JP2011086973A - Image processing apparatus, image forming apparatus, image processing program, decoding document printing medium, and decoded document printing medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a decoded document printing medium so that contents of an original document cannot be read without superposing a decoding document printing medium, from the original document. <P>SOLUTION: Encrypted document data 63 is generated, based on filter data 62 which have a plurality of patterns each sequentially formed of four unit images and in which each of the patterns is formed of a white image as one unit image (transmission part) and predetermined images as other three unit images, and image data 61 of the original document. An image of the original document existing at a position corresponding to a transmission part is provided at a corresponding position of an image of the encrypted document data 63 when an image of the filter data 62 and an image of the original document are superposed with each other, and an image, in which at least density in the density and hue is adjusted according to an image of the transmission part, is provided at image positions of the encrypted document data 63 corresponding to positions of the other three unit images. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image processing apparatus, an image forming apparatus, an image processing program, a decrypted document print medium, and a decrypted document print medium.

  Patent Document 1 discloses a technique that allows a designated area portion to be made unreadable (encrypted in a mosaic pattern or the like) by specifying a print area in which information that is not to be leaked is described. Yes. With this technique, an output document including an unreadable part can be scanned as an input original, and an image in which the unreadable part is restored to the original image can be printed. With this technology, if a sheet on which an unreadable portion is restored to the original image and printed is transferred to a third party, information will eventually leak. Further, in order to decode information, it is necessary to perform scanning processing using an output document including an unreadable part as an input document. Furthermore, paper is consumed twice for information encryption and decryption.

Japanese Patent Laid-Open No. 06-098153

  An object of the present invention is to generate a decrypted document print medium in which the contents of the original document cannot be read unless the decrypted document print medium is superimposed on the original document.

  According to the first aspect of the present invention, a plurality of patterns each consisting of a plurality of unit images are continuously formed, and each of the patterns is an image in which some of the unit images are white images and other unit images are predetermined. And generating means for generating third image data based on the first image data of the image formed in step S2 and the second image data of the original document, and the generating means includes the first image data Providing an image of the second image data at a position corresponding to the white image when the image of the data and the image of the second image data are overlaid at a corresponding position of the third image data; In the image processing apparatus, an image whose density is adjusted according to the partial unit image is provided at a position of the third image data corresponding to a predetermined image.

  According to a second aspect of the present invention, a plurality of patterns each consisting of a plurality of unit images are formed continuously, and each of the patterns is an image in which some of the unit images are white images and other unit images are predetermined. And generating means for generating third image data based on the first image data of the image formed in step S2 and the second image data of the original document, and the generating means includes the first image data Providing an image of the second image data at a position corresponding to the white image when the image of the data and the image of the second image data are overlaid at a corresponding position of the third image data; In the image processing apparatus, an image whose density and hue are adjusted according to the partial unit image is provided at a position of the third image data corresponding to a predetermined image.

  According to a third aspect of the present invention, in the image processing apparatus according to the first or second aspect, the generation unit is based on the first image data in which the position of the white image in each pattern is irregular. Then, the third image data is generated.

  According to a fourth aspect of the present invention, in the image processing device according to any one of the first to third aspects, the generation unit includes an image of the first image data and an image of the second image data. Are placed at the corresponding positions of the third image data, and the images of the second image data at the positions corresponding to the white images are superimposed at a predetermined positional relationship. An image with density and hue adjusted according to the partial unit image is provided at the position of the third image data at a position corresponding to the image.

  According to a fifth aspect of the present invention, in the image processing device according to any one of the first to fourth aspects, the generation unit uses the plurality of types of the second image data to generate the first image. When the data image and the second image data image are superimposed, the second image data image at a position corresponding to the white image is overlapped between the plurality of types of the second image data. It is provided at the corresponding position of the third image data so that it does not.

  According to a sixth aspect of the present invention, a plurality of patterns each consisting of a plurality of unit images are formed continuously, and each of the patterns is an image in which some of the unit images are white images and other unit images are predetermined. Generating means for generating third image data on the basis of the first image data of the image formed by the second image data of the original document, the first image data, and the third image data Image forming means for forming an image on a print medium based on each of the image data, wherein the generating means superimposes the image of the first image data and the image of the second image data The third image data corresponding to the position corresponding to the predetermined image is provided with an image of the second image data at a position corresponding to the white image at a corresponding position of the third image data. In the position of the part Position providing an image adjusting at least the former of density and hue in accordance with the image, an image forming apparatus.

  According to a seventh aspect of the present invention, in the image forming apparatus according to the sixth aspect, the image forming unit includes the same number of unit images of yellow, magenta, and cyan in the predetermined image portions of the patterns. An image of the formed first image data is formed.

  According to an eighth aspect of the present invention, a plurality of patterns each composed of a plurality of unit images are continuously formed, and each of the patterns is an image in which some of the unit images are white images and other unit images are predetermined. The computer executes generation means for generating third image data based on the first image data of the image formed in step 2 and the second image data of the original document, and the generation means When the image of the first image data and the image of the second image data are superimposed, the image of the second image data at the position corresponding to the white image is set to the corresponding position of the third image data. A computer provided with an image in which at least the former of density and hue is adjusted according to the partial unit image at a position of the third image data corresponding to a position corresponding to the predetermined image; reading Ri can be image processing program.

  The invention according to claim 9 includes a translucent print medium and a decoded image formed on the print medium, and the decoded image includes a plurality of patterns each including a plurality of unit images. In each of the patterns, a part of the unit image can be seen through the printing medium, and the other side can be seen as a predetermined image, and a decoded image is formed. When the decoded image print medium is overlapped with the print medium in a predetermined positional relationship, an image at a position corresponding to the partial unit image of the original image is viewed from the position of the partial unit image. This is a decoded image print medium.

  A tenth aspect of the present invention includes a print medium and a decoded image formed on the print medium, and the decoded image includes a decoded image formed on the print medium, and the decoded image includes a plurality of units. A plurality of patterns each formed from an image are continuously formed, and each of the patterns has a part of the unit image that can be viewed through the print medium, and the other unit images are formed by a predetermined image. When the decoded decoded image print medium is overlapped with the print medium in a predetermined positional relationship, an image at a position corresponding to the partial unit image of the original image is determined from the position of the partial unit image. This is a decoded image print medium that can be seen.

  According to the first aspect of the present invention, the third image data whose contents of the original document cannot be read without superimposing the decoded document print medium based on the first image data on the original document of the monochrome image based on the second image data. The decrypted document print medium can be generated.

  According to the second aspect of the present invention, the third image data cannot be read out without superimposing the decoded document print medium based on the first image data on the original document of the color image based on the second image data. The decrypted document print medium can be generated.

  According to the third aspect of the present invention, it is possible to make it difficult to guess the content of the image of the decrypted document print medium based on the first image data, as compared with the case where this configuration is not provided.

  According to the fourth aspect of the present invention, the original document based on the second image data and the decrypted document print medium based on the first image data can be superimposed in any positional relationship as compared with the case where this configuration is not provided. Thus, it is difficult to guess whether the content of the decrypted document print medium can be decrypted.

  According to the fifth aspect of the present invention, it is possible to encrypt the contents of the original document based on the plurality of second image data in the decrypted document print medium based on the third image data.

  According to the sixth aspect of the present invention, the content of the original document cannot be read unless the decrypted document print medium based on the first image data is superimposed on the original document based on the second image data. A document print medium can be generated.

  According to the seventh aspect of the present invention, when the decrypted document print medium based on the third image data and the decrypted document print medium based on the first image data are overlapped as compared with the case where this configuration is not provided. Even if the image of the decrypted document print medium displayed in a part of the unit image of each pattern is white or black, it is possible to easily obtain contrast with surrounding images.

  According to the eighth aspect of the present invention, the content of the original document cannot be read unless the decrypted document print medium based on the first image data is superimposed on the original document based on the second image data. A document print medium can be generated.

  According to the ninth aspect of the present invention, it is possible to provide a decrypted document print medium that can read the contents of the original document by overlapping the decrypted document print medium.

  According to the tenth aspect of the present invention, it is possible to provide a decrypted document print medium in which the content of the original document can be read by being superimposed on the decrypted document print medium.

1 is an explanatory diagram showing a schematic configuration of an image forming system according to an embodiment of the present invention. 1 is a block diagram of electrical connection of an image forming apparatus according to an embodiment of the present invention. FIG. 6 is an explanatory diagram for explaining an overview of processing executed by the image forming apparatus according to the embodiment of the present invention. FIG. 6 is an explanatory diagram for explaining an overview of processing executed by the image forming apparatus according to the embodiment of the present invention. FIG. 6 is an explanatory diagram for explaining an overview of processing executed by the image forming apparatus according to the embodiment of the present invention. FIG. 6 is an explanatory diagram for explaining an overview of processing executed by the image forming apparatus according to the embodiment of the present invention. FIG. 3 is a functional block diagram of processing executed by the image forming apparatus based on a program according to an embodiment of the present invention. It is explanatory drawing explaining the filter data in the image forming apparatus which is one embodiment of this invention. It is explanatory drawing explaining the filter data in the image forming apparatus which is one embodiment of this invention. It is explanatory drawing explaining the filter data in the image forming apparatus which is one embodiment of this invention. It is explanatory drawing explaining the production | generation of the encryption document data in the image forming apparatus which is one embodiment of this invention. It is explanatory drawing explaining the production | generation of the encryption document data in the image forming apparatus which is one embodiment of this invention. It is explanatory drawing explaining the production | generation of the encryption document data in the image forming apparatus which is one embodiment of this invention. It is explanatory drawing explaining the production | generation of the encryption document data in the image forming apparatus which is one embodiment of this invention. It is explanatory drawing explaining the production | generation of the encryption document data in the image forming apparatus which is one embodiment of this invention. It is explanatory drawing explaining the production | generation of the encryption document data in the image forming apparatus which is one embodiment of this invention. FIG. 6 is an explanatory diagram illustrating an example of an original document image corresponding to a 2 × 2 pattern in the image forming apparatus according to the embodiment of the present invention. It is explanatory drawing which shows the example of the image of the encryption document data corresponding to the 2 * 2 pattern in the image forming apparatus which is one embodiment of this invention. FIG. 4 is an explanatory diagram of an image obtained by superimposing a decoded image print medium in which an image of filter data is formed on a decoded image print medium according to an embodiment of the present invention, with the top, bottom, left, and right edges aligned. FIG. 4 is an explanatory diagram of an image obtained by superimposing a decoded image print medium in which an image of filter data is formed on a decoded image print medium according to an embodiment of the present invention, with the top, bottom, left, and right edges aligned. 6 is an example of an image of encrypted document data in which 3 × 3 2 × 2 patterns are formed in the image forming apparatus according to the embodiment of the present invention. 6 is an example of an image of filter data in which 3 × 3 2 × 2 patterns are formed in the image forming apparatus according to the embodiment of the present invention. 5 is an example in which an image of encrypted document data and an image of filter data 2 are superimposed on each other in the image forming apparatus according to an embodiment of the present invention. 6 is an example of an image of encrypted document data in which 3 × 3 2 × 2 patterns are formed in the image forming apparatus according to the embodiment of the present invention. 6 is an example of an image of filter data in which 3 × 3 2 × 2 patterns are formed in the image forming apparatus according to the embodiment of the present invention. 6 is an example of an image of filter data in which 3 × 3 2 × 2 patterns are formed in the image forming apparatus according to the embodiment of the present invention. 4 is an example of a state in which encrypted document data and filter data are superimposed on each other in the image forming apparatus according to the embodiment of the present invention. 4 is an example of a state in which encrypted document data and filter data are superimposed on each other in the image forming apparatus according to the embodiment of the present invention. FIG. 6 is an explanatory diagram illustrating encryption when an original document is a white image in the image forming apparatus according to an embodiment of the present invention. It is explanatory drawing explaining the decoding in the image forming apparatus which is one embodiment of this invention. FIG. 6 is an explanatory diagram illustrating encryption when an original document is a magenta image in the image forming apparatus according to an embodiment of the present invention. It is explanatory drawing explaining the decoding in the image forming apparatus which is one embodiment of this invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is an explanatory diagram showing a schematic configuration of an image forming system according to an embodiment of the present invention.

  In this image forming system, an image forming apparatus 1 that forms an image on a sheet as a print medium and a personal computer (PC) 3 of a user of the image forming apparatus 1 are connected via a communication unit such as a LAN 2. .

  FIG. 2 is a block diagram of electrical connection of the image forming apparatus according to the embodiment of the present invention.

  The image forming apparatus 1 implements the image processing apparatus and the image forming apparatus according to the present invention, and stores a CPU 11 that performs various operations and controls each part in a centralized manner, a program 12 that is executed by the CPU 11, and various fixed data. A main controller 15 having a ROM 13 and a RAM 14 serving as a work area for the CPU 11 is provided.

  The main control device 15 includes an image reading device 21 that reads an image of a document, an image forming device 22 that performs processing for forming an image on a print medium such as paper, and transmission / reception of facsimile data via a public telephone network 23. Is connected to a facsimile control device 24 for As a result, the image forming apparatus 1 can perform various processes such as copying, printing, facsimile transmission / reception, and scanning. In addition to the electrophotographic system, the image creator 22 can employ various systems such as an inkjet system, a silver salt photographic system, a sublimation thermal transfer system, a melt thermal transfer system, and a direct thermal recording system.

  The main control device 15 has a touch panel and various operation buttons, accepts various operations from the user, displays various messages to the user, and stores magnetic data for storing various data. A storage device 32, a communication interface (I / F) 33 that communicates with the PC 3 via the network 2, and an image memory 34 that stores image data are connected.

  Although the program 12 may be stored in the ROM 13 from the beginning, the program 12 is transmitted to the image forming apparatus 1 via the network 5 in the form of a carrier wave, and the transmitted program 12 is transmitted to the magnetic storage device 32 or the like. You may make it set up. Alternatively, the program 12 is provided in a state of being stored in a storage medium such as a CD, DVD, or MO, and the storage medium is read by a reading device such as an optical disk device, and the read program 12 is set up in the magnetic storage device 32 or the like. You may make it do.

  3 to 6 are explanatory diagrams for explaining an overview of processing executed in the image forming apparatus 1.

  The image forming apparatus 1 uses the encrypted document that is the image data of the encrypted document obtained by encrypting the original document 41 from the image data (second image data) 61 (see FIG. 7) of the original document 41 (FIG. 3). Data (first image data) 63 (see FIG. 7) is generated, image formation based on the encrypted document data 63 is performed on a print medium such as paper, and the encrypted document 42 serving as a decrypted image print medium. (FIG. 4) is generated. In addition, the encrypted document data 63 is generated using filter data (first image data) 62 (see FIG. 7), and image formation based on the filter data 62 is made of a translucent material such as an OHP sheet. The filter document 43 (FIG. 5) which becomes a decoded image print medium is also generated on the printed print medium. By viewing the filter document 43 overlaid on the encrypted document 42 generated in this way, an image of the original document 41 that has been encrypted and cannot be read on the encrypted document 42 appears as shown in FIG. .

  FIG. 7 is a functional block diagram of processing executed by the image forming apparatus 1 based on the program 12.

  When the user instructs the application software 51 to execute printing of the original document 41 on the PC 3, the image data 61 of the original document 41 is transmitted from the PC 3. In addition, the user selects a desired one from a plurality of types of filter data 62 prepared in the image forming apparatus 1 by the filter selection unit 52. The selected filter data 62 is sent to the encrypted document data generation unit 54 by the filter generation unit 53. The encrypted document data generation unit 54 encrypts the document data based on the image data 61 of the original document 41 (used after being converted into bitmap data) and the filter data 62 received from the encrypted document data generation unit 54. 63 is generated. The printing unit 55 forms an image on a printing medium such as paper based on the encrypted document data 63 by the image creator 22, and also forms an image on a translucent printing medium such as an OHP sheet based on the filter data 62. Form.

  Next, processing executed by the image forming apparatus 1 based on the program 12 will be described in detail.

  8 to 10 are explanatory diagrams for explaining the filter data 62. FIG.

  As shown in FIGS. 8 and 9, the filter data 62 is formed by continuously forming a plurality of unit cell patterns 72 including a plurality of unit images 71. By forming a plurality of the patterns 72, an example of a plurality of patterns referred to in the present invention is realized. The pattern 72 in the example of FIG. 8 is formed by four 2 × 2 unit images 71. The number of unit images 71 in the pattern 72 and the shape of the pattern 72 can be variously selected. The example of FIG. 9 shows an image of the filter data 62 composed of four 2 × 2 patterns 72 (for convenience of explanation, the filter data 62 is composed of only four patterns 72. The filter data 62 is composed of a larger number of patterns 72). Each unit image 71 is composed of a single pixel or a plurality of pixels.

  Any one unit image 71 in each pattern 72 becomes a transmission part 73, and no image exists (white image). The other three unit images 71 are formed as predetermined images. In this example, three unit images 71 are given Y (yellow), M (magenta), and C (cyan) colors (represented as Y, M, and C, respectively). The three unit images 71 realize an example of a predetermined image according to the present invention. When the same number of unit images 71 of Y, M, and C are present in each pattern 72, the filter document 43 is superimposed on the encrypted document 42 by mixing colors of Y, M, and C. Even if the image of the encrypted document 42 seen from the transparent portion 73 is white (no image) or black, it looks like a gray color that can easily be contrasted with the image.

  In this example, there is no regularity in which unit image 71 of the four unit images 71 in each pattern 72 becomes the transmission part 73, and it is difficult for a third party to estimate the position of the transmission part 73 in each pattern 72. It is. The position of the transparent portion 73 in each pattern 72 may be determined by a random number, or an algorithm or a random number seed value may be used.

  Which of the plurality of types of filter data 62 is used is determined by displaying a filter selection screen as shown in FIG. 10 on the display on the PC 3 based on driver software that drives the image forming apparatus 1, and the plurality of filter data 62 (pattern 1, pattern 2...)).

  The filter data 62 to be used may be selected from those previously registered in the image forming apparatus 1, but the selected filter data 62 may be newly generated in the image forming apparatus 1.

Next, a procedure for generating the filter data 62 will be described. First, the size of the entire image of the filter data 62 is determined based on the document size of the original document 41. For example, in the case of an A4 document, the size of the entire filter image at 300 dpi is
210.0 × 297.0 (mm) = 2480 × 3508 (pixel)
It becomes.

Next, this 2480 × 3508 (pixel) is divided for each pattern 72. That is, when each unit image 71 corresponds to one pixel on a one-to-one basis,
2480 × 3508 (pixel) = 620 × 877 (pattern)
It becomes.

  Thereafter, according to the pattern information prepared in advance, the unit images 71 of the colors of the transmissive portions 73, Y, M, and C are arranged for the respective patterns 72. As the pattern information, for example, information that indicates in what order the positions of the unit images 71 of the colors of the transmission parts 73, Y, M, and C are spread in the image of the filter data 62 is prepared in advance. May be. Alternatively, the position of the unit image 71 of each color of the transmission unit 73, Y, M, and C may be determined with a random number according to a random number seed value. In any case, the same filter data 62 as the previously generated filter data 62 is generated by using the same pattern information and random number seed value as the filter data 62 that has been generated previously. Is possible.

  Next, generation of the encrypted document data 63 by the encrypted document data generation unit 54 will be described.

  FIGS. 11-16 is explanatory drawing explaining the production | generation of the encryption document data 63. FIG.

  When generating the encrypted document data 63, the image of the original document 41 and the pattern 72 of the filter data 62 and the image of the original document 41 when the image of the original document 41 and the filter data 62 are overlapped so that the top, bottom, left, and right edges coincide with each other. Judge the correspondence of.

  Here, it is assumed that the image of the original document 41 corresponding to a certain pattern 72 illustrated in FIG. 8 is the image of FIG. Also in the image of FIG. 11, unit images 71 corresponding to the pattern 72, the pattern 72, and reference numerals 71 to 73 of the transmission unit 73 are given. In this example, the image at the position corresponding to the transparent portion 73 of the original document 41 is black.

  12 and 13 show an image of the encrypted document data 63 generated from the image of the pattern 72 illustrated in FIG. 8 and the image of the original document 41 illustrated in FIG. Also in the images of FIGS. 12 and 13, unit images 71 corresponding to the pattern 72, the pattern 72, and reference numerals 71 to 73 of the transmission unit 73 are attached. As shown in the figure, in the encrypted document data 63, if the image of the original document 41 at the position of the transparent portion 73 is black, a black image is formed (FIG. 12). In addition, a black image is formed in any one of the three unit images 71 other than the transmission portion 73, and a white image is formed in the remaining two (FIG. 13).

  On the other hand, it is assumed that the image of the original document 41 corresponding to a certain pattern 72 illustrated in FIG. 8 is the image of FIG. Also in the image of FIG. 14, unit images 71 corresponding to the pattern 72, the pattern 72, and reference numerals 71 to 73 of the transmission unit 73 are given. In this example, the image at the position corresponding to the transparent portion 73 of the original document 41 is white.

  FIGS. 15 and 16 show images of the encrypted document data 63 generated from the image of the pattern 72 exemplified in FIG. 8 and the image of the original document 41 exemplified in FIG. Also in the images of FIGS. 15 and 16, unit images 71 corresponding to the pattern 72, patterns 72, and reference numerals 71 to 73 of the transmissive portion 73 are given. As shown in FIG. 15, in the encrypted document data 63, if the image of the original document 41 at the position of the transparent portion 73 is white, a white image is formed (FIG. 15). Further, in the three unit images 71 other than the transmissive portion 73, a black image is formed in any two, and a white image is formed in the remaining one (FIG. 16).

  11 to 13, the image of the original document 41 at the position of the transparent portion 73 is black, and in the examples of FIGS. 14 to 16, the image of the original document 41 at the position of the transparent portion 73 is white. The number of three unit images 71 other than the transmissive part 73 is white or black is different depending on the color. This is because the number of white unit images 71 and the number of black unit images 71 in one pattern 72 are the same for all patterns 72 regardless of whether the image of the original document 41 at the position of the transparent portion 73 is black or white. It is. By doing so, the encrypted document 42 looks black with a uniform density throughout the color mixture even if the image of the original document 41 at the position of the transparent portion 73 is black or white. Thus, in the encrypted document data 63, in each pattern 72, the density of the other three unit images 71 is adjusted according to whether the image of the original document 41 at the position of the transparent portion 73 is black or white. .

  FIG. 17 is an explanatory diagram showing an example of an image of the original document 41 corresponding to the 2 × 2 pattern 72. FIG. 18 is an explanatory diagram illustrating an example of an image of the encrypted document data 63 corresponding to the 2 × 2 pattern 72.

  17 and 18, the unit images 71 corresponding to the pattern 72, the pattern 72, and reference numerals 71 to 73 of the transmission part 73 are attached. Further, the actual images of the original document 41 and the encrypted document data 63 are larger than this, but here, for convenience of explanation, the image of the original document 41 will be described as an example. Using the method described with reference to FIGS. 11 to 16, based on the image data of the original document 41 illustrated in FIG. 17 and the filter data 62 configured by the 2 × 2 pattern 72 illustrated in FIG. 9. When the encrypted document data 63 is generated, the image of the encrypted document data 63 is as shown in FIG. This image appears as a black image with a uniform density throughout.

  The image of the filter data 62 of FIG. 9 is translucent to OHP paper on the decrypted image print medium in which the image of the encrypted document data 63 of FIG. 18 generated in this way is formed on a print medium such as paper. FIG. 19 shows an image obtained by overlapping the decoded image print medium formed on the print medium with the top, bottom, left and right ends aligned. When this is compared with the original document 41 in FIG. 17, the black image is reproduced in each of the four unit images 71 in the pattern 72 in which the black image is displayed among the 2 × 2 patterns 72. Yes. Moreover, in the pattern 72 in which the white image is displayed among the 2 × 2 patterns 72, the white image is reproduced by each one of the four unit images 71. In the other unit images 71, since the image of the filter data 62 is displayed, it looks gray. Therefore, an image obtained by superimposing the decoded image print medium on the decoded image print medium looks like FIG. An image obtained by superimposing the decoded image print medium on the decoded image print medium reproduces the original document 41 with a resolution of 1/4.

  The decoded image print medium generated as described above cannot be printed without the decoded image print medium. However, if a third party can obtain not only the decrypted image print medium but also the decrypted image print medium, the decrypted image print medium can be read. In this case, the decoded image print medium and the decoded image print medium are not overlapped with the top, bottom, left, and right edges aligned, but are overlapped with each other so as to have a predetermined positional relationship. If the decoded image print medium can be read, the decoded image print medium cannot be read even if the decoded image print medium can be obtained as well as the decoded image print medium unless the positional relationship is known. Below, the example which enables such a thing is demonstrated.

  In this example, it is assumed that the original document 41 and the filter data 62 are superposed while being shifted from each other by one unit image 71 in the left-right direction and one unit image 71 in the vertical direction. The encrypted document data 63 is created by the method described above.

  FIG. 21 shows an example of an image of encrypted document data 63 in which a 2 × 2 pattern 72 is formed in 3 × 3. FIG. 22 is an example of an image of the filter data 62 in which 2 × 2 patterns 72 are formed in 3 × 3. FIG. 23 shows an example in which the image of the encrypted document data 63 and the image of the filter data 62 are superimposed. Thus, the content of the encrypted document data 63 can be read by superimposing one unit image 71 in the left-right direction and one unit image 71 in the up-down direction while being shifted from each other.

  In this case, in the unit image 71 where the encrypted document data 63 and the filter data 62 do not overlap each other, a dummy image 81 having a density that does not cause a sense of incongruity with other portions is formed.

  In the above example, one original document 41 is encrypted on one decrypted image print medium, but a plurality of original documents 41 are encrypted on one decrypted image print medium. Is also possible.

  In this case, for example, different filter data 62 is prepared for each of the two original documents 41, and the positions of the transparent portions 73 in the patterns 72 are not overlapped with each other in the two filter data 62. The image of the original document 41 corresponding to the transparent portion 73 when the first filter data 62 is overlaid is left in the encrypted document data 63, and similarly, the 21st original document 41 and the second filter are left. The image of the original document 41 corresponding to the transparent part 73 when the data 62 is overlaid is also left in the encrypted document data 63.

  FIG. 24 is an example of an image of the encrypted document data 63 in which a 3 × 3 2 × 2 pattern 72 is formed. 25 and 26 are examples of images of filter data 62 in which 3 × 3 2 × 2 patterns 72 are formed. 27 and 28 show examples of the state in which the encrypted document data 63 and the filter data 62 are superimposed.

  FIG. 27 shows a state where the decrypted image print medium of the filter data 62 of FIG. 25 is superimposed on the decrypted image print medium of the encrypted document data 63 of FIG. FIG. 28 shows a state in which the decrypted image print medium of the filter data 62 of FIG. 26 is superimposed on the decrypted image print medium of the encrypted document data 63 of FIG.

  In the above example, the image of the original document 41 is an example of a white / black binary image. Next, processing when the original document 41 is a color image will be described.

  When the original document 41 is a color image (an image of any one of C, M, and Y), it is assumed that the image of the original document 41 and the image of the filter data 62 are overlapped. Are added to the image of the encrypted document data 63, and for the other three unit images 71, the density and hue are uniform for each pattern 72 as a whole in the image of the transmission unit 73 and the other three unit images 71. As such, the colors of the other three unit images 71 may be selected.

  FIG. 29 is an explanatory diagram for explaining encryption when the original document 41 is a white image, and FIG. 30 is an explanatory diagram for explaining decoding in this case.

  If the original document 41 is a white image as shown in FIG. 29, the white image of the unit image 71 of the original document 41 corresponding to the transparent unit 73 is put into the image of the encrypted document data 63. C, M, and Y images are randomly placed in the other three unit images 71 of the encrypted document data 63, and the other three unit images 71 so that the pattern 72 as a whole has a uniform density and hue. Are adjusted in accordance with the color of the unit image 71 of the original document 41 corresponding to the transmission unit 73.

  FIG. 30 shows a state where the encrypted document data 63 image and the filter data 62 image are overlaid and decrypted when the unit image 71 of the original document 41 corresponding to the transparent unit 73 is a white image. Show.

  FIG. 31 is an explanatory diagram for explaining encryption when the original document 41 is a Y image, and FIG. 32 is an explanatory diagram for explaining decoding in this case.

  When the original document 41 is a Y image as shown in FIG. 31, the Y image of the unit image 71 of the original document 41 corresponding to the transparent unit 73 is put in the image of the encrypted document data 63. White, C, and M images are randomly placed in the other three unit images 71 of the encrypted document data 63 so that the pattern 72 as a whole has a uniform density and hue. Are adjusted in accordance with the color of the unit image 71 of the original document 41 corresponding to the transmission unit 73.

  FIG. 32 shows a state where the image of the encrypted document data 63 and the image of the filter data 62 are superimposed and decrypted when the unit image 71 of the original document 41 corresponding to the transparent unit 73 is a Y image. Show.

  Similarly, in the case where the original document 41 is an M image, the M image of the unit image 71 of the original document 41 corresponding to the transparent unit 73 is put into the image of the encrypted document data 63. The other three unit images 71 of white, C, and Y are randomly placed in the other three unit images 71 of the encrypted document data 63 so that the pattern 72 as a whole has a uniform density and hue. Are adjusted in accordance with the color of the unit image 71 of the original document 41 corresponding to the transmission unit 73.

  When the original document 41 is a C image, the C image of the unit image 71 of the original document 41 corresponding to the transparent unit 73 is put into the image of the encrypted document data 63. White, M, and Y images are randomly placed in the other three unit images 71 of the encrypted document data 63, and the other three unit images 71 so that the entire pattern 72 has a uniform density and hue. Are adjusted in accordance with the color of the unit image 71 of the original document 41 corresponding to the transmission unit 73.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 12 Program 52 Filter selection means 53 Filter generation means 54 Encrypted document data generation means 55 Printing means

Claims (10)

A plurality of patterns each consisting of a plurality of unit images are continuously formed, and each of the patterns is a first of images in which some of the unit images are formed as white images and other unit images are formed as predetermined images. Generating means for generating third image data based on the second image data of the original document and the second image data of the original document,
The generating means converts the image of the second image data at the position corresponding to the white image when the image of the first image data and the image of the second image data are superimposed. An image whose density is adjusted according to the partial unit image is provided at the position of the third image data corresponding to the predetermined image.
Image processing device. A plurality of patterns each consisting of a plurality of unit images are continuously formed, and each of the patterns is a first of images in which some of the unit images are formed as white images and other unit images are formed as predetermined images. Generating means for generating third image data based on the second image data of the original document and the second image data of the original document,
The generating means converts the image of the second image data at the position corresponding to the white image when the image of the first image data and the image of the second image data are superimposed. An image whose density and hue are adjusted according to the partial unit image is provided at a position of the third image data corresponding to the predetermined image.
Image processing device.   The image processing apparatus according to claim 1, wherein the generation unit generates the third image data based on the first image data in which the position of the white image in each pattern is irregular. .   The generating means is configured to position the second image data at a position corresponding to the white image when the first image data image and the second image data image are shifted and overlapped with each other in a predetermined positional relationship. Is provided at a corresponding position of the third image data, and the position of the third image data at a position corresponding to the predetermined image has a density according to the partial unit image. The image processing apparatus according to claim 1, wherein an image with adjusted hue is provided.   The generating means is at a position corresponding to the white image when the image of the first image data and the image of the second image data are superimposed using a plurality of types of the second image data. The image of said 2nd image data is provided in the applicable position of said 3rd image data so that it may not overlap between said 2nd types of said 2nd image data. Image processing apparatus. A plurality of patterns each consisting of a plurality of unit images are continuously formed, and each of the patterns is a first of images in which some of the unit images are formed as white images and other unit images are formed as predetermined images. Generating means for generating third image data based on the second image data of the original document and the second image data of the original document;
Image forming means for forming an image on a print medium based on each of the first image data and the third image data;
With
The generating means converts the image of the second image data at the position corresponding to the white image when the image of the first image data and the image of the second image data are superimposed. The position of the third image data corresponding to the position corresponding to the predetermined image is adjusted at least the former among the density and hue according to the partial unit image. Provide the image
Image forming apparatus.   6. The image forming unit according to claim 5, wherein the image forming unit forms an image of the first image data in which the same number of unit images of yellow, magenta, and cyan are formed in the predetermined image portion of each pattern. Image forming apparatus. A plurality of patterns each consisting of a plurality of unit images are continuously formed, and each of the patterns is a first of images in which some of the unit images are formed as white images and other unit images are formed as predetermined images. Causing the computer to execute generation means for generating the third image data based on the image data of the first document and the second image data of the original document
The generating means converts the image of the second image data at the position corresponding to the white image when the image of the first image data and the image of the second image data are superimposed. The position of the third image data corresponding to the position corresponding to the predetermined image is adjusted at least the former among the density and hue according to the partial unit image. Provide the image
A computer-readable image processing program. A translucent print medium;
A decoded image formed on the print medium;
With
In the decoded image, a plurality of patterns each composed of a plurality of unit images are continuously formed, and each of the patterns can be viewed through the print medium so that a part of the unit image is the other side. Is formed of a predetermined image, and when the decoded image print medium on which the decoded image is formed is overlapped with the print medium in a predetermined positional relationship, the partial unit image of the original image The image of the position corresponding to can be seen from the position of the partial unit image,
Decoded image print medium. Print media;
A decoded image formed on the print medium;
With
In the decoded image, a decoded image is formed on a print medium, and the decoded image is continuously formed with a plurality of patterns each composed of a plurality of unit images, and each of the patterns is part of the unit image. The other unit image can be seen through the decoded image print medium formed with a predetermined image superimposed on the print medium in a predetermined positional relationship, and the original image An image at a position corresponding to a part of the unit image can be viewed from the position of the part of the unit image.
Decoded image print medium.

Images