JPH0686053A - Picture processor - Google Patents

Abstract

PURPOSE:To prevent a picture quality from deterioration caused by the addition of a pattern by saving the conspicuousness of the added dot pattern in the whole picture. CONSTITUTION:A pattern adding circuit 109 stores the dot pattern and CPU 111 decides the output level of the dot pattern to arranging-control the dot pattern in main/sub scanning directions. In the case of executing data processing corresponding to a prescribed color among plural different colors based on input picture data, the pattern adding circuit 109 adds the dot pattern of the output level for input picture data corresponding to a prescribed color in accordance with arranging control and outputs it.

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 for adding a pattern to an output image.

[0002]

2. Description of the Related Art In recent years, as the performance of color copiers and color printers has improved, the crime of illegally using them to forge specific manuscripts such as banknotes and securities has increased.
When a crime of this kind occurs, it is almost impossible to identify which device has made a copy, or the person who made a copy, based on the copied copy.

In order to prevent such a crime, data of a pattern corresponding to the specific original document is registered in the color copying machine or the color printer itself, and the image recognition circuit discriminates the data to forcibly make an illegal copy. Prohibitions are being considered. However, such a circuit for preventing forgery has a drawback that all banknotes and securities cannot be registered because the number of image patterns that can be registered is limited.

Further, in a color copying machine or a color printer having an external interface, such a circuit for preventing forgery may not function. For example, if the image data on the external interface is such that the three primary color data of red (R), green (G), and blue (B) are sent at the same time, the circuit for preventing forgery can operate. However, if there are data specifications such as cyan (C), magenta (M), yellow (Y), and black (K) that match the individual characteristics of the printer, there are multiple types of color reproducible combinations. Since a plurality of image patterns for determination are required, determination of forgery prevention becomes extremely difficult, and the number of images that can be determined decreases.

Further, when the image data of each color component is sent frame-sequentially for each color, the image data must be stored in the memory for the image determination, which increases the cost of the apparatus and the forgery prevention determination. There is also a problem that a large amount of cost is required. Further, assuming that the problem of the image signal from the external interface has been solved, even if the number of the specific original document, for example, the number of bills or securities, is limited to the recognizable number, the registration is still performed. It was unavoidable to mistakenly judge a picture that resembles a banknote as a banknote.

Therefore, it is important to add means for preventing forgery to the apparatus itself, but since detection is limited, copying is performed when an original document that should not be copied is copied. It is important to identify the copying machine or the person who copied it. That technology uses the output color component (eg, magenta, cyan, yellow, black) of the copying machine that is the least noticeable to the human eye among the output color components (eg, yellow), and the serial number of the copying machine. The modulation of the image signal of the output color component in the form of numeral or symbol is repeated at regular intervals.

[0007]

However, in the above-mentioned conventional example, even if yellow is the output color component which is the least visible, the modulation of the image signal must be minimized. In particular, when a color copying machine is used for design purposes, it is troublesome to see patterns that are not on the original. When copying an original, even if the original has a uniform color, the image signal will not always be uniform due to variations in the sensitivity of the scanner, etc. Since it is possible to directly output CG (Computer Graphics) when printing out, there may be a sufficient uniform area at the image signal level. At this time, when the yellow component is modulated, there is a problem that the additional pattern becomes conspicuous particularly in a light gray or light blue uniform portion.

Further, in a method of expressing a pattern in a unit in which a number or a code is collected and repeating the pattern in this unit at a constant interval to form an entire additional pattern, each pattern is small and conspicuous. Also, since the human eye is more likely to recognize a regular pattern such as the above-mentioned additional pattern than a randomly arranged pattern, if the pattern is arranged on the lattice, it becomes rather conspicuous. .

Therefore, it is necessary to consider a solution such as a modulation method and a pattern that satisfies the condition that the output image is difficult to identify when viewed with the eyes. Therefore, the present invention, when adding information for identifying a copying machine, a person, etc. as a pattern to an original image, makes the output level of the pattern variable according to image editing and a certain specific time zone,
It is an object of the present invention to provide an image processing device that can add a pattern inconspicuously.

[0010]

[Means for Solving the Problems]
In order to achieve the object, an image processing apparatus according to the present invention is an image processing apparatus that performs data processing corresponding to a plurality of different colors, and a storage unit that stores a dot pattern and a dot pattern stored in the storage unit. Deciding means for deciding the output level, control means for arranging the dot patterns stored in the storage means in the main scanning direction and the sub scanning direction, and a predetermined color among the plurality of different colors based on the input image data. When performing corresponding data processing,
Addition means for adding the dot pattern of the output level determined by the determination means to the input image data corresponding to the predetermined color under the arrangement control of the control means, and output for outputting the result added by the addition means And means.

[0011]

According to this structure, the storage means stores the dot pattern, the determination means determines the output level of the dot pattern stored in the storage means, and the control means sets the dot pattern stored in the storage means in the main scanning direction. The placement control is performed in the sub-scanning direction, and the addition unit performs the data processing corresponding to a predetermined color among a plurality of different colors based on the input image data, the dot pattern of the output level determined by the determination unit is controlled by the control unit. The input image data corresponding to a predetermined color is added according to the arrangement control, and the output means outputs the result added by the adding means.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. In the following embodiments, an example of a copying machine is shown as an application example of the present invention, but the present invention is not limited to this, and it goes without saying that it can be applied to various other apparatuses. First Embodiment [Apparatus Overview] FIG. 2 is a side sectional view showing the internal structure of a copying machine according to the first embodiment of the present invention. In FIG. 2, 2
Reference numeral 01 is an image scanner unit, which is 400 dpi (dot /
This is the part that reads the original at the resolution of inch) and performs digital signal processing. A printer unit 202 is a unit that prints out an image corresponding to the original image read by the image scanner unit 201 on a sheet with a resolution of 400 dpi in full color.

In the image scanner unit 201, 20
Reference numeral 0 denotes a mirror surface pressure plate, and a document 204 on a document table glass (hereinafter referred to as “platen”) 203 is illuminated by a lamp 205, guided to mirrors 206, 207 and 208, and a lens 209 is used to detect a 3-line sensor (hereinafter referred to as “3 line sensor”). , "CC
An image is formed on 210) (referred to as “D”) and is sent to the signal processing unit 211 as full color information red (R), green (G), and blue (B) components. The lamp 205 and the mirror 206 have a speed v, and the mirrors 207 and 208 have a speed 1 /.
By mechanically moving in the direction perpendicular to the electrical scanning (main scanning direction) of the CCD 210 at 2v, the entire surface of the document is scanned (sub scanning).

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, and
One component of Y and Bk is sent to the printer unit 202, and a total of four document scans completes one printout.

The M, C, Y and Bk image signals sent from the image scanner unit 201 are supplied to the laser driver 2.
Sent to 12. The laser driver 212 modulates and drives the semiconductor laser 213 according to the sent image signal. The laser light is the polygon mirror 214 and the f-θ lens 2
15, the photosensitive drum 217 is scanned via the mirror 216.

Reference numeral 218 denotes a rotary developing device, which has a magenta developing section 219, a cyan developing section 220, and a yellow developing section 22.
The first developing unit 222 includes a black developing unit 222 and four developing units alternately contact the photosensitive drum 217 to develop the electrostatic development formed on the photosensitive drum 217 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 to the paper.

In this way, after the four colors M, C, Y and Bk are sequentially transferred, the paper passes through the fixing unit 226, the toner is fixed on the paper, and then the paper is ejected. [Image Scanner] FIG. 1 is a block diagram showing the arrangement of the image scanner unit 201 according to the first embodiment. In the figure, 210-1, 210-2, 210-3 are CCD (solid-state image sensor) line sensors having red (R), green (G), and blue (B) spectral sensitivity characteristics, respectively, and A / After D conversion, signals of 8-bit outputs 0 to 255 are output.

Since the CCD line sensors 210-1, 210-2, 210-3 used in this embodiment are arranged at a fixed distance, the delay element 101 is provided.
And at 102 the spatial offset is corrected. 1
Reference numerals 03, 104 and 105 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 106 is a masking and UCR (undercolor removal) circuit. In the masking / UCR circuit 106, the magenta (M), cyan (C), yellow (Y), and black (Bk) signals for output are output by the input three signals at each reading operation. The data is sequentially output with a predetermined bit length, for example, 8 bits.

A spatial filter circuit 107 corrects the spatial frequency of the output signal. A density conversion circuit 108 corrects the density characteristics of the printer unit 202, and has a ROM or a RAM like the log converters 103 to 105. Reference numeral 111 is a microcomputer (hereinafter, referred to as “CPU”) that controls the present apparatus, and 110 is an input / output port (hereinafter, referred to as “I / O port”) connected to the CPU 111.

The CNO signal is a 2-bit output color selection signal and is a control signal indicating the order of four reading operations. FIG. 12 is a diagram showing the relationship between the CNO signal and the print output according to the first embodiment. The CNO signal is the CPU
It is generated from 111 via the I / O port 110 and switches the operating condition of the masking / UCR circuit 106. 10
Reference numeral 9 denotes a pattern addition circuit, which is a portion for adding a pattern of a color that is difficult for human eyes to identify to the copied image.

FIG. 4 is a diagram for explaining an additional pattern according to the first embodiment. The LUT 303 holds a dot pattern as shown in FIG. 4, that is, an additional pattern. One square in FIG. 4 corresponds to one bit held in the LUT 303, where white indicates 0 and black indicates 1. The horizontal direction corresponds to the lower 4 bits of the address, and the vertical direction corresponds to the upper 4 bits of the address, and the additional pattern is composed of 256 bits. A line in which the upper 4 bits of the address on the left side of FIG. 4 are 0 (the uppermost 1 line) is a mark indicating the reference position. Further, the 6 lines of the upper 4 bits of the address which are shaded on the left side of FIG. 4 and whose upper 4 bits are 2, 3 and 8, 9, E, and F are lines on which dots are placed and are used every two lines. Each of these two lines represents 16 kinds of information by hitting one or two 2 × 2 bit dots at a determined position as shown on the right side of FIG. That is, each 2 lines represent 4-bit information. Since these two lines are three below the mark, it is possible to represent combined 12-bit information. The two lines are not close to each other, but are separated from each other. For example, when two lines of dot arrangement such as “BBB” and “123” are continuous, the dots are connected vertically or diagonally and the additional pattern is conspicuous. This is to prevent it from happening.

The LUT 303 shown in FIG.
It is provided so that it can be written from a CPU (not shown), and in the state where the information for identifying the source of the copy document, such as the information for identifying the transfer machine, is converted into additional pattern data. Written. Also, FIG.
Since the data except the least significant 1 bit of the main scanning counter 302 and the sub-scanning counter 301 is input to the LUT 303, 1 bit on the LUT 303 is 2 on the copy.
It corresponds to 4 pixels of × 2. This is because the printer unit 202 of the present embodiment performs known 200-line processing in the image area, for example, and it may be difficult to read by adding a pattern on a pixel-by-pixel basis.

Next, the pattern adding circuit of this embodiment will be described. FIG. 3 shows an additional circuit 309 according to the first embodiment.
3 is a block diagram showing the configuration of FIG. In the figure, 301
Is a sub-scanning counter, 302 is a main-scanning counter, and 3
Reference numeral 03 is a lookup table RAM (hereinafter referred to as “LUT”), 304 is an AND gate, 1401 to 1404 are registers, 1405 is a 4 + 01 selector, and 309 is A.
The ND gate 310 is an adder.

Here, the sub-scanning counter 301 repeatedly counts the main scanning synchronizing signal HSYNC and the main scanning counter 302 repeatedly counts the pixel synchronizing signal CLK with a 7-bit width, that is, 128 cycles. Further, the LUT 303 is a random access memory (hereinafter referred to as “RAM”) that holds a pattern to be added, and removes the least significant bit from the lower 5 bits of the count value of each of the sub-scanning counter 301 and the main scanning counter 302. 4 bits each are input.

Only one bit is referred to the output of the LUT 303, and this one bit is output by the AND gate 304.
It is logically ANDed with each of the upper 2 bits of the main scanning counter 301 and the sub-scanning counter 302. This result is synchronized with the CLK signal in the flip-flop 305,
The AND gate 307 is ANDed with both of the 2-bit CNO signal “0” and the CNO signal “1” and then sent to the AND gate 309. This is CN
This is a valid signal only when O = 2, that is, when it is currently printed in yellow.

Here, the levels (modulation amounts) of the patterns to be added are registered in advance in the registers 1401, 1402, 1403.
Values 1 P1, P2, P3, and P4 are held in 1404, and any one of P1 to P4 is selected according to the pattern level selection signal PS designated by the CPU 111, and the adder 310 is passed through the AND gate 309. A pattern is added to the input signal V by and V'is output. Therefore, when CNO = 2, that is, when printing is currently performed in yellow, the pattern held in the LUT 303 is repeatedly read and added to the signal V to be output.

The relationship between P1, P2, P3 and P4 is P
It is set so that 1 <P2 <P3 <P4. When S = 00 (binary number), the selector 1405 has Y = A,
S = 01 (binary number), Y = B, S = 10 (binary number), Y = C, S = 11 (binary number), Y =
Since it is set to be D, when PS = 00 (binary number), V ′ = V + P1, when PS = 01 (binary number), V ′ = V + P2, PS = 10 (binary number) When
When V '= V + P3 and PS = 11 (binary number), V' =
The pattern is added such that V + P4.

By varying the level of the pattern to be added according to the editing function of the input image, the pattern is recorded on the copy such as enlarging / reducing / separating so that it can hardly be recognized by human eyes. . As described above, according to the first embodiment, when the document is edited, the modulation amount of the image signal can be reduced, so that it can be made even more inconspicuous.

<Second Embodiment> Now, the second embodiment will be described below.
In this embodiment, when the additional pattern is superimposed on the original image to generate a reproduced image, a dot array in which the additional pattern is dispersed is used. In the second embodiment as well, since the overall construction of the copying machine is the same as in FIGS. 1 and 2 described in the first embodiment,
The description is omitted.

[Pattern Addition Circuit] First, the method of the addition pattern of this embodiment will be described. 7 is a diagram showing an additional pattern according to the second embodiment, FIG. 8 is a diagram for explaining add-on lines according to the second embodiment, and FIG. 9 is a diagram for explaining units of an additional pattern according to the second embodiment. 10 is the second
11A and 11B are views for explaining an example of adding an additional pattern according to the embodiment of the present invention, and FIG. 11 is a view for explaining a method of adding a mark according to the second embodiment.

As shown in FIG. 7, the additional pattern of this embodiment has dots as a unit by modulating (for example, + α) the image signals of 16 pixels of 4 × 4 pixels in total. This is because the printer unit of the color copying machine performs, for example, 200 line processing in the image area, and it may be difficult to read by adding a pattern on a pixel-by-pixel basis. As shown in FIG. 8, the dots arranged in the main scanning direction at regular intervals of 8 mm (128 pixels) are called add-on lines. The add-on lines are arranged at equal intervals in the sub-scanning direction at intervals of 1 mm (16 pixels). As will be described later, one add-on line represents 4-bit information, and eight add-on lines represent all additional information (3
2 bit), which is repeated in the sub-scanning direction (FIG. 9). As shown in FIG. 10, information is added to each add-on line by the phase difference of the dot position when compared with the immediately preceding add-on line. However, in order to prevent the dots from approaching and becoming conspicuous, do not hit near the dot of the previous add-on line. In addition, one of eight add-on lines (Line0 to Line7) representing all additional information
Dots are added to the right of each dot in the second add-on line (Line 0) and the fourth add-on line (Line 3). As shown in FIG. 11, in Line 0, a dot is added 1 mm to the right of the original dot position, and in Line 3, a dot is added 2 mm to the right. This is a mark for clarifying which part of all the additional information each add-online represents. If the add-on line to add the mark is one, the upper and lower sides in the sub-scanning direction cannot be determined from the copy, so the dot of the mark is added to the two add-on lines. Here, the pattern to be added is added only with the yellow toner so that it is difficult for the human eye to identify, but this is because the human eye has a weak identification ability with respect to the pattern drawn with the yellow toner. Is used.

Next, the pattern adding circuit of this embodiment will be described. 5 and 6 are block diagrams showing the configuration of the pattern adding circuit according to the second embodiment. In the figure, 1319 is a sub-scanning counter, and 1314 is a main-scanning counter. Here, the sub-scanning counter 1319 outputs the main scanning synchronization signal HSYNC, and the main scanning counter 1314 outputs the pixel synchronization signal CLK with a 7-bit width, that is, 128 bits.
Counts repeatedly in a cycle. The output of the AND gate 1320 becomes H when both the bits 2 and 3 of the sub-scanning counter 1319 are H. That is, H is 4 lines for every 16 lines in the sub-scanning direction. This is the enable signal for the add-on line. Further, the output from the AND gate 1320 and the upper 3 bits of the sub-scanning counter 1319 are input to the gates 1322 and 1321 so that LINE
0, LINE3 is generated. This is a signal which becomes H at the time of Line 0 and Line 3 in the add-on line. On the other hand, the main scan counter 1314 is loaded with an initial value by HSYNC. Since the upper 5 bits of the main scanning counter 1314 are input to the AND gate 1315, the output becomes H for 4 pixels for every 128 pixels. This is the dot enable signal. Also, the gate 13
Reference numerals 16 and 1317 denote the upper 5 bits of the main scanning counter 1314 and the outputs LINE0 and L of the gates 1322 and 1321.
INE3 and the input, each of the online Li
An enable signal for dots of the marks ne0 and Line3 is generated. These dot and mark enable signals are combined by the OR gate 1318. This OR
The output of the gate 1318 is high even if it is not online
Therefore, the AND gate 1324 is set to L except the add-on line. This AND gate 13
The output of 24 is synchronized with the CLK signal in the flip-flop 1325, and 2 in the AND gate 1327.
After being ANDed with both CNO signals "0" and "1" of the bit, it is sent to AND gate 1329. This is a valid signal only when CNO = 2, ie currently printed in yellow.

Reference numeral 1705 denotes a 4to1 selector, 17
01, 1702, 1703, 1704 are registers, and registers 1701, 1702, 1703, 1704
The values P1, P2, P3 and P4 are held in advance in the pattern level selection signal PS specified by the CPU.
Any of P1 to P4 is selected according to
A pattern is added to the input signal V by the adder 1330 via the D gate 1329, and V ′ is output.

Here, the operation of the selector 1705 according to the relationship among P1, P2, P3 and P4 is the same as that of the first embodiment, and therefore its explanation is omitted. Also in the second embodiment, when the image is edited, the modulation amount of the image signal can be reduced, so that it can be made more inconspicuous. <Third Embodiment> In the first and second embodiments, a timer capable of setting a plurality of time zones is provided, and the output level of the pattern to be added is made variable according to the time zones. . For example, increase the output level at midnight,
By lowering the output level at noon, the pattern can be recorded on a normal copy so that it is almost invisible to the human eye.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of a single device. Further, it goes without saying that the present invention can be applied to the case where it is achieved by supplying a program to a system or an apparatus.

[0036]

As described above, according to the present invention, the conspicuousness of the dot pattern added in the entire image can be suppressed, and the image quality deterioration due to the addition of the pattern can be prevented.

[Brief description of drawings]

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

FIG. 2 is a sectional view showing the internal structure of the copying machine according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing the configuration of a pattern adding circuit 109 according to the first embodiment.

FIG. 4 is a diagram illustrating an additional pattern according to the first embodiment.

FIG. 5 is a block diagram showing a configuration of a pattern adding circuit according to a second embodiment.

FIG. 6 is a block diagram showing a configuration of a pattern adding circuit according to a second embodiment.

FIG. 7 is a diagram showing an additional pattern according to a second embodiment.

FIG. 8 is a diagram illustrating an add-on line according to a second embodiment.

FIG. 9 is a diagram illustrating a unit of an additional pattern according to a second embodiment.

FIG. 10 is a diagram illustrating an example of adding an additional pattern according to the second embodiment.

FIG. 11 is a diagram illustrating a method of adding marks according to the second embodiment.

FIG. 12 is a diagram showing a relationship between a CNO signal and print output according to the first embodiment.

[Explanation of symbols]

 101, 102 Delay element 103-105 Log converter 106 Masking UCR circuit 107 Spatial filter 108 Density converter 110 I / O 111 CPU 201 Image scanner 202 Printer unit 203 Original platen glass 204 Original 205 Lamp 206-208 Mirror 210-1 210-3 CCD sensor sensor 212 laser driver 213 semiconductor laser 214 polygon mirror 215 f-θ lens 216 mirror 217 photosensitive drum 218 rotary developing device 219 magenta developing unit 220 cyan developing unit 221 yellow developing unit 222 black developing unit 223 transfer drum 224. 225 paper cassette 226 fixing unit 301 sub-scanning direction counter 302 main-scanning direction counter 303 LUT 304/307/308 AND gate 305 flip-flop 306 inverter 1401 to 1404 register

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location H04N 1/40 Z 9068-5C

Claims (3)

[Claims] 1. An image processing apparatus for performing data processing corresponding respectively to a plurality of different colors, storage means for storing a dot pattern, determination means for determining an output level of the dot pattern stored in the storage means, The control means for arranging the dot patterns stored in the storage means in the main scanning direction and the sub-scanning direction and the data processing corresponding to a predetermined color of the plurality of different colors based on the input image data Adding means for adding the dot pattern of the output level determined by the means to the input image data corresponding to the predetermined color according to the arrangement control of the controlling means, and output means for outputting the result added by the adding means An image processing apparatus comprising: 2. An image processing apparatus for performing data processing respectively corresponding to a plurality of different colors, wherein a storage means for storing a dot pattern and an output level of the dot pattern stored in the storage means are determined according to a time zone. Determining means, control means for arranging the dot patterns stored in the storage means in the main scanning direction and the sub scanning direction, and data processing corresponding to a predetermined color among the plurality of different colors based on input image data. In the case of performing, an addition unit that adds the dot pattern of the output level determined by the determination unit to the input image data corresponding to the predetermined color according to the arrangement control of the control unit, and a result added by the addition unit. An image processing apparatus comprising: an output unit for outputting. 3. The image processing apparatus according to claim 2, further comprising setting means for setting the relationship between the time zone and the output level.