JPH06334841A - Image forming device with tracking function - Google Patents

Abstract

(57) [Summary] [Purpose] When copying prohibited items such as banknotes and securities,
A code pattern that is easy to read is printed on the copy surface to speed up and ensure the tracking operation. In an image forming apparatus with a tracking function, which performs predetermined image processing on image data read from a document and outputs an image, a specific pattern having a reference pattern serving as a reference position of the pattern is stored inside the pattern. Memory 305 and a synthesizing unit 306 for synthesizing a specific pattern from the memory 305 and synthesizing the image data with each other, and clarifying the reference position indicated by the reference pattern portion facilitates decoding of the specific pattern. .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention adds a legible specific identification pattern to a copy-prohibited object such as paper money or securities, and outputs the copy from the pattern. The present invention relates to an image forming apparatus with a tracking function such as a digital color copying machine that can identify the apparatus.

[0002]

2. Description of the Related Art Conventionally, with the spread of full-color copying machines and the improvement in image quality of output images, the social problem of counterfeiting copy prohibited items such as banknotes and securities has been further highlighted. For such a problem of abuse copying,
For example, there is an "image forming apparatus" disclosed in Japanese Patent Laid-Open No. 4-294682. This is for forming an image by adding a specific pattern of a color that is hardly recognized by the human eye to an image signal. For example, a device-specific identification number or code is added as a specific pattern to identify the device. However, the person who finally made the counterfeit copy can be traced.

[0003]

However, in the conventional image forming apparatus as described above, it is necessary that the specific pattern to be added cannot be easily identified by human eyes due to its nature. Further, there is a problem that if the specific pattern is a pattern such as alphanumeric characters that can be easily identified by humans, it may have an unfavorable effect on the image data. On the other hand, it is possible to use a code for the pattern to be added and print the code to make it difficult to identify.
Since the printed code is difficult to see, there is a problem that it becomes difficult to decipher the pattern, the tracking work takes time, and the tracking work becomes difficult.

The present invention has been made in view of the above, and when a copy-prohibited object such as banknotes or securities is copied, a code pattern that is easy to read is printed on the copy surface.
The purpose is to speed up and ensure the tracking work.

[0005]

In order to achieve the above object, the present invention provides an image forming apparatus with a tracking function, which executes predetermined image processing on image data read from a document and outputs an image. Tracing comprising pattern data storage means for storing a specific pattern having a reference pattern as a reference position of the pattern inside the pattern, and synthesizing means for reading the specific pattern from the pattern data storage means and synthesizing with the image data An image forming apparatus with a function is provided.

Further, the specific pattern stored in the pattern data storage means is a directional pattern.

[0007]

In the image forming apparatus with the tracking function according to the present invention, the specific pattern to be added to the image signal is defined as a specific pattern in which a reference pattern serving as a reference position of the pattern is provided, and the reference position indicated by the reference pattern portion is shown. Makes it easier to decipher a specific pattern.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram showing the main configuration of an image forming apparatus with a tracking function according to the present invention. In the figure,
Reference numeral 101 denotes an image reading unit that reads document information by scanning or sequentially from storage means such as a memory as image data, and 102 executes a predetermined processing process (described later) on the image data read by the image reading unit 101. An image processing unit 103 is an image recording unit that outputs the image data processed by the image processing unit 102 to recording paper or the like.

Next, the operation will be described. The image data read by the image reading unit 101 is the image processing unit 10.
2 is input, various image processing is executed, and then output to the image recording unit 103. The image recording unit 103 outputs the image data on recording paper.

FIG. 2 is a block diagram showing a schematic configuration of the image processing unit 102. In the figure, 201 is RGB
A scaling processing unit for independently performing main scanning scaling processing for each data signal of the image data signal, 202 is an MTF correction for the RGB image data signal in order to correct blurring of a lens optical system (not shown) RGB filter for executing (sharpening) processing, 203 is an RGB γ correction unit for executing γ correction processing such as gray balance of RGB image data signals, and 204 is RG.
A processing unit 205 executes various processing such as mirror processing, italic processing, shadowing processing, paint processing, moving processing, etc. on the B image data signal as necessary, and 205 is based on a primary masking equation. The color correction unit performs color conversion processing for converting the data system from the RGB image data signal to the YMCK image data signal.

Reference numeral 206 denotes a YMCK γ correction unit for executing γ correction processing according to the γ characteristic of the image recording unit 103, and 20.
Reference numeral 7 denotes a YMCK filter that executes filtering processing such as smoothing and sharpening according to the MTF characteristics of the image recording unit 103, and 208 executes halftone processing to convert YMCK signals to Y ′, M ′, C ′, K '(However, the number of bits is C>C',
M> M ', Y>Y',K> K ') a dither processing unit for converting into a color signal, and 209 a tracking pattern unit (described later) for adding a specific pattern to the image signal output from the dither processing unit 208. Yes).

Next, the operation of the image processing unit 102 will be described. The RGB image data is subjected to main scanning scaling processing independently for each image data signal in the scaling processing unit 201, MTF correction (sharpening) processing is executed in the RGB filter 202, and RGBγ correction unit 203 is executed. , Γ correction processing such as gray balance is executed, various processing processing such as mirror processing and italic processing is executed in the processing processing unit 204, and the RGB image data signal is converted into the YMCK image data signal in the color correction unit 205. Convert the data system.

After that, the YMCK image data is YMCK.
In the γ correction unit 206, γ correction processing is executed according to the γ characteristic of the image recording unit 103, and the YMCK filter 207
In, a filtering process such as smoothing or sharpening is executed in accordance with the MTF characteristic, and a dither processing unit 208 executes a halftone process to convert each signal of YMCK into Y ′,
Dither processing for converting into M ′, C ′, and K ′ color signals is executed, and a specific pattern is added in the tracking pattern unit 209.

FIG. 3 is a block diagram showing a schematic structure of the tracking pattern unit 209. In the figure, 301 is the pixel clocks 0 to 255 in synchronization with the synchronization signal in the main scanning direction.
Is a main scanning counter that repeatedly counts and outputs the signals A _{0 to} A ₇ . The LSB in this case is A ₀ . A sub-scanning direction counter 302 repeatedly counts the line synchronization signals 0 to 255 in synchronization with the sub-scanning direction synchronization signal and outputs signals A _{0 to} A ₇ . The LSB in this case is A ₀ .

Reference numeral 303 is a selector connected to the output side of the main scanning counter 301, and 304 is a selector connected to the output side of the sub-scanning direction counter 302. Also,
Inputs A of the selectors 303 and 304 are inputted with respective outputs of the main scanning counter 301 and the sub-scanning direction counter 302, and an input B is inputted with an address signal from a CPU (not shown). There is. Also, output Y
Is configured to select whether to output the input A or the input B from the CPU.

305 has a capacity of 2 Kbytes, addresses A _{0 to} A ₁₃ , and selectors 303 and 30.
4 is a memory in which each output of 4 is connected to the input side. Further, WE of the memory 305 inputs a memory line signal from the CPU, D ₁ is a data input, and inputs data from the CPU. D ₀ is a data output and CP
It is configured to output data from U. When WE is HIGH, the memory write operation causes the data write of D ₁ corresponding to the addresses A _{0 to} A ₁₃ . When WE is LOW, the memory read operation outputs data from D ₀ corresponding to addresses A _{0 to} A ₁₃ .

Reference numeral 306 is a combining unit for combining the image data and the code pattern. The output D of the main scanning direction counter 301 and the output of the sub scanning direction counter 302 are input to the input D of the synthesizing unit 306, and the output of an EX-OR gate 307 for executing EX-OR (exclusive OR) logic processing. , The output line of the AND gate 308 which executes the AND logic processing with the output D _{0 of the} memory 305 is connected, and further, YMCK image data is input to IMGIN · YMCK to combine both input data and IMGO
It is configured to output from UT / YMCK. It should be noted that the synthesis by the synthesis unit 306 uses OR synthesis, addition synthesis, or another synthesis method. Alternatively, only a specific color (for example, yellow that is difficult to visually recognize) may be combined.

Next, the operation of the tracking pattern unit 209 will be described. First, before starting the copying process, pattern data is written in the memory 305 from a CPU (not shown). After that, when the copying process is started, the main scanning direction counter 3
01 and the sub-scanning direction counter 302 are used to read the pattern data stored in the memory 305. Further, when the LSBs of the main scanning direction counter 301 and the sub-scanning direction counter 302 input to the EX-OR gate 307 match, the input level becomes HIGH (the black portion shown in FIG.
H), the pattern combining is permitted, and the combining unit 306 executes the combining process on the image data with the pattern data in the memory 305 as a pattern.

FIG. 5 is an explanatory diagram showing the state of the pattern area of the memory 305, which has a size of 128 dots × 128 dots as shown in the drawing. Further, if the pattern data is data using alphanumeric characters or the like that can be easily identified by humans, the code is used as a pattern because it has an unfavorable influence on the original image data. By inputting the reference pattern into this code pattern as shown in FIG. 5, the pattern can be easily decoded. The reference pattern in this case is formed so as to be different from the code used for encoding.

Further, in the pattern printing, for example, as shown in FIG. 6, a 24-division area in which the main scanning direction is divided into 4 and the sub-scanning direction is divided into 6 is formed, and a code is written in this area. Depending on whether or not the pattern is formed, it is possible to form approximately 1.6 × 10 ⁷ patterns in 2 ²⁴ −1. Further, the number of identifiable items can be increased by increasing the types of the codes. Further, in the above, in the pattern having the directionality with respect to the reference pattern, the line width can be set to the minimum line width that can be discriminated.

When an operator makes an illegal copy, it is conceivable to execute printing a plurality of times. For example, if you copy the operation contents for the first time, copy prohibited items such as banknotes and securities,
Further, it is conceivable to reset the copied copy-prohibited object in the paper feed tray and perform copying with the original blank. In order to deal with such a case, misuse can be prevented by using a tracking pattern according to the present invention as shown in FIG.

That is, the tracking pattern can be discriminated by giving the pattern directivity. In addition, even if the patterns have the same directionality, the lines are printed with the thinnest possible line width. Therefore, the reference pattern is used as a reference by utilizing the fact that the printing positions are different for each copying process. It is possible to distinguish.

[0023]

As described above, according to the image forming apparatus with the tracking function according to the present invention, the image forming apparatus with the tracking function for executing the predetermined image processing on the image data read from the original and outputting the image. A pattern data storage means for storing a specific pattern having a reference pattern serving as a reference position of the pattern therein, and a synthesizing means for reading the specific pattern from the pattern data storage means and synthesizing the image data. Then, by clarifying the reference position indicated by the reference pattern part,
The pursuit work can be speeded up and ensured.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main configuration of an image forming apparatus with a tracking function according to the present invention.

FIG. 2 is a block diagram showing a schematic configuration of an image processing unit shown in FIG.

FIG. 3 is a block diagram showing a schematic configuration of a tracking pattern unit shown in FIG.

FIG. 4 is an explanatory diagram showing an example of synthetic input of pattern data according to the present invention.

FIG. 5 is an explanatory diagram showing a pattern area of a memory and a reference pattern example according to the present invention.

FIG. 6 is an explanatory diagram showing an example of a writing area of an encoding pattern according to the present invention.

FIG. 7 is an explanatory diagram showing a pattern example according to the present invention.

[Explanation of symbols]

 102 image processing unit 209 tracking pattern unit 301 main scanning counter 302 sub-scanning counter 303 selector 304 selector 305 memory 306 combining unit

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Claims (2)

[Claims] 1. A specific pattern in which a reference pattern serving as a reference position of the pattern is provided inside a pattern in an image forming apparatus with a tracking function that executes a predetermined image processing on image data read from a document and outputs an image. An image forming apparatus with a tracking function, comprising: a pattern data storage unit that stores the pattern data; and a synthesizing unit that reads a specific pattern from the pattern data storage unit and synthesizes it with the image data. 2. The image forming apparatus with a tracking function according to claim 1, wherein the specific pattern stored in the pattern data storage means is a directional pattern.