JP3889097B2 - Method and apparatus for creating crepe pattern - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present inventionMethod and apparatus for creating a crepe patternIn particular, the present invention relates to a method of creating a crepe pattern image applied to the surface of a building material or the like using a computer.
[0002]
[Prior art]
Various patterns are expressed by printing or embossing on the surface of building materials such as wallpaper and decorative boards. A typical example of a pattern that decorates the surface of such printed matter or embossed product is a grain pattern that uses the surface of natural wood as a motif, but a “crepe pattern” that represents a collection of fine folds is also widely used. ing. In particular, in the field of building materials, the embossing of this “crepe pattern” is used to express the surface texture of the so-called soft wood grain pattern.
[0003]
When printing or embossing a “crepe pattern”, an original image used as a document is required. As a method for obtaining such an original image, a method of taking a photograph of an actual crepe fabric is conceivable, but a designer usually draws a crepe pattern manually.
[0004]
[Problems to be solved by the invention]
The chirimen pattern is a particularly detailed pattern among the patterns. For this reason, the work of drawing with a manual drawing is very time and labor intensive. In addition, it is very difficult to correct the formation pattern of the wrinkles and the degree of intricacy of the pattern once drawn, and it is practically impossible to change the pattern. Also, when used for wallpaper with a relatively large area, it is often the case that the unit pattern is spatially repeated and used. In this case, a so-called repeatable pattern (upper and lower patterns) is used. And the pattern on the right side and the pattern on the left side must be drawn up), and when it is performed manually, a very advanced technique is required.
[0005]
Therefore, an object of the present invention is to provide a technique capable of creating a desired crepe pattern using a computer.
[0006]
[Means for Solving the Problems]
  (1) The first aspect of the present invention is:As the computer executes each stage of processing,In a method of creating a crepe pattern on a predetermined pattern creation surface,
  ComputerA skeletal figure generation stage that generates a large number of skeleton figures each consisting of a finite length line,
  ComputerA skeletal graphic placement stage for placing a large number of skeletal figures on the pattern creation surface;
  ComputerA reference distance value definition stage in which a large number of pixels are defined on the pattern creation surface, the distance between each pixel and the nearest skeleton figure is obtained, and the obtained distance value is defined as the reference distance value for that pixel. When,
  ComputerAssociate a reference distance value with a predetermined pixel valueBased on a predetermined pixel value table,A pixel value providing step of associating each pixel with a predetermined pixel value;
  ComputerAn image output stage for outputting an image composed of a set of pixels each associated with a predetermined pixel value as an image expressing a crepe pattern;
  Is to do.
[0007]
  (2) According to a second aspect of the present invention, in the method for creating a crepe pattern according to the first aspect described above,
  ComputerAt the skeletal figure generation stage, a plurality of n line segments each having a length determined by a random number are interconnected at an angle determined by each random number, thereby forming a broken line composed of n line segments. A polygonal line is used as one skeleton figure.
[0008]
  (3) According to a third aspect of the present invention, in the method for creating a crepe pattern according to the first or second aspect described above,
  ComputerAt the skeletal figure placement stage, define a large number of grid points regularly arranged on the pattern creation surface, and place each skeletal figure at each grid point, or set a value less than the preset maximum displacement The amount of displacement to be taken is determined for each individual lattice point using a random number, and each skeleton figure is arranged at a displacement point obtained by displacing each lattice point by this amount of displacement.
[0009]
  (4) According to a fourth aspect of the present invention, in the method for creating a crepe pattern according to the third aspect described above,
  ComputerAn orientation vector is defined for each skeleton figure, and when placing each skeleton figure, an arrangement angle that takes a value within the range of the preset maximum arrangement angle is determined using a random number, and the orientation vector of each skeleton figure is determined. Is arranged so as to be rotated so as to make the above-mentioned arrangement angle with respect to a predetermined reference direction.
[0010]
  (5) According to a fifth aspect of the present invention, in the method for creating a crepe pattern according to the first to fourth aspects described above,
  ComputerAs a pattern creation surface, using a finite plane whose contour is a figure that can fill the two-dimensional plane by arranging the same figure adjacently,
  ComputerAt the reference distance value definition stage, when calculating the distance for pixels near the contour of this finite plane, it is assumed that the same pattern creation surface is adjacent to the outside of the contour, and this adjacent pattern creation surface The distance is calculated in consideration of the skeleton figure inside.
[0011]
  (6) According to a sixth aspect of the present invention, in the method for creating a crepe pattern according to the first to fifth aspects,
  ComputerIn the pixel value provision stage, a pixel value table in which pixel values that periodically change with respect to changes in the reference distance value are used is used.
[0012]
  (7) According to a seventh aspect of the present invention, in the method for creating a crepe pattern according to the sixth aspect described above,
  ComputerThe binary value of the first pixel value and the second pixel value is used as the pixel value, and the range to be taken as the reference distance value is divided into a plurality of sections having a predetermined width. A pixel value table that associates pixel values and associates second pixel values with the even-numbered sections is used.
[0013]
(8) An eighth aspect of the present invention is an apparatus for creating a crepe pattern image on a predetermined pattern creation surface.
A parameter input means for inputting a parameter that defines a crepe pattern to be created;
Random number generating means for generating a random number within a predetermined numerical range;
A skeleton figure generating means for generating a skeleton figure consisting of a finite length line by applying a random number generated to an input parameter;
A skeletal graphic placement means for randomly placing a large number of skeletal figures on the pattern creation surface by applying a random number generated to the input parameter;
A reference distance value defining means for defining a large number of pixels on the pattern creating surface, obtaining a distance from the nearest skeleton figure for each pixel, and defining the obtained distance value as a reference distance value for the pixel When,
A pixel value table for associating a reference distance value with a predetermined pixel value, and based on the pixel value table, a pixel value providing means for associating a predetermined pixel value with each pixel;
Image output means for outputting an image composed of a set of pixels each having a predetermined pixel value associated therewith as an image expressing a crepe pattern;
Is provided.
[0014]
  As described above, created by the method and apparatus according to the present invention.Printed and embossed products with a crepe patternThenSkeletal figure consisting of finite length lines on the pattern forming surfaceButMany definitionsAndEach pixel on the pattern formation surface has a pixel value that is uniquely defined by the value of the distance from the nearest skeleton figure, and a pattern is formed by a set of these many pixels.Become.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
§0. Overview procedure
Hereinafter, the present invention will be described based on the illustrated embodiments. FIG. 1 is a flowchart showing the basic procedure of a method for creating a crepe pattern according to the present invention. Each of these procedures is executed using a computer, and is actually a process of handling numerical data and image data in a memory or a storage medium. The outline of this procedure is as follows. First, in step S1, a skeleton figure is generated. This skeleton figure is a figure that should be referred to as a “nucleus” of the crepe pattern to be generated, and it is a feature of the present invention to create a pattern in such a manner that the “core” is fleshed out. When a large number of skeleton figures are generated, these skeleton figures are arranged on the pattern creation surface in step S2. That is, a large number of skeleton figures are assigned to predetermined positions. However, in actual calculation processing, instead of taking the process of generating all the skeleton figures in step S1 and then arranging them in step S2, the arrangement is performed each time one skeleton figure is generated. The process is simpler if you take the process. Subsequently, a large number of pixels are defined on the pattern creation surface, and a predetermined reference distance value is defined for each of these pixels in step S3. Here, the reference distance value for a certain pixel is defined as “a distance from a skeleton figure that is closest to the pixel”. In the subsequent step S4, a specific pixel value is given to each pixel based on this reference distance value. In the final step S5, an image composed of these pixels is output as a crepe pattern image. Hereinafter, each of these steps will be described in detail.
[0016]
§1. Generation of skeletal figures
First, the skeleton figure generation process in step S1 will be described. The “skeletal figure” in the present invention means a “figure composed of a finite length line”. FIG. 2 shows an example of such a skeleton figure. The skeleton figure F shown here is a figure composed of a broken line formed by connecting the end points of four line segments L1 to L4. Both end points of this broken line are point D0 and point D4, which are bent at intermediate points D1 to D3. The intermediate points D1 to D3 are connection points of the individual line segments, and the branch angles θ1 to θ3 between the line segments can be defined at these intermediate points D1 to D3 (in this example, they are located on the left side of each intermediate point). The direction in which the line segment located on the right side extends in the counterclockwise angle value with respect to the direction in which the line segment extends (the direction of the broken line)). Such a skeleton figure F is a figure composed of lines of finite length (L1 + L2 + L3 + L4), and is one of skeleton figures suitable for use in the present invention.
[0017]
However, the skeleton figure that can be used for carrying out the present invention is not limited to such a skeleton figure composed of broken lines, and any form of skeleton figure may be used. For example, a simple line segment may be used as the skeleton figure, or a finite-length free curve as shown in FIG. 3 (a) may be used as the skeleton figure. It is also possible to use a triangle or other polygon as shown in FIG. 3 (b), a circle, an ellipse, a closed figure by a free curve, or the like. Further, as shown in FIG. 3 (c), a part of the line segments constituting the broken line may intersect.
[0018]
However, in order to increase the efficiency of computation processing by a computer, it is preferable to use a polygonal line as shown in FIG. 2 as a skeleton figure. In the case of such a skeleton figure composed of broken lines, the XY coordinate values of the five points D0 to D4 and the mutual connection order (D0 → D1 → D2 → This skeleton figure can be uniquely defined simply by preparing data indicating (D3 → D4 order). Also, when a large number of random skeleton figures are generated, it is more efficient to use a skeleton figure composed of broken lines. That is, a plurality of n line segments each having a length determined by a random number are interconnected at an angle determined by each random number, whereby a broken line composed of n line segments can be formed. For example, in the case of forming a broken line composed of four line segments as shown in FIG. 2, the length of each line segment L1 to L4 may be determined by a random number, and each branch angle θ1 to θ3 may be determined by a random number. . In this way, if a large number of skeleton figures are generated using random numbers, even if they are polygonal skeleton figures composed of the same four line segments, their forms and overall lengths vary greatly.
[0019]
Here, the center point and the orientation vector for such a skeleton figure composed of broken lines are defined as shown in FIG. First, the center point C of the regular circumscribing rectangle R of this skeleton figure (one set of opposite sides parallel to the X axis and another set of opposite sides parallel to the Y axis and circumscribing this skeleton figure) (Intersection of two diagonal lines) is defined as the center point of the skeleton figure itself. Further, a vector V from the start point D0 to the end point D4 of the polygonal line constituting this skeleton figure is defined as the orientation vector of this skeleton figure. The center point C of the skeleton graphic F is used as a representative point indicating the position of the skeleton graphic F in a later arrangement stage, and the orientation vector V is used as a vector indicating the orientation of the skeleton graphic F.
[0020]
§2. Arrangement of skeleton figure
Next, the skeleton graphic layout process in step S2 will be described. Here, a process of arranging a number of skeleton figures generated in step S1 on a predetermined pattern creation surface is executed. In general, when a natural pattern is artificially generated using a computer, a method of arranging individual elements using random numbers is often employed. However, as in the present invention, when generating a crepe pattern, it is not always appropriate to arrange the skeleton figure that becomes the “core” at random using random numbers. Actually, when the following process was carried out with the skeleton figure arranged at random, the created noodle pattern had unevenness on the whole, which is not desirable for expressing “uniformly distributed wrinkles”. As a result.
[0021]
  The inventor of the present application has found that it is preferable to represent “uniformly distributed wrinkles” when a regular arrangement is performed to some extent in the arrangement stage of the skeleton figure. Therefore, in the present embodiment, a large number of lattice points regularly arranged on the pattern creation surface are defined, and each skeleton figure is arranged on each lattice point. FIG. 5 shows a state in which a square lattice is defined on the pattern creation surface M and a large number of regularly arranged lattice points Q are defined, and FIG. 6 is generated at step S1 on each lattice point Q. The state which has arrange | positioned the made skeleton figure F is shown. When the individual skeleton figure F is arranged on each lattice point Q, the center point C of the skeleton figure described above may be located on the lattice point Q. At this time, eachSkeleton shapeIt is recommended that the direction of the is random to some extent. Specifically, it is preferable to perform an arrangement in which the orientation vector V of each skeleton figure is different for each skeleton figure. For example, every time one skeleton figure is arranged, an arbitrary arrangement angle φ within a range of −180 ° to + 180 ° is randomly generated using a random number, and the orientation vector V of the skeleton figure is set in a predetermined reference direction ( For example, the layout may be performed by rotating the skeleton figure in such a direction as to form the arrangement angle φ with respect to the Y-axis direction). Further, by restricting the range of the arrangement angle φ, it becomes possible to create a noodle pattern with overall orientation. For example, if an arbitrary arrangement angle φ is randomly generated using a random number within a range of −10 ° to + 10 °, each skeleton figure almost has a predetermined reference direction (for example, Y axis). The crepe pattern finally obtained is also a pattern having orientation along the reference direction.
[0022]
As described above, when a large number of skeleton figures are arranged on regular lattice points, it is possible to express “uniformly distributed wrinkles” with no unevenness on the whole. The center point of the skeleton figure takes a regular lattice arrangement, but the shape and total length of each skeleton figure are random, and the arrangement angle can also be set at random. Can create a crepe pattern that gives an impression. However, if you want to make the arrangement of individual skeletal figures more random and create a crinkle pattern with a high degree of freedom, it is also possible to use random numbers to displace individual grid points by a predetermined amount of displacement. is there. FIG. 7 shows a displacement point Q obtained by displacing each lattice point Q of the square lattice shown in FIG. 5 by a predetermined displacement amount determined at random.^*FIG. 8 shows such a displacement point Q.^*It is a figure which shows the state which has arrange | positioned each skeleton figure on the top.
[0023]
As described above, when the skeleton figure is arranged at random, coarse and uneven unevenness is generated in the finally obtained crepe pattern. For this reason, the displacement point Q^*It is preferable to provide a limit on the amount of displacement for obtaining the above. That is, a predetermined maximum displacement amount (for example, an amount that is 1/2 of the lattice interval) is set in advance, and a displacement amount that takes a value equal to or less than the maximum displacement amount is determined for each lattice point using a random number. What should I do? In addition, it is preferable that the displacement amount here includes information on the displacement direction so that the absolute value of the displacement amount and the direction thereof are random. Specifically, the displacement amount Δx in the X-axis direction and the displacement amount Δy in the Y-axis direction are combined to define the displacement amount in the form of (Δx, Δy), and each of Δx and Δy is separately assigned a random number. It should be defined by using.
[0024]
As a result of arranging a large number of skeleton figures in this way, even if adjacently arranged skeleton figures are overlapped in a plane, there is no problem in executing the following process. In the above example, a rectangular region is defined as the pattern creation surface M. However, in practice, any shape region may be defined as the pattern creation surface M. It is not limited to a plane. For example, when a pattern is mapped on the surface of a three-dimensional object, the pattern creation surface M can be defined on a curved surface.
[0025]
§3. Define reference distance values
Next, the reference distance value definition process in step S3 will be described. As a result of the processing in step S2 described above, a large number of skeleton figures F are arranged on the pattern creation surface M as shown in FIG. 6 or FIG. However, the skeleton figure F arranged here is merely a geometrical conceptual line, and is not a line having a thickness that can be recognized as a so-called image. The skeleton figure F is a conceptual component that functions as a “core” to the last, and in order to finally create a substantial pattern, an image composed of a large number of pixels must be created.
[0026]
Therefore, in step S3, first, a large number of pixels are defined on the pattern creation surface M. Here, the pixel array is defined in a very general vertical and horizontal matrix. The total number of pixels may be appropriately determined in consideration of the resolution of the crepe pattern to be created. For each pixel thus defined, a reference distance value is defined. Here, the reference distance value is a value defined as “distance from the skeleton figure that is closest to the pixel”. For example, consider the example shown in FIG. In this example, a state in which three skeleton figures F1 to F3 are arranged on the pattern creation surface (XY plane) is shown. A large number of pixels are defined on this pattern creation surface, and let's find the reference distance value by taking three of these pixels P1, P2 and P3 as an example. First, for the pixel P1, as shown in the figure, the nearest skeleton figure is F1, and the distance is d1 (here, the distance between the center point of each pixel and the skeleton figure). On the other hand, for the pixel P2, the nearest skeleton figure is F2, and the distance is d2. Further, for the pixel P3, the nearest skeleton figure is F3, and the distance is d3. Eventually, the reference distance values d1, d2, and d3 are defined for the pixels P1, P2, and P3, respectively.
[0027]
In this way, the reference distance value is defined for all the pixels constituting the pixel array on the pattern creation surface. In carrying out the subsequent processes, only the information of the reference distance value for each pixel is necessary, and the information for specifying the nearest skeleton figure is not necessary. Therefore, for example, for the pixel P1, it is sufficient if information that “the reference distance value is d1” is obtained, and information that “the nearest skeleton figure is F1” is not necessary. Thus, in step S3, one reference distance value is defined for each pixel, and as a result, a kind of scalar field having the reference distance value as a scalar value is formed on the pattern creation surface. . As will be described later, this scalar value is associated with a pixel value.
[0028]
By the way, when a pattern is applied to a printed matter or an embossed product having a relatively large area such as wallpaper, a method of repeatedly arranging unit patterns in space is often employed. For example, if a pattern composed of a square unit pattern with a side of 30 cm is created and this unit pattern is arranged adjacent to each other in 3 rows and 3 columns, a 90 cm square pattern as a whole can be obtained. However, when such a method is employed, it is necessary to create a so-called repeatable unit pattern in order to avoid discontinuity of the pattern at the boundary line of the unit pattern. For example, in the case of performing the repeated arrangement of 3 rows and 3 columns as described above, it is necessary to create a pattern in which the pattern on the upper side and the pattern on the lower side are continuous, and the pattern on the right side and the pattern on the left side are continuous. is there.
[0029]
In this way, when creating a noodle pattern that has the characteristics of a repeatable unit pattern in the end, the following measures may be taken in step S3. First, a finite plane whose contour is a figure that can fill the two-dimensional plane by arranging the same figure adjacently is used as the pattern creation surface. The pattern creation surface M having a rectangular outline as shown in FIGS. 5 to 8 is representative of such a finite plane. However, figures that can fill a two-dimensional plane include regular triangles, isosceles triangles, hexagons, etc. in addition to rectangles, and a finite plane with these figures as an outline may be used as a pattern creation surface. Absent. In the step of defining the reference distance value in step S3, when obtaining the distance for the pixels near the contour of the pattern creation surface, it is assumed that the same pattern creation surface is adjacently arranged outside the contour. The distance is obtained in consideration of the skeleton figure in the arranged pattern creation plane.
[0030]
FIG. 10 is a conceptual diagram of such a method. A pattern creation surface M0 shown in the center of the figure is a pattern creation surface that is a target for actually creating a crepe pattern. In this example, four pattern creation surfaces M1 to M4 are arranged around the periphery. These pattern creation surfaces M1 to M4 are all the same as the pattern creation surface M0, and a large number of skeleton figures are arranged in exactly the same manner as shown in FIG. 6, for example. ing. Here, when obtaining the distance for the pixels in the vicinity of the contour of the pattern creation surface M0 (the hatched region in the figure), the vicinity of the contour of the pattern creation surfaces M1 to M4 arranged adjacent to the outside of the contour (hatching is performed in the figure). The distance is calculated in consideration of the skeleton figure in the region. For example, when calculating the distance for the pixel Pz0 in the vicinity of the lower side of the pattern creation surface M0 (this is the same as the pixel Pz3 in the vicinity of the lower side of the pattern creation surface M3), the skeleton existing in the vicinity of the upper side of the pattern creation surface M4 The figure Fz4 (this is the same as the skeleton figure Fz0 existing in the vicinity of the upper side of the pattern creation surface M0) is also considered, and if the skeleton figure closest to the pixel Pz0 is in the vicinity of the upper side of the pattern creation surface M4. If the skeleton graphic Fz4 exists, the distance from the skeleton graphic Fz4 may be defined as the reference distance value for the pixel Pz0.
[0031]
If a reference distance value is defined for each pixel in the pattern creation surface M0 and a two-dimensional scalar field is formed by such a method, the two-dimensional scalar field becomes a repeatable field. That is, even when a large number of two-dimensional scalar fields are arranged adjacent to each other vertically and horizontally, discontinuity of scalar values does not occur at the boundary portion. For this reason, the crepe pattern finally created on the pattern creation surface M0 also becomes a repeatable pattern, and even when a large number of patterns are arranged adjacent to each other vertically and horizontally, discontinuity of the pattern at the boundary portion does not occur.
[0032]
§4. Adding pixel values
Thus, when the reference distance value is defined for each pixel, in step S4, a process of assigning a pixel value based on each reference distance value is performed. This process can be uniquely performed based on a pixel value table prepared in advance. The pixel value table is a table that defines the correspondence between the reference distance value and a predetermined pixel value, and is prepared in consideration of the tint pattern to be finally created, the shade difference, and the like. FIG. 11 is a diagram illustrating an example of such a pixel value table. In this example, the reference distance value is taken on the horizontal axis and the pixel value is taken on the vertical axis, and the correspondence between them is defined in the form of a function. The “pixel value table” in the present invention may be of any form as long as the table can associate the reference distance value and the pixel value as described above. It can be a table defined as a function expression.
[0033]
For example, if an 8-bit value from 0 to 255 is associated as a pixel value, each reference distance value is finally converted into an 8-bit pixel value, and an 8-bit pixel is formed on the pattern creation surface. A spiral pattern expressed by a set of pixels having values is created. If monochrome printing is performed using the 8-bit pixel value as a gradation value, a noodle pattern can be obtained with 256 gradations of gradation. Of course, if a pixel value is defined for each color element such as C, M, Y, etc., it is possible to obtain a colored crepe pattern. Further, it is not always necessary to define the gradation value as the pixel value, and a color number on a separately prepared color palette can be defined as the pixel value. For example, arbitrary 256 colors are defined on the color palette, color numbers from 0 to 255 are assigned to the defined colors, and color numbers from 0 to 255 are defined as pixel values. By doing so, it is possible to create a noodle pattern using the colors prepared on the color palette.
[0034]
In the pixel value table shown in FIG. 11, there is no particular regularity in the definition method of the pixel value. However, in creating a noodle pattern that emphasizes many overlapping folds, the reference distance value changes. It is preferable to use a pixel value table in which pixel values that periodically change are associated with each other. FIG. 12 is a diagram showing an example of such a pixel value table. The horizontal axis indicating the reference distance value is divided into four sections {circle around (1)} to {circle around (4)}, and exactly the same function is defined for each section. That is, a function of the pixel value that changes periodically with respect to the change of the reference distance value is defined.
[0035]
The pixel value table shown in FIG. 13 uses only two values “0” and “1” as pixel values, and associates pixel values that periodically change with respect to changes in the reference distance value. It is. That is, the range to be taken as the reference distance value is divided into a plurality of sections {circle around (1)}, {circle around (2)},... Having a predetermined width, and the pixel value “0” is associated with the odd-numbered sections. The pixel value “1” is associated with the section. When a pixel value is assigned using such a pixel value table, a very clear crepe pattern can be obtained as a binary image composed of white pixels and black pixels. FIG. 14 is a partial enlarged view of the noodle pattern obtained as such a binary image (strictly, although a curve appears at each corner, it is shown as a simple pattern composed of straight lines for the sake of illustration). It can be seen that a skeleton figure F as a nucleus is arranged in the center, and a pattern is formed so as to surround the skeleton figure F several times. The portion shown here is, so to speak, a pattern made up of pixels within the sphere of power of one skeleton figure F. In practice, a large number of skeleton figures with their own sphere of influence are arranged adjacent to each other. However, at the boundary of each power sphere, the pattern is naturally fused, and a natural crepe pattern with no sense of incongruity is formed as a whole.
[0036]
Such a noodle pattern consisting of a binary image is particularly suitable for use in an embossed product. For example, if this crepe pattern is expressed by embossing such that the white area shown in FIG. 14 is convex and the black area is concave, a texture suitable for a so-called soft wood grain pattern can be expressed. Can do. Here, the width of the white area and the width of the black area both correspond to the width of each divided section on the horizontal axis in the pixel value table shown in FIG. 13, and by adjusting the width, an arbitrary width can be obtained. A pattern can be formed.
[0037]
§5. Image output
The series of processes described so far are all executed as data processing inside the computer. When the pixel value assignment in step S4 is completed, raster image data representing a crepe pattern is created in the computer. . Therefore, in the final step S5, the raster image data is output. This image output may be performed in a form suitable for a subsequent printing process or embossing process. For example, an image can be physically output on a plate-making film, or can be output as raster image data to a printing plate apparatus. Alternatively, raster image data can be output to an external storage device and temporarily stored.
[0038]
One feature of the present invention is that correction can be easily made while observing the result thus output. For example, when it is desired to increase the density of the core skeleton figure, the density of the lattice points shown in FIG. In order to make it finer, the width of the division section of the pixel value table shown in FIG.
[0039]
Eventually, the image of the spiral pattern created by the method according to the present invention has the following characteristics. First, a large number of skeleton figures composed of lines of finite length are defined on the pattern forming surface. A large number of pixels are defined on the pattern forming surface, and each pixel has a pixel value that is uniquely defined by the value of the distance from the nearest skeleton figure. A crepe pattern formed by an image having such characteristics is suitable for creation using a computer and can be created by a relatively simple algorithm. In addition, the parameters can be easily set, and a pattern having a desired mode can be easily obtained.
[0040]
§6. Chirimen pattern creation device
FIG. 15 is a block diagram showing a basic configuration of a crepe pattern creating apparatus used for carrying out the above-described method. In practice, this apparatus is constructed by using a computer. Here, however, the function is focused and considered as a set of a plurality of functional blocks.
[0041]
First, the parameter input means 10 is a means for inputting a parameter that defines a crepe pattern to be created, and the operator inputs various parameters to the parameter input means 10. Specifically, a parameter indicating the size of the pattern creation surface, a parameter indicating the interval between grid points, a parameter indicating the shape of the skeleton figure, a parameter indicating the arrangement mode of the skeleton figure, a parameter indicating the resolution of the image, and a pixel value table Parameters to be defined are set.
[0042]
The random number generation means 20 has a function of generating a random number within a predetermined numerical range. This random number is used in the generation process and the arrangement process of the skeleton figure. The skeleton figure generating means 30 has a function of generating a skeleton figure composed of a finite length line by applying the random number generated by the random number generating means 20 to the parameter input to the parameter input means 10. Performs the processing described in §1 above. The skeleton graphic arrangement means 40 has a function of randomly arranging the skeleton graphic on the pattern creation surface by applying the random number generated by the random number generation means 20 to the parameter input to the parameter input means 10. Specifically, the processing described in §2 above is executed. When creating an actual program, if one skeleton figure is generated by the skeleton figure generating means 30, then the skeleton figure arranging means 40 performs a process of arranging it, and again the skeleton figure generating means 30 is generated. When the procedure of generating one skeleton figure and performing the process of arranging the skeleton figure by the skeleton figure arrangement means 40 is repeatedly executed, an efficient processing process can be realized.
[0043]
The reference distance value defining means 50 defines a large number of pixels on the pattern creation surface, obtains the distance between each pixel and the nearest skeleton figure, and uses the obtained distance value as the reference distance value for that pixel. Specifically, the processing described in the above section 3 is executed. Further, the pixel value giving means 60 has a pixel value table that associates a reference distance value with a predetermined pixel value, and has a function of associating a predetermined pixel value with each pixel based on this pixel value table. . Specifically, the processing described in §4 above is executed. The image output means 70 has a function of outputting an image made up of a set of pixels each associated with a predetermined pixel value as an image expressing a crepe pattern. Specifically, the processing described in §5 above Execute. Thus, an image G having a dust pattern is finally output.
[0044]
【Example】
Hereinafter, a method for creating a crepe pattern according to the present invention will be described based on more specific examples. This embodiment is an example of creating a crepe pattern consisting of a binary image, part of which is shown in FIG. FIG. 16 is a flowchart showing the procedure in the first half of this embodiment, and FIG. 17 is a flowchart showing the procedure in the latter half of this embodiment.
[0045]
The procedure in the first half is as follows. First, in step S11 in FIG. 16, various parameters are input. First, a horizontal dimension width indicating a size of an image to be created and a vertical dimension height are input. Next, the line width wl is input. This line width wl corresponds to the width of the black area or white area in the example shown in FIG. Subsequently, a square lattice interval ds to be input is a vertical and horizontal interval between lattice points Q as shown in FIG. Furthermore, the maximum value of the skeleton figure arrangement angle φmax and the maximum displacement dpmax of the grid points are input. The maximum value of the skeleton graphic arrangement angle φmax is a value indicating the upper limit of the arrangement angle (angle formed by the orientation vector V shown in FIG. 4 and the reference direction on the pattern creation surface) when the skeleton graphic is arranged. When it is set to = 10 °, the actual arrangement angle is limited within the range of −10 ° to + 10 °, and a crepe pattern having a considerably strong orientation is created. On the other hand, for example, when φmax = 90 ° is set, the arrangement angle is distributed in the range of −90 ° to + 90 °, and a pattern having substantially no orientation is formed. On the other hand, as shown in FIG. 7, the maximum displacement dpmax of the lattice point is obtained by displacing the regular lattice point Q by a predetermined displacement amount.^*Is a value indicating the upper limit of the amount of displacement when defining, and is a value indicating the maximum value of the amount of displacement in the X direction and the maximum value of the amount of displacement in the Y direction.
[0046]
In the subsequent step S12, the number of grid points in the vertical and horizontal directions is calculated. That is, the number of horizontal grid points nsx is calculated by nsx = width / ds, and the number of vertical grid points nsy is calculated by nsy = height / ds (in the flowchart, each variable has a predetermined numerical value). The general expression “: =” indicating the meaning of substituting is used to define an arithmetic expression). In the next step S13, strict recalculation of the lattice point interval is performed. That is, the lattice spacing ds input in step S11 is for a square lattice, but depending on the image size width × height, such a square lattice cannot arrange lattice points at exactly equal intervals. Therefore, in step S13, the exact lattice point interval dsx in the X-axis direction is defined as dsx = width / nsx, and the exact lattice point interval dsy in the Y-axis direction is redefined as dsy = height / nsy. Such a strict definition is particularly important when creating a crepe pattern as a repeatable unit image.
[0047]
In the next step S14, a parameter isx indicating the column number of the grid point under consideration and a parameter isy indicating the row number are set to an initial value 1, respectively. Therefore, at this time, first, the grid point in the first row and the first column is focused.
[0048]
In subsequent step S15, one skeleton figure is created. A specific procedure for creating a skeleton figure will be described later with reference to FIG. Here, it is assumed that one skeleton figure F as shown in FIG. 4 is created. In the following step S16, the arrangement angle φt of the skeleton figure and the displacements dpx and dpy of the lattice points are defined. First, the arrangement angle φt is defined by an arithmetic expression of φt = rnd (−1, + 1) * φmax. Here, rnd (a, b) means a random number within the range of a to b. For example, when φmax = 10 ° is set in step S11, φt is defined as an arbitrary angle within a range of −10 ° to + 10 °. Further, the displacement amount dpx in the X-axis direction is defined by an arithmetic expression of dpx = rnd (0,1) * dpmax, and the displacement amount dpy in the Y-axis direction is an arithmetic expression of dpy = rnd (0,1) * dpmax. Defined by For example, when dpmax = 1 mm is set in step S11, dpx and dpy are defined as arbitrary displacement amounts within the range of 0 mm to +1 mm. In the next step S17, a process of arranging the one skeleton figure created in step S15 under the conditions defined in step S16 is performed. The specific procedure of this arrangement process will be described later with reference to FIG.
[0049]
In this way, when one skeleton figure is arranged for one grid point, the arrangement for adjacent grid points in the same row is repeatedly executed through steps S18 and S19, and the arrangement processing for all the grid points in one row is performed. When completed, the same arrangement process is repeatedly executed for all rows through steps S20 to S22. This completes the first half of the process. Thus, for example, as shown in FIG. 8, a large number of skeleton figures are randomly arranged on the pattern creation surface M.
[0050]
On the other hand, the procedure in the second half is as follows. First, in step S23 of FIG. 17, various parameters are input. Some of the parameters input here are parameters input in the first half. That is, the horizontal dimension width indicating the size of the image to be created, the vertical dimension height, and the line width wl are the same as those input in step S11. The total number ns of skeleton figures arranged is equal to the number of grid points defined in the first half, and is obtained as ns = nsx * nsy. Further, the line segment number nl in one skeleton figure is a parameter input in the skeleton figure creation processing in step S15 (detailed procedure will be described later). For example, four skeleton figures F shown in FIG. When a skeleton figure is constituted by the line segments L1 to L4, nl = 4. The coordinates (x (i), y (i)) of the skeleton figure are parameters indicating the coordinates of each end point of the line segment constituting the skeleton figure. For example, in the case of the skeleton figure F as shown in FIG. , The coordinates of the start point D0 (x (0), y (0)), the coordinates of the intermediate point D1 (x (1), y (1)), and the coordinates of the intermediate point D2 (x (2), y (2)), the coordinates (x (3), y (3)) of the intermediate point D3, and the coordinates (x (4), y (4)) of the end point D4 are input. In step S23, a total of ns combinations of such coordinate values are input.
[0051]
Subsequently, in step S24, the parameter ix indicating the column number of the pixel of interest and the parameter iy indicating the row number are respectively set to the initial value 1. Therefore, at this time, first, the pixel in the first row and the first column is focused.
[0052]
In step S25, a reference distance value dmin for the pixel (ix, iy) under consideration is defined. That is, a process for obtaining a distance to the closest skeleton figure from the target pixel is performed. Details of this processing will be described later with reference to the flowchart of FIG. Subsequently, in step S26, it is calculated which section the reference distance value dmin defined for this pixel of interest belongs to. That is, first, a real number fval is obtained by an operation of fval = dmin / wl, and a value ival obtained by converting it into an integer is obtained. This value ival is a value indicating the section (1), (2),... In FIG. 13, and the line width wl corresponds to the width of this section. In the following step S27, it is determined whether the value ival is odd or even. If the value ival is odd, the pixel value “0” is assigned to the pixel of interest in step S28, and if it is even, the pixel of interest in step S29. The pixel value “1” is assigned to.
[0053]
In this way, when a predetermined pixel value is given to one pixel of interest, the pixel value giving process for adjacent pixels in the same row is repeatedly executed through steps S30 and S31, and the processing for all the pixels in one row is performed. When completed, the same pixel value provision processing is repeatedly executed for pixels in all rows through steps S32 to S33. When pixel values are assigned to all the pixels in this way, finally, pixel data is output in step S34.
[0054]
Next, the detailed procedure of the skeleton graphic creation process in step S15 (FIG. 16) described above will be described with reference to the flowchart shown in FIG. First, in step S41, the number nl of line segments in one skeleton figure, the maximum value Lmax and minimum value Lmin of the line segment length, and the maximum branch angle θmax are input as parameters. Here, the line segment number nl indicates the number of line segments constituting one skeleton figure. For example, the skeleton figure F shown in FIG. 2 is obtained by setting nl = 4. Further, the maximum value Lmax and the minimum value Lmin of the line segment length are parameters that define the maximum value and the minimum value of the lengths of the line segments L1 to L4 in the skeleton figure F shown in FIG. This parameter defines the maximum absolute value of the branch angles θ1 to θ3 between the line segments in the skeleton figure F shown in FIG. 2 (however, in this embodiment, −90 ° ≦ θ ≦ + 90 ° is set).
[0055]
In the next step S42, various variables are initialized. The variable il is a variable that indicates the number of the skeleton vertex (the end point of the line segment constituting the skeleton figure) that is currently focused on, even if the skeleton figure F shown in FIG. 2 is created by the initial setting of il = 0. For example, the vertex D0 is the skeleton vertex to which attention is first paid. The variable θ is an angle variable indicating the direction of a line segment extending from the current skeleton vertex. In this embodiment, the Y-axis direction is defined as θ = 0 °. Variables x (il) and y (il) are variables indicating the X coordinate value and the Y coordinate value of the skeleton vertex being focused. In this embodiment, an XY coordinate system having the first vertex as the origin is used. Yes. That is, if the skeleton figure F shown in FIG. 2 is created, the first vertex D0 is defined as the origin (0, 0).
[0056]
In step S43, the variable il indicating the skeleton vertex number is incremented by 1, and in the subsequent step S44, coordinate values (x (il), y (il)) of the new skeleton vertex are determined. That is, first, a new value of θ is randomly determined by the calculation θ + rnd (−1, + 1) * θmax, and the length L of the line segment is L = Lmin + rnd (0,1) * (Lmax−Lmin ) Is randomly determined. Eventually, the X coordinate value x (il) of the new skeleton vertex is obtained by adding L * sin θ to the X coordinate value x (il−1) of the old skeleton vertex, and the Y coordinate value y ( il) is obtained by adding L * cos θ to the Y coordinate value y (il−1) of the old skeleton vertex.
[0057]
The above processing is repeatedly executed through step S45 until il = nl, and one skeleton figure is created. For example, the skeleton figure F shown in FIG. 2 is created by repeating the above process four times.
[0058]
Next, a detailed procedure of the skeleton graphic arrangement process in step S17 (FIG. 16) described above will be described with reference to the flowchart shown in FIG. First, in step S51, the line segment number nl in one skeleton figure, the skeleton vertex coordinate sequence (x (i), y (i)), and the orientation vector orientation φs (for example, the skeleton figure shown in FIG. 4). If it is F, the angle between the orientation vector V and the Y axis) and the coordinates xc, yc of the center point of the skeleton figure (for example, if the skeleton figure F shown in FIG. The relative coordinates of the center point C), the arrangement angle φt of the skeleton figure, the lattice point coordinates (px, py), and the displacement amount (dpx, dpy) of the lattice point are input as parameters. Each of these parameters has been obtained in the process up to the previous stage.
[0059]
In the next step S52, the substantial rotation angle φ is obtained by the calculation φ = φt−φs. Here, φt is an arrangement angle defined in step S16, and φs is an angle indicating the direction of the orientation vector of the skeleton figure created in step S15. Since the skeleton figure created in step S15 is already inclined with respect to the Y axis by an angle φs, in order to arrange this skeleton figure at the arrangement angle φt, it substantially corresponds to a difference of φt−φs. What is necessary is just to rotate and arrange | position by an angle. The substantial rotation angle φ indicates this substantial rotation angle. In subsequent step S53, the substantial center point coordinates are obtained by the calculation of qx = px + dpx, qy = py + dpy. Here, (px, py) is the coordinate of the lattice point Q where the skeleton figure is to be placed, and (dpx, dpy) is the displacement amount in the direction of each coordinate axis. Therefore, the coordinate (qx, qy) is the displacement point Q^*The skeleton figure is the displacement point Q.^*The center point C may be arranged so as to overlap with each other.
[0060]
In the next step S54, a variable il indicating the number of the skeleton vertex is set to an initial value 0, and in step S55, calculation for rotating the substantial rotation angle φ is performed. That is, an operation for calculating new coordinate values x (il) and y (il) of the il-th skeleton vertex after being rotated by the substantial rotation angle φ is performed. First, the relative coordinate values xc and yc of the center point C are subtracted from the old coordinate values x (il) and y (il) to convert them into relative coordinate values based on the center point C. Subsequently, the position of the il-th skeleton vertex is expressed by polar coordinates (r, θ) with the center point C as the origin. Then, the value of θ is updated by adding the substantial rotation angle φ, and the polar coordinates (r, θ) after rotation are obtained. Finally, new coordinate values x (il) and y (il) after rotation are obtained by calculation of x (il) = r * cos θ and y (il) = r * sin θ. In step S56, the coordinate value of the il-th skeleton vertex when the center point C of the rotated skeleton figure F is superimposed on the real center point coordinates (qx, qy) is the new coordinate value. It is obtained as x (il) and y (il).
[0061]
Such processing is repeatedly executed up to the nl-th skeleton vertex through steps S57 and S58, and the arrangement processing of one skeleton graphic is completed.
[0062]
Next, a detailed procedure of the reference distance value definition process in step S25 (FIG. 17) described above will be described with reference to the flowchart shown in FIG. Here, a procedure for determining a reference distance value for one target pixel is shown. First, in step S61, the image size width and height, the coordinates of the pixel of interest (ix, iy: the center position of the pixel), the total number of skeleton figures ns, the number of line segments nl in one skeleton figure, and the coordinates of the skeleton figure (X (i), y (i)) are input as parameters. Each of these parameters has been obtained in the process up to the previous stage.
[0063]
In the next step S62, the variable is indicating the number of the skeleton figure to be noted among all ns pairs of skeleton figures is set to the initial value 1, and in step S63, infinity is set as the initial value of the reference distance value dmin to be obtained. In step S64, the is-th skeleton figure is focused. In step S65, the variable il indicating the number of the line segment to be noted among the nl line segments constituting the is-th skeleton figure is set to an initial value 1.
[0064]
Subsequently, in step S66, a distance dist between the focused line segment in the focused skeleton graphic (that is, the ilth line segment constituting the isth skeletal graphic) and the focused pixel is obtained. This distance dist can be obtained as the Euclidean distance between the point (ix, iy) and the line segment (x (il-1), y (il-1))-(x (il), y (il)). (In addition to the Euclidean distance, a 4-neighbor distance, 8-neighbor distance, octagonal distance, etc. of the digital image may be used). However, in this embodiment, in order to create a crepe pattern that can be used as a so-called repeatable unit pattern, as shown in FIG. The distance from the nearest skeleton figure is calculated. However, the calculation shown in step S66 uses a slightly elaborate technique for efficient calculation. That is, the concept described with reference to FIG. 10 performs an operation considering the skeleton figures on the five pattern creation surfaces M0 to M5 in order to obtain a reference distance value for a predetermined pixel in the pattern creation surface M0. However, the calculation performed in step S66 is to obtain the distance from the single skeleton figure on the pattern creation surface M0 for the same pixels on the five pattern creation surfaces M0 to M5. It is a calculation. Five distance values dist0 to dist4 are obtained by the five arithmetic expressions shown in step S66, where dist0 represents the distance between the pixel in the pattern creation surface M0 and the skeleton figure in the pattern creation surface M0. , Dist1 indicates the distance between the pixel in the pattern creation surface M1 and the skeleton graphic in the pattern creation surface M0, and dist2 indicates the distance between the pixel in the pattern creation surface M2 and the skeleton graphic in the pattern creation surface M0, and dist3 Indicates the distance between the pixel in the pattern creation surface M3 and the skeleton graphic in the pattern creation surface M0, and dist4 indicates the distance between the pixel in the pattern creation surface M4 and the skeleton graphic in the pattern creation surface M0. In step S67, the minimum value among dmin, dist0, dist1, dist2, dist3, and dist4 is defined as a new dmin.
[0065]
Such processing is repeatedly executed for all the line segments of the ith skeleton figure of interest through steps S68 and S69, and is further repeatedly executed for all skeleton figures via steps S70 and S71. Finally, in step S72, it is defined as a reference distance value for obtaining dmin at that time.
[0066]
In short, in order to define the reference distance value for one pixel, the procedure shown in the flowchart of FIG. 20 obtains all the distances between this pixel and all the line segments constituting the entire skeleton figure, and the smallest among them is determined. This is a procedure in which the distance is used as a reference distance value. In particular, the additional calculation for constructing a repeatable unit picture need only be executed for pixels near the contour shown by hatching in FIG. 10, but in the above procedure, it is executed for all pixels. It will be. Such a so-called “brute force” calculation method is never an efficient method, but the algorithm is very simple, so it is sufficiently practical today that the CPU processing speed is increasing. It is a method with.
[0067]
Finally, FIGS. 21 and 22 show specific examples of a spiral pattern created by the method according to this embodiment. FIG. 21 shows the result of arranging the skeleton figure with a certain degree of orientation (set the maximum value of the skeleton figure arrangement angle φmax = 30 °), and the noodle pattern is formed with the orientation in the vertical direction of the figure. ing. On the other hand, FIG. 22 shows the result of arranging the skeleton figure without orientation (set to φmax = 90 °), and the core skeleton figure is randomly oriented in an arbitrary direction, and a noodle pattern is formed. ing.
[0068]
In addition, the relationship between the characteristic of the finally formed crepe pattern and the parameters is as follows.
(1) Density of individual dust noodle elements → square lattice spacing ds
(2) Size of each crepe element → Line segment length Lmin, Lmax
(3) Orientation of individual crepe elements → Maximum value of skeleton figure arrangement angle φmax
(4) Uniformity of individual dusting elements → Maximum displacement of lattice points dpmax
(5) Degree of shrinkage of individual crepe elements → maximum branch angle θmax.
[0069]
【The invention's effect】
As described above, according to the present invention, a desired dust pattern can be easily created using a computer.
[Brief description of the drawings]
FIG. 1 is a flowchart showing a basic procedure of a method for creating a crepe pattern according to the present invention.
FIG. 2 is a diagram showing an example of a skeleton figure that is the core of a crepe pattern in the crepe pattern creation method according to the present invention.
FIG. 3 is a diagram showing still another example of a skeleton figure that is the core of a crepe pattern in the crepe pattern creation method according to the present invention.
4 is a diagram showing a method of defining a center point C and an orientation vector V for the skeleton figure formed by the broken lines shown in FIG. 2. FIG.
FIG. 5 is a diagram showing a square lattice defined on a pattern creation surface M in the method for creating a crepe pattern according to the present invention.
6 is a diagram showing a state in which a skeleton figure F is arranged on each lattice point Q of the square lattice shown in FIG.
7 shows a displacement point Q obtained by randomly displacing each lattice point Q of the square lattice shown in FIG.^*It is a figure which shows the state which formed.
8 shows each displacement point Q shown in FIG.^*It is a figure which shows the state which has arrange | positioned the skeleton figure F on each.
FIG. 9 is a diagram for explaining a method of defining reference distance values of pixels P1 to P3 in a state where three skeleton figures F1 to F3 are arranged on a pattern creation surface (XY plane).
FIG. 10 is a diagram for explaining a method of defining a reference distance value in the case of creating a noodle pattern with a characteristic as a finally repeatable unit pattern.
FIG. 11 is a diagram showing an example of a pixel value table used in the method for creating a crepe pattern according to the present invention.
FIG. 12 is a diagram showing an example of a periodic pixel value table used in the method for creating a crepe pattern according to the present invention.
FIG. 13 is a diagram illustrating an example of a pixel value table used when creating a noodle pattern composed of binary images.
FIG. 14 is a partial enlarged view of a noodle pattern obtained as a binary image by the method according to the present invention.
FIG. 15 is a block diagram showing a basic configuration of a crepe pattern creating apparatus according to the present invention.
FIG. 16 is a flowchart showing a procedure in the first half of a method for creating a crepe pattern according to an embodiment of the present invention.
FIG. 17 is a flowchart showing a procedure in the latter half of the method for creating a crepe pattern according to an embodiment of the present invention.
FIG. 18 is a flowchart showing a procedure of a skeleton graphic creating process in the method for creating a crepe pattern according to one embodiment of the present invention.
FIG. 19 is a flowchart showing the procedure of the skeleton graphic arrangement process in the method for creating a crepe pattern according to one embodiment of the present invention.
FIG. 20 is a flowchart showing a procedure of a reference distance value definition process in the method for creating a crepe pattern according to an embodiment of the present invention.
FIG. 21 is a diagram showing an example of a noodle pattern actually created by the method according to an embodiment of the present invention.
FIG. 22 is a diagram showing another example of a noodle pattern actually created by the method according to an embodiment of the present invention.
[Explanation of symbols]
10: Parameter input means
20: Random number generation means
30. Skeletal figure generating means
40. Skeletal figure arrangement means
50: Reference distance value defining means
60... Pixel value giving means
70: Image output means
C: Center point of skeleton figure
D0 to D4 ... Skeletal vertex (end point of line segment)
d1 to d3 ... Reference distance value (distance to the nearest skeleton figure)
F, F1-F3 ... Skeletal figure
Fz0, Fz3 ... Skeletal figures near the contour
G ... Image with a crepe pattern
L1 to L4: Individual line segments constituting the skeleton figure
M, M0 to M4 ... Pattern creation surface
P1-P3 ... Pixel
Pz0, Pz3: Pixels near the contour
Q ... Lattice points
Q^*... Displacement point
R ... Regular circumscribed rectangle of skeleton figure
V ... Orientation vector of skeleton figure
θ1 to θ3 ... Branch angle of line

Claims (8)

A method of creating a crepe pattern on a predetermined pattern creation surface by a computer executing each stage of processing ,
A skeletal figure generation stage in which a computer generates a number of skeleton figures each consisting of a finite length line;
A skeleton graphic arrangement stage in which the computer arranges the skeleton graphic on the pattern creation surface;
A computer defines a number of pixels on the pattern creation surface, determines the distance between each pixel and the nearest skeleton figure, and defines the calculated distance value as the reference distance value for that pixel. A distance value definition stage;
A pixel value assigning step in which a computer associates each pixel with a predetermined pixel value based on a predetermined pixel value table associating the reference distance value with a predetermined pixel value;
Computer, an image in which a predetermined pixel value, each consisting of a set of pixels associated, and an image output step of outputting an image representing the crepe pattern,
A method for producing a crepe pattern characterized by comprising: The creation method according to claim 1,
At the stage of generating a skeletal figure, a plurality of n line segments each having a length determined by a random number are interconnected at an angle determined by each random number to form a polyline consisting of n line segments. A method for creating a crepe pattern, wherein the polygonal line is a single skeleton figure. In the creation method according to claim 1 or 2,
The computer defines a large number of grid points regularly arranged on the pattern creation surface at the skeletal figure placement stage, and places each skeletal figure at each grid point or less than the preset maximum displacement The amount of displacement is determined by using a random number for each lattice point, and each skeleton figure is arranged at a displacement point obtained by displacing each lattice point by the amount of displacement. How to create The creation method according to claim 3,
When a computer defines an orientation vector for each skeleton figure and places each skeleton figure, it determines a placement angle that takes a value within the range of the preset maximum placement angle using a random number, A method for producing a crepe pattern, wherein the orientation vector is rotated and arranged so as to form the arrangement angle with respect to a predetermined reference direction. In the preparation method in any one of Claims 1-4,
The computer uses a finite plane whose contour is a figure that can fill the two-dimensional plane by arranging the same figure adjacently as the pattern creation surface,
When the computer calculates the distance for the pixels near the contour in the reference distance value definition stage, it is assumed that the same pattern creation surface is adjacently arranged outside the contour, and this adjacently arranged pattern creation is performed. A method for creating a crepe pattern characterized by obtaining a distance in consideration of an in-plane skeleton figure. In the preparation method in any one of Claims 1-5,
A method for creating a crepe pattern, wherein a computer uses a pixel value table in which pixel values that periodically change with respect to changes in a reference distance value are used in a pixel value provision stage. The creation method according to claim 6,
The computer uses binary values of the first pixel value and the second pixel value as pixel values, divides the range of the reference distance value into a plurality of sections having a predetermined width, and for odd-numbered sections A method for creating a crepe pattern, characterized by using a pixel value table that associates first pixel values and associates second pixel values with even-numbered sections. An apparatus for creating a crepe pattern image on a predetermined pattern creation surface,
A parameter input means for inputting a parameter that defines a crepe pattern to be created;
Random number generating means for generating a random number within a predetermined numerical range;
Skeleton graphic generating means for generating a skeleton graphic consisting of a finite length line by applying the random number to the parameter;
Skeleton graphic arrangement means for causing the random number to act on the parameter, and arranging a large number of the skeleton figures at random on the pattern creation surface;
A reference distance value definition that defines a large number of pixels on the pattern creation surface, obtains a distance from the nearest skeleton figure for each pixel, and defines the obtained distance value as a reference distance value for the pixel Means,
A pixel value table that associates the reference distance value with a predetermined pixel value, and based on the pixel value table, a pixel value providing unit that associates a predetermined pixel value with each of the pixels;
Image output means for outputting an image composed of a set of pixels each having a predetermined pixel value associated therewith as an image expressing a crepe pattern;
A device for producing a crepe pattern.

Images