WO2008056673A1 - Method for creating pseudo-skin image having fractal dimension, method for examining skin by using pseudo-skin image created by the method, and skin simulation method - Google Patents

Abstract

A technique of creating a desired pseudo-skin image, a technique of simulating a pseudo-skin image by varying the reflection condition, and a technique of examining a skin by using the pseudo-skin image as a reference image. A pseudo-skin image creating method comprises an S1 step of selecting a 2.0 to 3.0 fractal dimension value and creating a pseudo skin roughness by using a signal representing a fractional Brownian motion having the fractal dimension value, a S2 step of simulating reflection of light from the surface of the pseudo-skin roughness, and a S3 step of displaying the simulation results.

Description

 Specification

 Method for forming pseudo skin image having fractal dimension, skin discrimination method using pseudo skin image formed by the method, and skin simulation method

 Technical field

 [0001] The present invention relates to a method for forming a pseudo skin image based on fractal properties, a pseudo skin image formed by the method, and a skin discrimination method using the pseudo skin image. More specifically, the texture of the simulated skin image changes due to changes in the light reflection conditions on the surface of the artificial skin with a fractal dimension of 2.0 to 3.0, and the fractal dimension of the simulation image also changes. The present invention relates to a method for forming a pseudo skin image utilizing the above, a pseudo skin image formed by the method, and a method for distinguishing skin by using the pseudo skin image as a standard image. Background art

 Recognizing that the skin is beautiful by a third party is one of the great wishes of many people as well as women. For this reason, research and development of cosmetics and beauty methods to make the skin look beautiful is being actively conducted. In addition, the skin condition varies greatly depending on the individual, and also changes depending on the aging and living environment. Therefore, in order to appropriately select the type of cosmetics, makeup method, skin care method, etc. It is also necessary to develop technology to objectively determine how the skin looks like to a third party. As a technique for objectively evaluating such skin, the device that measures the three-dimensional shape data of the replica of the skin surface (see Patent Documents 1 and 2) and the unevenness of the skin replica are captured with a surface roughness meter, A method (see Patent Document 3) for performing spectral analysis to evaluate the goodness of the skin surface state is disclosed.

[0003] In an objective judgment such as force, a large number of specimens showing various skin states are required, and at the same time, it is indispensable to select a specimen that serves as a reference for such skin. Furthermore, rather than selecting a skin sample that will serve as the standard, the ability to arbitrarily create the desired skin sample and use it as a standard will be useful for researching skin, evaluating skin, and exhibiting at sales sites. There was a strong demand for extremely high utility value. Examples of techniques for creating such a strong skin include in vivo methods for producing rough skin models and aging skin models by irradiating animal skin with ultraviolet rays (see Patent Documents 4 and 5), and skin replicas. In vitro method (see Patent Document 6) ), An apparatus for creating a three-dimensional image of skin using three-dimensional data of a skin replica (see Patent Document 7), etc., is disclosed, but all of these techniques for creating a desired skin condition are completely known. It is not done.

 [0004] On the other hand, among the factors related to whether or not the skin is beautiful, the conditions for observing the skin are extremely important. For example, when observing the skin, the viewing angle is slightly different, making it brighter. I feel hungry or dark. In addition, even if the viewing direction is constant, the appearance of the color is also different depending on the direction (light source position) where the light (viewpoint) strikes. Because of the power, in image production and simulation, from the viewpoint of power, the viewpoint (diffuse reflection and specular reflection coefficients differ depending on the viewpoint, and the way they look is greatly different), the viewpoint outside the light source and the object, Research and development of more accurate, real and practical methods are being conducted. For example, when creating computer graphics (hereinafter referred to as “CG”) images, it is possible to easily set surface texture parameters such as diffuse reflectance! / Without the need (see Patent Document 8), and 3D simulation of textile products. Disclosed are methods for automatically creating map data by extracting optical attributes such as diffuse reflectance and transmittance (see Patent Document 9)!

[0005] On the other hand, in recent years, attention has been focused on geometrical concepts used for self-similar figures called fractals. In addition, it has become known that there are many things that have a fractal shape in nature. There has been reported a method for determining a specific state in a living body by calculating a fractal dimension, which is one means of expressing the shape of a fractal property. For example, an automatic detection system for malignant cells using fractal analysis (Patent Document 10). Evaluation of skin melanin distribution from the correlation between the distribution of pigments such as melanin and the fractal dimension of the brightness of the pixels constituting the skin image. (Patent Document 11), it has been reported that skin age may be estimated using the fractal dimension of skin property values as an index (Patent Document 12). In addition, as a method for creating texture and skin condition, a method for creating a wood grain pattern pattern using fractals (Patent Document 13), a method for generating a video image of a microscopic texture using fractals (Patent Document 14), etc. However, no technology has yet been found to arbitrarily produce the desired skin condition. In addition, there is no mention of the relationship between such fractal technology and the reflection coefficient of diffuse reflection and specular reflection. Patent Document 1: Japanese Patent Laid-Open No. 05-146412

Patent Document 2: Japanese Patent Laid-Open No. 05-329133

Patent Document 3: Japanese Patent Laid-Open No. 04-305113

Patent Document 4: Japanese Patent Laid-Open No. 05-244842

Patent Document 5: Japanese Patent Laid-Open No. 05-284879

Patent Document 6: Japanese Patent Laid-Open No. 05-317292

Patent Document 7: Japanese Unexamined Patent Application Publication No. 2006-223366

Patent Document 8: Japanese Patent Laid-Open No. 7-320090

Patent Document 9: Japanese Patent Laid-Open No. 2003-036449

Patent Document 10: Special Table 2001 — 512824

Patent Document 11: Japanese Unexamined Patent Publication No. 2000-135207

Patent Document 12: Japanese Unexamined Patent Application Publication No. 2007-050158

Patent Document 13: Japanese Patent Application Laid-Open No. 08-022538

Patent Document 14: Japanese Patent Application Laid-Open No. 07-264473

Non-patent literature 1: Yuji Ogasawara, 3D CG introduction, Morikita Publishing, 1999

Disclosure of the invention

The invention is going to be solved Mouth Tf ei

Under such circumstances, the present inventors pay attention to the fractal characteristics of the skin, and the relationship between the skin property values and the visual evaluation values such as the beauty and three-dimensional shape of the skin by a third party is simple and objective. Has found a method for estimating visual evaluation values by a third party, and has filed a patent application. In other words, the process of obtaining at least one color system image signal of the skin surface image, and calculating the fractal dimension of the distribution on the image for at least one component constituting the color system image signal. And substituting the calculated fractal dimension into a regression equation that represents the relationship between the fractal dimension of the distribution of the component prepared in advance and the visual evaluation value of the three-dimensional shape of the skin surface, and visually evaluating the three-dimensional shape of the skin surface. And a method for estimating a visual evaluation value of the three-dimensional shape of the skin surface including the step of obtaining the value (Japanese Patent Application No. 2006-046654). And a step of obtaining an image signal of at least one color system of an image on the surface of the skin, and a fractal dimension of distribution on the image for at least one component constituting the image signal of the color system. Substituting the calculated fractal dimension into the regression equation representing the relationship between the step of calculating and the fractal dimension of the distribution of the component prepared in advance and the visual evaluation value of the beauty of the skin, and calculating the visual evaluation value of the skin beauty And a method for estimating a visual evaluation value of the beauty of the skin including the obtaining step (Japanese Patent Application No. 2006-046659). In the subsequent study, I realized the possibility of using a fractal technique such as force to create a pseudo-skin image having an arbitrary fractal dimension, that is, a pseudo-skin image having an arbitrary beauty. We also noticed that the surface light reflection coefficients (diffuse reflectance and specular reflectance) may contribute to the fractal nature of the pseudo-skin image in a pseudo-skin image with a fractal dimension such as force. . On the other hand, there is no known method for creating a pseudo-skin image that focuses on the fractal characteristics of the skin, and the fractal dimension of the reflective surface varies depending on the reflection coefficient such as diffuse reflectance and specular reflectance. It was not known at all that it changed and the appearance and beauty of the skin surface changed.

 [0008] The present invention has been made under such circumstances, and provides a technique for producing a pseudo skin image having a fractal dimension, and simulates a pseudo skin image by changing reflection conditions. It is an object of the present invention to provide a technique, and further to provide a technique for distinguishing skin by using the pseudo skin image as a standard image.

 Means for solving the problem

 [0009] In view of such a situation, the present inventors have intensively studied for a method for forming a fake skin image having fractal properties, and as a result, have obtained a method for forming a fake skin image having a fractal dimension. A process of creating a pseudo skin undulation based on a fractional brown motion signal, a step of simulating light reflection on the surface of the pseudo skin undulation, and a step of displaying the simulation result. We have discovered a technology for forming a pseudo skin image and have completed the invention. That is, the present invention is as follows.

[0010] (1) A method for forming a pseudo skin image, wherein a fractal dimension value of 2.0 to 3.0 is selected, and pseudo skin relief is generated by a signal of a fractional brown motion having the fractal dimension value. A method for forming a pseudo skin image, comprising: a step S1 to be manufactured, a step S2 for performing light reflection simulation on the surface of the artificial skin relief, and a step S3 for displaying the simulation result. (2) The image forming method according to claim 1, wherein the step S2 includes a step S2-1 in which simulation is performed by changing a height of the skin relief on the surface of the pseudo skin relief. (3) The S2 step according to claim 1 or 2, wherein the S2 step includes a S2-2 step of performing simulation by changing a diffuse reflectance and a specular reflectance of light with respect to the surface of the pseudo undulation. Image forming method.

 (4) Claims !! to 3! /, A pseudo skin image formed by any method.

 (5) Use at least two values of the fractal dimension value of the pseudo-skin image formed by the method of claim 3 and the diffuse reflectance value and specular reflectance value of light set in step S2-2. V or a graph or matrix to be created.

 (6) A method for distinguishing skin using the pseudo skin image according to claim 4, wherein a plurality of pseudo skin images having different fractal dimensions are used as standard images, and an actual skin image obtained from the skin of the subject. Comparing the image with the standard image, selecting a standard image that approximates the actual skin image, and distinguishing the fractal dimension of the standard image from the actual skin fractal dimension

, Skin discrimination method.

 (7) A simulation program for forming a simulation image of skin by a programmed computer. The computer inputs a fractal dimension value of 2.0 to 3.0, and the fractional brown having the fractal dimension value is input. A simulation program for functioning as a means for creating a pseudo skin relief from a motion signal, a means for simulating light reflection on the surface of the pseudo skin relief, and a means for displaying the simulation result. The invention's effect

 [0011] According to the present invention, a technique for forming a pseudo-skin image having a fractal dimension is provided, and simulation of a pseudo-skin image is performed by changing reflection conditions and undulation height (height ratio). A technique for performing shading can be provided, and further, a technique for distinguishing skin by using the pseudo skin image as a standard image can be provided.

 Brief Description of Drawings

 FIG. 1 is a flowchart showing the overall configuration of a simulation method according to the present invention.

 [Fig.2] A fractal image using fBm (drawing substitute photo)

FIG. 3 is a diagram showing the concept of division in the box counting method. FIG. 5 is a diagram showing a fractal dimension.

 FIG. 6 is a hardware block diagram in the present invention.

 FIG. 7 is a diagram showing a pseudo skin image having a fractal dimension produced by fBm (drawing substitute photo).

 FIG. 8 is a diagram showing a fractal signal image by fBm and a pseudo skin image created by the fBm signal (drawing substitute photograph).

 FIG. 9 is a diagram showing a fractal dimension relationship between an input image by fBm and a pseudo skin image.

Yes

 FIG. 10 is a diagram showing a relationship between a reflection coefficient and a fractal dimension of a pseudo skin image.

 FIG. 11 is a simulation diagram showing the relationship between the fractal dimension of the skin image and the fractal dimension of the skin surface relief.

 FIG. 12 is a diagram showing a pseudo skin image created based on skin data (drawing substitute photograph).

 FIG. 13 is a diagram showing a change in a pseudo skin image due to a reflection coefficient (drawing substitute photograph).

 FIG. 14 is a diagram showing a relationship between a reflection coefficient and a fractal dimension of a pseudo skin image.

 BEST MODE FOR CARRYING OUT THE INVENTION

[0013] The best mode for carrying out the present invention will be specifically described below with reference to the drawings. However, the following configuration is an example, and the present invention is not limited to the configuration of the embodiment.

[1] (1) Implementation process of the present invention

 FIG. 1 is a flowchart showing the overall configuration of a simulation method for forming a pseudo skin image according to the present invention, which is executed by a program using hardware such as a computer. The present invention inputs a fractal dimension value of 2.0 to 3.0 and creates a pseudo skin undulation from a signal of a fractional Brownian motion having the fractal dimension value. The simulation image displayed in step S3 is the simulated skin image in the present invention. The simulation image is composed of step S2 for performing light reflection simulation on the surface and step S3 for displaying the simulation result.

In the simulation S2 process, the simulation is performed by changing the height of the undulations, and in the S2-1 process, the simulation is performed by changing the diffuse reflectance and the specular reflectance (hereinafter also referred to as the reflection coefficient). — May include two steps. [0015] The fractal dimension is a numerical value representing the self-similarity or complexity of a signal or a figure. The larger the value, the more complicated the figure. In the formation of a pseudo skin image, the fractal dimension of the object represented by the function f ( _x , y), such as an image or undulation, takes a value from 2.0 to less than 3.0. This is due to the force S that the plane dimension is 2 and the solid dimension is 3.

 [0016] (2) S 1 step to create pseudo skin relief

In the present invention, a pseudo skin relief is produced in the S1 step. Examples of the method for producing the pseudo skin relief include a method for producing the pseudo skin relief using a fractional brown motion signal. Ij ij ci fraction brownian motion (fBm: fraction Brownian motion; brown) is a random movement of particles with no regularity caused by air particles colliding at various speeds from various directions. In motion, it is defined as a stochastic process that appears as a continuous-time approximation of a long-term memory time series, and it is possible to generate a signal with an arbitrary fractal dimension by using a fractional Brownian motion (hereinafter abbreviated as fBm) such as force. In other words, the power spectral density of an fBm signal with an arbitrary Hurst exponent H (0 <H <1) is p (f) between the Euclidean dimension d where the signal exists and p (f) l / f ^{2H + d} (1), and the relationship between H and the fractal dimension D is D = d + 1—H (2).

 Therefore, the power spectral density and fractal dimension of the fBm signal are

p (f) K 1 / 严^{+ D} - ¹ .

 Here, in order to obtain a skin image having an arbitrary fractal dimension and a skin relief value, the power spectrum w (u, V) of the two-dimensional white noise is converted as follows so as to satisfy Equation (1). To do.

 Country

その結果、逆フーリエ変換することにより Hにより設定されたフラクタル次元を持つ疑 似的な肌起伏を得ることができる。図 2には、 256 * 256[pixels]の画像サイズで作製 した fBm信号に従った 2. 2次元と 2. 8次元のフラクタル次元を持つ疑似的な肌起伏 の画像（以下、入力画像ともいう。）の例を示す。輝度値の範囲は 0〜255に正規化し ている力 2. 2次元と比べ 2. 8次元の画像がより濃淡がより複雑に変化していること が明確である。このように、任意のフラクタル次元を有するフラクショナルブラウン運動 の信号を発生させることにより、疑似的な肌起伏を作製することができる。

As a result, it is possible to have a fractal dimension set by H by inverse Fourier transform. Similar skin relief can be obtained. Figure 2 shows a fake image with a fractal dimension of 2D and 2. 8D (hereinafter also referred to as an input image) according to the fBm signal created with an image size of 256 * 256 [pixels]. .) Example. The range of luminance values is normalized to 0 to 255. 2. Compared to 2D 2. It is clear that the 8D image has more complex shade changes. In this way, by generating a fractional brown motion signal having an arbitrary fractal dimension, a pseudo skin relief can be produced.

 [0017] (3) Light reflection simulation S2 process

 In the present invention, simulation is performed by measuring reflected light by reflecting light artificially on the artificial skin relief surface produced in step S1.

 In the S2 process, which simulates light reflection on the rough skin surface, for example, three-dimensional

Simulation can be performed using the ray tracing method (see Non-Patent Document 1) used for drawing CG and the like.

 The ray-tracing method is a technique for generating a three-dimensional image by back tracking light from the viewpoint to the light source, and can be used for realistic expression by optical simulation.

[0018] (4) Simulating by changing the height of the skin relief on the surface of the pseudo skin relief S2-1—Step 1

 In the present invention, it is possible to include the S2-1 step of performing simulation by changing the height of the skin relief for the pseudo skin relief produced in the S1 step.

 The height of the undulation refers to the ratio of the height of the z axis to the xy plane of the three-dimensional undulation structure. The height of the undulation changes, and the angle of the reflective surface in the ray tracing method changes. To do. This means to what extent unevenness is taken into account for the relief of the three-dimensional structure. When simulating, consider how much of the structure on the skin (for example, the strength of the visible level such as the eyelid pores, the invisible level of the skin groove hill (so-called texture) level)! The set value varies depending on whether the simulation is performed. In other words, when the height ratio is increased, the skin is simulated when assuming pores, and when the height ratio is decreased, simulation is performed when assuming a cuticle skin or a smaller horny layer cell cluster. It becomes an image.

As demonstrated in Example 2 below, by changing the height of the skin relief, A fine and beautiful pseudo skin image can be arbitrarily formed.

[0019] (5) Simulate by changing the reflection coefficient on the surface of the artificial skin relief S2

 2 steps

 The present invention can include a step S2-2 in which the simulation is performed by changing the reflection coefficient for the artificial skin relief produced in the step S1.

 The reflection coefficient consists of two elements: diffuse reflectance and specular reflectance.

 In general, there are both diffuse reflection and specular reflection in the reflection of a three-dimensional structure, and the reflected light is represented by the sum of the reflections. Diffuse reflection is a reflection in which light is scattered in all directions due to very fine irregularities on the surface, whereas specular reflection is a reflection in only one direction. The diffuse reflectance and specular reflectance, which are the respective reflection coefficients, can be calculated by the ratio of the incident light with respect to the normal of the sample surface and the reflected light at the light receiving angle or the reflection angle. By changing the reflection coefficient, the pseudo skin image changes, and the fractal dimension for the pseudo skin image also changes. Figure 10 shows an example of fractal dimension fluctuations in the simulated skin image when the diffuse reflectance and specular reflectance are varied for a fake skin fractal dimension of 2.1. This suggests that the skin looks the most beautiful when the fractal dimension of the pseudo-skin image shows the maximum and maximum values for the reflection coefficient.

[0020] (6) S3 process for displaying simulation results

 In the present invention, simulation results are displayed in step S3.

 The simulation image displayed in step S3 is the pseudo skin image of the present invention. An image in the present invention refers to an image that has been transferred onto a photosensitive material, paper, screen, television, CRT-liquid crystal, etc. by mechanical processing. In the display process, the image is displayed on various display media. I can do it. In addition, fractal dimensions that are pseudo-image information, images of pseudo-skin images that are colored, and images that are displayed in three dimensions can also be used in similar situations.

[0021] The simulation image displayed in step S3 has fractal nature, and the fractal dimension is measured by an arbitrary method. Many methods have been proposed to estimate the fractal dimension of 2D data such as images and undulations. It is desirable to apply the box counting method based on the standard deviation in the space to the skin image and the undulation value of the skin surface.

[0022] The box counting method is to divide a square (cube) that completely covers an object into squares (cubes) of arbitrary size, and to divide the size of the square (cube) and a part of the object. This is a method for obtaining the fractal dimension from the relationship with the number of (cubes), and is generally used to calculate the fractal dimension. When a certain shape is a square (cube) that completely covers the object divided by the length of one side h, the number of squares (cubes) that cover part of the object is N (h), Between r and N (h),

 [Equation 2]

N (h) = c · h " ^D (where c is a constant coefficient) · · · · (2) and if the approximate expression consists of correlations, the object is considered to be a fractal shape, At this time, D in Eq. (2) is the fractal dimension, so in order to obtain the fractal dimension D by the box counting method, logarithm plotting c'h and N (h) is performed. Find the slope of

 [0023] Such a box counting method is very simple and can be processed at high speed by a computer. However, the farther the target fractal dimension is from the half-integer value, the lower the analysis accuracy. Therefore, it is preferable to use a method in which the box size in a general box counting method is determined based on the standard deviation of the property values in the box. In other words, the effective box size is determined based on the standard deviation of the data in the box rather than simply determining whether or not a part of the object falls within the box. It is preferable to use a method that includes the step of determining whether or not is in the box.

 [0024] The calculation of such a fractal dimension can be specifically performed by the following method.

 (i) First, as shown in FIG. 3, the two-dimensional discrete data f (x, y) existing in the size X X Υ is divided into areas S (x, y) of size h * h (m). When using an image signal, the discrete data existing in X XY is a pixel, and when using an undulation value, it is the height data from the reference plane. h can be arbitrarily determined.

 [Ii] (ii) For each of the regions S to S, the standard deviations σ to σ of the property values are expressed by the following equations:

1 m 1 m (See Fig. 4) ₍

[0026] [Equation 3]: 僵 歸

 1: Average of leakage

(Iii) N (h) at size h is calculated by the following equation.

 [Equation 4]

[0028] By calculating N (h) in this way, the number of boxes can be counted using the standard deviation in the region Si of h X h as an effective box size. It becomes possible to suppress the influence of sudden noise. Also, it is indispensable for fractal dimension estimation;! ~ A wide scaling range of nearly 2 digits is obtained.

[0029] (iv) The size h is increased and f (x, _y ) is subdivided, and N is similarly obtained using the procedures (i) to (iii).

 Calculate (h).

 (v) Repeat (iv) until h = X or h = Y, and calculate N (h).

 (vi) The fractal dimension D can be obtained from the slope of the graph representing the relationship between logN (h) and logh (see Fig. 5).

 [0030] (7) Hardware for performing simulation of the present invention

FIG. 6 is a block diagram of hardware that performs simulation in the embodiment of the present invention. The hardware for performing the simulation of the present invention may be a general-purpose computer such as a personal computer, or may be a computer device dedicated to simulation. The input unit 1 is a means for inputting an arbitrary fractal dimension value, inputting an fBm signal, inputting a reflection coefficient for a pseudo skin image, inputting a height of skin relief, for example, an input device such as a keyboard. I can do it. CPU2 (Central Processing Unit) is a means for executing the simulation program of this embodiment and calculating the fractal dimension of the simulation image. RAM3 (Random Access Memory) is a storage means for storing programs to be executed by CPU2 and temporary data. The display unit 4 is a means for outputting a processing result obtained by executing the simulation program. For example, the display unit 4 can be a display device such as a liquid crystal display or an output device such as a printer.

 [0031] (8) Pseudo-skin image formed by the present invention

 The pseudo skin image having a fractal dimension formed according to the present invention is used as a standard image when comparing with a human skin image or when identifying a fractal dimension in actual skin or skin coated with cosmetics. be able to. The standard image in the present invention refers to an image serving as a reference when distinguishing the actual fractal dimension of the skin. In addition, a plurality of pseudo skin images having different fractal dimensions can be arranged as standard images, and a panel can be produced in which fractal dimension values of the standard images are arranged at regular intervals. The fractal dimension of the standard image when the above panel is manufactured may be arranged in increments of 0.1, may be arranged in increments of 0.2, or may be arranged in increments of 0.5. It is possible to produce a panel that arranges standard images in increments of approximately 0 · 01 -0.

 In addition, the panel as used in this application means the drawing board 'bed plate which has arrange | positioned the several pseudo skin image, and a material is not ask | required. An image in which a plurality of pseudo skin images are arranged on a computer is also included in the panel in the present application.

 [0032] Using the pseudo-skin image of the present invention, a plurality of pseudo-skin images having different fractal dimensions are used as standard images, and the actual skin image obtained from the subject's skin is compared with the standard image, and the actual skin is compared. A standard image approximating the image can be selected and the fractal dimension of the standard image can be identified as the actual skin fractal dimension.

 In this discrimination, skin can be more accurately discriminated by arranging the fractal dimension values of the standard image at regular intervals! /, And having a panel panel! /.

The fractal dimension of the pseudo-skin image is based on the fractal dimension of the actual skin geometry. This distinction method is possible because it is characterized by the fact that the dimensional relationship is preserved. This is demonstrated in Example 4 described later. The larger the fractal dimension of the pseudo skin image, the larger the fractal dimension of the actual skin geometric structure.

 In addition, the pseudo-skin image of the present invention can be used for IJ for multifaceted and convenient purposes as skin counseling and skin image evaluation training, or as a display medium, printed matter or CRT display in sales.

 [0033] In the present invention, a dull produced using at least two values of the fractal dimension value of the pseudo skin image and the diffuse reflectance value and specular reflectance value of light set in step S2-2. It is also possible to make a matrix or a matrix.

 By displaying the skin fractal characteristics with respect to the reflection coefficient as a graph having at least two axes of the reflection coefficient axis of the diffuse reflectance and the specular reflectance and the fractal dimension axis of the reflection surface as shown in FIG. It is possible to easily produce a pseudo skin image having a required fractal dimension or a pseudo skin image by selecting an appropriate reflection coefficient. The fractal characteristic of the skin in the present invention refers to a characteristic in which the fractal dimension of the pseudo skin image is changed by changing the fractal dimension, reflection coefficient, or the like of the input image.

 Furthermore, as shown in FIG. 13 of Example 5 to be described later, the panel is formed by arranging a plurality of pseudo skin images formed according to the present invention, a plurality of pseudo skin images having different fractal dimensions are arranged, and the pseudo skin images are arranged. It is possible to produce a panel having the fractal dimension of the skin image as one axis and the light reflection coefficient value set in the S2-2 step as the other axis. By preparing this panel, you can use it for the counseling of skin.

 [0034] Further, it is characterized in that the fractal dimension of the skin before and after the cosmetic application is measured, and the change in the fractal dimension is larger, and the cosmetic effect of the cosmetic is differentiated. It is also possible to perform a method for distinguishing makeup effects.

For example, measure the fractal dimension of the skin before applying the cosmetic, measure the fractal dimension of the skin again after using cosmetics such as lotion for a certain period of time, and the change in the fractal dimension is larger. It can be distinguished from the cosmetic effect of cosmetics such as water. This is possible because the fractal dimension and skin beauty have a positive correlation. (9) Program used in the present invention

 The program used in the present invention is a simulation program. A computer inputs a fractal dimension value of 2.0 to 3.0, and creates a pseudo skin relief by a signal of a fractional brown motion having the fractal dimension value. Means for performing simulation of light reflection on the surface of the artificial skin relief, means for displaying the simulation result,

2. By inputting a fractal dimension value of 0 to 3 · 0 and creating a pseudo skin relief by using a signal of the fractional brown motion having the fractal dimension value, an arbitrary fractal dimension value is input to A signal is generated, and an inverse Fourier transform is performed to generate a pseudo skin relief.

 In the means for simulating light reflection on the surface of the pseudo skin relief, the reflection coefficient for the surface of the pseudo skin relief and the height of the skin relief are set as necessary. The ray tracing method (see Non-Patent Document 1) used to depict 3D CG, etc. applies parallel rays from the sky to the artificial skin relief, and the height from the relief is constant. A simulated skin image is created by setting a reflective surface at the position and measuring the reflected light. The fractal dimension of the simulation image is calculated.

 The means for displaying the simulation result can also display the fractal dimension calculated simultaneously with the force for displaying the pseudo skin image on the display unit 4. Note that the calculation process of the fractal dimension of the simulation image is performed by the CPU 2 described above.

 FIG. 8 is an example of the pseudo skin image obtained in this way. As a result of measurement by the above box counting method performed by CPU2, the fractal dimensions are 2.62 and 2.78, respectively, indicating a clear difference in unevenness. It can be seen that the 2.78 image, which has a larger fractal dimension, shows more complex changes and has a more beautiful simulated skin feel. The correlation between the flatter dimension and the beauty of the skin is also shown in the estimation method of the visual evaluation value of the beauty of the skin (Japanese Patent Application No. 20 06-046659).

 Example

[0036] Hereinafter, the present invention will be described in detail by way of examples, but the scope of the present invention is not limited thereby. <Example 1>

 From the above simulation program, enter the fractor dimension as 2.14, 2.33 and 2.53 to create a fake skin image by fBm signal, and then apply the fuzzy surface to the surface of the fake skin relief. Was set to 1: 1, and parallel rays were reflected by the ray tracing method to obtain a pseudo skin image (see Fig. 8). From FIG. 8, the obtained pseudo skin image was a pseudo skin image having a fractal dimension of 2.64, 2.72 and 2.73, respectively, by the box counting method.

 <Example 2>

 In Example 1, the angle of the reflecting surface is set by setting the height of the skin relief to 1: 1, 1: 1/2, 1: 1/4, and 1: 1/8 with respect to the surface of the pseudo skin relief. The pseudo skin image by reflection of parallel rays was obtained by ray tracing method (see Fig. 9). This shows that the fractal dimension of the reflected image increases as the fractal dimension of the three-dimensional relief structure increases. If the reflective surface is set gently (decreasing the height relative to the plane), the reflected image It can be seen that the fractal dimension is not easily saturated. Therefore, it can be seen that a finer and more beautiful pseudo-skin image can be arbitrarily created by varying the height ratio of the pseudo skin relief.

 <Example 3>

 In Example 2, the nine pseudo-skin images obtained by setting the height of the skin relief to 1: 1/8 with respect to the surface of the pseudo skin relief, Female subjects were selected to evaluate the beauty of these nine pseudo-skin images. The six skins were arranged in order from 1 to 9 in the order they thought they were beautiful, and a regression analysis was performed on the average rank (y) of the six people and the fructa nore dimension (X) of the skins. The obtained regression equation was y = —42.36x + 119.99, Spearman correlation coefficient was 0.954, and both showed high correlation. This indicates that the fractal dimension of the suspicious skin image and the visual evaluation value of the beauty of the skin have a positive correlation, and the suspicion of any beauty (having an arbitrary fractal dimension) using the correlation is shown. It turns out that a similar skin image can be produced.

 <Example 4>

Next, in order to clarify the relationship between the skin image and the skin surface relief, a simulation is performed. It was. After preparing skin replica specimens from 240 female subjects aged 19-55 years using Asahi Biomed's silicone replica agent, using a 3D image processor from Science Systems Co., Ltd. 3 Dimensional shape data was obtained. Calculating the height is 260. 5 m undulations of the actual skin is the average of your Keru 240 people in the z-axis of the three-dimensional shape data, _z for the xy plane undulations of the three-dimensional structure on the basis of this value Set the axis height to 1: 1 / 37.6, and apply parallel rays by ray's tracing method to fake undulations of fractal dimension 2 · 10 ~ 2 · 40 from skin replica specimen, The simulation image (see Fig. 12) and the fractal dimension of the simulation image were obtained (see Fig. 10).

 [0041] Fig. 10 is a simulation showing the relationship between the fractal dimension of the three-dimensional relief structure obtained from the skin replica specimen and the fractal dimension of the simulation image. It is suggested that the fractal dimension also improves and looks beautiful. In addition, the fractal dimension of the buttock of 240 people actually analyzed is 2.60-2.75, which is consistent with the simulation results. By utilizing this, for example, when the fractal dimension of the skin surface relief cannot be measured by applying makeup, the fractal dimension of the skin made up from the image obtained with a digital camera etc. The ability to fi

 [0042] FIG. 12 is an example of a pseudo skin image close to actual skin created based on skin data with the diffuse reflectance set to 0.6 and the specular reflectance set to 0.1. It can be seen that this simulation image power, the lala-flatal dimension is large, and the visual beauty is better!

 <Example 5>

 A simulation was conducted to clarify the interrelationships between the simulated skin relief, reflection coefficient, and simulation image. Pseudo undulation is a fractal dimension based on fBm 2. 1 5 to 2.48, 7 levels, reflection coefficient is diffuse reflectance and specular reflectance from 0.0 to 1.0; 6 levels up to 1.0, undulation height Was set to 1: 1/4, and the fractal dimension dependence of the reflecting surface due to diffuse reflectance and specular reflectance was examined (see Fig. 14), and a pseudo skin image was obtained (see Fig. 13).

[0044] Fig. 13 shows the fractal dimension of the pseudo skin undulation varying from 2.5 to 2.48, the diffuse reflectance from 0.0 to 0.8, and the specular reflectance from 1.0 to 0.2. Nine simulated skin images are shown. Pseudo-skin image changes greatly depending on the reflection coefficient, and how the skin looks depending on how light strikes Is suggested to change. For example, the pseudo-skin image in the lower left of Fig. 13 (pseudo-undulation fractal dimension 2.48, specular reflectance 1.0) has a fractal dimension of 2.85, indicating that it looks the most beautiful.

FIG. 14 is a simulation showing the relationship between the fractal dimension of the three-dimensional relief structure and the fractal dimension of the pseudo-skin image accompanying the change in the reflection coefficient. When the fractal dimension of the three-dimensional relief structure is up to 2.20, the fractal dimension of the pseudo-skin image takes a maximum value when the diffuse reflectance is 0.2 and the specular reflectance is 0.8, but the fractal dimension of the three-dimensional relief structure is 2. It can be seen that the fractal dimension of the pseudo-skin image takes the maximum value at 30 or more when the diffuse reflectance is 0.0 and the specular reflectance is 1.0. This suggests that the appearance and beauty of the skin can be changed by considering how the light strikes according to the skin condition (fractal dimension of the three-dimensional relief structure). It can be used for skin counseling, care, stage and TV makeup.

 Industrial applicability

According to the present invention, a pseudo skin image having an arbitrary fractal dimension, that is, a pseudo skin image having an arbitrary beauty can be produced. In addition, the skin condition can be changed by the way the light strikes (reflection coefficient), that is, the artificial skin image by the reflection coefficient of the skin surface and the fractal dimension simulation technology can be provided. Providing proper information on skin counseling and care methods at training or sales sites!

Claims

The scope of the claims [1] A method of forming a pseudo skin image,  2. S1 step of selecting a fractal dimension value of 0 to 3.0 and creating a pseudo skin undulation by a signal of a fractional brown motion having the fractal dimension value;  S2 process for performing light reflection simulation on the surface of the artificial skin relief,  S3 process for displaying the simulation result,  A method for forming a pseudo skin image. [2] The image forming method according to claim 1, wherein the step S2 includes a step S2-1 in which simulation is performed by changing a height of the skin relief on the surface of the pseudo skin relief. [3] The image formation according to claim 1 or 2, wherein the step S2 includes a step S2-2 in which simulation is performed by changing the diffuse reflectance and specular reflectance of light with respect to the surface of the pseudo undulation. Method. [4] A pseudo skin image formed by the method according to any one of claims 1 to 3. [5] At least two values of the fractal dimension value of the pseudo-skin image formed by the method of claim 3 and the diffuse reflectance value and specular reflectance value of light set in step S2-2. A graph or matrix produced by using. [6] A method for distinguishing skin using the pseudo-skin image according to claim 4,  A plurality of pseudo skin images with different fractal dimensions are used as standard images.  Compare the actual skin image obtained from the subject's skin with the standard image,  Select a standard image that approximates the actual skin image,  A method for distinguishing skin, characterized in that the fractal dimension of the standard image is differentiated from the actual skin fractal dimension. [7] A simulation program for forming a simulation image of skin by a programmed computer.  2. Means for inputting a fractal dimension value of 0 to 3 · 0 and generating a pseudo skin undulation by a signal of a fractional brown motion having the fractal dimension value,  Means for simulating light reflection on the surface of the artificial skin relief, Means for displaying the simulation results; Simulation program to function as