JP5732693B2 - Method for producing halftone dot printed matter and recording medium storing software for producing halftone dot printed matter - Google Patents

Description

  The present invention provides a method for producing a halftone dot printed material and a software for producing the halftone dot printed material, which particularly require delicate halftone dot composition, in valuable printed matter that requires prevention of counterfeiting and tampering such as banknotes, passports, and securities. It relates to the stored recording medium.

  In recent years, counterfeit printed products such as banknotes, passports, and securities have become a serious problem due to high performance and high image quality of copiers. For this reason, functional inks that are difficult to reproduce color, gloss, light emission and the like with a copying machine have been conventionally used for precious printed matter. Functional inks include gold inks, silver inks, pearl inks, and other metallic glossy inks whose color and gloss are difficult to reproduce in copying machines, and infrared absorbing inks that exhibit absorption characteristics in the infrared region.

  When authenticating printed matter using infrared absorbing ink, an identification device such as an infrared camera is required. On the other hand, when authenticating printed matter using metallic gloss ink, it is only necessary to pay attention to changes in color and gloss, and it can be easily determined visually without using an appraisal device. For this reason, many valuable prints are used in combination with a plurality of functional inks having different ink characteristics.

  For example, in Patent Document 1 filed earlier by the present applicant, cyan (C), which is used in general commercial printing, in the case where two different images are equally arranged as a halftone dot image on the same plane, A halftone dot printed matter is disclosed in which a visible image and a latent image are generated using basic inks of magenta (M), yellow (Y), and black (K). Cyan (C), magenta (M) and yellow (Y) used in general commercial printing do not absorb infrared rays. Therefore, mixed color black in which cyan (C), magenta (M), and yellow (Y) are superposed does not absorb infrared rays. On the other hand, black (K) is mainly composed of carbon black and exhibits absorption over the entire region from the ultraviolet region to the infrared region.

  Using this characteristic, halftone prints printed based on a predetermined arrangement rule using cyan (C), magenta (M), yellow (Y), black (K), and mixed color black are visible under a visible light source. A latent image that can be observed using an identification device such as an infrared camera can be embedded in the visible image. The produced halftone printed matter does not require the use of special ink, and thus can be produced at low cost, and cannot be duplicated with the current photoengraving apparatus, and therefore has an excellent anti-counterfeit effect.

  FIG. 1A is an example of a diagram showing a halftone dot configuration of a printed material in Patent Document 1, and a plurality of first regions (1) and second regions (2) are arranged without overlapping each other. Yes. The first halftone dot portion (1a) was formed with basic inks of cyan (C), magenta (M) and yellow (Y). A plurality of first halftone dot portions (1a) become a first image which is a visible image. The second halftone dot portion (2a) is formed using a monochromatic black material containing an infrared absorbing pigment (for example, carbon black containing carbon), and the second background portion (2b) is an infrared ray. It was formed using a mixed color black in which cyan (C), magenta (M), and yellow (Y) without an absorbing dye were superimposed. A plurality of second halftone dots (2a) provide a second image that can be observed in an infrared environment.

  When the produced printed material is observed under a visible light source, a first image, which is a visible image formed of color materials of cyan (C), magenta (M), and yellow (Y), is visually recognized. When observed in an infrared environment, a second image that is a latent image formed of carbon black appears. When the produced printed matter is copied, the second halftone dot portion (2a) and the second background portion (2b) are not distinguished from each other, and a black-colored reproduction is formed. It becomes impossible to observe the latent image.

  The special halftone dot composition proposed in Patent Document 1 described above can be easily produced by the halftone dot printed material production method disclosed in Patent Document 2 filed by the present applicant. By the halftone dot printed matter manufacturing method of Patent Literature 2, it is possible to obtain a special halftone dot configuration disclosed in Patent Literature 1 as an output in a desired state.

  FIG. 2 is a flowchart showing a method for producing a halftone print in Patent Document 2. First, the first image. The first original image to be recognized as a visible image on the printed material is input to the image processing unit, and expressed by pixels having the size of monochromatic halftone dots, presence / absence, presence / absence of monochromatic pixels, or density / gradation information of monochromatic pixels A first image to be generated is generated (STEP 1).

  Next, a gray image having the same image width and image height as the first image is generated, and this gray image is input to the image processing unit (STEP 1 ′), converted by the mask image generating unit, and mask image Is obtained (STEP 2).

  Next, the second original image that is the basis of the second image is input to the image processing unit so as to have the same image width, image height, and image resolution as the first image, and the monochrome halftone dot A second image that is recognized under certain observation conditions is generated based on the size of the area or the density of the monochrome pixel distribution (STEP 1 ″).

  Next, the mask image and the second image are input to the mask processing unit, and mask processing is performed (STEP 3). This is because the second image is subjected to a process of replacing all portions corresponding to the white pixels of the mask image with white pixels, so that the portion corresponding to the first region (1) in the second image is changed. All are replaced with white.

  The mask image obtained in STEP 2 is superimposed on the first image input in STEP 1, and further, the second image after mask processing obtained in STEP 3 is superimposed thereon to synthesize all the images. (STEP4).

  The image data created through the above steps includes two pieces of image information: a first image created based on the first original image and a second image created based on the second original image. . A printed matter is produced based on the image data. Examples of the production of the printed material include a method in which image data is color-separated and a printing plate surface is output and printed by a commercial printing machine, and a method in which the image data is directly output by an ink jet printer.

  When the halftone dot printed matter produced by the above method is observed under predetermined observation conditions, the first image is visually recognized by the naked eye, and the second image made of carbon black is visually recognized by infrared observation.

  According to this method, when creating image data using halftone dots, there are restrictions on the size of two types of halftone dot areas, such as making the size of the second area (2) larger than the size of the first area (1). In addition, the size of the first region (1) and the size of the second region (2) may be the same, increasing the degree of freedom of image data production by halftone dots.

  It is possible to automatically create image data of an arbitrary condition in a printed matter having two types of halftone dot regions, thereby reducing the mixing of work mistakes by the creator and further shortening the work time. Furthermore, since the processing steps relating to mask generation are greatly reduced, the time required for producing image data is shortened.

  Moreover, even if the number of processing steps related to image data production is reduced, it is possible to print one image in a predetermined area, as in the past, but without overlapping two images in a predetermined area, and An image is arranged in a predetermined area equally without causing the fusion of halftone dots, and is used in four colors of cyan (C), magenta (M), yellow (Y) and black (K) which are widely used in the general market. It is possible to realize security printing at low cost.

  The halftone dot print disclosed in Patent Document 1 has two images: a visible image that can be recognized with visible light, and a latent image that can be visually recognized using an identification device such as an infrared camera, due to a special halftone dot configuration. It was possible to produce it inexpensively. However, since the latent image cannot be visually recognized unless an appraisal device such as an infrared camera is used, for example, inspectors in various window operations such as banks and immigration examinations cannot perform authenticity determination by visual inspection. There was a problem.

  Therefore, in various window operations, the applicant observes in the diffused light region under a visible light source as a forgery-preventing printed material to which a latent image that can be visually discriminated is added without using an appraisal device. The first image, which is a visible image, can be visually recognized, and the second image, which is the first latent image, can be visually confirmed by observing the printed material at an angle. Further, an appraisal device such as an infrared camera is used. Have been filed for a printed matter in which the third image, which is the second latent image, can be visually recognized. In other words, it is possible to form three images with different viewing conditions on a single printed matter, and it is possible to perform double confirmation of authenticity determination using a simple method and authenticity determination using an appraisal device. (Patent Document 3)

  FIG.1 (b) is an example of the figure which shows the halftone dot structure of the printed matter in patent document 3, and 1st area | region (1), 2nd area | region (2), and 3rd area | region (3) are two or more sets. Has been placed. In addition, the printed material is obtained by overlapping two images composed of halftone dots on the same plane proposed by the applicant in Patent Document 1 shown in FIG. It is generated by using a part of the image processing method arranged without any gaps.

  The first halftone dot portion (1a) was formed with basic inks of cyan (C), magenta (M) and yellow (Y). A plurality of first halftone dot portions (1a) become a first image which is a visible image. Moreover, the 2nd halftone dot part (2a) was formed using the material containing an infrared absorptive pigment | dye, and the 2nd background part (2b) was formed using the material which does not contain an infrared absorptive pigment | dye. A plurality of second halftone dots (2a) provide a second image that can be observed in an infrared environment.

  Further, the third halftone dot portion (3a) has a color difference ΔE from the third background portion (3b) by changing the observation angle from the diffuse light region to the regular reflection light region with respect to the illumination light source at a fixed position. The third background portion (3b) was formed using a material containing an infrared absorbing dye. A plurality of third halftone dots (3a) form a third image that can be observed by tilting a specularly reflected light region, for example, a substrate.

Japanese Patent No. 3544536 JP 2009-202420 A Japanese Patent Application No. 2009-072964

  In carrying out the manufacturing method disclosed in Patent Document 2, it is necessary to provide means for giving two types of halftone dots composed of two types of regions to one image. As such means, for example, Postscript halftone generation Halftone Type 16 exists.

  Postscript is a page description language published by Adobe Systems in 1984. Since it is possible to describe document information with a high degree of freedom by using this PostScript, PostScript is adopted in some laser printers, plate-making film output machines and the like in the printing field. In the present invention, the halftone dot generation method according to the Postscript language specification is called a Postscript halftone dot generation method.

  Halftone Type 16 is a kind of postscript halftone dot generation method described above. Normally, there is one type of halftone dot used in one printed matter, but HalftoneType 16 is characterized in that two types of halftone dots can be mixed in one printed matter. Therefore, it is possible to give two types of halftone dots composed of two types of regions to one image.

  However, since there is no general means for assigning three or more types of halftone dots to one image, the know-how of the creator is required to give such halftone dots. Therefore, with the production method disclosed in Patent Document 2, the printed material disclosed in Patent Document 1 can be produced, but the printed material disclosed in Patent Document 3 can be easily produced by a creator who does not have know-how. I can't.

  Moreover, in the production method of Patent Document 2, the halftone dot portions and the background portions arranged in each region of the printed matter disclosed in Patent Documents 1 and 3 are produced by tapping. Therefore, when the ejection timing of the ink jet is shifted, white spots may occur between the halftone dot portion and the background portion. Therefore, there is a demand for a method for easily producing the printed matter disclosed in Patent Literature 1 and Patent Literature 3 without causing white spots.

  The present invention aims to solve the above problems, and specifically, a printed material in which one image is composed of three or more types of regions and three or more types of halftone dots are given, To provide a method for producing a halftone print and a recording medium storing the software for producing the halftone dot print, in which even a creator who does not have know-how can easily produce a white dot between a halftone dot portion and a background portion. Objective.

  In order to achieve the above-mentioned object, the invention according to claim 1 is characterized in that a printing area is formed at least partially on the substrate, and the printing area includes a plurality of central areas, a plurality of first areas, and a plurality of second areas. ,..., A plurality of (N−1) th regions and a plurality of Nth regions (N is a natural number of 3 or more, the same shall apply hereinafter), and one region is surrounded by the first region. A central region is arranged, the central region is smaller in area than the first region, and is arranged along the outer periphery of the first region, and the second region,..., (N-1) And the Nth region are arranged in a central region adjacent to the first region and / or the first region, and the central region is a second region,..., (N−1) th. A first region, a second region, ..., an (N-1) th region and an Nth region, comprising at least one of a region and an Nth region. Are each composed of a halftone dot portion and a background portion, and are arranged in a plurality of first regions, a plurality of second regions,..., A plurality of (N−1) th regions and a plurality of Nth regions. The first image, the second image,..., The (N-1) th image and the Nth image are respectively formed by the plurality of halftone dot portions, and the first image The second image, ..., the (N-1) th image and the Nth image are embedded, and the first region, the second region, ..., the (N-1) th region and the Nth image The halftone dots in the region are different characteristics that are visible depending on the first observation condition, the second observation condition, the (N-1) th observation condition, or the Nth observation condition, which are all different observation conditions. The first image, the second image, ..., the (N-1) th image and the Nth image correspond to different properties of the material. A method for producing a halftone dot printed material having a latent image visible under observation conditions, wherein the first image, the second image, ..., the (N-1) th image and the Nth image base In each original image, at least three arbitrary common points are set as reference points in each original image, i) from each original image, a reference point corresponding to the reference point of each original image, An image generating step for generating each pixel image consisting of the pixels of the pixel, or ii) from each original image having a reference point corresponding to the reference point of each original image, and each pixel image and gray image consisting of a plurality of pixels When the image generation process to be generated and the image generation process are i), a plurality of first areas, a plurality of second areas,..., A plurality of (N−1) th areas, and a plurality of Nth areas. Using a format image consisting of a plurality of pixels in which the location of the area is set, Only the pixels at the arrangement locations of the plurality of second regions in the network image,..., Only the pixels at the plurality of (N-1) arrangement locations and only the pixels at the arrangement locations of the plurality of Nth regions. A mask image generation step for generating each mask image having a reference point corresponding to the reference point of each original image, in which a black pixel is used and a pixel at an arrangement position of another region is a white pixel, ), The minimum threshold value and / or the maximum threshold value corresponding to the brightness of the pixels constituting the gray image are set to a plurality of first regions, a plurality of second regions,. Using a format image composed of a plurality of pixels in which the arrangement locations of the region and the plurality of Nth regions are set, only the pixels at the arrangement locations of the plurality of second regions in the format image,. Only the pixel at the (N-1) th arrangement location and a plurality of Nth A mask image generation step for generating each mask image having a reference point corresponding to the reference point of each original image, in which only the pixels at the arrangement positions of the areas are black pixels and the pixels at the arrangement positions of the other areas are white pixels. And the reference point of each mask image and the second pixel image corresponding to each mask image,..., The reference point of the (N−1) th pixel image and the Nth pixel image, Of the two pixels, if the pixel constituting each mask image is a black pixel, the second pixel image,..., The pixels constituting the (N−1) th pixel image and the Nth pixel image are left, If the pixels constituting the pixels constituting the mask image are white pixels, the second pixel image,..., The (N-1) th pixel image and the pixels constituting the Nth pixel image are white pixels, It has a reference point corresponding to the reference point of the original image and consists of multiple halftone dots Second image,..., A mask processing step for generating the (N-1) -th image and the N-th image, and materials having different characteristics that can be visually recognized according to each observation condition, forming each halftone dot portion. And the color are set, and the black pixels in the first image, the second image,..., The (N−1) -th image and the N-th image are replaced with the colors that form the set halftone dot portions. A material having a different characteristic from a material having a different characteristic that can be visually recognized according to each observation condition for forming each background part, and each halftone part in the observation condition excluding each observation condition, etc. Each color is set, and the black pixel in each mask image is replaced with a color that forms each set background portion, and a first pixel image and a plurality of halftone dots generated in the mask processing step Second image, (N-1) th image and Nth image A method for producing a halftone dot printed material comprising: an image combining step of combining an image and each mask image by combining respective reference points to generate a combined image; and a step of applying the combined image to a substrate by a predetermined method It is characterized by being.

  The invention of claim 2 is the method for producing a halftone print according to claim 1, wherein the mask image generation step has the same shape and the same size as the first region when the image generation step is ii). , The second region,..., Among the pixels constituting the first region when at least part of the (N-1) th region and the Nth region are arranged in the first region. , The second region arranged in the first region,..., The brightness of the pixel forming the gray image is the highest in all pixels corresponding to the (N−1) th region and the Nth region. The first highest threshold setting step for setting the highest threshold that is higher in brightness than the high brightness, and the pixels that are assigned the highest threshold in the first highest threshold setting step among the pixels that constitute the first region are The lowest brightness of the pixels forming the gray image on different pixels The first threshold data generation step having a first minimum threshold value setting step for setting a minimum threshold value that is lower brightness, the second region having the same shape and the same size as the central region,. A second region arranged in the central region among the pixels constituting the central region when at least a part of the (N-1) region and the Nth region are arranged in the central region; A second threshold value is set for all pixels corresponding to the (N-1) th region and the Nth region, with a maximum threshold value that is higher than the highest brightness of the pixels forming the gray image. Among the pixels constituting the maximum threshold value setting step and the central region, the pixel different from the pixel assigned the highest threshold value in the second highest threshold value setting step has a lightness lower than the lowest lightness of the pixel forming the gray image, Lower brightness A second threshold data generation step having a second minimum threshold setting step for setting a low threshold, a command conversion step for converting the first threshold data and the second threshold data into a predetermined command, and conversion into a predetermined command The first threshold data, the second threshold data, and the gray image are combined and stored as halftone dot data, and the gray image that is part of the halftone dot data is configured for the stored halftone data. Among the pixels to be converted, all the pixels corresponding to the pixels set with the lowest threshold in the first threshold data and the second threshold data are converted into white pixels, and the highest threshold in the first threshold data and the second threshold data is Raster processing that converts all pixels corresponding to the set pixels to black pixels And a star processing step.

  The invention of claim 3 further includes a background image generation step between the mask processing step and the image synthesis step in the method for producing a halftone dot printed matter according to claim 1, wherein the background image generation step includes: The reference point in the mask image and the second image generated in the mask processing step corresponding to each mask image,..., The (N-1) th image and the reference point of the Nth image are combined, The reference point corresponding to the reference point of each original image is defined as a white pixel if the two pixels at the same position are both black pixels or both are white pixels, and a black pixel if only one is a black pixel. ,..., (N-2) background image and (N-1) background image, and each mask image in the image composition step after the background image generation step. Is replaced with each background image, then each halftone dot The material and color having different characteristics that can be visually recognized are set according to each observation condition, and black in the first image, the second image,..., The (N−1) th image and the Nth image. Replace the pixel with the color that forms each halftone dot part, form each background part, and a material that has different characteristics from the material that has different characteristics that are visible according to each viewing condition that forms each halftone dot part In each of the observation conditions except for each observation condition, a color that is the same color as each halftone dot is set, and the black pixels in each background image are replaced with the colors that form each set background, The second image generated in the mask processing step,..., The (N-1) -th image and the N-th image, and each background image are synthesized by matching their respective reference points to generate a synthesized image. And applying the composite image to the substrate by a predetermined method Oite is on the substrate, print each background portion, and characterized by applying the method for printing each dot portions on each background portion.

  Further, the invention of claim 4 is a recording medium storing a halftone print production software for executing the halftone print production method according to any one of claims 1 to 3 by a computer program. To do.

  When creating image data with halftone dots, the area and halftone dots that can be provided in one image data are not limited to two types, so one image consisting of three or more types of areas and three or more types of halftone dots can be created. It was possible to produce a halftone dot print.

  In addition, after generating a colored background image and creating image data using the background image, even if some of the images are shifted and synthesized, the background image Since it is exposed, it has become possible to produce a halftone dot printed material without white spots between the halftone dot portion and the background portion.

An example of the figure which shows the halftone dot structure of printed matter in patent document 1 and patent document 3. FIG. The flowchart which shows the preparation methods of the halftone dot printed matter in patent document 2. FIG. The flowchart which shows the preparation methods of the halftone dot printed matter concerning this invention. The schematic diagram which shows each reference point in the 1st pixel image and 2nd pixel image concerning this invention. The schematic diagram which shows the 1st original image and 1st pixel image which concern on this invention. The schematic diagram which shows the format image and 1st mask image concerning this invention. The schematic diagram which shows the mask process process which produces | generates the 2nd image concerning this invention. The schematic diagram which shows the background image production | generation process concerning this invention. The flowchart which shows the detail of STEP2 ^(N-1) concerning this invention. The figure which shows the 1st threshold data (16) in N = 3 concerning this invention. The schematic diagram which shows the threshold value setting of each pixel in the 1st threshold data production | generation means (9) concerning this invention. The block diagram which shows the apparatus (4) which produces the halftone dot printed matter concerning this invention. FIG. 9 is a schematic diagram showing a halftone dot configuration disclosed in Patent Document 3. The figure which shows the halftone dot structure concerning this invention. An example of the schematic diagram which shows the outline | summary of the computer system (18) concerning this invention. The figure which shows the 1st image (a), gray image (b), 2nd image (c), and 3rd image (d) in Example 1 and Example 2 concerning this invention. The figure which shows each mask image and the image after a mask process in Example 1 and Example 2 concerning this invention. The flowchart which shows the preparation methods of the halftone dot printed matter in Example 1 concerning this invention. FIG. 3 is a schematic diagram for synthesizing each image data in the first embodiment according to the present invention. The flowchart which shows the preparation methods of the halftone dot printed matter in Example 2 concerning this invention. The figure which shows each background image in Example 2 concerning this invention. The schematic diagram which synthesize | combines each image data in Example 2 concerning this invention.

  Embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiments to be described below, and various other embodiments can be implemented within the scope of the technical idea described in the claims.

  FIG. 1B is an example showing a halftone dot configuration of a halftone print in the present invention, and is the halftone dot configuration disclosed in Patent Document 3 filed by the applicant of the present invention. As shown in FIG.1 (b), the halftone dot printed matter in this invention is formed in the at least one part printing area | region on base materials, such as paper and a plastic card. The print area includes a plurality of center areas (c), a plurality of first areas (1), a plurality of second areas (2), and a plurality of third areas (3). Each area | region (1, 2, 3) is an area | region of the micro size which cannot distinguish and visually recognize each area | region with the naked eye.

  In the halftone dot configuration of the halftone print in the present invention, one central region (c) is arranged so as to be surrounded by the plurality of first regions (1). The center region (c) has an area smaller than that of the first region (1) and is arranged at equal intervals along the outer periphery of the first region (1). When the central region (c) is formed with an area larger than that of the first region (1), the third region (3) formed in the central region (c) under the first observation condition becomes noise. This is not preferable because the visibility of the image is reduced.

  The second region (2) and the third region (3) are arranged in the central region (c) adjacent to the first region (1) and / or the first region (1). The central region (c) includes at least one of the second region (2) and the third region (3). In addition, the arrangement | positioning location of the 1st area | region (1), 2nd area | region (2), and 3rd area | region (3) in a halftone dot structure is not limited to this, The detail about the aspect of this form Will be described later.

  The first region (1), the second region (2), and the third region (3) are each composed of a dot portion (1a, 2a, 3a) and a background portion (1b, 2b, 3b). The plurality of halftone dot portions (1a, 2a, 3a) arranged in the plurality of first regions (1), the plurality of second regions (2), and the plurality of third regions (3), respectively, One image, a second image, and a third image are formed. Note that the second image and the third image are embedded in the first image.

  Each halftone dot (1a, 2a, 3a) in each region (1, 2, 3) can be visually recognized by the first observation condition, the second observation condition, or the third observation condition, which are all different observation conditions. It is made of materials with different properties. In addition, each background portion (1a, 1b, 1c) in each region (1, 2, 3) is visible in each halftone dot portion (1a, 2a, 3a) in each region (1, 2, 3). In the observation conditions excluding the first observation condition, the second observation condition, and the third observation condition, the halftone dots (1a, 2a, 3a) in each region (1, 2, 3) are the same color respectively. And it forms with the material which has a different characteristic from the material which has a different characteristic which can be visually recognized by 1st observation conditions, 2nd observation conditions, and 3rd observation conditions.

  The first observation condition is an observation condition in which only the first halftone dot portion (1a) among the halftone dot portions (1a, 2a, 3a) in each region (1, 2, 3) is visible. . Note that the observation condition in which only the first halftone dot portion (1a) in the present invention is visible is that the halftone dot portion and the background portion in the other region are the same color, and the first halftone dot portion (1) in the first region (1) is the same color. Only the halftone dot portion (1a) and the first background portion (1b) are viewing conditions that are visually recognized as different colors.

  Similarly, the (N-1) viewing condition in which only the halftone dot portion, that is, only the Nth halftone dot portion is visible, is that the halftone dot portion and the background portion in other regions are the same color, This is a condition in which only the Nth halftone dot portion and the Nth background portion in the region can be visually recognized as different colors, and the description thereof will be omitted. Thereby, the first image, the second image, and the third image formed by the plurality of halftone dots (1a, 2a, 3a) correspond to different characteristics of the material forming the halftone dots. The latent image is visible under the observation conditions.

  The color matching in the present invention means that the color difference ΔE is less than 6. Generally, when the color difference ΔE is around 6, there is a possibility that the color difference ΔE is visually recognized as a different color. However, as described above, in the present invention, each region (1, 2, 3) is formed of a fine region that cannot be visually recognized by the naked eye. Therefore, as described above, if the color difference ΔE is less than 6, even with the naked eye, the halftone dot portion and the background portion are visually observed even in the (N−1) th observation condition in which only the Nth halftone dot portion is visible. The halftone dot portion and the background portion are visually recognized as the same color.

The color difference in the present invention is defined by ΔE in the CIE 1976 L ^* a ^* b ^* color system. The CIE 1976 L ^* a ^* b ^* color system is a color space recommended by the CIE (International Lighting Commission) in 1976, and is defined in JIS Z 8729 in the Japanese Industrial Standards. The color difference is a distance in a color space between two colors, and the color difference in the CIE 1976 L ^* a ^* b ^* color system is the difference between the L ^* difference, the a ^* difference, and the b ^* difference between the two colors. It can be obtained by adding each squared and taking the square root.

  The first region (1) is a region that forms a first image that is visible in a first observation condition, for example, a diffused light region under a visible light source. The first region (1) is composed of a first halftone dot portion (1a) and a first background portion (1b). A first image is formed by the plurality of first halftone dot portions (1a). The first image is given gradation according to the area ratio between the first halftone dot portion (1a) and the first background portion (1b) in the first region (1).

  The first halftone dot portion (1a) is made of a material having a property that can be visually recognized under the first observation condition, for example, a material that does not contain an infrared absorbing dye (for example, cyan (C), magenta ( M), yellow (Y)). The first halftone dot portion (1a) is formed of a material that does not contain an infrared absorbing dye, and is visible under the first observation conditions corresponding to the characteristics of the material that does not contain an infrared absorbing dye. When observed under the second observation condition and the third observation condition, the first image cannot be visually recognized.

  The second area (2) is an area for forming a second image that is visible under a second observation condition, for example, an infrared light source. The second region (2) is composed of a second halftone dot portion (2a) and a second background portion (2b). A second image is formed by the plurality of second halftone dots (2a). The second image is given gradation according to the area ratio between the second halftone dot portion (2a) and the second background portion (2b) in the second region (2).

  The second halftone dot portion (2a) is formed using a material having characteristics that can be visually recognized under the second observation condition, for example, a material containing an infrared absorbing dye (for example, carbon black).

  The second background portion (2b) is a color that is the same color as the second halftone dot portion (2a) under a visible light source and does not contain an infrared absorbing dye (for example, cyan (C), Formed using a mixed color of magenta (M) and yellow (Y). In the second observation condition corresponding to the characteristics of the material containing the infrared absorbing dye, the second halftone dot portion (2a) is visible and the second background portion (3b) cannot be visually recognized. Therefore, it becomes possible to visually recognize a second image composed of a plurality of second halftone dots (2a). In addition, when it observes on 1st observation conditions and 3rd observation conditions mentioned later, a 2nd halftone part (2a) and a 2nd background part (2b) are visually recognized as a same color. Thereby, the second halftone dot part (2a) and the second background part (2b) are the diffused light region under the visible light source which is the first observation condition and the third observation condition which will be described later. When the observation angle with respect to the illumination light source at the position is changed from the diffused light region to the regular reflected light region, it is visually recognized as the same color. That is, the second image cannot be visually recognized except for the second observation condition.

  The third region (3) is a region for forming a third image that can be viewed by tilting the substrate under a third observation condition, for example, a visible light source. The third region (3) is composed of a third halftone dot portion (3a) and a third background portion (3b). A third image is formed by the plurality of three halftone dots (3a). The third image is given gradation according to the area ratio between the third halftone dot portion (3a) and the third background portion (3b) in the third region (3).

  The third halftone dot portion (3a) is obtained by changing the observation angle from a diffused light region to a regular reflected light region with respect to a material having characteristics that can be visually recognized according to the third observation condition, for example, a fixed-position illumination light source. The material is formed using a material (for example, gold ink, silver ink, etc.) whose color difference ΔE with the third background portion (3b) changes by a predetermined value.

  The third background portion (3b) is formed using a material that is the same color as the third halftone dot portion (3a) in the diffused light region under the visible light source and contains an infrared absorbing dye. . By changing the observation angle with respect to the illumination light source at a fixed position from the diffused light region to the specularly reflected light region, the color difference ΔE with the third background portion (3b) corresponds to a material characteristic corresponding to a predetermined value change. Under the three observation conditions, the third halftone dot portion (3a) has a color difference with the third background portion (3b) and becomes visible, and the third halftone dot portion (3a) is configured by the third halftone dot portion (3a). An image can be visually recognized. When observed under the first observation condition and the second observation condition, the third halftone dot portion (3a) and the third background portion (3b) are under the visible light source that is the first observation condition. It is visually recognized as the same color under the diffused light region and the infrared light source that is the second observation condition. That is, the third image cannot be visually recognized except for the third viewing condition.

  In this way, each halftone dot (1a, 2a, 3a) in each region (1, 2, 3) has a first observation condition, a second observation condition, and a first observation condition that are all different observation conditions. It is made of a material having different characteristics that can be visually recognized according to three observation conditions. Thereby, the first halftone dot portion (1a) is observed under the observation conditions corresponding to the different characteristics of the material forming each halftone dot portion (1a, 2a, 3a), that is, under the first observation condition. The first image appears. In addition, under the second observation condition, the second halftone dot portion (2a) is observed, and the second image appears. Furthermore, under the third observation condition, the third halftone dot portion (3a) is observed, and the third image appears. Therefore, the halftone dot printed matter of the present invention has a plurality of latent image images under observation conditions corresponding to different characteristics of the material forming each halftone portion (1a, 1b, 1c) in each region (1, 2, 3). Visible.

  In FIG. 1B, the print areas are called a plurality of center areas (c), a plurality of first areas (1), a plurality of second areas (2), and a plurality of third areas (3). , Formed by a plurality of central regions (c) and three types of regions, but is not limited to three types, the first region (1), the second region (2), ... It can be formed by the (N-1) th region and the Nth region (N is a natural number of 3 or more).

  Further, the second image and the third image embedded in the first image are respectively composed of a plurality of second halftone dots (2a) and a plurality of third halftone dots (3a). Is formed. Therefore, as described above, the print area is divided into a plurality of center areas (c), a plurality of first areas (1), a plurality of second areas (2),. ) Region and a plurality of Nth regions (N is a natural number of 3 or more), the first region (1), the second region (2), ..., the (N-1) th region and the first region The halftone dots in the N region can be visually recognized according to the first observation condition, the second observation condition, ..., the (N-1) th observation condition or the Nth observation condition, which are all different observation conditions. Accordingly, the second image that can be visually recognized under the observation conditions corresponding to the different characteristics of the material in which each halftone dot portion is formed. (N-2) And the (N-1) th image can be embedded in the first image.

(Production method)
FIG. 3 is a flowchart showing a method for producing a halftone print in the present invention. With reference to a block diagram of an apparatus for producing a halftone dot printed material shown in FIG. The apparatus shown in FIG. 12 is an image processing apparatus (4) described in Japanese Patent Application Laid-Open No. 2009-202420 filed earlier by the present applicant.

  First, in the image generation step, the first image, the second image,..., The (N-1) th image and the original images that are the basis of the Nth image are acquired, and are common to the original images. Arbitrary at least three points of the position are set as reference points in each original image.

  The first original image, the second original image,..., The (N-1) th original image, and at least any three points at the same position in the Nth original image are respectively set in each original image. Set to the reference point. FIG. 4 is a schematic diagram showing reference points in the first original image shown in FIG. 4A and the second original image shown in FIG. 4B. The first original image is an original image serving as a basis of an image to be recognized in a first observation condition, for example, a diffused light region under a visible light source on a printed material. The second original image is an original image that is the basis of an image that is to be recognized on the printed material under a second observation condition, for example, an infrared light source.

  When setting the reference point, first, an arbitrary original image is selected from each original image. In FIG. 4, the first original image shown in FIG. 4A is selected, and then any three points are selected. In the first original image, first, after setting the first reference point (P1), a point at a distance of X1 from the first reference point (P1) in the X direction is set as the second reference point. A point (P2) was set, and a point at a distance Y1 from the first reference point (P1) in the Y direction was set as a third reference point (P3). Thus, P1, P2, and P3 were set as reference points in the first original image. Next, the reference point of the second original image shown in FIG. 4B is set at a position common to the three reference points set in the first original image.

  In the second original image, first, the first reference point (P1 ′) is set, and then X1 from the first reference point (P1 ′) in the X direction as in the first original image. The point at the distance is set as the second reference point (P2 ′). Further, a point at a distance of Y1 in the Y direction from the first reference point (P1 ') is defined as a third reference point (P3'). The distance between the three reference points in each original image is the same. In this way, any three points at common positions in the first original image and the second original image are set as the respective reference points.

  Similarly, in the third original image,..., The (N-1) th original image and the Nth original image, the three positions at the same positions as the first original image and the second original image Let the points be the respective reference points in the original image.

  When all the original images have the same size, it is possible to set a reference point at a common position in each original image by setting at least three of the four corners in each original image as reference points. It is. Further, general image formats such as the TIFF format, the JPEG format, and the BMP format have a characteristic that pixels are always arranged in parallel along two axial directions perpendicular to each other. Therefore, if each pixel image has the characteristic that all the pixels are always arranged in parallel along two orthogonal vertical and horizontal axis directions, the vertical and horizontal directions of each pixel image are self-explanatory and it is necessary to consider rotation Therefore, only one reference point is required for each pixel image.

Next, each pixel image having a reference point corresponding to the reference point of each original image and including a plurality of pixels is generated from each original image. (STEP1 to STEP1 ^(N) ).

  After each original image is input to the image input unit (6), the image processing unit (7) generates a first pixel image having a reference point corresponding to the reference point of each original image and including a plurality of pixels. (STEP 1).

  The plurality of pixels forming the first pixel image include pixels having the size of a single-color halftone dot, the density of a single-color pixel distribution, or gradation information. Monochromatic halftone dot area size means that multiple pixels of the same color are present in the first pixel image, and multiple pixels of the same color are arranged in either vertical or horizontal diagonal positions adjacent to each other to form halftone dots. Further, a plurality of halftone dots are formed in the first image, and the shade of the image that can be visually recognized is expressed by the size of the number of pixels constituting the halftone dots. The density of the distribution of monochromatic pixels means that a plurality of pixels of the same color exist in the first pixel image and do not form a halftone dot, and can be viewed by the average distance between the pixels of the same color. It represents the shade of the image. The pixel having gradation information is a pixel having the same color or a different color in the first pixel image, and represents the color and shading of the visible image by the set of pixels. .

  In the image processing unit (7), as a method for generating a first pixel image composed of a plurality of pixels, there is a method according to Halftone Type 16 of the postscript halftone dot generation method described above. It is possible to generate a first pixel image composed of a plurality of pixels by performing halftone processing on the first original image by a method according to Postscript halftone generation method HalftoneType16.

  The halftone process is a conversion process performed on an image having shading information. In the present invention, each original image input to the image input unit (6) is converted into halftone dots having an area corresponding to each gray level information at a predetermined interval specified in advance in each original image in the image processing unit (7). Such replacement processing is called halftone processing.

  FIG. 5A is a diagram showing a first original image, and FIG. 5B is a diagram showing a first pixel image. The first pixel image has a reference point corresponding to the reference point of the first original image. The first pixel image has a reference point (p1 ′) at the same position as the first reference point (P1) in the first original image, and further from the first reference point (p1 ′) in the X direction. In the same way as the first original image, the second reference point (p2 ′) is set to the distance X1, and further, the Y1 direction from the first reference point (p1 ′) is set to the distance Y1. It has a first reference point (p3 ′). The distance between any two pixels separated in the X direction or the Y direction in the first pixel image in the present invention is other than any two pixels existing on a straight line connecting the two pixels. A value obtained by adding 1 to the number of pixels.

  Thus, when the first pixel image and the second original image are images of the same size (X × Y) and any one of the four corners is set to a zero point, p1 ′ and p2 ′ in the first pixel image And p3 are the same distances as P1, P2, and P3 in the first original image, and P1 ′ and p1 ′, P2 and p2 ′, and P3 and p3 ′ are on the same position coordinates. This is referred to as having a reference point corresponding to the reference point of each original image in the present invention. Hereinafter, since the reference points corresponding to the reference points of each original image are the same, description thereof will be omitted.

  Similarly, from the second original image,..., The (N-1) th original image and the Nth original image, the second pixel image,..., The (N-1) th pixel image and the Nth image. A pixel image is generated. Each pixel image has a reference point corresponding to the reference point of each original image that is the basis of each pixel image.

Next, in the mask image generation step, the second image,..., The (second) are formed in the plurality of second regions,. Each mask image for arranging the N-1 image and the Nth image is generated (STEP2 to STEP2 ^(N-1) ).

  Each mask image is generated by using the format image shown in FIG. The format image refers to a plurality of first areas (1), second areas (2),..., (N-1) area and Nth area, which generate a halftone print in the present invention. It is an image in which how to arrange is set. As a format image generation method, first, how many latent images (second image,..., (N-1) th image and Nth image) to be embedded in the first image are embedded. Set. Next, the second area (2),..., The (N−1) th area and the Nth area, which are areas for forming the latent image, are divided into the first area (1) and the first area (1). A format image is generated by designing how to arrange in a central region adjacent to one region (1). The format image is composed of a plurality of pixels. In addition, the arrangement | positioning location of each area | region in a format image is produced | generated so that it may become the arrangement location of the halftone printed matter in Japanese Patent Application No. 2009-72964 for which it applied previously.

  After the format image generated in advance is input to the image input unit (6), each mask image is generated using the format image. First, a first mask image is generated (STEP 2). A 1st mask image is an image used when arrange | positioning a 2nd image to several 2nd area | region (2). In the format image, only the pixels at the arrangement locations of the plurality of second areas (2) are black pixels, and the pixels at the arrangement locations of the other areas are white pixels, so that the first mask shown in FIG. An image is generated. Each mask image has reference points (P1 ″, P2 ″, P3 ″) corresponding to the reference points of each original image.

  Similarly, the (N−1) th mask image is generated from the second mask image. Hereinafter, generation of the (N−1) th mask image will be described as a representative example.

Further, the (N-1) th mask image is generated using the format image input to the image input unit (6) (STEP2 ^(N-1) ). The (N-1) th mask image is an image used when arranging the Nth image in a plurality of Nth regions. In the format image, only the pixels at the arrangement positions of the plurality of Nth areas are set as black pixels, and the pixels at the arrangement positions of the other areas are set as white pixels, thereby generating the (N-1) th mask image.

Next, in the mask processing step, a reference point of each mask image, a second pixel image corresponding to each mask image,..., A reference point of the (N−1) th pixel image and the Nth pixel image, respectively. In addition, if the pixels constituting each mask image among the two pixels at the same position are black pixels, the second pixel image,..., The (N−1) th pixel image and the Nth pixel image are constructed. If the pixels constituting the mask image are white pixels, the second pixel image,..., The (N-1) th pixel image and the Nth pixel image are white pixels. , A second image composed of a plurality of halftone dots,..., An (N-1) th image and an Nth image are generated (STEP3 to STEP3 ^(N-1) ).

  By performing the mask processing step, the second pixel image has only the second halftone dot portion (2a) arranged in the plurality of second regions (2), ..., the (N-1) th pixel. The image includes only the (N-1) halftone dot portion arranged in the plurality of (N-1) regions and the Nth pixel image includes the Nth pixel arranged in the plurality of Nth regions. It is converted into an image consisting only of halftone dots. Thereby, a plurality of halftone dots forming each image can be allocated to the print area without being mixed. Therefore, any one of the first image, the second image,..., The (N−1) th image and the Nth image is visually recognized depending on the observation conditions corresponding to the characteristics of the material forming each halftone dot portion. Possible prints can be produced.

  FIG. 7 is a schematic diagram showing a mask processing step for generating a second image as an example. In FIG. 7, in order to describe in detail, each black pixel is indicated by oblique lines, and the black pixels in the first mask image shown in FIG. 7A are surrounded by thick lines. In the mask processing step, the reference point of the first mask image and the reference point of the second pixel image corresponding to the first mask image shown in FIG. 7A input to the mask processing unit (14) are matched. . The pixel image corresponding to the mask image is arranged in a plurality of second regions (2),..., (N−1) th region and Nth region which are black pixels in each mask image. Each pixel image generated from the second image,..., The (N-1) th image and each original image that is the basis of the Nth image is referred to as a corresponding pixel image. In the first mask image, the second pixel image generated from the second original image serving as the basis of the second image, which is arranged in the plurality of second regions (2) which are black pixels in the first mask image. Becomes a pixel image corresponding to the first mask image.

  Next, the reference points (P1 ″, P2 ″, P3 ″) of the first mask image shown in FIG. 7A and the reference points (P1 ′, P2 ′) of the second pixel image shown in FIG. P2 ′ and P3 ′). FIG. 7C is a schematic diagram when the first mask image and the second pixel image are combined. If the pixels constituting the first mask image among the two pixels at the same position when the two images are combined are black pixels (in bold lines), the pixels constituting the second pixel image are left. Further, if the pixel constituting the first mask image is a white pixel (outside the thick line), the second pixel image is set as a white pixel. By performing the mask process, the second image element does not correspond to the second region (2), that is, the first region (1), the third region (3),. The pixels forming the (N-1) region and the Nth region are white pixels. Accordingly, a second image including a plurality of second halftone portions (2a) shown in FIG. 7D is generated. Although not shown, the second image has a reference point corresponding to the reference point of the second original image (STEP 3). In order to explain in detail, in FIG. 7D, the black pixel portion of the first mask image is indicated by a bold line, but it does not actually exist.

  Similarly, mask processing is performed for each of the third image to the Nth image. Hereinafter, mask processing for the Nth pixel image will be described as a representative example.

Next, the (N-1) th mask image and the Nth pixel image are input to the mask processing unit (14), and the mask process is performed (STEP3 ^(N-1) ). ) Match the reference point of the mask image with the reference point of the Nth pixel image corresponding to the (N-1) th mask image. If the pixels constituting the (N-1) th mask image among the two pixels at the same position when the two images are combined are black pixels, the pixels constituting the Nth pixel image are left. Further, if the pixel constituting the (N-1) th mask image is a white pixel, the Nth pixel image is set as a white pixel. By performing the mask process, portions of the Nth image element that do not correspond to the Nth region, that is, the first region (1), the second region (2),. The pixels forming the area -1) are white pixels. Therefore, an Nth image including a plurality of Nth halftone dot portions is generated. The Nth image has a reference point corresponding to the reference point of the Nth original image.

  Finally, in the image composition unit (15), the first pixel image, the second image generated in the mask processing step,..., The (N−1) th image and the Nth image, and the first mask The image,..., The (N-2) th mask image and the (N-1) th mask image are synthesized by combining the respective reference points to generate a synthesized image (STEP 4).

  In the image composition step, first, the first pixel image, the second image after the mask processing step, and the first mask image are input to the image composition unit (15). Next, the first mask image is superimposed on the first pixel image by aligning the respective reference points, and the second image after the mask processing step is superimposed thereon by aligning the respective reference points, ..., and the (N-1) th mask image is superimposed on the respective reference points, and finally, the Nth image after the mask processing step is aligned with the respective reference points. Image data is completed by combining all the superimposed images and generating a combined image.

  In addition, before the process of superimposing the first mask image on the first pixel image and aligning the respective reference points, a process of replacing all black pixels of the first mask image with any single color pixel is included. (STEP 3 ″).

When the first mask image is overlaid on the first pixel image with the respective reference points aligned, the color of the first mask image remains as it is in the second background portion shown in FIG. 2b). The second background portion (2b) and the second halftone dot portion (2a) are substantially the same color except for the observation conditions corresponding to the characteristics of the material forming the second halftone dot portion (2a). Therefore, it is preferable to replace the second background portion (2b) with a monochrome pixel having an appropriate density. Similarly, each mask image may include a process of replacing all black pixels of each mask image with an arbitrary single color pixel (STEP 3 ^{(N−1) ′} ) before generating a composite image.

  The completed image data includes N pieces of image information including a first image, a second image,..., An Nth image. Based on the image data which is the data of the composite image, the composite image is applied to the substrate by a predetermined method (STEP 5). For example, the image data generated by the image processing device (4) is transferred and input to a desired plate making device such as an offset plate making device or a screen plate making device, so that cyan (C), magenta (M), yellow (Y) A printing plate such as black (K) is output. Next, by using the output printing plate surface and the material forming the halftone dot portion and the background portion in each region, printing is performed on the base material by a desired printing method suitable for the printing plate surface. It becomes. Alternatively, the image data generated by the image processing device (4) is transferred and input to an ink jet printer, and printing is performed on the base material using a material that forms a halftone dot portion and a background portion in each region. Then, a halftone print is prepared (STEP 5).

In addition, after the mask processing step, the first pixel image, the second image after the mask processing,..., The (N−1) th image and the Nth image are combined with each mask image, and combined. Although the method of completing image data by generating an image has been described, as another aspect, a background image generation step (STEP3 ^{′ to} STEP3 ^{(N−1) ′} ) between the mask processing step and the image synthesis step, and May further be included.

  In the first background image, black pixels are assigned to the pixels constituting the second background portion (2b), and white pixels are assigned to the pixels other than the pixels constituting the second background portion (2b). It is an image.

  By generating the first background image, the background of the plurality of second halftone dots (2a) forming the second image is left on the background of the first image and at the same time the second background. It is possible to perform processing that does not leave the gradation information of the first image on the background of the portion (2b). Thereby, in the image composition step, even when a plurality of halftone dots forming the image are shifted and combined when generating the combined image, the shifted portion is colored as the first background image. Therefore, the printed material produced based on the composite image data can be completed as a halftone dot printed material without white spots.

  The background image generation process includes a reference point in each mask image generated in the mask image generation process, a second image generated in the mask processing process corresponding to each mask image, (N-1) th. By combining the image and the Nth image, the two pixels at the same position are either black pixels or white pixels if they are both white pixels, and if either one is a black pixel, they are black pixels. , First background image,..., (N-2) background image and (N-1) background image are generated. Each background image also has a reference point at a common position with the reference point set for each pixel image described above.

  FIG. 8 is a schematic diagram illustrating a background image generation process for generating a first background image as an example. In the background image generation step, after input to the background image generation unit (5) in the image processing device (4), the reference points (P1 ″, P2 ″, P3 ″) and the reference points (P1 ′ ″, P2 ′ ″, P3 ′ ″) of the second image after mask processing shown in FIG. 8B, corresponding to the first mask image Adjust each. Next, if the two pixels at the same position are both black pixels or both are white pixels, the pixel is a white pixel, and if only one is a black pixel, the pixel is a black pixel, as shown in FIG. A first background image is generated. The first background image also has reference points (P1 "", P2 "", P3 ") corresponding to the reference points of the second original image.

  Similarly, each background image is generated from the second mask image to the (N-1) th mask image using the Nth image from the third image after the mask processing.

  When the reference point in the first mask image and the reference point in the second image are matched and matched, the two pixels at the same position are either black pixels or white pixels if both are white pixels. If only one of the pixels is a black pixel, the first background image can be easily generated by synthesizing the first mask image and the second image by, for example, XOR operation. There is a way to do it.

  The XOR operation is one of logical operations, and an operation method that outputs 1 (black pixel) only when the values of the input 1 (black pixel) and 0 (white pixel) combinations do not match. That is.

  For example, when two images, a first mask image and a second image subjected to mask processing, are combined by an XOR operation, the colors of the corresponding two dots are compared, and both are black pixels or two If both are white pixels, they are replaced with white pixels, and if only one of them is a black pixel, it is combined with a black pixel to generate a first background image. Thus, by using the XOR operation, it is possible to generate a desired background image for one operation. In order to perform the XOR operation, it is necessary to use an image processing device (4) that can replace white pixels and black pixels by rewriting color information of specific pixels.

  In the image composition step after the background image generation step, each image to be combined is different from the above-described aspect, and will be described below. First, in the image composition step, each mask image used in the above-described aspect is replaced with each background image generated in the background image generation step. Next, the first pixel image, the second image generated in the mask processing step,..., The (N−1) -th image and the N-th image, and each background image are combined to form a combined image. Generate (STEP 4).

  In the image composition step, first, the first pixel image, the second image generated in the mask processing step, and the first background image are input to the image composition unit (15). Next, the first background image is superimposed on the first image with the respective reference points aligned, and the second image generated in the mask processing step is superimposed on the first image with the respective reference points aligned. In addition, the (N-1) -th background image is superimposed on each reference point and the N-th image generated in the mask processing step is added to each reference point. The image data is completed by compositing all the images together and generating a composite image. The completed image data includes N pieces of image information including the first image, the second image,..., The Nth image, and each background image information.

  The completed image data includes the first image, the second image,..., N pieces of image information including the (N−1) th image and the Nth image, Contains image information. In the step of applying the composite image to the base material by a predetermined method based on the image data that is the composite image data, after printing each background image on the base material, The first image, the second image,..., The (N−1) th image and the Nth image made up of halftone dots are printed. As a result, even when the plurality of halftone dots forming each image are printed out of alignment with the base material, the base material is exposed because the shifted portions are colored as each background image. Thus, it is possible to produce a halftone dot printed product without causing white spots.

  Further, the method of generating each mask image by the mask image generation process using each pixel image generated in the image generation process has been described, but as another aspect, after further generating a gray image in the image generation process, In the mask image generation process, it is also possible to generate a mask image using a gray image.

  A gray image is an image that does not contain white and black pixels at all. When each mask image is generated without using a gray image as described above, only the pixels at the arrangement positions of the respective regions in the format image are generated as black pixels or white pixels one by one. Therefore, in order to determine whether or not each pixel is a pixel at an arrangement location and set a pixel, the know-how of the creator is required. On the other hand, when each mask image is generated using a gray image, since each mask image is generated using the above-described Postscript halftone generation method HalftoneType 16, general software capable of processing PostScript is used. Can be used. Therefore, most of the processing necessary for mask image generation can be processed by general software. Therefore, since the manufacturer's know-how is not required, each mask image can be easily obtained as compared with a method not using a gray image.

  For the gray image, the gray original image that is the basis of the gray image is input to the image input unit (6). Next, a pixel image having the largest size (X × Y) is selected from each pixel image, and the pixel image is the same size or larger than the pixel image, and is converted into an image formed by a plurality of pixels. As a result, a gray image is generated. By making it the same size as the largest pixel image, it becomes possible to cover the entire surface of each pixel image without deficiency in the mask image generation process, and in the mask processing process and the image composition process, the entire image is covered. Can be processed without hesitation. When all the pixel images have the same size, the gray image has the same size as each pixel image. As a result, the entire surface of the pixel image can be covered without excess or deficiency. The generated gray image also has a reference point corresponding to the reference point of each original image.

  The mask image generation process after the gray image generation process is different from the above-described aspect, and will be described below. First, in the mask image generation step, a reference point is set at a position common to each pixel image in the above-described format image. When setting the reference point, it is the same as each pixel image described above. Next, in the two pixels at the same position by combining the reference point of the gray image and the reference point of the format image, the highest threshold value and / or the lowest threshold value corresponding to the brightness of the pixels constituting the gray image are set to the format. It sets for every pixel which comprises the some 2nd area | region (2) in an image. The plurality of second regions (2) after the threshold setting is a first mask image (STEP 2). The first mask image has a reference point at a position in common with the reference point set in the second pixel image, as in the above-described aspect. When setting the reference point in the first mask image, it is set in the same manner as each pixel image described above.

  Similarly, in the mask image generation process after the gray image generation process, the (N-1) th mask image is generated from the second mask image.

  Next, a detailed process for generating each mask image from the gray image will be described using the (N-1) th mask image as an example.

FIG. 9 is a flowchart showing details of the step (N-1) th (N-1) mask image generation process in STEP 2 ^(N-1) in the overall flow showing the method for producing a halftone print in the present invention shown in FIG. The features of the present invention, which are different from the prior art, are shown.

According to the flowchart, first, a first threshold data generation step is provided (STEP2 ^(N-1) -1), and second, a second threshold data generation step is provided (STEP2 ^(N-1) - 2) Third, the first threshold data (16) obtained in the first threshold data generation step and the second threshold data (17) obtained in the second threshold data generation step are Provided is a command conversion process for converting the command into a command conforming to Halftone Type 16 (STEP2 ^(N-1) -3). Fourth, the first threshold data (16) converted into a predetermined command by the command conversion process and the second threshold A halftone data storage step for combining data (17) and storing the data as halftone data is provided ( ^{TEP2 (N-1) -4)} , Fifth, with respect to saved halftone data, raster processing means (13) provided to convert all of the pixels included in the first region (1) to a black pixel ( STEP2 ^(N-1) -5), and sixth, a black and white binary mask image is generated (STEP2 ^(N-1) -6).

(Embodiment of N = 3 in the Present Invention)
Next, as an example, the processing content in each step relating to the production of each mask image is N = 3, and the third region (3) shown in FIG. 1B is changed to the first region (1). The processing content in each step relating to the production of the second mask image regarding the case where it is included will be described in more detail. The size of each region shown in FIG. 1B is such that the outer shape of the first region (1) is j _x × j _y pixels, and the outer size of the second region (2) is k _x × k _y. and pixels, the contour of the third region (3) and _{m x} × _{m y} pixels. The following description will be made in accordance with the flowchart of FIG. 9 with reference to a block diagram of an apparatus for producing a halftone dot printed material shown in FIG.

First, first threshold data generation means (9) generates first threshold data (16) (STEP2 ⁽¹⁾ -1).

  FIG. 10A shows a plurality of first regions (1), a plurality of second regions (2),... ) And first threshold data (16) generated based on a plurality of Nth regions. The first threshold data (16) is an image necessary for designating a halftone dot shape within the outer shape of the first region (1) indicated by a broken line in FIG. In this step, the first threshold data (16) is used to designate the mask shape of the first mask image.

The first threshold data (16) has the same shape and the same size as the first area (1) in the format image. In FIG.6 (b), the 3rd area | region (3) is arrange | positioned in the 1st area | region (1). Since its among the first threshold data (16) shown in FIG. 10 (a), sets a sufficiently high brightness in all pixels corresponding to the third region (3) of m _x × m _y pixels The pixel is generated in a state where a sufficiently low brightness is set for all pixels not corresponding to the third region (3). The generated data is output to a recording medium in an appropriate image format such as bitmap data, and becomes first threshold data (16) as shown in FIG. The recording medium in the present invention is a flexible disk, a CD-R, a USB memory, a computer hard disk, or the like. A volatile memory such as a RAM is also used as a recording medium in the present invention.

  The sufficiently high brightness in the present invention refers to a brightness higher than the highest brightness included in the gray image. In the image format used in the first threshold data (16), a threshold value assigned to each pixel in order to express sufficiently high brightness is referred to as a first highest threshold value in the present invention.

  In order to avoid the influence of light and darkness of the gray image, it is desirable that the first highest threshold value and the second highest threshold value, which will be described later, have the highest brightness that can be expressed in the image format used when generating the respective threshold data. Note that, as described above, when the brightness is higher than the highest brightness included in the gray image, the brightness is not limited to the highest brightness that can be expressed in the image format used when generating each threshold data.

  When the gray image and / or image format of each threshold is a format that does not have lightness information directly and records RGB lightness or CMYK shading, it converts appropriately based on the value of each color component To get lightness. As such conversion, for example, there is an NTSC system used in Japanese television, and according to this system, brightness (luminance) Y uses RGB components, and Y = 0.299 × R + 0.587 ×. It is obtained by a conversion equation of G + 0.114 × B. Although description is omitted in the present invention, such conversion is appropriately performed as necessary in all processing relating to brightness.

  The sufficiently low brightness in the present invention refers to a brightness that is lower than the lowest brightness included in the gray image. In the image format used in the first threshold data (16), a threshold value assigned to each pixel in order to express sufficiently low brightness is referred to as a first minimum threshold value in the present invention.

  In order to avoid the influence of light and darkness of the gray image, it is desirable that the first minimum threshold and the second minimum threshold described later are the lowest brightness that can be expressed in the image format used when generating the respective threshold data. . Note that, as described above, when the brightness is lower than the lowest brightness included in the gray image, the brightness is not limited to the lowest brightness that can be expressed in the image format used when generating each threshold data.

For example, 0% concentration of white, when the 100% concentration and black, if a gray image input concentration of 50% solid image, among the first threshold data (16), a third m _x × m _y pixels By setting the brightness to be set for all the pixels corresponding to the region (3) to a density of 0 to 49%, the brightness is sufficiently high. Note that a gray image can be obtained by setting the highest brightness = density 0% that can be expressed in the image format used when generating the first threshold data (16) as the brightness of the first threshold data (16). Therefore, it is not necessary to reset each maximum threshold value regardless of the brightness, and this is preferable.

Similarly, if the gray image density of 50% of a solid image to be input, of the first threshold data (16), the brightness to be set to all pixels not corresponding to the third region (3) of m _x × m _y pixels Is set to a density of 51 to 100%, the lowest brightness is obtained. Note that by setting the lowest lightness = density 100% that can be expressed in the image format used when generating the first threshold data (16) as the lightness of the first threshold data (16), a gray image is obtained. No matter what brightness comes, it is not necessary to reset each minimum threshold value, which is preferable.

FIG. 11 is a detailed schematic diagram showing threshold setting of each pixel in the first threshold data generating means (9). FIG. 11A shows the state of the first threshold data (16) of j _x × j _y pixels shown in FIG. 10B before setting the threshold value of each pixel. The first threshold data (16), indicated by hatching, are included third region (3) of the m _x × m _y pixels before the threshold setting for each pixel. The threshold setting for each pixel is performed pixel by pixel as indicated by the arrows. In FIG. 11A, the threshold value is set for each pixel in the X direction (right direction in FIG. 11A). However, the present invention is not limited to this, and all threshold values in the first threshold data (16) are set. If a threshold value is set for a pixel, for example, it is possible to set the threshold value for each pixel in the Y direction (downward direction in FIG. 11A).

As shown in FIG. 11 (b), among the first threshold data (16), the pixel corresponding to the third region (3) of m _x × m _y pixels, it sets the first highest threshold. Further, as shown in FIG. 11 (c), of the first threshold data (16), the pixels not corresponding to the third region (3) of m _x × m _y pixels, sets the first minimum threshold . In the same procedure, as shown in FIG. 11 (d), threshold values are set for all the pixels of the first threshold data (16). By setting threshold values for all the pixels, first threshold data (16) in which the threshold values of each pixel are set as shown in FIG. 11E is generated.

  As described above, the first threshold data generating means in the case where N = 3 and the third area (3) is included in the first area (1) as shown in FIG. (9) is described. Therefore, when the third region (3) is not included in the first region (1) but is included in the second region (2), the threshold setting for each pixel shown in FIG. The second threshold data generating means (10) is used instead of the one threshold data generating means (9).

  In the case where the third region (3) is formed across both the first region (1) and the second region (2) as shown in FIG. The threshold value setting for each pixel shown in FIG. 11 is performed by both the first threshold data generating means (9) and the second threshold data generating means (10) described later.

Next, secondly, the second threshold data generating means (10) shown in FIG. 12 generates the second threshold data (17) (STEP2 ⁽¹⁾ -2).

  FIG. 10A shows a plurality of first regions (1), a plurality of second regions (2),... ) And second threshold data (17) generated based on a plurality of Nth regions. The second threshold data (17) is an image necessary for designating the halftone dot shape in the outer shape of the central region (c) indicated by the solid line in FIG. In this step, the second threshold data (17) is used to designate the mask shape of the second mask image.

  The second threshold data (17) has the same shape and the same size as the central area in the format image. In FIG. 6B, only the second region (2) is arranged in the central region (c). Therefore, the second threshold data (17) shown in FIG. 10A is generated with a sufficiently low brightness set for all pixels. In addition, when another area | region is arrange | positioned in center area | region (c), center area | region (c) among 2nd threshold data (17) similarly to 1st threshold data (16) mentioned above. A sufficiently high brightness is set for all the pixels corresponding to the area arranged inside.

  In the image format used in the second threshold data (17), a threshold value assigned to each pixel in order to express a sufficiently high brightness is referred to as a second highest threshold value in the present invention, and in order to express a sufficiently low brightness. In the present invention, the threshold value assigned to each pixel is referred to as a second minimum threshold value. A threshold is set for all the pixels of the second threshold data (17). By setting a threshold value for all the pixels, second threshold data (17) in which the threshold value of each pixel is set is generated.

Third, in the command conversion means (11) shown in FIG. 12, it is obtained by the first threshold data (16) and the second threshold data generation means (10) obtained by the first threshold data generation means (9). After the second threshold data (17) is converted into an appropriate image format such as a bitmap or RAW format, it is further converted into a command conforming to Halftone Type 16 of the Postscript halftone generation method (STEP2 ⁽¹⁾ -3 ^). ).

Fourth, the halftone data storage unit (12) shown in FIG. 12 combines and stores the output results of the command conversion unit (11) (STEP2 ⁽¹⁾ -4). In this output result, the command conversion means (11) uses the first threshold data (16) and the second threshold data (17), and HalftoneType16 of the Postscript halftone generation method for adding halftone dots to the gray image. The command according to is given.

  As described above, the threshold value of each pixel in the first threshold data (16) and the second threshold data (17) is the highest threshold value (a lightness value higher than the highest lightness value included in the gray image) and / or the lowest threshold value ( (Brightness lower than the lowest lightness included in the gray image) is set. In other words, all pixels that make up a gray image have a lightness that is higher than the minimum threshold value and lower than the maximum threshold value. Does not affect the results at all.

  For this reason, it is not necessary to take time and effort to generate a gray image, and the gray image is preferably a simple image, for example, a single color image using only a halftone gray having a density of 50%.

Fifth, the raster processing means (13) shown in FIG. 12 gives an instruction to the halftone dot generation device or software RIP, and converts the gray image using the output result of the halftone data storage means (12). A halftone dot is generated (STEP2 ⁽¹⁾ -5).

  A halftone dot generation device is a device that performs conversion for each position of an image having shading information and converts it into a halftone dot having an area corresponding to the shading information and outputs the converted image.

  Software RIP is software that converts an image composed of vector information such as a continuous line or continuous curve into an image composed of pixels and outputs the image. In general software RIP, a continuous line or continuous curve is output. When converting an image composed of vector information such as the above into an image composed of pixels, it has a function of replacing density information with halftone dots as in the halftone dot generator.

  Of the first threshold data (16) and the second threshold data (17), sufficiently low brightness is set for all pixels not corresponding to the third region (3). Therefore, in the raster processing means (13), all the pixels not included in the third region (3) in the gray image are converted into white pixels. Similarly, since all the pixels corresponding to the third region (3) in the first threshold data (16) and the second threshold data (17) have sufficiently high brightness, the gray image All the pixels included in the third region (3) are converted into black pixels.

Through the series of processes described above, a second mask image is generated in which black pixels are assigned to the third area (3) and white pixels are assigned to areas other than the third area (3) (STEP2 ^{( 1)} -6). By using this second mask image, it is possible to provide an independent third region (3) in one printed matter, and a third image which is an arbitrary image corresponding to the third region (3). It becomes possible to assign images.

Further, the ^STEP2 (1) instead -1~STEP2 of ⁽¹⁾ a third region in the processing of -6 (3), by performing the same processing with the second region (2) (STEP2- 1 to STEP 2-6), a first mask image is generated. By using this first mask image, it becomes possible to provide an independent second region (2) in one printed matter, and a second image which is an arbitrary image corresponding to the second region (2). It becomes possible to assign images. The generation of the first mask image and the provision of the independent second region (2) in one printed matter are described in detail in Japanese Patent Application Laid-Open No. 2009-202420 filed earlier by the present applicant. Has been.

  As described above, by generating each mask image, the first threshold data (16) is made to correspond to the first area (1), and the second threshold data (17) is all made to the second area (2). We were released from the conventional restriction that we had to deal with it. As a result, it is possible to secure N types or more, for example, three types of regions, and assign different images to the respective regions.

  As shown in FIG. 1B, the third region (3) may be arranged in the first region (1), but is not limited thereto. For example, in Patent Document 3, It is possible to adopt various halftone dot configurations disclosed. FIG. 13A is a schematic diagram showing each dot configuration disclosed in Patent Document 3, and for example, the third region (3) is changed into the first region (1) and the central region (c). You may form over the arrange | positioned 2nd area | region (2).

  As described above, the first threshold data (16) has the same shape and the same size as the first region (1), and the second threshold data (17) has the same size as the central region (c). . Therefore, the first threshold data (16) in the halftone dot configuration shown in FIG. 13 (a) is the third threshold data formed in the first region (1) as shown in FIG. 13 (c). It is generated by setting a sufficiently high brightness to the pixels corresponding to a part (3 ′) of the region (3). Similarly, as shown in FIG. 13D, the second threshold data (17) corresponds to a part (3 ′) of the third region (3) formed in the second region (2). It is generated by setting a sufficiently high brightness for the pixel to be processed.

  As shown in FIG. 14, the halftone dot printed material according to the present invention includes a first region (1), a second region (2), a third region (3), and an Nth region. You may be comprised by the pixel with the gradation information expressed by light / dark or color. In FIG. 14, only the first region (1) is configured by pixels having gradation information expressed by light and dark or color, but gradation information expressed by light and dark or color is used for a plurality of regions. It is good also as a pixel with.

  As for the production method further including the background image generation step described above, a halftone dot print formed by a plurality of central regions (c) and N types of regions (N is a natural number of 3 or more) is created. Although described above, the present invention is not limited to this, and the same applies to the method for producing a halftone dot printed matter formed by a plurality of two types of regions described in Japanese Patent Application Laid-Open No. 2009-202420. It goes without saying that the object similar to the present invention can be achieved by further including the background image generation step.

  The method for producing a halftone printed matter described above can be converted into halftone dot printed matter production software for execution by a computer program and stored in the recording medium (23).

  FIG. 15 shows an outline of a computer system (18) that can read software from a recording medium (23) stored after the above-described method for producing a halftone dot printed matter is converted into software, and execute it by a computer program. It is an example of the schematic diagram shown. The computer system (18) includes a main body (19) incorporating an arithmetic device, a disk drive device, and the like, a display (20) for displaying an image in accordance with an instruction from the main body (19), and a computer system (18). It consists of a recording medium (23) such as a keyboard (21) and a mouse (22) for inputting information, a CD-ROM, a flexible disk, a hard disk.

  As the recording medium (23) for storing the halftone dot printed material as software for executing the halftone dot printed material production method using a computer program, the above-mentioned flexible disk, CD-R, USB memory, hard disk, and main unit It is possible to use a volatile memory such as a RAM in (19). Furthermore, it is also possible to create a halftone print product software and store it in a database (24) connected to the computer system (18) by a wireless or wired information communication path. In either case, the program is called by the main body (19) and executed on the memory.

  Hereinafter, the halftone dot printed material having three regions, which is specifically manufactured according to the above-described embodiment, will be described in detail. For the halftone dot printed matter in Example 1, the first area (1) is 40 × 40 pixels using the halftone dot structure shown in FIG. 1B, and the central area (c) and the second area ( 2) was made 15 × 15 pixels, and the third region (3) was made 20 × 20 pixels. The printed material was produced using the image processing apparatus (4) shown in FIG.

  FIG. 16 shows a first image (a), a gray image (b), a second image (c), and a third image (d) in the first embodiment. FIG. 17 is a diagram showing each mask image and each image after the mask processing step in the first embodiment, and FIG. 18 is a flowchart showing a method for producing a halftone print in the first embodiment. Hereinafter, it produced according to the flowchart of FIG.

  First, the first original image, which is the basis of the first image, was input to the image input unit (6) (STEP 1). The first original image is a halftone dot in the final halftone dot printed material, the first image (FIG. 16A) that becomes a visible image in the diffused light region under the visible light source that is the first observation condition. This is an original image before being converted into an image. The first original image has a width of 4 cm × a height of 3 cm, a resolution of 300 DPI, an image composed of color information of cyan (C), magenta (M), yellow (Y), and black (K) did. Next, color conversion of the first original image was performed in the image processing unit (7), and all K components of the first original image were replaced with CMY components. There is no change in the appearance of the original image before and after the color conversion, but the first original image after the color conversion does not contain any K component. Thereafter, the first pixel image was generated by converting the resolution of the first original image after color conversion into 1200 DPI while maintaining the image size 4 cm wide × 3 cm high.

Next, the second original image, which is the basis of the second image, was input to the image input unit (6) (STEP1 ⁽²⁾ ). The second original image is converted into a halftone dot image in the final halftone dot printed matter, the second image (FIG. 16C) that becomes an image visible under the infrared light source that is the second observation condition. This is the previous original image. The second original image was a bitmap image having the same size as the first image (FIG. 16A), a width of 4 cm × a height of 3 cm, and a resolution of 72 DPI. Next, the image processing unit (7) performs halftone processing on the second original image by a method according to Halftone Type 16 of the Postscript halftone generation method, so that the size is 4 cm wide × 3 cm high. The image was converted into a black and white binary dot image with a resolution of 1200 DPI, and a second pixel image which was a black and white binary dot image was generated.

Next, the third original image, which is the basis of the third image, was input to the image input unit (6) (STEP1 ⁽³⁾ ). The third original image can be viewed in the final halftone print by changing the observation angle from the diffuse light region to the regular reflection light region with respect to the illumination light source at the fixed position, which is the third observation condition. A third image (FIG. 16D) that is an image is an original image before being converted into a halftone image. The third original image is the same as the first image (FIG. 16A) and the second image (FIG. 16C), and is a gray scale image having a width of 4 cm × a height of 3 cm and a resolution of 300 DPI. did. Next, in the image processing unit (7), halftone processing is performed on the third original image by a method according to Halftone Type 16 of the Postscript halftone generation method, so that the size is 4 cm wide × 3 cm high. The image was converted into a black and white binary dot image with a resolution of 1200 DPI, and a third pixel image which was a black and white binary dot image was generated.

Next, in order to easily generate each mask image, a gray image was generated (STEP 1 ⁽¹⁾ . First, the first pixel image, the second pixel image, and the third pixel image have the same size. Then, a first pixel image was selected, and then a gray image having the same size as the first pixel image and consisting of a plurality of pixels was generated based on the first pixel image. A solid image having an image size of 3 cm in height and a density of 50% was used.

  Next, reference points in each pixel image and gray image were set. Since the first pixel image, the second pixel image, and the third pixel image are all the same size, the four corners of each pixel image are set as reference points in each pixel image, and the reference points of each pixel image A reference point in the gray image was set at a common position.

  Next, the first threshold data generation means (9) in the mask image generation unit (8) is used for a size image of 40 × 40 pixels in which black is assigned to all pixels, using a format image prepared in advance. A first threshold image was generated. Further, a second threshold image having a size of 15 × 15 pixels in which white is assigned to all the pixels is generated by the second threshold data generation means (10) in the mask image generation unit (8). Further, a command conversion means (11) was used to embed an instruction conforming to Halftone Type 16 of the postscript halftone generation method for generating a halftone dot using the first threshold image and the second threshold image.

  Next, after the output result of the command conversion unit (11) is stored in a file by the halftone data storage unit (12), the raster processing unit (13) converts it into a 1200 DPI bitmap image having the same resolution as the first pixel image. The first mask image (FIG. 17A), which is a black and white binary image, was obtained by conversion (STEP 2). The first mask image is provided with a reference point at a position common to the reference point set for each pixel image.

  Next, in order to generate the second mask image, the range of 20 × 20 pixels in the first threshold image while the gray image (FIG. 16B) is input to the image input unit (6). A first threshold image of 40 × 40 pixels is generated in which white is assigned to all the pixels in the image, and black is assigned to all the other pixels, and the size in which all pixels are assigned black. A second threshold image of 15x15 pixels was generated.

Next, a command conversion means (11) was used to embed an instruction conforming to Halftone Type 16 of the Postscript halftone generation method for generating a halftone dot using the first threshold image and the second threshold image. After the output result of the command conversion unit (11) is stored in a file by the halftone data storage unit (12), the raster processing unit (13) converts it into a 1200 DPI bitmap image having the same resolution as the first pixel image. Thus, a second mask image (FIG. 17C), which is a black and white binary image, was obtained (STEP2 ⁽¹⁾ ). In the second mask image, a reference point is provided at a position in common with the reference point set for each pixel image.

  Next, the first mask image (FIG. 17A) and the second pixel image obtained by the image processing unit (7) are input to the mask processing unit (14), and the first mask image (FIG. 17A) is input. )) And the reference point of the second pixel image corresponding to the first mask image (FIG. 17A), and the first mask image (FIG. If the pixel constituting 17 (a)) is a black pixel, the pixel constituting the second pixel image is left, and if the pixel constituting the first mask image (FIG. 17 (a)) is a white pixel, the second pixel By making the pixels constituting the image white pixels, a second image (FIG. 17B) composed of a plurality of second halftone portions (2a) was generated (STEP 3). In the second image (FIG. 17B), a reference point is provided at a position common to the reference point set in each pixel image and each mask image.

Next, the second mask image (FIG. 17C) and the third pixel image obtained in the image processing unit (7) are input to the mask processing unit (14), and the second mask image (FIG. 17C) is input. )) And the second mask image (FIG. 17C) and the corresponding reference point of the third pixel image are combined, and the second mask image (FIG. 17 (c)) is a black pixel, the pixel constituting the third pixel image is left, and the pixel constituting the second mask image (FIG. 17 (c)) is a white pixel, the third pixel. A pixel constituting the image is a white pixel, thereby generating a third image (FIG. 17D) composed of a plurality of third halftone portions (3a) (STEP 3 ⁽²⁾ ).

  Next, the first pixel image, the second image and the third image after the mask processing step, and the first mask image and the second mask image are synthesized by matching the respective reference points, and the synthesized image is obtained. (STEP 4).

  First, a material having different characteristics that are visible depending on each observation condition, which forms the first halftone dot portion (1a), the second halftone dot portion (2a), and the third halftone dot portion (3a) was set. . In Example 1, since the first observation condition is set in the diffused light region under the visible light source, the materials that can be visually recognized by the first observation condition are cyan ink, magenta M, and yellow Y, which are process inks. did. Next, since the second observation condition was set under an infrared light source, the material visible under the second observation condition was black K, which is a process ink. Furthermore, since the third observation condition is set to change the observation angle from the diffuse light region to the regular reflection light region with respect to the illumination light source at a fixed position, the material that can be visually recognized by the third observation condition is made of metal. A glossy ink was used.

  Next, the color of the material forming each halftone dot portion and the background portion was set. First, after setting the color of cyan C (100%) + magenta M (100%) + yellow Y (100%) for the black pixels of the first mask image (FIG. 13A), all of them are replaced with that color. All the black pixels of the second mask image (FIG. 13C) are set to cyan C (20%) + magenta M (20%) + yellow Y (20%) + black K (80%). Substitute that color, set the black pixel of the second image after mask processing to the color of black K (100%), then replace it all with that color, and replace the black pixel of the third image after mask processing with metallic luster After setting a color for ink printing, it was replaced with that color.

  By replacing these colors, the second halftone dot portion (2a) and the second background portion (2b) are substantially the same color at the time of observation in the diffused light region under the visible light source, which is the first observation condition, and The third halftone dot portion (3a) and the third halftone background portion (3b) are visually recognized as substantially the same color, and the second halftone dot portion (2a) is observed under the infrared light source as the second observation condition. The (set color of the second image after mask processing) and the second background portion (2b) (set color of the first mask image) are visually recognized in different colors, and the third halftone dot portion (3a) ( Illuminated at a fixed position, which is a third viewing condition, in which the set color of the third image after mask processing) and the third background portion (3b) (set color of the second mask image) are visually recognized as substantially the same color. When the observation angle is changed with respect to the light source from the diffused light region to the regular reflection light region, the third halftone dot (3a) and the third background 3b) it is visually recognized in a different color, and the second halftone dot portion and (2a) a second background portion (2b) is set so as to be visible at a substantially uniform color.

FIG. 19 is a schematic diagram for combining image data in the first embodiment. Next, each colored image was input to the image composition unit (15), and then synthesized by combining the reference points of each image to generate a composite image (STEP 4). First, the first mask image is superimposed on the first pixel image by aligning the respective reference points (STEP 4-1), and further, the second image after the mask processing is further superimposed on the respective reference points. Were overlapped together (STEP4-2). In addition, the second mask image is superimposed on each reference point by aligning them (STEP 4-1 ⁽¹⁾ ), and further, the third image after mask processing is added to each reference point. The image data was completed by superimposing them together (STEP4-2 ⁽¹⁾ ) and generating a composite image. However, in the above-described image coloring and composition processing, the white pixel portion of the image to be overlaid is treated as transparent so that the lower image remains, and the other portions are overwritten with the image to be overlaid. did.

  The image data produced through the above steps includes three pieces of image information. Based on this image data, five printing plate surfaces of cyan (C), magenta (M), yellow (Y), black (K) and metallic gloss ink were outputted to produce a halftone print (STEP 5). At this time, cyan (C), magenta (M), and yellow (Y) used general process ink that transmits infrared rays, and black (K) used carbon black ink that absorbs infrared rays.

  The printing method was performed using an offset printing machine and using the above five printing plates. At the time of printing, the cyan C (100%) + magenta M (100%) + yellow Y (100%) portion and the black K (100%) portion on the halftone printed matter appear to be almost the same color with the naked eye. The ink density is adjusted, and the metallic gloss ink part and cyan C (20%) + magenta M (20%) + yellow Y (20%) + black K (80%) part are visually and infrared scattered. The ink density was adjusted so that it appeared almost the same color with light.

  The halftone dot printed matter produced by the above method was observed under predetermined observation conditions. First, in the diffused light region under the visible light source that is the first observation condition, the first image (FIG. 16A) is visually recognized by the naked eye, and further, the observation is performed under the infrared light source that is the second observation condition. Then, the second image (FIG. 16C) configured using carbon black is visually recognized, and the observation angle is set from the diffused light region to the illumination light source at a fixed position, which is the third observation condition. The third image (FIG. 16D) was visually recognized by changing the specular reflection light region, for example, by tilting the halftone print.

  For the halftone dot printed matter in Example 2, the first area (1) is 40 × 40 pixels using the halftone dot structure shown in FIG. 1B, and the central area (C) and the second area ( 2) was made 15 × 15 pixels, and the third region (3) was made 20 × 20 pixels. The printed material was produced using the image processing apparatus (4) shown in FIG.

  In Example 2, as in Example 1 described above, the first image (a), the gray image (b), the second image (c), and the third image (d) shown in FIG. Each mask image and the image after mask processing are used. In addition, about the preparation methods, it produced according to the flowchart which shows the preparation methods of the halftone printed matter in Example 2 shown in FIG.

  First, the first original image, which is the basis of the first image, was input to the image input unit (6) (STEP 1). The first original image is a halftone dot in the final halftone dot printed material, the first image (FIG. 16A) that becomes a visible image in the diffused light region under the visible light source that is the first observation condition. This is an original image before being converted into an image. The first original image has a width of 4 cm × a height of 3 cm, a resolution of 300 DPI, an image composed of color information of cyan (C), magenta (M), yellow (Y), and black (K) did. Next, color conversion of the first original image was performed in the image processing unit (7), and all K components of the first original image were replaced with CMY components. There is no change in the appearance of the original image before and after the color conversion, but the first original image after the color conversion does not contain any K component. Thereafter, the first pixel image was generated by converting the resolution of the first original image after color conversion into 1200 DPI while maintaining the image size 4 cm wide × 3 cm high.

Next, the second original image, which is the basis of the second image, was input to the image input unit (6) (STEP1 ⁽²⁾ ). The second original image is converted into a halftone dot image in the final halftone dot printed matter, the second image (FIG. 16C) that becomes an image visible under the infrared light source that is the second observation condition. This is the previous original image. The second original image was a bitmap image having the same size as the first image (FIG. 16A), a width of 4 cm × a height of 3 cm, and a resolution of 72 DPI. Next, the image processing unit (7) performs halftone processing on the second original image by a method according to Halftone Type 16 of the Postscript halftone generation method, so that the size is 4 cm wide × 3 cm high. The image was converted into a black and white binary dot image with a resolution of 1200 DPI, and a second pixel image which was a black and white binary dot image was generated.

Next, the third original image, which is the basis of the third image, was input to the image input unit (6) (STEP1 ⁽³⁾ ). The third original image can be viewed in the final halftone print by changing the observation angle from the diffuse light region to the regular reflection light region with respect to the illumination light source at the fixed position, which is the third observation condition. A third image (FIG. 16D) that is an image is an original image before being converted into a halftone image. The third original image is the same as the first image (FIG. 16A) and the second image (FIG. 16C), and is a gray scale image having a width of 4 cm × a height of 3 cm and a resolution of 300 DPI. did. Next, in the image processing unit (7), halftone processing is performed on the third original image by a method according to Halftone Type 16 of the Postscript halftone generation method, so that the size is 4 cm wide × 3 cm high. The image was converted into a black and white binary dot image with a resolution of 1200 DPI, and a third pixel image which was a black and white binary dot image was generated.

Next, in order to easily generate each mask image, a gray image was generated (STEP 1 ⁽¹⁾ . First, since the first pixel image, the second pixel image, and the third pixel image have the same size, The first pixel image was selected, and then a gray image having the same size as the first pixel image and consisting of a plurality of pixels was generated based on the first pixel image. A solid image having an image size of 3 cm and a density of 50% was used.

  Next, reference points in each pixel image and gray image were set. Since the first pixel image, the second pixel image, and the third pixel image are all the same size, the four corners of each pixel image are set as reference points in each pixel image, and the reference points of each pixel image A reference point in the gray image was set at a common position.

  Next, the first threshold data generation means (9) in the mask image generation unit (8) is used for a size image of 40 × 40 pixels in which black is assigned to all pixels, using a format image prepared in advance. A first threshold image was generated. Further, a second threshold image having a size of 15 × 15 pixels in which white is assigned to all the pixels is generated by the second threshold data generation means (10) in the mask image generation unit (8). Further, a command conversion means (11) was used to embed an instruction conforming to Halftone Type 16 of the postscript halftone generation method for generating a halftone dot using the first threshold image and the second threshold image.

  Next, after the output result of the command conversion unit (11) is stored in a file by the halftone data storage unit (12), the raster processing unit (13) converts it into a 1200 DPI bitmap image having the same resolution as the first pixel image. The first mask image (FIG. 17A), which is a black and white binary image, was obtained by conversion (STEP 2). The first mask image is provided with a reference point at a position common to the reference point set for each pixel image.

  Next, in order to generate the second mask image, the range of 20 × 20 pixels in the first threshold image while the gray image (FIG. 16B) is input to the image input unit (6). Generates a first threshold image of size 40x40 pixels in which all pixels within are assigned white and all other pixels are assigned black, and then all pixels are assigned black. A second threshold image of 15x15 pixels was generated.

Next, a command conversion means (11) was used to embed an instruction conforming to Halftone Type 16 of the Postscript halftone generation method for generating a halftone dot using the first threshold image and the second threshold image. After the output result of the command conversion unit (11) is stored in a file by the halftone data storage unit (12), the raster processing unit (13) converts it into a 1200 DPI bitmap image having the same resolution as the first pixel image. Thus, a second mask image (FIG. 17C), which is a black and white binary image, was obtained (STEP2 ⁽¹⁾ ). In the second mask image, a reference point is provided at a position in common with the reference point set for each pixel image.

  Next, the first mask image (FIG. 17A) and the second pixel image obtained by the image processing unit (7) are input to the mask processing unit (14), and the first mask image (FIG. 17A) is input. )) And the reference point of the second pixel image corresponding to the first mask image (FIG. 17A), and the first mask image (FIG. If the pixel constituting 17 (a)) is a black pixel, the pixel constituting the second pixel image is left, and if the pixel constituting the first mask image (FIG. 17 (a)) is a white pixel, the second pixel By making the pixels constituting the image white pixels, a second image (FIG. 17B) composed of a plurality of second halftone portions (2a) was generated (STEP 3). In the second image (FIG. 17B), a reference point is provided at a position common to the reference point set in each pixel image and each mask image.

Next, the second mask image (FIG. 17C) and the third pixel image obtained in the image processing unit (7) are input to the mask processing unit (14), and the second mask image (FIG. 17C) is input. )) And the second mask image (FIG. 17C) and the corresponding reference point of the third pixel image are combined, and the second mask image (FIG. 17 (c)) is a black pixel, the pixel constituting the third pixel image is left, and the pixel constituting the second mask image (FIG. 17 (c)) is a white pixel, the third pixel. A pixel constituting the image is a white pixel, thereby generating a third image (FIG. 17D) composed of a plurality of third halftone portions (3a) (STEP 3 ⁽²⁾ ).

  Next, the reference point in the first mask image (FIG. 17A) and the reference point in the second image after mask processing (FIG. 17B) are respectively combined and synthesized by XOR operation, and FIG. A first background image shown in a) was generated (STEP 3 ′).

Next, the reference point in the second mask image (FIG. 17C) and the reference point in the third image after mask processing (FIG. 17D) are respectively combined and synthesized by XOR operation, and FIG. The second background image shown in b) was generated (STEP 3 ′ ^{(1) ′} ). The first background image and the second background image also have reference points at the same positions as the reference points set in the first pixel image, the second pixel image, and the third pixel image, respectively.

  Next, the first pixel image, the second image and the third image after the mask processing step, and the first background image and the second background image are synthesized by matching the respective reference points, and the synthesized image is obtained. (STEP 4).

  First, a material having different characteristics that are visible depending on each observation condition, which forms the first halftone dot portion (1a), the second halftone dot portion (2a), and the third halftone dot portion (3a) was set. . In Example 1, since the first observation condition is set in the diffused light region under the visible light source, the materials that can be visually recognized by the first observation condition are cyan ink, magenta M, and yellow Y, which are process inks. did. Next, since the second observation condition was set under an infrared light source, the material visible under the second observation condition was black K, which is a process ink. Furthermore, since the third observation condition is set to change the observation angle from the diffuse light region to the regular reflection light region with respect to the illumination light source at a fixed position, the material that can be visually recognized by the third observation condition is made of metal. A glossy ink was used.

  Next, the color of the material forming each halftone dot portion and the background portion was set. First, all the black pixels of the first background image (FIG. 21A) are replaced with pixels of the color of cyan C (100%) + magenta M (100%) + yellow Y (100%), and the second background image ( All the black pixels in FIG. 22 (b) are replaced with pixels of the color of cyan C (20%) + magenta M (20%) + yellow Y (20%) + black K (80%). All black pixels in the second image were replaced with black K (100%) color pixels, and all black pixels in the third image after masking were replaced with metal gloss ink color pixels.

  By replacing these colors, the second halftone dot portion (2a) and the second background portion (2b) are substantially the same color at the time of observation in the diffused light region under the visible light source, which is the first observation condition, and The third halftone dot portion (3a) and the third halftone background portion (3b) are visually recognized as substantially the same color, and the second halftone dot portion (2a) is observed under the infrared light source as the second observation condition. The (set color of the second image after mask processing) and the second background portion (2b) (set color of the second background image) are visually recognized in different colors, and the third halftone dot portion (3a) ( Illumination at a fixed position, which is a third viewing condition, in which the set color of the third image after masking) and the third background portion (3b) (set color of the second background image) are visually recognized as substantially the same color. When the observation angle is changed from the diffused light region to the regular reflection light region with respect to the light source, the third halftone dot portion (3a) and the third background portion (3 ) It is visually recognized in different colors, and the second halftone dot portion and (2a) a second background portion (2b) is set so as to be visible at a substantially uniform color.

FIG. 22 is a schematic diagram for synthesizing image data in the second embodiment. Next, each colored image was input to the image composition unit (15), and then synthesized by combining the reference points of each image to generate a composite image (STEP 4). First, the first background image is overlaid on the first pixel image by aligning the respective reference points (STEP 4-1), and further, the second image after the mask processing is further superimposed on the respective reference points. Were overlapped together (STEP4-2). In addition, the second background image is superimposed on each other by aligning the respective reference points (STEP 4-1 ⁽¹⁾ ), and further, the third image after the mask processing is placed on each of the reference points. The image data was completed by superimposing them together (STEP4-2 ⁽¹⁾ ) and generating a composite image.

However, in the above-described image coloring and composition processing, the first background image is overlaid (STEP4-1) and the second background image is overlaid (STEP4-1 ⁽¹⁾ ). In the image, the white pixel portion was treated as transparent so that the lower image was left, and the other portions were overwritten with the upper image. At the time of overlaying the second image after the mask processing (STEP4-2) and at the time of overlaying the third image after the mask processing (STEP4-2 ⁽¹⁾ ), among the images to be superimposed on, By treating the pixel portion as transparent, the lower image was left, and in the other portions, the color of the pixel constituting the image to be overlaid was added to the color of the pixel constituting the image to be overlaid. Adding color here refers to adding values of cyan (C) density information, magenta (M) density information, and yellow (Y) density information of two pixels. However, when the density exceeds 100% as a result of addition, 100% is set as the density.

  Three pieces of image information are included in the image data of the composite image produced through the above steps. Based on this image data, five printing plate surfaces of cyan (C), magenta (M), yellow (Y), black (K), and metallic gloss ink were output to produce a halftone print (STEP 5). At this time, cyan (C), magenta (M), and yellow (Y) used general process ink that transmits infrared rays, and black (K) used carbon black ink that absorbs infrared rays.

  The printing method was performed using an offset printing machine and using the above five printing plates. At the time of printing, the cyan C (100%) + magenta M (100%) + yellow Y (100%) portion and the black K (100%) portion on the halftone printed matter appear to be almost the same color with the naked eye. The ink density is adjusted, and the metallic gloss ink part and cyan C (20%) + magenta M (20%) + yellow Y (20%) + black K (80%) part are visually and infrared scattered. The ink density was adjusted so that it appeared almost the same color with light. At the time of printing, each background portion was printed on the base material, and then each halftone dot portion was printed on each background portion, thereby producing a halftone dot printed matter.

  The halftone dot printed matter produced by the above method was observed under predetermined observation conditions. First, in the diffused light region under the visible light source that is the first observation condition, the first image (FIG. 16A) is visually recognized by the naked eye, and further, the observation is performed under the infrared light source that is the second observation condition. Then, the second image (FIG. 16C) configured using carbon black is visually recognized, and the observation angle is set from the diffused light region to the illumination light source at a fixed position, which is the third observation condition. The third image (FIG. 16D) was visually recognized by changing the specular reflection light region, for example, by tilting the halftone print.

  In addition, when performing offset printing, the five printing plate surfaces were printed slightly shifted from each other, but the shifted portions were not exposed because the first background image and the second background image were exposed. A halftone print was produced.

DESCRIPTION OF SYMBOLS 1 1st area | region 1a 1st halftone part 1b 1st background part 2 2nd area | region 2a 2nd halftone part 2b 2nd background part 3 3rd area | region 3 'A part of 3rd area | region 3a Third dot 3b Third background 4 Image processing device 5 Background image generator 6 Image input unit 7 Image processor 8 Mask image generator 9 First threshold data generator 10 Second threshold data generator 11 Command conversion means 12 Halftone data storage means 13 Raster processing means 14 Mask processing part 15 Image composition part 16 First threshold data 17 Second threshold data 18 Computer system 19 Main part 20 Display 21 Keyboard 22 Mouse 23 Recording medium 24 Database P1, P2, P3, P1 ′, P2 ′, P3 ′, p1 ′, p2 ′, p3 ′, P1 ″, P2 ″, P3 ″, P1 ′ ″, P2 ′ ″, P3 ′ ″ P1 '''', P2 '''', P3 '''' reference point c central region

Claims (4)

A printing region is formed in at least a part on the substrate, and the printing region includes a plurality of central regions, a plurality of first regions, a plurality of second regions, and a plurality of third regions, One central region is disposed so as to be surrounded by the region, the central region is smaller than the first region, and is disposed along the outer periphery of the first region, and the second region The region and the third region are disposed in the central region adjacent to the first region and / or the first region, and the central region includes the second region and the third region. The first region, the second region, and the third region are each composed of a halftone dot portion and a background portion, and the plurality of first regions, the plurality of second regions, A plurality of nets arranged in the region and the plurality of third regions, respectively. The first image, the second image, and the third image are respectively formed by the unit, and the second image and the third image are embedded in the first image, and the first region, The halftone dots in the second region and the third region are all formed of materials having different characteristics that can be visually recognized according to the first observation condition, the second observation condition, and the third observation condition, which are different observation conditions. The first image, the second image, and the third image are methods for producing a halftone print having a latent image that is visible under observation conditions corresponding to different characteristics of the material,
In each original image that is the basis of the first image, the second image, and the third image, at least three common points are set as reference points in each original image,
i) an image generation step of generating, from each of the original images, a pixel image having a reference point corresponding to the reference point of each of the original images and comprising a plurality of pixels, or
ii) an image generating step for generating, from each of the original images, a pixel image having a reference point corresponding to the reference point of the original image and each pixel image and a gray image including a plurality of pixels;
When the image generation step is i), a format image composed of a plurality of pixels in which arrangement positions of the plurality of first regions, the plurality of second regions, and the plurality of third regions are set. In the format image, only the pixels at the arrangement locations of the plurality of second regions and the pixels at the arrangement locations of the plurality of third regions are black pixels, and the pixels at the arrangement locations of the other regions are white pixels. A mask image generation step of generating each mask image having a reference point corresponding to the reference point of each original image, or
When the image generation step is ii), the minimum threshold value and / or the maximum threshold value corresponding to the brightness of the pixels constituting the gray image are set to the plurality of first regions, the plurality of second regions, and the Using a format image composed of a plurality of pixels in which a plurality of third region arrangement locations are set, only the pixels at the plurality of second region arrangement locations and the plurality of third regions in the format image A mask image generating step for generating each mask image having a reference point corresponding to the reference point of each original image, wherein only the pixel at the arrangement location is a black pixel and the pixel at the arrangement location of the other region is a white pixel; ,
The mask image of the two pixels at the same position by combining the reference point of each mask image and the reference points of the second pixel image and the third pixel line corresponding to the mask image, respectively. If the pixel constituting the mask image is a black pixel, the pixels constituting the second pixel image and the third pixel image are left, and if the pixel constituting the mask image is a white pixel, the second pixel image and By making the pixels constituting the third pixel image white pixels, the second image and the third region image each having a reference point corresponding to the reference point of each original image and comprising a plurality of halftone dot portions. A mask processing step for generating
Set the material and color having different characteristics that can be visually recognized according to each of the observation conditions, forming each of the halftone dots, and black pixels in the first image, the second image, and the third image , Replace with the color that forms each halftone dot set,
A material having a different characteristic from a material having a different characteristic that can be visually recognized according to each of the observation conditions forming each of the halftone dots, and each of the meshes under the observation conditions other than the respective observation conditions. Set a color that is the same color as the point part, and replace the black pixel in each mask image with the color that forms each set background part,
The first pixel image, the second image and the third image composed of the plurality of halftone dot portions generated in the mask processing step, and the respective mask images are synthesized by combining the respective reference points. An image composition process for generating a composite image;
A method for producing the halftone print, comprising the step of applying the composite image to the substrate by a predetermined method. In the case where the image generation step is ii), the mask image generation step includes:
The first region has the same shape and the same size as the first region, and at least a part of the second region and the third region are arranged in the first region. Among all the pixels that are arranged in the first region, all pixels corresponding to the second region and the third region have a lightness higher than that of the pixel that forms the gray image, A first highest threshold value setting step for setting a highest threshold value that is a higher brightness, and a pixel that is different from the pixel assigned the highest threshold value in the first highest threshold value setting step among the pixels constituting the first region. A first threshold data generation step including a first minimum threshold value setting step for setting a minimum threshold value that is lower in brightness than the lowest brightness value of the pixels forming the gray image;
The same shape and the same size as the central region, and at least a part of the second region and the third region are arranged in the central region, among the pixels constituting the central region, A maximum threshold value that is higher in brightness than the highest brightness of the pixels forming the gray image is set on all pixels corresponding to the second area and the third area arranged in the central area. The brightness of the pixel that forms the gray image in a pixel that is different from the pixel that is assigned the highest threshold in the second highest threshold setting step among the pixels that constitute the central region, and the second highest threshold setting step that is set A second threshold data generation step having a second minimum threshold setting step of setting a minimum threshold value that is lower than the lowest brightness of
A command conversion step of converting the first threshold data and the second threshold data into a predetermined command;
A halftone dot data storing step of combining the first threshold data, the second threshold data, and the gray image converted into the predetermined command, and storing them as halftone dot data;
Corresponds to the pixels for which the minimum threshold value is set in the first threshold data and the second threshold data among the pixels constituting the gray image which is a part of the halftone data for the stored halftone data. Raster processing for performing raster processing for converting all the pixels to be converted into white pixels, and converting all pixels corresponding to pixels having the highest threshold value in the first threshold data and the second threshold data into black pixels The method for producing a halftone dot printed matter according to claim 1, further comprising a step. Further comprising a background image generation step between the mask processing step and the image synthesis step,
In the background image generation step, the reference points in the mask images are combined with the reference points of the second image and the third image generated in the mask processing step corresponding to the mask images, respectively. If the two pixels at the same position are both black pixels or both are white pixels, the pixel is a white pixel, and if only one is a black pixel, the pixel is a black pixel. Generating a first background image and a second background image having points;
In the image composition step after the background image generation step, after replacing each mask image with each background image,
Set the material and color having different characteristics that can be visually recognized according to each of the observation conditions, forming each of the halftone dots, and black pixels in the first image, the second image, and the third image, Replace with the color that forms each halftone dot set,
A material having a different characteristic from a material having a different characteristic that can be visually recognized according to each of the observation conditions forming each of the halftone dots, and each of the meshes under the observation conditions other than the respective observation conditions. Set a color that is the same color as the point part, and replace the black pixel in each background image with the color that forms each set background part,
Combining the first pixel image, the second image and the third image generated in the mask processing step, and the background images together with their respective reference points to generate a composite image,
In the step of applying the composite image to the base material by a predetermined method, the background portion is printed on the base material, and the halftone dot portion is printed on the background portion. The method for producing a halftone dot printed material according to claim 1.   A recording medium storing halftone print production software for executing the method of producing a halftone print according to any one of claims 1 to 3 by a computer program.

Images