates, respectively.

According to the above configuration, the output control unit 408
Is the 8-bit RG from the log converters 403-405.
The output RGB signal is controlled by the B signal and the 2-bit determination signal H from the determination circuit 409. In this embodiment, if the judgment signal is "0", the RGB signal is output through, if the judgment signal is "1", the G signal and the B signal are inverted, and if the judgment signal is "2", the R signal is outputted. The B signal is inverted, and if the determination signal is "3", the R signal, the G signal, and the B signal are all inverted and output.

As described above, according to the first embodiment, in an image processing apparatus that outputs a full-color image signal in one original scan, comparison with a specific image signal is performed during original scan, and as a result, By controlling the subsequent processing according to the above, it is possible to prevent abuse due to duplication of a specific document or the like. Second Embodiment In the first embodiment, RGB signals (image signals) have already been output before the first determination (determination of a specific document) is performed. By having the function of storing the RGB signals required for the determination, it is possible to output the RGB signals after the first determination is made.

FIG. 12 is a block diagram showing the configuration of the image scanner unit according to the second embodiment. The same circuits as those in FIG. 1 described in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. In FIG. 12, 1401
Is a storage unit, and 8 from the log converters 403 to 405
1408 is an output control unit having the same configuration (FIG. 11) as the output control unit 408 shown in FIG. 11, and stores RGB signals stored in the storage unit 1410.
The output RGB signal is controlled by the signal and the 2-bit determination signal H from the determination circuit 409. The log-converted RGB signals are sequentially set in the memory of the storage unit 1410. When the CPU receives the determination signal, it performs data transfer from the memory to the output control unit. The storage unit 1410 functions as a dual port RAM.

Also in this embodiment, if the judgment signal is "0", the RGB signal is output through, if the judgment signal is "1", the G signal and the B signal are inverted, and if the judgment signal is "2", The R signal and the B signal are inverted, and if the judgment signal is “3”, R
The signal, the G signal, and the B signal are all inverted and output. (Third Embodiment) In the first and second embodiments, the output is controlled to invert the image signal to be output in accordance with the determination signal H. However, in the third embodiment described below, the output RG is controlled.
Without changing the B signal, a comparison result, that is, a signal representing a determination result can be output as a control signal. Here, the determination signal H is a 2-bit signal indicating the degree of similarity between the document and the specific image, and is output from the comparator module shown in FIG.

FIG. 13 is a block diagram showing the configuration of the image scanner unit according to the third embodiment. The same circuits as those in FIG. 1 described in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. Reference numerals 2408 and 2409 denote an output control unit and a determination circuit according to the third embodiment, respectively.

In this embodiment, as shown in FIG. 13, the determination signal H output from the determination circuit 2409 is output as it is, and the RGB signal output from the output control unit 408 includes the determination result. It is output as it is without the influence of. (Fourth Embodiment) In the first to third embodiments, a new determination is made each time an image is output. However, in the fourth embodiment described below, a plurality of image If there is no change in the processing and original, RGB according to the first determination result
The output of the signal can be controlled.

FIG. 14 is a block diagram showing the configuration of the image scanner unit according to the fourth embodiment. The same circuits as those in FIG. 1 described in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. 3408 is an output control unit, 3
Reference numeral 409 denotes a determination circuit, 3410 denotes a storage unit, and 3411 denotes a document change detection unit. According to the above configuration, the storage unit 3410 stores the determination result (determination signal H) by the previous scanning received from the determination circuit 3409, and the document change detection unit 3411 detects whether the document has been changed. If there is no change in the document, the output can be controlled according to the previous determination result.

(Fifth Embodiment) In the fifth embodiment, the image signal is not changed in accordance with the judgment result of the judgment circuit as in each of the above-described embodiments. By changing a control signal such as a clock which is indispensable for the transfer of the image data, it is possible to make it impossible for the output destination to receive the RGB signal (image signal). In this embodiment, a video enable signal is changed as a control signal.

FIG. 15 is a circuit diagram showing a configuration of a control signal generation circuit according to the fifth embodiment. In FIG.
01 indicates an AND gate, and 1502 indicates a NOR gate. The fifth embodiment can be realized by providing the control signal generation circuit shown in FIG. 15 in the circuit configuration of FIG. 13 described in the third embodiment, after the determination circuit 2409.

(Sixth Embodiment) In the sixth embodiment, the transmission and reception of the judgment signal H indicating the comparison result between the output RGB signal (image signal) and the specific image signal is performed by transferring the image signal. By incorporating it into the protocol, it is possible to invalidate the output specific image signal.

FIG. 16 is a flowchart illustrating the operation of the image signal output side according to the sixth embodiment, and FIG. 17 is a flowchart illustrating the operation of the image signal input side according to the sixth embodiment. First, on the image signal output side, reading of an image, output (transmission) of the read image signal (RGB signal), and output (transmission) of a comparison result between the output image signal and the specific image signal are performed (step). S1601
S1603).

On the other hand, on the image signal input side, the image signal is input (received) (step S1701), the comparison result is input (received) (step S1702), and the presence or absence of the specific image signal is determined (step S1703). If it is determined that the specified document is present, the input specific image signal is invalidated (step S1704), and the duplication of the specific document can be prevented.

(Seventh Embodiment) In the seventh embodiment, the transfer protocol is stopped when a comparison result indicating that the image signal is a specific image signal is obtained in the sixth embodiment. This makes communication with the output destination impossible. FIG. 18 is a flowchart illustrating a processing procedure of a communication control signal according to the seventh embodiment.

First, when the REQ signal becomes active (step S1801), it is determined whether or not the signal is a specific image signal (step S1802). When the signal is not a specific image signal, the ACK signal is set to active and the processing is performed. When the process is completed (step S1803) and the image signal is a specific image signal, the process returns to step S1801 to repeat the above operation. still,
The present invention may be applied to a system including a plurality of devices or an apparatus including a single device. Needless to say, the present invention can be applied to a case where the present invention is achieved by supplying a program to a system or an apparatus.

In each of the embodiments described above, a laser beam printer is suitable as an output device of the image processing apparatus. However, the present invention is not limited to this, and can be applied to an ink jet printer and a thermal transfer printer. is there. In particular, a so-called bubble jet type printer using a head that discharges liquid droplets using film boiling due to thermal energy may be used.

Further, in each of the above-described embodiments, the original image is input by the image scanner (reader). However, the present invention is not limited to this, and the input is performed by a still video camera or a video camera. It may be created by computer graphics.

[0039]

As described above, according to the present invention, the image
Wait for the image signal output side device to finish determining the similarity with the specific image.
Output a color image signal
The signal input side device determines the determination signal after the input of the color image signal.
Since you can wait for input and decide whether to continue processing,
By disabling the already input color image signal,
It is possible to prevent a specific original from being duplicated .

[Brief description of the drawings]

FIG. 1 is an image scanner unit 201 according to a first embodiment.
FIG. 3 is a block diagram showing a circuit configuration of FIG.

FIG. 2 is a side sectional view showing a schematic internal configuration of the image scanner main body according to the first embodiment of the present invention.

FIG. 3 is a block diagram illustrating a configuration of a determination circuit 409 according to the first embodiment.

FIG. 4 is a circuit diagram showing a configuration of a thinning circuit according to the first embodiment.

FIG. 5 is a circuit diagram showing a configuration of a frequency dividing circuit according to the first embodiment.

FIG. 6 is a block diagram illustrating a configuration of an integrator 306 according to the first embodiment.

FIG. 7 is a timing chart in the main scanning direction in the first embodiment.

FIG. 8 is a diagram showing inputs and outputs of an integrator 306 according to the first embodiment.

FIG. 9 is a diagram showing input and output of an integrator 306 according to the first embodiment.

FIG. 10 shows a comparator module 310 according to the first embodiment.
FIG. 3 is a block diagram showing the configuration of FIG.

FIG. 11 is a block diagram showing a configuration of an output control unit 408 according to the first embodiment.

FIG. 12 is a block diagram illustrating a configuration of an image scanner unit according to a second embodiment.

FIG. 13 is a block diagram illustrating a configuration of an image scanner unit according to a third embodiment.

FIG. 14 is a block diagram illustrating a configuration of an image scanner unit according to a fourth embodiment.

FIG. 15 is a circuit diagram showing a configuration of a control signal generation circuit according to a fifth embodiment.

FIG. 16 is a flowchart illustrating the operation of the image signal output side according to a sixth embodiment.

FIG. 17 is a flowchart illustrating the operation of the image signal input side according to the sixth embodiment.

FIG. 18 is a flowchart illustrating a processing procedure of a communication control signal according to a seventh embodiment.

[Explanation of symbols]

200 Mirror pressure plate 201 Image scanner unit 203 Platen 204 Document 205 Lamp 206, 207, 208 Mirror 209 Lens 210 CCD 210-1, 210-2, 210-3 CCD line sensor 211 Signal processing unit 227 Carriage 301 Thinning circuit 302 LUT 303- 1, 303-2,..., 303-8 Tint determination circuit 306 Integrator 307-1, 307-2, 307-3 Register 308 Comparison module 309 Maximum value circuit 401, 402 Delay element 403-405 Log converter 408 Output Control unit 409 Judgment circuit 455, 456, 457, 461, 462, 463 Flip-flop 458, 459, 460 Selector 464, 465, 466 Flip-flop 451, 453 Inverter 452 2-bit Printer 454 the AND gate 501, 505, flip-flops 502, 503 multiplier 504 adder

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-55-123270 (JP, A) JP-A-60-206263 (JP, A) JP-A-6-60165 (JP, A) JP-A-2- 5682 (JP, A) JP-A-1-303874 (JP, A) JP-A-1-286678 (JP, A) JP-A-55-21611 (JP, A) JP-A-59-72836 (JP, A) (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 1/40 H04N 1/32

Claims (2)

(57) [Claims] An image signal output side device is connected to an image signal input side.
An image that transfers color image signals to the device and duplicates the image
A processing method, wherein the image signal output side device converts a color image signal subjected to color separation into the image signal input side device.
A first output step and the similarity between the specific image and images the color image signal represents the output to
After the start of the output of the color image signal.
And outputting a determination signal indicating the result to the image signal input side device.
A second output step, wherein the image signal input side device receives the color image signal from the image signal output side device.
Inputting the color image signal and outputting the image signal.
A second input step of inputting the determination signal from the force-side device
And, when the determination signal indicates that there is a specific image, the input
Disabling a color image signal.
An image processing method characterized by the following . 2. The image processing method according to claim 1, wherein said image signal output side device is an image scanner or a still camera.