KR20120060742A - Micro pictures printing system, image forming method and printing method thereof - Google Patents

Abstract

PURPOSE: A microphotograph printing system, an image forming apparatus, and a printing method thereof are provided to generate a customized microphotograph on an electronic printing device. CONSTITUTION: A micro photo generating module(203) transmits a generated microphotograph to an image blending module(204). The image blending module performs a blending function of a printed page image. The image blending module transmits the blended image to a printing module(205). The printing module prints the blended image.

Description

Micro photo printing system, image forming apparatus and printing method thereof {Micro pictures printing system, image forming method and printing method

TECHNICAL FIELD The present invention relates to the field of digital micro printing for counterfeiting and copy protection of documents, and more particularly, to the generation and printing of personalized micro photographs on a home appliance printing apparatus.

Microprinting is mainly used to prevent counterfeiting of important documents and bills. Professional offset devices are used for this purpose. Recently, several approaches have been proposed for microcharacters or patterns with specific microstructures on relatively inexpensive home appliance printing devices.

US patent application US 20030021437 (Hersch et al) (Ecole Polytechnique Federale de Lausanne) discloses a method of protecting a printed document by printing additional images having a specific microstructure. Here, the image is generated from various elements such as text, graphics, and bitmaps having various shapes according to colors. This particular image is large enough and occupies a significant area on the page. There is no process for quickly creating such images and adjusting the image view for the user.

US patent application US 20070252838 (Hains et al) (Xerox) discloses a system and method for printing micro characters. Specific micro fonts based on PostScript Type 3 fonts are proposed. The main problem with using micro fonts is that they contain a fixed set of fixed symbols for some languages and need to be allowed.

The rapid generation of micro fonts from any font disclosed in US patent application 20090195210 based on Russian patent application 2008101807 makes it possible to overcome the aforementioned problems. The document illustrates a method of generating a symbol for microprinting, including a definition for each symbol of an image having an appropriate font size, taking into account small font generation rules. Thus, symbol rasterization is performed in the bitmap, the bitmap is skeletonized, reformatted to store symbols that the bitmap can understand, and cell halftoning is performed from the reformatted bitmap. Such applications can be considered the prototype of the present invention.

Each micro font needs to contain only a limited set of symbols. It is not easy to provide any image printing using the approach by the prior art [4]. Although theoretically possible, considerable effort requires a high degree of user qualification.

As described above, according to the related art, there is a problem in that it is not possible to provide a protection method for preventing copying on a home appliance copying device in the use of microtext.

The present invention is to provide a printing method and a system for automatically generating and adjusting micro-photographs on a home appliance printing device for preventing forgery and service, the technical problem.

The task can be achieved by two variants of the microphoto printing method and system and the method of generating micro photos from random images provided by the user, which are incorporated by the common inventive concept.

The technical problem is achieved by the development of a microphotographic printing method and system according to two variants for counterfeiting and copy protection, and also a method of generating a microphotograph from a random easy provided by a user.

In the first embodiment, the micro-photo printing system for counterfeit and copy protection,

An image registration module executed to register at least one image provided by a user and to transmit the at least one image to a micro photo generating module; A parameter adjustment module executed to function to adjust a parameter for blending the micro photograph with the micro photo generation parameter and the print page image, wherein the parameters are sent to the micro photo generation module and the image blending module; A micro picture generation module, the micro picture being sent to the image blending module, executed according to the parameters from the parameter adjustment module, to perform a micro picture generation function from the image obtained from the image registration module; An image blending module, which performs a blending function of at least one micro photographic and printing page image, obtained from an image registration module, wherein the blended image is sent to a printing module; And a printing module executed to perform a printing function of the blended image.

In the first embodiment, a method of printing a microphotograph for counterfeiting and copy protection includes: obtaining an image from a user; Generating a micro picture from the image, obtained from the user; Blending the micro picture with the print page image; And printing the blended image.

In a second embodiment, a microphotographic printing system for counterfeit and copy protection comprises: a microphotographic selection module, wherein the microphotographs are sent to an image blending module, executed to select at least one microphotograph from a set; A parameter adjustment module executed to make parameter adjustments for the blending of the micro picture and page image, the parameters being sent to the image blending module; An image blending module, wherein the blended image is sent to a printing module, which is executed to blend at least one microphotographic and page image, obtained from the microphotographic selection module according to the parameter from the parameter adjustment module; and It includes; print module is executed to print.

In the second embodiment, a method of printing micro photos for counterfeiting and copy protection,

Obtaining a micro photograph; Blending the micro picture with the print page image; Printing the blended image.

The method for generating a microphotograph from any image is connected with two embodiments according to the present invention, the step of detecting edges, the edge detection result having a dimension smaller than a few mm, and line-drawing Converting to a micro picture that looks like a picture.

The method and system according to the present invention may allow a user to create a micro picture from a random image and to print the micro picture blended with the print page image. These micro photographs become personalized marks.

1 is a view for explaining an example of using a micro-photograph for copy protection according to the present invention.
2 is a view showing the configuration of a micro-photo printing system for counterfeiting and copy protection according to an embodiment of the present invention.
3 is a view showing the configuration of a micro-photo printing system for counterfeiting and copy protection according to another embodiment of the present invention.
4 is a flowchart illustrating a microphoto printing method for counterfeiting and copy protection according to an embodiment of the present invention.
5 is a flowchart illustrating a microphoto printing method for counterfeiting and copy protection according to another embodiment of the present invention.
6 is a flowchart illustrating a method of generating a micro picture from a random image according to the present invention.
7 is a flowchart illustrating a method of generating a micro photo according to an exemplary embodiment of the present invention.
8 shows an example of an image histogram having a threshold value used for image contrast enhancement.
9 shows an example of a microphotograph (9.1) and an example (9.2) of which a microphotograph deteriorates due to copying.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

In a preferred embodiment, the invention can be implemented in a printer, for example a laser or inkjet or MFP. 1 shows an example of a microphotographic application for copy protection.

In order to generate a personalized copy protection mark, the user transmits the original photograph 102 to the printing apparatus 101 by the conventional method, i. , Parameters such as ink color for microphoto printing.

The microphotograph preferably has a height of 0.5 to 2.5 mm and the dimensions of the microphone photograph at the pixel depend on the print resolution. The micro picture 103 is automatically generated from the image provided by the user. The micro photograph 103 appears to be a miniature line drawing (sketch, draft) consisting of a small number of lines on a white background, the main line thickness being less than 80-86 μm (about 1/300 inch). This microphotograph is blended with the print page 104 at at least one selected location 105.

2 illustrates a configuration of a microphotographic printing system for counterfeiting and copy protection according to a first embodiment of the present invention.

The image registration module 201 registers at least one image provided by the user and transmits it to the micro picture generation module 203. The image registration module 201 may be implemented in the form of an image capture device such as a scanner or a camera, or in the form of a wired / wireless interface for data transmission, or a data storage device such as a flash memory or an HDD.

The parameter adjustment module 202 may adjust the parameters for the generation of the micro picture, the parameters for the blending of the micro picture and the print page image. At least, parameters for the number and location of micro photos on the page, the size of the micro photos, the color inks for micro photos printing, the line thickness in the micro photos, the image blending for the micro photos and the page images can be adjusted in the corresponding module. . The parameters are sent to the micro photo generation module 203 and the image blending module 204.

The micro picture generation module 203 generates a micro picture according to the parameter from the parameter adjustment module 202 from the image obtained from the image registration module 201. The micro picture is sent to the image blending module 204. The image blending module 204 blends the at least one micro photograph and print page image obtained from the micro photo generation module 203 according to the parameters from the parameter adjustment module 202. The blended image is sent to a printing module 205, which prints this image.

4 is a flowchart illustrating a microphotographic printing method for counterfeiting and copy protection according to a first embodiment of the present invention.

First, a random image having any size, any color depth, etc. is obtained from the user by camera or scanner means, image acquisition means via a wired / wireless interface, or by reading means from a storage device such as a flash memory or an HDD. (S401).

In a next step S402, a micro picture is generated from an image obtained from the user.

In the next step S403, the microphotograph is blended in the blending mode with the printed page image at the predefined position. In this case, the following blending modes are possible-the corresponding part of the page image is replaced by a micro picture. That portion of the page image is replaced with an invert micro picture. Performs a by-pixel logical OR operation on the micro photo and the page image part. Performs a by-pixel logical AND operation on the micro photo and the corresponding page image part. Performs a by-pixel logical XOR operation on the micro photo and the corresponding page image part.

In the last step S404, the blended image is printed.

The system and method according to the second embodiment of the present invention assumes that the user already has a micro photograph, for example a manually generated micro photograph.

3 illustrates a configuration of a microphotographic printing system for counterfeiting and copy protection according to a second embodiment of the present invention.

The micro picture selection module 301 selects at least one micro picture from the collection of micro pictures, and the micro picture is sent to the image blending module 303.

The parameter adjustment module 302 adjusts parameters for blending the micro picture with the page image, and these parameters are sent to the image blending module 303. Parameters for at least the number and position of the micro photos on the page, the color inks for printing the micro photos, and the blending mode of the micro photos and the page images can be adjusted in the corresponding module.

The image blending module 303 blends the at least one micro photograph and print page image received from the micro photo selection module 301 according to the parameters from the parameter adjustment module 302. The blended image is sent to the printing module 304.

The printing module 304 prints the blended image.

5 is a flowchart of a microphoto printing method for counterfeiting and copy protection according to a first embodiment of the present invention.

First, the micro picture is obtained from the user by the transmission of the micro picture through the wired / wireless interface or by reading means from a storage device such as, for example, a flash memory or an HDD (S501).

Subsequently, the microphotograph is blended according to the selected blending mode with the print page image at the predefined position (S502).

The possible blending modes are the same as the modes mentioned in the first embodiment described above.

In the last step S503, the blended image is printed.

All of these steps can be performed by various methods.

7 illustrates a method for generating a microphotograph in a preferred embodiment of the present invention.

Steps S701 to S704 correspond to step S601 of converting an edge image into a micro picture.

The original image is converted into a gray scale image in step S701. There are several ways to obtain gray scale images from color image elements (see, for example, the ADOBE PHOTOSHOP application: http://www.photoshopsupport.com/tutorials/cb/halftone.html site) [5]. The most popular method is the following equation (1).

Where r, g, b are the color channels of the original image.

In a given case, both of these approaches are possible, but the last is preferred.

Subsequently, the gray scale image is resized to the pixel size of the intermediate image (S702). The dimensions of the intermediate image are three times larger than the micro photograph. While any interpolation technique can be applied during resizing, bilinear interpolation can provide a suitable balance between image quality and computational complexity.

In a next step S703, contrast enhancement is performed. This is to make the microphotograph appear recognizable even in low contrast bitmaps.

The lower boundary of the contrast adjustment range is calculated according to the following equation.

Here, H0, C0, T are thresholds of histogram level, histogram area and histogram luminance, and threshold T is applied to avoid excessive image darkening.

The upper boundary of the contrast adjustment range is calculated according to the following equation (3).

Here, H1 and C1 are thresholds for the corresponding histogram luminance and region, and FIG. 8 shows these thresholds in one example of the luminance histogram.

Contrast adjustment The overall contrast enhancement is performed after the range calculation for the lower and upper portions.

Where (x, y) -the pixel coordinates of the intermediate bitmap,

I and I '- the contrast adjustment of the image before and after the intermediate

In step S704, the edges are detected in the intermediate bitmap. Several known edge detection methods can be applied, but the application of Diffrence-of-Gausians (DoG) filters with subsequent thresholds is desirable.

I is the intermediate bitmap of contrast adjustment, E is the edge image, T is the threshold, and * is the convolution. The difference-of-Gaussians filter parameters σ, σ 'and threshold T depend on the type of printing apparatus and the print resolution.

In a next step S705 the edge image is scaled down to the microphotographic M dimension, ie three times. For this purpose, image E is divided into 3 by 3 non-overlapped, and the following rules apply to each block. If the sum of pixels in the block is greater than 4, then the corresponding pixel in micropicture M is 1, otherwise it is 0, the corresponding pixel in micropicture M.

S706 is a process of removing an isolated pixel from the microphotograph M. FIG.

In the last step S707, the morphological filter of the extension is applied as a micro photograph. This operation is necessary for high resolution printing because too thin areas are not currently printed on the printing device during high resolution printing. Parameters such as aperture (structural element, mask) and the number of iterations for the morphological filter of the extension depend on the type of printing device and the print resolution.

9 shows an example of microphotograph 9.1 and microphotograph 9.2 deteriorated due to radiation. In this embodiment, the height of the printed microphotograph is about 2 mm. For illustration purposes, these images were scanned with an optical resolution of 2044 dpi.

10 is a diagram for describing a configuration of an image forming apparatus according to another exemplary embodiment.

According to FIG. 10, the image forming apparatus 1000 may include a control unit 1010, an image reading unit 1020, an output unit 1030, a user interface unit 1040, a storage unit 1050, a communication interface unit 1060, and the like. Data bus 1070.

The image forming apparatus 1000 according to FIG. 10 may be connected to an external device and output document data. The image forming apparatus 1000 may combine a printer, a scanner, a digital copier, a facsimile, or a combination thereof through a single device. It may be implemented in various forms such as a multifunction peripheral (MFP).

The controller 1010 functions to control overall functions of the image forming apparatus 1000. Accordingly, the controller 1010 may control various components included in the image forming apparatus 1000 described later. Herein, the controller 1010 may be implemented as a central processing unit (CPU).

In addition, the controller 1010 may provide preset parameters for the image blending process to the image processing unit 1030 which will be described later. Here, the preset parameters are among the parameters for the number and position of the security mark on the print target page, the size of the security mark, the color ink for printing the security mark, the line thickness in the security mark, and the blending mode of the security mark and the print target page. It may be at least one parameter.

In some cases, the controller 1010 may provide a parameter for generating a security mark from a security mark obtaining unit (not shown) which will be described later.

Here, the security mark may be implemented with the above-described micro photograph.

The image reading unit 1020 performs a function of reading a print target page by using an image sensor. In addition, the image reading unit 1020 may perform a function of scanning a specific image for obtaining a security mark.

The image reading unit 1020 may be embodied as a scan module (not shown) that specifically performs a scan operation.

The scan module (not shown) performs a scan operation under the control of the controller 1010 to be described later, and includes an image sensor unit (not shown), a motor unit (not shown), a position sensor unit (not shown), and a scan control unit ( Not shown).

The image sensor unit (not shown) includes a CIS sensor (not shown) for sensing an image to obtain an RGB pixel value corresponding to the image, and a scan control unit (not shown) which describes the RGB pixel value sensed from each position through the CIS sensor ( (Not shown).

The motor unit (not shown) transfers the document in the scan progress direction so that the RGB pixel value corresponding to the image formed on the document can be sensed in units of lines.

The position sensor unit (not shown) detects the position of the document fed into the image forming apparatus and transmits it to the scan controller (not shown). The scan controller (not shown) controls the image sensor (not shown), the motor (not shown), and the position sensor (not shown) to perform a scan operation according to a scan command received from the controller 1010 to be described later. To control. That is, the scan control unit (not shown) may combine the RGB pixel values sensed by the image sensor unit (not shown) to generate image data corresponding to the image formed on the document. Other descriptions of the scan operation will be omitted.

The image processing unit 1030 functions to perform image processing on input data under the control of the control unit 1010.

In detail, the image processing unit 1030 may perform image blending on the print target page scanned by the image reading unit 1020 and the security mark obtained by the security mark obtaining unit (not shown). In this case, the image processor 1030 may perform image blending using the preset parameters provided by the controller 1010.

The output unit 1040 serves to print and output the data processed by the image processing unit (not shown) on the recording medium under the control of the control unit 1010. In particular, the output unit 1040 may output an image in which the print target page image and the security mark are blended together by the image processing unit 1030. In this case, only one selected ink can be used for printing the micro photograph. For example, printing with yellow toner may produce copy protection marks that are hardly noticeable.

The user interface unit 1050 may include a display window such as an operation key (not shown) to which a user command for controlling an operation of the image forming apparatus 1000 is input and a liquid crystal display (LCD) for displaying a state of the image forming apparatus ( Not shown). In addition, the user interface unit 1050 may be implemented as a device in which input and output are simultaneously implemented, such as a touch screen display.

In addition, the user interface unit 1050 may display various information provided by the image forming apparatus 1000, progress of a job in progress in the image forming apparatus 1000, and a result thereof. The user may check various print jobs in the image forming apparatus 1000 through the user interface unit 1050 and may manage and control them.

In particular, the user interface unit 1050 may provide a user interface for adjusting the position and size of the micro picture on the printed page, a user interface for selecting the micro picture, and the like.

In this case, the original image may be input through the communication interface 1070 of the image forming apparatus 1000. Here, the communication interface unit 1070 supports data communication with an external device (not shown) through a network. For example, the communication interface unit 1070 may be implemented in the form of a wired or wireless communication module capable of supporting a DLNA network, a local method, a local area network (LAN), and an internet network. In addition, the external device (not shown) may be, for example, a host device such as a PC.

Alternatively, the original image can be executed by reading from the memory card through a card reader unit (not shown).

In addition, a hard copy of the original image may be scanned by the image reading unit 1020.

The original image may be stored in the storage 1060.

Here, the storage unit 1060 may be a storage medium in the image forming apparatus 1000 such as a memory or an HDD, an external storage medium, for example, a removable disk including a USB memory, a storage medium connected to a host, and a web through a network. It may be implemented as a server (Web server).

In particular, the storage unit 1060 may store a program code for generating a binary micro picture from the original image.

In some cases, the storage unit 1060 may store a plurality of preset security marks, and in this case, the security mark acquisition unit (not shown) may select at least one of a plurality of pre-stored security marks to obtain a security mark. You can get it.

Meanwhile, the controller 1010 replaces a predetermined portion of the print target page image with the security mark, replaces a predetermined portion of the print target page image with an invert security mark, and a corresponding portion of the security mark and the print target page image. To perform a by-pixel logical OR operation on, to perform a by-pixel logical AND operation on the security mark and the corresponding portion of the printable page image, and to a corresponding portion of the security mark and the printable page image The image processor 1030 may be controlled such that the print target page image and the security mark are blended together using at least one of operations for performing a by-pixel logical XOR operation.

Accordingly, the controller 1010 may execute a program code stored in the storage unit 1060 to generate a binary micro picture from the original image.

The data bus 1080 may support data transfer between modules of the system.

Meanwhile, in the present exemplary embodiment, the function of generating the micro picture is controlled by the components included in the image forming apparatus 1000. However, this is only an exemplary embodiment, and all of the above functions are described in the image forming apparatus 1000. Control may be controlled through a printer driver (not shown) or an application (not shown) included in the host device (not shown) connected to the control unit.

Meanwhile, in the present invention, as described above, a storage medium including a program for executing the printing method of the image forming apparatus according to an exemplary embodiment of the present invention may be included, that is, a computer-readable recording medium. Computer-readable recording media include all types of recording devices that store data that can be read by a computer system. Examples of computer readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disks, optical data storage devices, and the like, and computer readable recording media are distributed to networked computer systems so that the computer can be distributed in a distributed manner. Readable code can be stored and executed.

In addition, although the preferred embodiment of the present invention has been shown and described above, the present invention is not limited to the above-described specific embodiment, the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims. Of course, various modifications can be made by those skilled in the art, and these modifications should not be understood from the technical spirit or the prospect of the present invention.

210: image registration module 202: parameter adjustment module
203: Micro Photo Generation Module 203: Image Blending Module
205: print module

Claims (25)

In micro photographic printing system for counterfeit and copy protection,
An image registration module for registering at least one image provided by a user and transmitting the at least one image to a micro photo generation module;
A parameter adjustment module that adjusts the micro photo generation parameters and parameters for blending the micro photos with the print page image and sends the parameters to the micro photo generation module and the image blending module;
A micro picture generating module for generating a micro picture from an image provided by the image registration module and transmitting the generated micro picture to an image blending module according to the parameters received from the parameter adjusting module;
An image blending module which performs a blending function of at least one micro photograph and a print page image received from the image registration module according to the parameters received from the parameter adjusting module and transmits the blended image to a printing module; And
And a printing module for printing the blended image. The method of claim 1,
The parameter adjustment module,
Adjust at least one parameter of the number and position of the micro photos on the page, the size of the micro photos, the color ink for micro photos printing, the line thickness in the micro photos, and the blending mode of the micro photos and page images. Micro photo printing system. In the microphoto printing method for counterfeit and copy protection,
Receiving an image from a user;
Generating a micro picture from an image received from the user;
Blending the microphotograph with a print page image; And
And printing the blended image. The method of claim 3,
And the image received from the user is received via a wired or wireless interface. The method of claim 3,
And the image received from the user is received through a reading means of a storage device including a flash memory or an HDD. The method of claim 3,
And the image received from the user is received by an image capturing means including a scanner or a camera. The method of claim 3,
The micro photograph is,
Replacing the corresponding portion of the page image with the microphotograph;
Replacing the corresponding portion of the page image with an inverted micro photograph;
Performing a by-pixel logical OR operation on the corresponding portion of the microphotograph and the page image;
Performing a by-pixel logical AND operation on corresponding portions of the microphotograph and the page image; And
Performing a by-pixel logical XOR operation on the micro picture and a corresponding portion of the page image; And blended together with the page image using at least one of the following. In micro photographic printing system for counterfeiting and copy protection of originals,
A micro photo selection module for selecting at least one micro photo from the micro photo set and transferring the selected micro photo to an image blending module;
A parameter adjusting module for adjusting parameters for the micro photographs and page images, and transmitting the adjusted parameters to an image blending module;
An image blending module for blending at least one micro photo received from the micro photo selection module according to a parameter received from the parameter adjusting module and transmitting the blended image to a printing module; And
And a printing module for printing the blended image. The method of claim 8,
The parameter adjustment module,
And performing adjustments to at least one parameter of the number and position of micro photos on the page, ink colors for micro photos printing, and blending modes of micro photos and page images. In the microphoto printing method for preventing forgery and copying of an original,
Receiving a micro picture;
Blending the microphotograph with a print page image; And
And printing the blended image. The method of claim 10,
The micro photograph is,
Micro photographic printing method characterized in that it is received via a wired or wireless interface. The method of claim 10,
The micro photograph is,
And received by a reading means of a storage device including a flash memory or an HDD. The method of claim 10,
The micro photograph is,
Replacing the corresponding portion of the page image with the microphotograph;
Replacing the corresponding portion of the page image with an inverted micro photograph;
Performing a by-pixel logical OR operation on the corresponding portion of the microphotograph and the page image;
Performing a by-pixel logical AND operation on corresponding portions of the microphotograph and the page image; And
Performing a by-pixel logical XOR operation on the micro picture and a corresponding portion of the page image; And blending together with the print page image using at least one of the following. In the micro photo generation method for generating a micro photo from a random image,
Detecting contour differences; And
And converting the contour image into a micro photograph having a dimension in mm and similar to a pencil sketch. The method of claim 14,
Detecting the contour difference,
Converting the original image to a gray scale bitmap;
Resizing the bitmap to a medium size;
Improving the contrast of the intermediate bitmap; And
And detecting the contour difference on the intermediate bitmap. 16. The method of claim 15,
And the original image is converted into a gray scale bitmap using one of the following equations. The method of claim 16,
The method and the threshold value of the difference-of-Gaussians (DOG) filter is dependent on the type of printing device and the print resolution. The method of claim 14,
The contour difference,
A method for generating a microphotograph, characterized in that it is detected by a difference-of-gaussians (DOG) filter means having subsequent thresholding. The method of claim 14,
Converting the contour image into a micro picture,
Downscaling the edges to micro photo size;
Removing isolated pixels from the microphotograph; And
And applying a morphological extension filter to the microphotograph. 20. The method of claim 19,
The parameters of the morphological extension filter depend on the type of printing device and the print resolution. In the image forming apparatus,
An image reading unit which scans a page to be printed;
A security mark acquisition unit obtaining at least one security mark;
An image processor configured to perform image blending by applying preset parameters to the scanned printing target page and the security mark;
A control unit which provides the preset parameter to the image processing unit; And
And an output unit configured to output an image blended by the image processing unit. The method of claim 21,
The control unit,
Parameters for the number and position of the security mark on the print target page, the size of the security mark, the color ink for printing the security mark, the line thickness in the security mark, and the blending mode of the security mark and the print target page. And adjusting at least one of the parameters to be provided to the image processing unit. The method of claim 21,
The image reading unit,
Scan a specific image and provide it to the security mark acquisition unit;
The security mark acquisition unit,
And obtaining the at least one security mark from the scanned image. The method of claim 21,
Further comprising: a storage unit for storing a plurality of predefined security marks,
The security mark acquisition unit,
And selecting the at least one security mark from among the plurality of security marks. The method of claim 21,
The control unit,
Replacing the predetermined portion of the print target page image with the security mark, replacing the predetermined portion of the print target page image with the invert security mark, and by the security mark and the corresponding portion of the print target page image by performing a -pixel logical OR operation, performing a by-pixel logical AND operation on the corresponding portion of the security mark and the print target page image, and a corresponding portion of the security mark and the print target page image And controlling the image processing unit to blend the print target page image and the security mark together using at least one of an operation of performing a by-pixel logical XOR operation.

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