JP2002023572A - Device and method for making paper for copy forgery prevention - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device and a method which can obtain paper for copy forgery prevention of specific quality irrelevantly to the resolution of an image forming device while shortening a processing time and reducing the amount of data. SOLUTION: A form information preparation part 1 sends drawing information including two kinds of definition parts of a pattern which can be resolved by a copying machine and a pattern which can not be resolved by the copying machine, a procedure part for filling a page with one pattern, a procedure part which paints out the inside of a specific path in a color forming no image, a procedure part, which generates a drawing clip state in the same specific path, and a procedure part which fills the page with the other pattern in the drawing clip state as drawing information for making a form for copy forgery prevention to an image formation part 3. The image formation part 3 performs drawing processing according to the received drawing information, so that the form for copy forgery prevention can be made.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-counterfeiting paper generating apparatus and an anti-counterfeiting paper generating method for generating anti-counterfeiting paper in which a hidden pattern appears when copied.

[0002]

2. Description of the Related Art Conventionally, special paper called copy forgery prevention paper has been used in order to suppress unauthorized copying of confidential documents. The copy forgery prevention sheet is a sheet on which a special pattern which is hard to be seen by human eyes, but in which warning characters and the like which are hidden when copied by a copying machine emerges is printed in advance. When a document printed on this copy forgery prevention paper is copied by a copier, warning characters such as "copy prohibited" appear prominently on the copy, so that psychological protection against the act of illegally copying is made. This is a deterrent and also makes it possible to distinguish between the original and the copy.

[0003] Such a copy forgery prevention sheet is often preliminarily subjected to special printing. For this reason, the cost of the paper itself is higher than the paper used in ordinary copiers and printers, and when changing the design of background patterns, logos, symbol marks, etc., it is necessary to start over from paper printing, There is a problem that costs are increased. Further, such printed matter must be stored strictly, which requires labor and cost.

In recent years, it has been considered to generate copy forgery prevention paper in the image forming apparatus by utilizing the fact that the resolution of the image forming apparatus is higher than the reading resolution of the copying machine. Such a method of producing a copy forgery prevention sheet is described in, for example, Japanese Patent Application No. 11-312772 and Japanese Patent Application Laid-Open No. 7-231384. In these methods, two types of halftone generation processing are performed on the background image data of the copy forgery prevention paper such that one is resolvable by a copier and the other is not resolvable, and is separately prepared. In accordance with the pixel value of the binary image mask data representing the latent image to be embedded, one of the halftone dot generation processing image data is selectively output.
When the copy forgery prevention sheet output in this manner is copied by a copying machine, only the halftone dot-processed image data portion resolvable by the copying machine, that is, only the portion representing the latent image of the mask data is resolved and copied. As a result, a warning character or the like appears as a result, which is useful for deterring illegal copying and tracking the source.

In the above-described method, the copy forgery prevention paper generation process requires access to a large amount of image data, such as two types of halftone dot generation processes and mask reference at the time of selective output. Is very large. In particular, when processing is performed by software, there is a problem that the processing time becomes longer.

Further, since the copy forgery prevention paper data to be generated is also image data, the data size becomes large. For this reason, when a plurality of copy forgery prevention paper data are stored and can be selected at the time of use, the capacity of a necessary storage device increases, and a load when transmitting the copy forgery prevention paper data through a network is large. There is a problem.

Further, when the resolution of the output device is different,
It is necessary to prepare large-sized copy forgery prevention paper data for each different resolution. By enlarging the background image data and mask data when the copy / forgery prevention paper data becomes necessary, the size problem may be reduced somewhat, but in that case, the outline data of the latent image data to be embedded is reduced. There is a problem that the image is deteriorated by the enlargement processing. Conversely, if reduction processing is performed in response to a low-resolution output device, the latent image data itself is also erased as noise,
There is also a problem that it does not become a copy forgery prevention paper.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and reduces processing time and the amount of data. Also, the present invention provides a copy forgery prevention paper of a predetermined quality regardless of the resolution of an image forming apparatus. It is an object of the present invention to provide a copy forgery prevention paper generating apparatus and a copy forgery prevention paper generation method capable of obtaining the following.

[0009]

According to the present invention, two types of defined portions, a pattern resolvable by a copying machine and a pattern unresolvable by a copying machine, are used as drawing information used for generating copy forgery prevention paper. A procedure portion for filling the page with one pattern, a procedure portion for filling the designated path with a non-image-formed color, a procedure portion for generating a drawing clip state using the same designated path, Drawing information including a procedure portion that fills the page with the other pattern under the clip state is used. Such drawing information is stored in, for example, a PDL (Page
The image data can be described in terms of Pt. Language, etc., and the data amount can be remarkably reduced as compared with the conventional image data such as a bit map. Further, the processing amount can be significantly reduced as compared with accessing image data such as a bitmap many times. Further, since such drawing information is a description that does not depend on the resolution of the image forming means, by generating copy forgery prevention paper based on this drawing information, a predetermined number of sheets can be obtained regardless of the resolution of the image forming means. It is possible to obtain high-quality copy forgery prevention paper.

The designated path for embedding the latent image is
For example, basic paths are arranged according to specific rules, such as keeping the horizontal interval and vertical interval of a plurality of basic paths arranged on a page at a fixed interval, or a specific font of a specific font Specific character string outline data represented by the size can be used. The two types of patterns can be determined based on the specific background color of the copy forgery prevention paper to be generated.
The parameters relating to these designated paths, the background color of the copy forgery prevention paper, and the like can be designated by the user.

Further, a plurality of drawing information as described above may be held in the image forming means, and the held drawing information may be selected according to an instruction. Since the drawing information has a small data amount as described above, the drawing information corresponding to a plurality of copy forgery prevention sheets can be held with a small storage capacity.

[0012]

FIG. 1 is a block diagram showing an embodiment of a copy forgery prevention sheet generating apparatus according to the present invention. In the figure, 1 is a paper information generation unit, 2 is a parameter designation unit, and 3 is an image forming unit. The paper information generation unit 1 generates drawing information for forming an image of the copy forgery prevention paper in accordance with an instruction from the parameter specification unit 2. This drawing information includes two types of defined portions, a pattern that can be resolved by the copying machine and a pattern that cannot be resolved by the copying machine, a procedure portion that fills the page with one pattern, and an image forming process within the designated path. The procedure includes a procedure for painting with a color that is not performed, a procedure for generating a drawing clip state using the same designated path, and a procedure for filling the page with the other pattern under the drawing clip state. Details will be described later.

The designated path for embedding the latent image is
For example, the basic paths may be arranged in accordance with a specific rule such that a horizontal interval and a vertical interval between a plurality of basic paths arranged on a page are fixed. If the interval between the basic paths is too small, the latent image or other parts may be crushed, and the meaning of the designated path may be lost. The specified path may be specific character string outline data expressed by a specific font size of a specific font. For example, a character string such as "prohibited copying" can be designated as a latent image or a portion other than the latent image. Further, the two types of patterns to be embedded in the latent image or other portions can be determined based on the specific background color of the copy forgery prevention paper to be generated. Even if the same pattern is used, the latent image may be more conspicuous depending on the color of the background color, and it is preferable to determine a pattern that makes the latent image less conspicuous as much as possible according to the background color.

The parameter specifying unit 2 includes various rules relating to the specified path, such as a specific rule for arranging a basic path as described above, a character string, a font, and a font size when arranging a character string. It is provided for the user to specify the background color of the copy forgery prevention paper or the like. If such designation is unnecessary, the parameter designation section 2 is not required.

The image forming section 3 receives the drawing information sent from the sheet information generating section 1, performs a drawing process according to the drawing information, and forms an image on a sheet. This makes it possible to obtain copy forgery prevention paper. The drawing process is performed in accordance with the resolution at the time of image formation by the image forming unit 3, and an image for preventing copy forgery that is optimal for the resolution is generated.

Next, the operation of the copy forgery prevention paper generating apparatus according to an embodiment of the present invention will be described. The paper information generation unit 1 follows the instruction from the parameter specification unit 2 and
The drawing information for forming an image on the copy forgery prevention paper is generated, and the generated drawing information is transferred to the image forming apparatus. Upon receiving the drawing information, the image forming unit 3 performs a drawing process according to the drawing information, forms an image for preventing copy forgery, and generates a copy forgery prevention sheet. At this time, the image forming unit 3
Then, the drawing process is performed according to the configuration of the drawing information. Therefore,
The paper information generating unit 1 generates drawing information in the order of the drawing process in the image forming unit 3, and the image forming unit 3 performs the drawing process in the order. Hereinafter, a process of processing the drawing information for generating the copy forgery prevention paper will be described. However, as described above, the paper information generating unit 1 may generate the drawing information so that the processing described below is performed. Good.

FIG. 2 is a flowchart showing an example of a process for generating an image to be formed on a copy forgery prevention sheet, and FIG.
7 are explanatory diagrams of specific examples of images generated at each stage, and FIG. 8 is an explanatory diagram of an example of an image obtained when the generated copy forgery prevention paper is copied by a copying machine. In the following description, the drawing information is assumed to be PDL, and in this case, PostScript (registered trademark) is used as an example. Of course, the same applies to other PDL and drawing information other than the description in PDL.

First, in step S11, information relating to an output page required in subsequent processing is acquired. PostScri
In the case of pt, a command for that is issued to the PostScript interpreter. The output page information includes a page size, a resolution, and the like.

In step S12, two types of patterns, ie, a pattern that can be resolved when copied by a copying machine and a pattern that cannot be resolved, are defined. The pattern defined here is used in the subsequent processing. In PostScript, it is defined as readable image data. The specific data of this pattern is arbitrary as long as one is resolvable when copied by a copier and the other is not resolvable,
Usually, it is generated by a different halftone dot generation process. As a typical example, the resolvable pattern can use a method in which generated halftone dots are relatively large, such as dot concentration type dither. For the unresolvable pattern, a method that generates relatively small halftone dots, such as an error diffusion method, can be used. Since the halftone generation processing only needs to be performed on the background image data having the pattern size described below, the processing load is very small as compared with the processing on the entire page. When the background is a single color, there is no need to prepare background image data. In addition,
The pattern may be image data (a sequence of pixel values of each pixel), binary mask data, or a command to draw a halftone dot.

The pattern size is such that even if the pattern is repeated and the page is completely filled, the repetition is visually inconspicuous. Increasing the pattern size makes repetition less noticeable, but increases the size of the image data that must be stored as drawing information, thereby achieving the intended purpose of reducing the amount of drawing information data. Will be gone. If the size of the pattern is reduced, the possibility that the repetition of the pattern is visually conspicuous increases, and the development (pattern drawing in a page) time in the PostScript interpreter increases. An appropriate pattern size may be determined from the balance between the two. The pattern size is width, height,
The two types of patterns can be determined independently.

If the dots in the pattern depend on the resolution (such as the dot interval generated by dithering), a different pattern is defined according to the resolution, and S13 described below.
In the pattern drawing of S16, it is also possible to perform the drawing process by switching the pattern depending on the resolution. Even if several patterns are defined, the data amount does not increase so much if the pattern size is small.

In S13, a drawing process is performed to fill the page using one of the two types of patterns defined in S12. Depending on which pattern is used, the pattern appearing when copied on the finally generated copy forgery prevention paper is reversed. For example, this S1
In step 3, when a pattern that cannot be resolved when copied by a copying machine is used, when the generated copy forgery prevention paper is copied by the copying machine, a figure drawn by a designated pass described below appears. Conversely, when the pattern resolvable in S13 is used, if the generated copy forgery prevention paper is copied by the copying machine, the figure drawn by the designated pass described below becomes blank.

In order to fill the inside of a page with a pattern, the number of patterns (the number of rows and the number of columns) required to fill the page is determined from the resolution and the page size, and the patterns are drawn one by one while changing the base point coordinates. I just need. As a result, the same drawing information can be output to image forming apparatuses having different resolutions. In the case of PostScript, if the data of the pattern defined in S12 is image data,
The image can be drawn by an image operator or a color image operator. When the pattern data is binary mask data, the color value to be drawn is setcmykco.
imagemas after setting with lor operator etc.
Drawing is possible using the k operator. However, since the generated drawing data needs to be output directly from the output device, the pixel value of the halftone dot is set to 0 or 255 in the case of 1 byte per pixel, 0 or 1 in the mask data, and Must be specified by YMCK.

Instead of generating a command to draw a pattern one by one, a pattern is used for the color value (Post
In Script, a rectangle representing a page can be completely filled with a make operator or a fill operator.

FIG. 3 shows a page image at this stage. The broken lines indicate the boundaries of the patterns for convenience.
In the example, the pattern is drawn in 4 × 6. The lowermost pattern in this is half the height. This indicates that the drawn pattern is not actually printed because it is out of the page area.

In step S14, the area surrounded by the designated path representing the latent image to be embedded is white (color in which no image is formed).
Fill with. At this time, all the paths to be arranged on the page may be specified, or a basic path may be specified and the specified path may be repeatedly arranged on the page according to a specific rule. . If the designated path is a character string, the same function can be realized by drawing the character string in white (color in which no image is formed) in accordance with the specification of the font, font size, and the like.

FIGS. 4 to 6 show examples of filling a designated path. The example shown in FIG. 4 is an example in which a star-shaped designated path is painted in white. FIG. 5 shows a character string of “prohibition copy” drawn in white. Further FIG.
Are repeatedly drawn according to a specific rule using the character string of “forbidden copy” as a basic pattern. The rules used in FIG. 6 include the interval between character strings (the horizontal interval when one character string is drawn and then the next character string is drawn) and the interval between character strings (between vertical character strings). Distance)
Is set to a predetermined value. In each drawing, the thin line indicating the designated path is shown for convenience, and is not included in the actual output image. The same applies to the following figures.

In this case, the path designation of the latent image pattern is P
Since this is exactly the path specification in ostScript, it does not depend on the resolution. That is, even when the resolutions of the image forming units 3 are different, good image quality can be obtained without preparing data for each resolution of each image forming unit. In particular, in the case of a character or the like, jaggies may occur when the character outline is held as image data such as a bitmap and enlarged or reduced according to the resolution.
Such a problem does not occur in the case of filling by the designated path as described above. In the case of characters, the font and font size are arbitrary and can be easily selected.

S15 to S17 are a series of processing. S1
In step S5, a clip state is generated by the exactly same path as the designated path used for filling in S14. Continue to S16
In step S13, a drawing process is performed to fill the entire page in the same manner as the pattern drawing in step S13, using a pattern different from the pattern used in step S13. If the clip state is not generated in S15, the page is filled with the pattern as in the case of the pattern drawing in S13, but since the clip state is in the designated path, the pattern is drawn only in the clip. Become. Finally, in S17, the clip state is released for the subsequent processing, for example, processing for drawing desired document data on copy forgery prevention paper.

FIG. 7 shows an example of a copy forgery prevention image finally drawn. FIGS. 7B to 7D show the result of filling the area clipped by the designated path using the pattern shown in FIG. 7A. Figure 4
6 to FIG. FIG. 8 also shows FIG.
9 shows an example of an image when the copy forgery prevention sheet on which the image shown in FIG. FIG.
(A) shows a case where a pattern that cannot be resolved when copied by a copying machine is used as the pattern to be drawn in S13, and the portion of the designated path is lost in white. FIG. 8B shows a case where a pattern resolvable when copied by a copying machine is used as the pattern to be drawn in S13, only the designated path portion appears, and the other portions are white. . In either case, characters that are inconspicuous on the copy forgery prevention paper will appear when copied. In this manner, forgery using a copying machine can be prevented. Since appearing characters and the like are drawn using the designated pattern, jaggies and the like do not occur in the outline thereof, and the images are reproduced with good image quality.

The paper information generating section 1 generates drawing information so that the above-described drawing processing is performed in the image forming section 3. That is, two types of defined portions (corresponding to S12) of a pattern that can be resolved by a copying machine and a pattern that cannot be resolved by a copying machine, a procedure portion (corresponding to S13) that fills a page with one pattern, and A procedure part (corresponding to S14) for painting the designated path with a color that does not form an image, and a procedure part (corresponding to S15) for generating a drawing clip state with the same designated path. It is sufficient to generate drawing information including a procedural part (corresponding to S16) that fills the page with this pattern. Then, the image forming unit 3 executes the above-described drawing process only by performing the drawing process in accordance with the sent drawing information, and can generate the copy forgery prevention paper.

When data for generating copy forgery prevention paper is provided as image data such as a bitmap as in the conventional case, a data amount of about 4 Mbytes is required for a 600 dpi / A4 monochrome image (either YMCK). Had become. However, in the present invention, the pattern size is 256 × 25.
In the case of 6 pixels, the size of the copy and forgery prevention paper data is 16K bytes or less, which is 1/100 or less.

As described above, since the data amount is reduced, the processing for generating the drawing information for the copy forgery prevention paper in the paper information generating unit 1 can be speeded up. Transfer to the server can be performed in a short time. Therefore, for example, even when the drawing information of the copy forgery prevention paper is transferred using a network or the like, the transfer can be performed without imposing too much load on the network. Even if the resolution of the image forming unit 3 is different, it is not necessary to change other than the two types of patterns. Even if the two types of patterns are prepared for different resolutions, the data amount does not increase so much. .

FIG. 9 is a block diagram showing a modification of the embodiment of the copy forgery prevention sheet generating apparatus of the present invention. In the figure, the same parts as those in FIG. Reference numeral 4 denotes a drawing information storage unit. As described above, since the drawing information for generating the copy forgery prevention paper has a much smaller data amount as compared with the related art, for example, the drawing information of several types of copy forgery prevention paper is stored in the drawing information storage unit 4. I can put it. Even if the drawing information of several types of copy forgery prevention paper is stored, not much storage capacity is required. Then, for example, a copy forgery prevention sheet to be used is instructed from an operation panel provided in the image forming unit 3, or a command for designating the copy forgery prevention sheet is received from the outside, and the copy forgery prevention sheet is generated according to the instruction or the command. Can be configured. In this case, security should be ensured so that the copy forgery prevention paper cannot be obtained illegally.

[0035]

As is apparent from the above description, according to the present invention, since the image of the copy forgery prevention paper is described by the drawing information such as PDL, it is possible to shorten the processing time for generating the drawing information and to reduce the data processing time. The size can be greatly reduced. Further, it is possible to generate drawing information for copy forgery prevention paper that does not depend on the resolution, and there is an effect that good results can be obtained in terms of image quality.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an embodiment of a copy forgery prevention sheet generating apparatus according to the present invention.

FIG. 2 is a flowchart illustrating an example of a process for generating an image to be formed on a copy forgery prevention sheet.

FIG. 3 is an explanatory diagram of a specific example of an image generated when a page is filled with one pattern.

FIG. 4 is an explanatory diagram of a first specific example of an image generated at the stage of filling with a designated path.

FIG. 5 is an explanatory diagram of a second specific example of an image generated at the stage of filling with a designated path.

FIG. 6 is an explanatory diagram of a third specific example of an image generated at the stage of filling with a designated path.

FIG. 7 is an explanatory diagram of a specific example of an image of a copy forgery prevention sheet finally generated.

FIG. 8 is an explanatory diagram of an example of an image obtained when the generated copy forgery prevention paper is copied by a copying machine.

FIG. 9 is a block diagram showing a modification of the embodiment of the copy forgery prevention sheet generating apparatus of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Paper information generation part, 2 ... Parameter designation part, 3 ... Image formation part, 4 ... Drawing information storage part.

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 2C061 AP01 AP04 BB17 CL10 2C087 AA09 BA03 BA09 BC07 DA13 2H034 FA03 5C076 AA02 AA14 AA16 AA18 AA35 AA40 BA02 BA06 5C077 LL14 LL18 MP02 NN08 NN11 NN19 PP19 PP23

Claims (8)

[Claims] In a copy forgery prevention paper generating apparatus, comprising a paper information generating means and an image forming means, wherein the image forming means generates copy forgery prevention paper, the paper information generating means can be resolved by a copying machine. Two types of definition parts, a pattern and a pattern that cannot be resolved by a copier, a procedure part that fills the page with one pattern, and a procedure part that fills the designated path with a color that does not form an image on it, A drawing part including a procedure part for generating a drawing clip state in the designated path and a procedure part for filling the inside of the page with the other pattern under the drawing clip state are sent to the image forming unit, and the image forming unit includes: Receiving the drawing information, performing a drawing process, and forming an image to obtain a copy forgery prevention sheet; apparatus. 2. The copy forgery prevention sheet generating apparatus according to claim 1, wherein the designated path is obtained by arranging a basic path on a page according to a specific rule. 3. The specific rule according to claim 2, wherein the specific rule is to make a horizontal interval and a vertical interval between a plurality of basic paths arranged on a page a constant interval. A copy counterfeit prevention paper generator. 4. The apparatus according to claim 1, wherein the specified path is specific character string outline data represented by a specific font size of a specific font. A copy counterfeit prevention paper generator. 5. The copy forgery according to claim 1, wherein the two types of patterns are determined based on a specific background color of the copy forgery prevention paper to be generated. Prevention paper generation device. 6. The paper information generating means according to claim 1, wherein said paper information generating means includes a specifying means for specifying a parameter relating to said specified path or a background color of a copy forgery prevention paper by a user. 6. The copy forgery prevention paper generating apparatus according to claim 1. 7. The image forming apparatus according to claim 1, wherein the image forming unit is capable of holding a plurality of pieces of the drawing information, and forms an image by selecting the held drawing information in accordance with an instruction. A copy forgery prevention paper generating apparatus according to any one of the preceding claims. 8. A pattern part that can be resolved by a copying machine and a pattern part that cannot be resolved by a copying machine, a procedure part that fills a page with one pattern, and an image in the designated path. Drawing information including a procedure part for painting with a color that is not formed, a procedure part for generating a drawing clip state in the same designated path, and a procedure part for filling the page with the other pattern under the drawing clip state A copy forgery prevention sheet generating method, wherein an image generated by transferring and executing the drawing information is formed on a sheet to generate a copy forgery prevention sheet.