JP2001103278A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device that does not degrade image quality of an output image and discriminates specific information in the case of receiving image data with specific information written visibly or invisibly therein and printing it out in addition to substantial image information. SOLUTION: The image forming device detects presence of a trace pattern in an image of an original (S11), and when the trace pattern is detected (S12), zigzag area print control that is control to imbed the trace pattern in the image of the original and a newly added trace pattern separately into the image is conducted (S13). When no trace pattern is detected (S12), entire area print control that is control to imbed only the newly added trace pattern to the entire image area is conducted (S14).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus for printing out input image information, and in particular, in order to enable tracking of an output image, specific information is visually or invisiblely included in original image information. The present invention relates to an image creating apparatus that prints out a written image.

[0002]

2. Description of the Related Art Along with recent advances in digital signal processing technology, printing apparatuses and copiers for printing and outputting high-quality images have been developed. Copiers and the like that can obtain such high-quality images may be illegally used for the purpose of counterfeiting banknotes and securities.

Conventionally, various techniques for preventing such unauthorized use have been devised. For example, there is a technique in which a tracking pattern, which is information for tracking a situation when the image is copied, is input into an output image. The tracking pattern makes it possible to track the situation such as when and by which machine a copy was made. Information such as the machine name and serial number of the copying machine that copied the image and the date and time of the copy were recorded in a dot in a certain area. It is expressed as a pattern.

[0004]

However, according to the conventional tracking pattern driving technique, when a printed material on which the tracking pattern has been already recorded is further copied, the tracking pattern in the document and the tracking pattern to be newly added are not copied. However, there is a problem that image quality is deteriorated and tracking becomes impossible.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to input and print out image data in which specific information is written to the original image information in a visible or invisible manner. In this case, an object of the present invention is to provide an image creating apparatus capable of determining specific information without deteriorating the image quality of an output image.

[0006]

In order to solve the above-mentioned problems, an image creating apparatus according to the present invention provides an image forming apparatus which, when an input image includes specific information, compares the original specific information with specific information to be newly inserted. Are provided in the respective regions and driven into the image. More specifically, the image creating apparatus according to the present invention has the following configuration.

[0007] That is, the image forming apparatus according to the present invention comprises:
In an image forming apparatus that prints out an image in which specific information is written invisibly or hardly visible in original image information, an input means for inputting an image, and specific information (original information) written in the image from an input image. Means for detecting specific information of the image forming apparatus, and means for generating specific information (new specific information) which includes information unique to the image forming apparatus and which is newly written when the image forming apparatus prints out an image. And when the original specific information is detected by the detecting means, the original specific information and the new specific information are written in an invisible or hardly visible image into the input image by dividing the area, and When no specific information is detected, writing means for writing only new specific information invisibly or hardly visible to the entire input image, and printing for printing the input image in which the specific information is written And a stage.

In the image forming apparatus, the original specifying information may include information for distinguishing the original specifying information from the new specifying information.

The area into which the original specific information is to be input and the area into which the new specific information is to be input may be alternately provided in a staggered or checkered pattern.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a digital color copying machine as an embodiment of an image forming apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

The digital color copying machine of the present embodiment is a digital color copying machine that writes specific information (tracking pattern) invisible or hardly visible in a document image when copying the image of the document. When copying a document image containing specific information, the digital color copier separates the area of the original specific information contained in the document image from the specific information newly added at the time of copying. Write in the output image invisibly or hardly visible. This makes it possible for the original specific information and the new specific information to coexist without causing interference in the output image.

FIG. 1 is a sectional view showing the overall configuration of a digital color copying machine according to the present invention. The digital color copying machine is roughly divided into an image reader unit 100 for reading a document image and a copying unit 200 for reproducing an image read by the image reader unit 100.

The configuration of the image reader unit 100 is the same as the conventional one. Here, the scanner 10 includes an exposure lamp 12 for irradiating a document, a rod lens array 13 for condensing light reflected from the document, and a contact-type CCD color image sensor 14 for converting the collected light into an electric signal. ing.
The scanner 10 is driven by a motor 11 at the time of reading a document and moves in the direction of the arrow (sub-scanning direction).
5 scans the original placed thereon. The image of the document surface irradiated by the exposure lamp 12 is photoelectrically converted by the image sensor 14. R, G, obtained by the image sensor 14,
The multi-valued electrical signals of the three colors B are read by the read signal processing unit 20 into yellow (Y), magenta (M), cyan (C),
The data is converted to any of 8-bit grayscale data of black (K) and stored in the synchronization buffer (FIFO) 30.

Next, in the copying section 200, the print head section 31 performs gradation correction (γ correction) on the inputted gradation data in accordance with the gradation characteristics of the photosensitive member,
D / A conversion is performed on the corrected image data to generate a semiconductor laser drive signal, and the semiconductor laser is caused to emit light by the drive signal. The laser beam generated from the print head unit 31 by modulating the light emission intensity in accordance with the gradation data exposes the rotatably driven photosensitive drum 41 via the reflecting mirror 39.

The photosensitive drum 41 is irradiated by an eraser lamp 42 before receiving exposure for each copy, and is uniformly charged by a charging charger 43. When exposure is performed in this state, an electrostatic latent image of the document is formed on the photosensitive drum 41. Only one of the cyan, magenta, yellow, and black toner developing units 45a to 45d is selected to develop the electrostatic latent image on the photosensitive drum 41.

The developed toner image is transferred to a transfer charger 4
6 is transferred to the copy paper wound on the transfer drum 51. This printing process is repeated for four colors of yellow (Y), magenta (M), cyan (C), and black (K). At this time, the scanner 10 repeats the scanning operation in synchronization with the operations of the photosensitive drum 41 and the transfer drum 51.

Thereafter, the copy paper is separated from the transfer drum 51 by operating the separation claw 47, is fixed through a fixing device 48, and is discharged to a discharge tray 49.
The copy paper is fed by the paper cassette 50 and the leading end thereof is chucked by the chucking mechanism 52 on the transfer drum 51, so that no positional deviation occurs during transfer.

The digital color copier has an operation panel 16 on which a user makes various settings as shown in FIG.
It has. The operation panel 16 has a display panel section 16a for displaying a setting status, an operation state, and the like, and a plurality of keys such as a start key 16c for starting a copying operation and a ten-key 16h for setting the number of copies. .

(Read Signal Processing) FIG.
0 is a block diagram of FIG. Color CCD image sensor 1
The multi-valued electrical signals of the three colors r, g, and b obtained by (4)
First, after being amplified and optimized in the analog processing unit 320, the A / D conversion unit 321 outputs R, G,
Each of them is converted into a B multi-level digital signal. The digital signal output from the A / D conversion unit 321 is input to the shading correction unit 323 after being converted into serial data by the serial signal conversion processing unit 322.

In the shading correction section 323, RGB
The shading correction is performed based on the digital image data. The CCD image sensor 14 is composed of three lines of CCD sensors arranged at predetermined intervals, and each of the read RGB data has a timing shift.

The data subjected to the shading correction is corrected in the sensor window position correcting section 324 so that the timing shift is corrected and the data is synchronized. The RGB data subjected to the position correction is output to the reflectance / density conversion unit 325. At this time, the B data is also input to the tracking pattern detection processing unit 329. The tracking pattern detection processing unit 329 detects a tracking pattern that is specific information included in the document image. As described in the related art, the tracking pattern is a pattern in which information for identifying the source of a printed material such as a print date and time, a machine name of a copying machine, a serial number, and the like is constituted by dots of a predetermined color (generally yellow). is there. In the tracking pattern, such information can be read based on the arrangement of the dots.

When the tracking pattern is detected, the arrangement data of the tracking pattern is stored in the pattern memory 330, and the data is output to the print head unit 31 described later. The reflectance / density conversion unit 325 converts R, G, and B data, which are reflectance data, into DR, DG, and DB data that is 256 grayscale data.
The DR, DG, and DB data are output to the UCR / PB masking processing unit 326.

The UCR / BP masking processing unit 326 converts the DR, DG, and DB data into 256 density gradation data of cyan (C), magenta (M), yellow (Y), and black (K), and then converts the data to black. Processing to remove C, M, and Y data values from a black part (UCR processing) and to add black (K) gradation data (BP processing) in order to improve the reproducibility of Is applied.

Thereafter, a predetermined masking process is performed on the copy paper so as to reproduce the same color as that of the original in consideration of the reading characteristics of the CCD image sensor 14 and the adhesion characteristics of the toner to the copy paper, and then printing. Outputs color data according to the process. Data of any one of C, M, Y, and Bk output from the UCR / BP masking processing unit 326 is subjected to spatial filter processing such as smoothing and edge enhancement in the MTF correction unit 327.

The variable magnification movement processing section 328 includes the MTF correction section 32
Using the data from step No. 7, a scaling movement process is executed in accordance with the set copy magnification and the edited contents. The data output from the magnification change processing unit 328 is input to the print head unit 31 via a buffer. Print head 3
1 generates a semiconductor laser drive signal by D / A converting the input gradation data, causes the semiconductor laser to emit light by this drive signal, and exposes the photosensitive drum 41.

The print head unit 31 receives the image data sent from the read signal processing unit 20 and the data of the detected tracking pattern. The printer head unit 31 corrects the value of the driving level based on the value of the driving level of the actual tracking pattern recorded on the document, and drives the tracking pattern into the image data of the document with the corrected value of the driving level. . Thus, the tracking pattern can be driven at an appropriate level.

(Processing in Print Head Unit) FIG. 4 is a diagram showing a detailed configuration of the print head unit 31. The image data (8 bits) from the read signal processing unit 20 is passed through an interface unit 451 to a first-in first-out memory (hereinafter, referred to as a “FIFO memory”).
452. The FIFO memory 452 is a line buffer memory capable of storing gradation data of a predetermined number of lines in the main scanning direction, and operates between the image reader unit 100 and the copying unit 200 shown in FIG. It is provided to absorb the difference in clock frequency. F
The data in the IFO memory 452 is input to the tracking pattern generation and addition unit 453.

The tracking pattern generation and addition unit 453 adds a tracking pattern of a predetermined driving level sent from the printer control unit 401 to the image data. The process of adding a tracking pattern is executed by the printer control unit 401 according to a program stored in the control ROM 402. The layout data of the tracking pattern read from the image data of the document input from the pattern memory 330 of the reading signal processing unit 20 is stored in the reading tracking memory RAM 460 and input to the pattern matching unit 462.

The pattern matching unit 462 reads the tracking pattern arrangement data indicating the model name and serial number of the copying machine main body from the tracking information storage ROM 461, and compares the arrangement data with the tracking pattern arrangement data read from the image data of the document. Perform pattern matching. By this pattern matching, it can be determined whether or not the model that has created the original image is the same as the copying machine.

The print control unit 401 executes the setting process of the driving level of the yellow dot, and then outputs the set driving level value to the tracking pattern generation adding unit 453.

The gamma correction unit 454 includes a printer control unit 401
Tracking pattern generation and addition unit 4 based on the gamma correction data from
Correct the data from 53. Various gradation correction data (γ table, various correction values, etc.) are stored in the data ROM 403.
Is also stored. The data subjected to the γ correction by the γ correction unit 454 is converted to an analog voltage by the D / A conversion unit 456. This analog voltage is sent to the LD laser driver 457, and causes the laser diode 458 to emit light at the light intensity of that value.

(Process for Determining Arrangement Position of Tracking Mark) In the digital color copying machine according to the present invention, when copying a document image on which a tracking pattern has been recorded, a tracking pattern newly added when copying the document is provided. And the tracking pattern recorded in the document image are divided into respective regions and recorded in the output image.

FIG. 5 is a diagram for explaining a tracking pattern input area in an output image obtained by the digital color copying machine. As shown in the figure, the digital color copier has a document image 51 on which a tracking pattern has already been recorded.
Are read and copied to form an output image 53. In the output image 53, a region a (a hatched region of a stripe in the drawing) is a region where a new tracking pattern is to be driven.
And an area b (hatched area of dots), which is an area where a tracking pattern that has been applied to the document 51 is to be applied. These areas may be provided, for example, such that the areas a and b are arranged in a staggered pattern like the output image 53, that is, the areas are alternately shifted left and right for each row. Alternatively, they may be provided alternately in a checkered pattern like the output image 53 '.

FIG. 6 is a flowchart of a process for determining the arrangement position of the tracking pattern in the digital color copying machine. This process is controlled by the printer control unit 401 as follows. First, a tracking pattern is detected from a document image (S11). Details of this processing will be described later. When a tracking pattern is detected in the original image, FIG.
A staggered area print control is performed in which a tracking pattern of a document image and a tracking pattern to be newly driven as shown in the output images 13 and 13 'of FIG. If no tracking pattern is detected in the document image, the whole area printing control is performed in which only a new tracking pattern is applied to the entire image area (S1).
4).

FIG. 7 is a flowchart showing an example of processing for detecting a tracking pattern from an image of a document. In this example, a part of the image of the document (hereinafter, referred to as “block”) is investigated, and when a predetermined number or more of pixels that can form the tracking pattern are detected in the block, the tracking pattern is determined. Judge that there is.

Specifically, in FIG. 7, first, the counter N is set to zero (S111). It is determined whether or not the color of one pixel in some blocks of the image of the document is equal to the color yellow of the dots forming the tracking pattern (S112). If the pixel color is not yellow,
Proceed to step S115. If the color of the pixel is yellow, it is determined whether or not the size of the pixel is a predetermined size (S113). Here, the predetermined size is set to a size at which the pixel can be determined to be a dot constituting the tracking pattern. If the pixel has a predetermined size, the counter N is incremented. If the pixel is not the predetermined size, the process proceeds to step S115. Step S115
Then, it is determined whether or not the above inspection has been completed for all the pixels in the block. If the inspection has not been completed for all the pixels in the block, the process returns to step S112 and the above processing is repeated. When the inspection has been completed for all the pixels in the block, it is determined whether or not the counter N is larger than a predetermined value (S116). When the counter N is larger than the predetermined value, it is determined that the tracking pattern is detected (S
117). At this time, the tracking pattern is stored in a predetermined storage area. When the counter N is not larger than the predetermined value, it is determined that the tracking pattern has not been detected (S11).
8).

As a method for detecting a tracking pattern, the following method is also available. That is, a search area is set in the image area, and a pattern composed of yellow dots is extracted and stored in the search area. In this case, the search area may be shifted so as to scan the entire image, and after scanning the entire image, a common pattern may be detected as a tracking pattern from a plurality of stored patterns. Further, it can be detected by using other well-known image pattern recognition techniques.

Further, in the tracking pattern newly added by the digital copying machine of the present embodiment, information indicating that the tracking pattern is different from the tracking pattern read from the document may be provided. FIG. 8 is a diagram showing an example of a dot pattern of the tracking pattern. For example,
As shown in this figure, in the tracking pattern, areas X and Y are further provided in addition to the area A of the pattern including information such as the printing date and the machine name. In the area A, when the tracking pattern is the original tracking pattern in the document, the pattern read from the document is written, and when the pattern is a pattern to be newly added, the printing date, machine name, etc. Write a dot pattern indicating the information of Here, the area X is a flag area indicating that the tracking pattern is a pattern newly added when the image is created, and the area Y is included in the original image of the image having the tracking pattern. The flag area indicates that the pattern has been set. By referring to the presence or absence of dots in these areas X and Y, it can be determined whether the tracking pattern was originally added to the original of the image or newly added when the original image was copied.

In this embodiment, an example of application to a copying machine that reads a document image and prints out the read image has been described. However, the present invention receives image information via a network and prints the received image. The present invention can also be applied to an output printing device.

[0040]

According to the present invention, an area for inputting specific information to be newly added when copying and outputting an input image is separated from an area for inputting specific information included in the input image. Thereby, the specific information of the previous time and the specific information of the present time can be inserted into the image without interference. For this reason, more reliable and detailed tracking becomes possible.

[Brief description of the drawings]

FIG. 1 is a diagram showing an entire configuration of a digital color copying machine according to the present invention.

FIG. 2 is a diagram showing an operation panel of the digital color copying machine.

FIG. 3 is a block diagram of a read signal processing unit of the digital color copying machine.

FIG. 4 is a block diagram of a print head unit of the digital color copying machine.

FIG. 5 is a diagram illustrating a tracking pattern driving area in an output image.

FIG. 6 is a flowchart showing a process for determining a tracking pattern driving region.

FIG. 7 is a flowchart showing detection processing of a tracking pattern in a document.

FIG. 8 is a view for explaining a flag area for distinguishing types of tracking patterns.

[Explanation of symbols]

 Reference Signs List 10 scanner 16 operation panel 20 read signal processing unit 31 print head unit 100 image reader unit 200 copying unit 401 printer control unit

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C076 AA14 BA02 BA03 BA04 CA08 5C077 LL14 LL19 MM03 MP08 PP03 PP15 PP23 PP32 PP33 PP38 PQ22 RR01 SS02 SS05 SS06 TT06

Claims (3)

[Claims] 1. An image creating apparatus for printing out an image in which specific information is written invisibly or hardly visible in original image information, comprising: input means for inputting an image; Detecting means for detecting specific information (original specific information), and specific information that includes information unique to the image creating apparatus and is newly written when the image creating apparatus prints out an image (new identifying information). Information), and when the detection unit detects the original specific information,
The original specific information and the new specific information are written in an invisible or invisible manner in the input image by dividing the area, and when the original specific information is not detected by the detecting means, only the new specific information is input. An image creating apparatus, comprising: a writing unit for writing invisible or hardly visible on the entirety of an obtained image; and a printing unit for printing an input image in which specific information is written. 2. The image creating apparatus according to claim 1, wherein the new specific information includes information for distinguishing the original specific information from the new specific information. 3. The image creating apparatus according to claim 1, wherein an area in which the original specific information is input and an area in which the new specific information is input are provided alternately.