JPH09135361A - Device and method for processing image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain specified information based on a color image formed by the image processing device by adding a specified pattern denoting specified information provided by the processing device supplier to a color image in the case of outputting the color image visually onto a recording medium through the use of plural color materials. SOLUTION: A code 1001 is an added pattern and the content stored in a ROM is added to an output image. In this example, a pattern of ABCD1234 is added as a pattern of 64 picture elements × 64 picture elements in a way identified hardly by human eyes, and the addition is repeated for each of main scanning 512 picture elements and subscanning 512 lines. The added pattern indicates a manufacture number specific to a machine or a coded manufacture number, then in the case of providing an expert opinion to a copy, the copying machine is limited. Furthermore, when there is the possibility of a specified original that should not be copied substantially in a read image, a clear pattern is added to the main image. That is, the density of the pattern is changed in accordance with the possibility of being the specified original.

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 method for recording specific information by adding a specific pattern in an image processing apparatus for forming an image on a recording medium based on input image data. Is.

[0002]

2. Description of the Related Art In recent years, image processing apparatuses capable of forming color images, such as color copying machines and color printers, have become capable of forming high quality color images. For this reason, there is an increasing possibility that a specific image (for example, securities, bills) that should not be copied by using this image processing apparatus is illegally created.

[0003]

However, conventionally,
When a specific original that should not be originally copied is copied, a method for obtaining specific information such as the image processing apparatus or the user who copied the copy has not been specifically considered.

For example, as a method of obtaining specific information, it is conceivable to add a header or the like indicating specific information to an image formed by each image processing apparatus as in the case of FAX, but the original image is visually changed. Therefore, it becomes impossible to visually output a high quality image.

Further, if the user can rewrite it like a normal FAX header, the device identification information or the user information may be intentionally set to be wrong.

The present invention has been made in order to solve the problems of the prior art, and it is possible to obtain specific information based on a color image formed in an image processing apparatus for visually outputting a color image. In addition, it is an object of the present invention to prevent the formed color image from visually changing from the original color image.

A further object is to make the above-mentioned specific information reliable.

Further, the above object is achieved by a simple image forming method.

[0009]

In order to solve the above problems, according to the image processing apparatus of the present invention, input means for inputting color image data, and a color image indicated by the color image data input by the input means. And output means for visually outputting on a recording medium using a plurality of color materials, wherein the output means is not all of the color materials of a plurality of colors, but a color material of a color that is difficult to identify with human eyes. On the other hand, a specific pattern indicating specific information given by the device provider is added.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) [Apparatus Overview] FIG. 2 shows an overview of an apparatus according to a first embodiment of the present invention. In FIG. 2, 201 is an image scanner unit, 400 dpi (dots / inch)
This is a part that reads a document at the resolution of and performs digital signal processing. Reference numeral 202 denotes a printer unit which prints out an image corresponding to the document image read by the image scanner 201 in full color on a sheet at a resolution of 400 dpi.

In the image scanner 201, 20
Reference numeral 0 denotes a mirror pressure plate, and a platen glass (hereinafter, platen) 2
The original 204 on the original 03 is irradiated by a lamp 205, guided to mirrors 206, 207 and 208, and forms an image on a three-line CCD sensor (hereinafter referred to as a CCD) 210 by a lens 209. (G) and blue (B) components are sent to the signal processing unit 211. Note that 205 and 206 are speeds v, 207, 2
Reference numeral 08 scans the entire original surface (sub-scanning) by mechanically moving the line sensor in the direction perpendicular to the electrical scanning (main scanning) direction at a speed of 1/2 v.

In the signal processing unit 211, the read image signal is electrically processed and decomposed into magenta (M), cyan (C), yellow (Y), and black (Bk) components, and the printer unit. Send to 202. In addition, M, C,
One component of Y and Bk is sent to the printer unit 202, and a single print of the reproduced image is completed by a total of four document scans.

The M, C, Y and Bk image signals sent from the image scanner unit 201 are sent to the laser driver 212. The laser driver 212 modulates and drives the semiconductor laser 213 according to the sent image signal. The laser light is applied to the polygon mirror 214, f
The photosensitive drum 2 via the −θ lens 215 and the mirror 216
Scan over 17.

Reference numeral 218 denotes a rotary developing device, which includes a magenta developing portion 219, a cyan developing portion 220, a yellow developing portion 221,
The developing unit includes a black developing unit 222. The four developing units alternately contact the photosensitive drum 217, and develop the electrostatic development formed on the photosensitive drum with toner.

Reference numeral 223 denotes a transfer drum which winds the paper supplied from the paper cassette 224 or 225 around the transfer drum 223 and transfers the image developed on the photosensitive drum onto the paper.

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

[Image Scanner] FIG. 1 is a block diagram of the image scanner unit 201.

210-1, 210-2 and 210-3 are red (R), green (G) and blue (B), respectively.
(CCD) sensor having a spectral sensitivity characteristic of A. The image signal read by this sensor is A
After being subjected to / D conversion, they are output as 8-bit output signals 0 to 255, respectively.

The sensor 210 used in this embodiment
-1, 210-2 and 210-3 are arranged in parallel with a certain distance therebetween, so that the delay elements 401 and 4
In 02, the spatial shift is corrected.

Reference numerals 403, 404, and 405 denote log converters, which are constituted by a look-up table ROM or RAM and convert a luminance signal into a density signal. Reference numeral 406 denotes a known masking and UCR (under color removal) circuit.
Based on the three input signals, magenta (M), cyan (C), yellow (Y), and black (Bk) signals are sequentially and sequentially output with a predetermined bit length, for example, 8 bits.
Because of the surface-sequential projection, the CCD sensors 210-1 to 210-1
0-3 performs four scans.

A known spatial filter circuit 407 corrects the spatial frequency of the output signal. Reference numeral 408 denotes density conversion means for correcting the density characteristics of the printer unit 202, and is constituted by a ROM or RAM similar to the log converters 403 to 405.

On the other hand, 414 is a microcomputer (hereinafter CPU) which controls the apparatus, and 413 is a CP.
An input / output port (hereinafter referred to as an I / O port) connected to the U 414, and a reference numeral 409 is a means for determining a specific document.

Here, the specific manuscript judging means 409 judges whether the manuscript placed on the manuscript table is at least one of a plurality of predetermined manuscripts, and judges signal H indicating the possibility. Is output with multi-valued 2 bits. That is,
If at least one of the plurality of specific originals is most likely to be output, H = “3” is output, and if it is least likely, H = “0” is output.

The CNO signal is a 2-bit frame sequential signal, and is a control signal indicating the order of four read operations as shown in Table 1. The CPU 414 causes the I / O port 413 to operate.
And switches the operating conditions of the masking / UCR circuit 406.

[0025]

[Table 1]

Further, the above-described frame sequential signal CNO is also input to the determination means 409, and the determination reference can be switched for each of the four reading operations to determine different specific originals.

Reference numeral 410 is a pattern addition circuit, which is a CP.
In accordance with the 2-bit pattern level selection signal PS specified by U414, a pattern that is difficult for human eyes to identify is added to the copied image.

[Timing Chart] FIG. 6 shows a main scanning timing chart in the present embodiment. VS
The YNC signal is a sub-scanning section signal, which is a signal indicating the 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 a transfer clock of an image, which is a basic clock for various image processes in the present embodiment.

On the other hand, CLK4 is obtained by dividing the CLK signal by 1/4 and serves as a basic clock in the judging means 409. The SEL signal is a timing signal used in the above-described thinning circuit 301, and is a signal shown in FIG.
Is generated by a circuit as shown in FIG. That is, the inverter 4
51, a 2-bit counter 452, an inverter 453, and an AND gate 454. 2-bit counter 4
52 is an HSYNC signal which is a main scanning synchronization signal,
After being cleared (initialized), the CLK signal is counted,
The count value is output with 2 bits. (D0, D1)
The upper bit D1 is output as the CLK4 signal, and the logical product of the inverted signal of the lower bit D0 and the upper bit D1 is output as the SEL signal.

As a result, in the circuit shown in FIG. 4A, the flip-flop 4 which holds data by the CLK signal.
55, 456, 457 and 461, 462, 463;
Selectors 458, 459, 460, flip-flops 464, 465, 466 holding data by CLK4 signal
As shown in FIG. 6, the R (or G, B) signal transferred by the CLK signal is thinned out at a rate of 1/4 and synchronized with CLK4 by the thinning circuit constructed as described above. R ′ (or G ′, B ′) signal can be obtained.

[Determination Means] FIG. 3 shows a block diagram of the determination means 409.

Reference numeral 301 denotes a thinning circuit as shown in FIG. 4, which thins data in order to reduce the load on the processing circuit of the judging means. Reference numeral 302 denotes a color matching look-up table ROM (read-only memory), which performs color matching with a plurality of types of specific originals.

The tint distributions of 32 types of specific originals are checked in advance, and the result of determination as to whether the tint of the pixel matches the tint of the specific originals is held.

That is, the CNO signal, which is a frame sequential signal, is input to the upper 2 bits of the address and the upper 5 bits of the image signal of each color of RGB, which are thinned out to the lower 15 bits, are input to the ROM 302. The value of each plane sequential signal CNO 0
3 to 3 simultaneously output whether or not the color of the pixel matches the color of the eight types of specific originals in correspondence with the 8-bit data. Is determined.

303-1, 303-2, ..., 303
Reference numeral -8 denotes a color determination circuit constituted by the same hardware, and includes an integrator 306, registers 307 and 308,
309, a comparator module 310, each of which determines the possibility that a specific document exists in the document by two bits. Reference numeral 309 denotes a maximum value circuit.
The maximum value of the judgment result outputs of 03-1 to 303-8 is output. That is, a determination result is output for the largest one of the eight types of specific originals.

[Integrator] FIG. 5 shows a block diagram of the integrator 306.

Reference numerals 501 and 505 denote flip-flops that hold data at the rising timing of the CLK4 signal.

Reference numeral 502 denotes a multiplier, which inputs 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 × B) as a multiplication result.

An adder 504 inputs an 8-bit 2-input signal (A, B) and outputs an 8-bit signal (A + B) as an addition result.

As a result, in this integrator, the 8-bit output signal y _i is represented by the following equation for the binary input signal x _i .

Y _i = (α / 255) y _i-1 + β x _i-1 where α and β are preset constants, and the characteristics of the integrator are determined by the magnitude of these values. .

For example, when α = 247 and β = 8, an example of input / output of this integrator is shown in FIG. That is, (a)
For the input x _i−1 as shown in ( ₁ ), the output y _i as shown in (b) is output.

Here, inputs such as 701 and 702 are "1" even though the surroundings are almost "0",
An input such as 703 whose surroundings are almost “1” but are still “0” is considered to be noise. This is processed by the integrator and the register 307 of FIG.
704 (R1), 704 ′ (R2), 704 ″ (R
By setting an appropriate threshold value as in 3) and binarizing the output y _i of the integrator with this, noise (noise) can be removed.

[Comparator Module] FIG. 8 shows a block diagram of the comparator module 310. 801, 802, 80
3 is a comparator, 804 is an inverter, and 805 is AN
D gates and 806 and 807 are OR gates. In advance,
R1 is set in the register 307, R2 is set in the register 308, and R3 is set in the register 803.
>R2> R3. With this configuration, as a result, the determination result is quantized into two bits and output. That is, when R1 <(input), 11 is output, when R2 <(input) ≦ R1, 10 is output, and when R3 <(input) ≦ R2, 01 is output,
If (input) ≦ R3, 00 is output.

This output signal indicates that the input image may be a specific original.

[Pattern Adding Circuit] FIG. 9 shows a block diagram of the pattern adding circuit 410. Reference numeral 901 denotes a sub-scanning counter; 902, a main scanning counter; 903, a lookup table ROM; 905, a flip-flop;
3 is an AND gate, 906, 907, 908, and 909 are registers, 910 is a 4to1 selector, and 911 is AN
D gate, 912 is an adder, 913 is an AND gate, and 914 is an inverter.

Here, the sub-scanning counter 901 repeatedly counts the main scanning synchronizing signal HSYNC, and the main scanning counter 902 repeatedly counts the pixel synchronizing signal CLK with a 9-bit width, that is, 512 cycles. Reference numeral 903 denotes a read-only memory (hereinafter referred to as RO) in which a pattern to be added is held.
M), the sub-scanning counter 901 and the main scanning counter 9
02 The lower 6 bits of each count value are input. The output of the ROM 903 refers to only one bit, and is output by the AND gate 904 to the main scanning counter 901.
And the upper 3 bits of the sub-scanning counter 902 are ANDed, the flip-flop 905 synchronizes with the CLK signal, and the AND gate 913 sets the upper bit of the 2-bit field sequential signal to CNO1 and the lower bit Is logically ANDed with both the inverted signal of CNO0 and CNO1, and then sent to the AND gate 911. This is a signal effective only when CNO = 2, that is, when printing is currently performed in yellow.

On the other hand, the registers 906, 907, 908,
909 holds in advance the values P1, P2, P3, and P4, and any one of P1 to P4 is selected according to the pattern level selection signal PS specified by the CPU, and the AND gate 911 is set. Thereafter, the adder 912 adds a pattern to the input signal V and outputs V ′. Therefore, when CNO = 2, that is, when the image is currently printed in yellow, the pattern held in the ROM 903 is repeatedly read and added to the signal to be output.

Here, it is set that P1 <P2 <P3 <P4, and the selector 910 is s = 00 (binary number) Y = A s = 01 (binary number) Y = B s = 10 (binary number) Y = C s = 11 (binary number) Y = D is set, so that PS = 00 (binary number) V '= V + P1 PS = 01 ( In the case of binary number) V '= V + P2 When PS = 10 (binary number) V' = V + P3 When PS = 11 (binary number) V '= V + P4

Here, the added pattern is added only by the yellow toner so that it is difficult for the human eye to identify it. This is because the human eye does not recognize the pattern drawn by the yellow toner. It utilizes the weak identification ability. Furthermore, by changing the level of the pattern to be added according to the possibility that the specific document exists in the input image, the pattern can hardly be recognized by human eyes in a normal copy, and the specific document can be identified. The higher the possibility of the existence, the sharper the pattern is added.

[Copy Result] FIG. 10 shows an example of the copy result in the present embodiment. The pattern 1001 is the added pattern, and the contents held in the ROM 903 are added. In the example shown in FIG. 10, “ABCD12
The 34 ″ pattern is added in a pattern of 64 pixels × 64 pixels and is repeated every 512 pixels of main scanning and 512 lines of sub-scanning so that it cannot be easily recognized by human eyes.
Therefore, by setting this as a serial number unique to the machine or by encoding the serial number, the copied device can be identified, and the copied device can be limited.

Further, when there is a high possibility that a specific original document that should not be copied exists in the read image,
You can also add a clear pattern. That is, the density of the pattern can be changed according to the possibility of being a specific original.

Further, in the present embodiment, the pitch for adding the pattern is set to 512 pixels (or lines) in the main scan.
However, in the present embodiment, 400 dpi (d
ots / inch) resolution, so about 32.5m
A pattern will be added for each m. On the other hand, the width of banknotes (Bank of Japan notes) in the lateral direction is about 76 mm, and the width of banknotes in major countries is also about 60 mm.
Since this is between 120 mm and 120 mm, when a bill is copied, this pattern is always added to the inside of the copied bill. Therefore, even if only the bill portion is cut off and misused, the copy number can be identified by examining the copy and reading the added pattern.

[Flowchart] FIG. 11 shows the CPU 41.
4 controls the pattern level selection signal PS.
2 is a flowchart for the set of.

First, immediately after the start of copying, step 1
At 102, the pattern level selection signal PS is set to "0".
Is set. Next, in step 1103, the current determination level H is compared with the value of PS. If H is larger, the value of H is set in PS in step 1104. Otherwise return to 1103. That is, according to the history of the determination signal H, the maximum value from the copy start to the present is P
Set to S.

(Second Embodiment) The present invention is not limited to the above-described first embodiment. For example, in the first embodiment, as the specific pattern to be added,
Although the device-specific serial number or an encoded product number is added, the information is not limited to this as long as it is information for identifying the device.

For example, it may be other information for identifying the device, such as the manufacturing date of the device, the lot number of the device, the version of the device, or the like.

(Third Embodiment) In the first and second embodiments, the copying apparatus is specified, but the present invention is not limited to this, and the copying person is limited. It may be one.

For example, a device which requires insertion of an ID card for limiting the user or a device which requires input of an ID number has been already known when using the device. In the device, the recognized ID number or the encoded ID number may be added as a specific pattern.

Also, the copied date or the encoded date may be added as a specific pattern.

As described above, according to the above-described embodiment of the present invention, as a method for identifying a device, a specific pattern that is difficult for human eyes to identify is added to a copy. When a specific original document that should not be copied (for example, a banknote) is copied, it can be used as a clue to limit the copying device. Furthermore, by repeatedly adding a specific pattern at a pitch shorter than the length of the banknote in the short direction, even if a part of the copy is cut off and misused, the specific pattern is always added to the copy. Then, by limiting this, the copied device or the copied person is determined. Or you can narrow it down.

In the above embodiment, the laser beam printer has been described as an example, but the invention can be applied to an ink jet printer and a thermal transfer printer.

In particular, a so-called bubble jet type printer using a head of a type for ejecting droplets by utilizing film boiling due to thermal energy may be used.

Further, the color to be added is not limited to yellow, but may be an inconspicuous color such as yellowish green or gray, or a color with high lightness such as light purple or light green.

Further, the document is not limited to the original input by the reader, but may be one input by a still video camera or a video camera, or one created by computer graphics.

[0066]

As described above, according to the present invention, when a color image is visibly output on a recording medium using color materials of a plurality of colors, a specific information given by the apparatus provider is specified. Since the pattern is added, the specific information can be obtained based on the color image formed by the image processing apparatus.

Particularly, not all of the color materials of a plurality of colors forming a color image, but the color material of a color which is difficult for the human eye to identify (a color such as yellow which is inconspicuous to the human eye in this embodiment). Since the specific pattern is added, it is possible to suppress visual deterioration of the image quality of the formed color image as a whole.

Further, since the device provider provides the specific information, the reliability of the specific information is increased, and the location of each device, the user, etc. can be easily managed by the device provider.

Further, since a recording method of magnetic information or the like is not used together to add specific information, and an image is formed by a single image forming method (a laser beam printer in this embodiment), the image forming unit Easy device configuration

[Brief description of the drawings]

FIG. 1 is a block diagram of an image scanner unit.

FIG. 2 is an external view of the apparatus according to the first embodiment.

FIG. 3 is a block diagram of a determination unit.

FIG. 4 is a block diagram of a thinning circuit and a frequency dividing circuit;

FIG. 5 is a block diagram of an integrator.

FIG. 6 is a timing chart.

FIG. 7 is a diagram showing timings of input / output signals in an integrator 306;

FIG. 8 is a block diagram of a comparator module 310.

FIG. 9 is a block diagram of a pattern adding circuit 410.

FIG. 10 is a diagram illustrating an example of a copy result according to the embodiment;

FIG. 11 is a flowchart showing a control flow.

[Explanation of symbols]

 202 image scanner unit 203 printer unit 306 integrator 308 comparison module 409 specific document determination unit 410 pattern addition circuit 414 CPU

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location H04N 1/46 H04N 1/46 Z

Claims (3)

[Claims] 1. An input device for inputting color image data, and an output device for visually outputting a color image represented by the color image data input by the input device onto a recording medium by using color materials of a plurality of colors. However, the output means may add a specific pattern indicating specific information given by the apparatus provider to a color material of a color that is difficult to be identified by human eyes, not all of the color materials of the plurality of colors. A characteristic image processing device. 2. The image processing apparatus according to claim 1, wherein the specific information provided by the apparatus provider is information for identifying the image processing apparatus. 3. When color image data is input and a color image indicated by the input color image data is visually output on a recording medium using a plurality of color materials, all of the plurality of color materials are used. An image processing method characterized by adding a specific pattern indicating specific information provided by an apparatus provider to a color material having a color that is difficult to identify with human eyes.