Image processing apparatus, image processing method, and image processing program

Abstract

To provide an image processing device, an image processing method, and an image processing program capable of generating an image in consideration of a light beam state to an object.SOLUTION: An image processing device (100) includes a shape information analyzing unit (14) that calculates a geometric shape including a normal distribution on a face of an object, a basic ray setting unit (18A) that sets a radiation position of a basic ray related to rendering of the object, a supplementary ray setting unit (18B) that sets a radiation position of a supplementary ray having a different radiation position from the basic ray, and a display image generating unit (22) that controls radiation brightness of the basic ray by a weight calculated based on a basic ray normal line vector obtained by radiation of the basic ray and a supplementary ray normal line vector obtained by radiation of the supplementary ray and generates an image in which a fine shape of the face of the object is emphasized based on the geometric shape of the face of the object.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an image processing device, an image processing method, and an image processing program. [Background technology]

[0002] In recent years, the use of machining simulators, which simulate the shape and surface texture of the machining result based on the parameters set on the machining machine before machining, has been increasing. However, machining using NC (numerical control) machining programs such as G-code created by CAM (computer-aided manufacturing) systems can sometimes result in machining defects that result in a finished product that differs from the intentions of the machining designer. Machining defects can occur, for example, when there is a problem with the prepared machining program itself, or when the machining conditions or adjustments to the machine tool are inappropriate and the machine tool does not follow the instructions of the machining program. In the case of cutting, particularly when there is a problem with the machining program, machining defects often manifest as uncut material or over-cutting.

[0003] Typically, a set of NC machining instructions is tested by machining a test workpiece formed from a softer, less expensive material before machining the desired part. If visual inspection of the test workpiece reveals undesirable discrepancies in the test workpiece from the desired shape, the NC machining instructions can be modified. However, such manual testing is time-consuming and costly. For example, the time to machine a single test workpiece may require several hours, and several iterations may be required before an acceptable set of NC machining instructions is obtained. Therefore, it is desirable to test the test workpiece for discrepancies from the desired shape through computer-based simulations and renderings.

[0004] However, when rendering metals that contain fine surface features, the metal's reflections can be too directional, resulting in blown-out highlights, or the use of an inappropriate environment map can cause the metal surface to reflect off, making the fine surface features less visible.

[0005] Patent document 1 discloses an invention of an image processing device, an image processing method, and a program that calculates the angle between the normal of each polygon of the surface shape that makes up an object and a light vector, and increases the brightness of the texture the closer it is to 0 degrees (i.e., the closer the angle), thereby making it easier to see the facial expressions of characters placed in a virtual space. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-140237 Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the invention described in Patent Document 1, since characters have a front, the character can be displayed with good visibility by determining the angle of the light vector with respect to a specific normal direction and determining the texture brightness, but the machined surface does not have a front, so the machined surface characteristics cannot be displayed with good visibility unless the lighting parameters are optimized based on the characteristics of the machined surface.In addition, since metal has high directional reflection, there is a problem that the machined workpiece cannot be displayed with good visibility if inappropriate lighting parameters or environment maps are used.

[0008] An object of the present disclosure is to provide an image processing device, an image processing method, and an image processing program that are capable of generating an image taking into account the state of light rays on an object. [Means for solving the problem]

[0009] The image processing device of the present disclosure includes a shape information analysis unit that calculates the geometric shape of the surface of the object including the normal distribution on the surface of the object; a basic ray setting unit that sets the irradiation position of a basic ray related to rendering of the object on the object; an auxiliary ray setting unit that sets the irradiation position of an auxiliary ray, which has an irradiation position on the object different from that of the basic ray, in conjunction with the viewpoint position of a virtual camera; and a display image generation unit that controls the irradiation brightness of the basic ray using weights calculated based on the basic ray normal vector obtained by irradiating the basic ray and the auxiliary ray normal vector obtained by irradiating the auxiliary ray, and generates an image that emphasizes the fine shape of the surface of the object based on the geometric shape of the surface of the object including the normal distribution on the surface of the object.

[0010] The image processing method of the present disclosure is an image processing method executed by a computer, and includes the steps of: calculating the geometric shape of the surface of the object including the normal distribution on the surface of the object; setting the irradiation position of a basic ray related to rendering of the object on the object; setting the irradiation positions of auxiliary ray beams, which have irradiation positions on the object different from those of the basic ray, in conjunction with the viewpoint position of a virtual camera; controlling the irradiation brightness of the basic ray beam using weights calculated based on the basic ray normal vector obtained by irradiating the basic ray and the auxiliary ray normal vector obtained by irradiating the auxiliary ray, and generating an image that emphasizes the fine shape of the surface of the object based on the geometric shape of the surface of the object including the normal distribution on the surface of the object.

[0011] The image processing program of the present disclosure causes a computer to execute the steps of: calculating the geometric shape of the surface of the object, including the normal distribution on the surface of the object; setting the irradiation position of a basic ray related to rendering of the object on the object; setting the irradiation positions of auxiliary ray beams, which have irradiation positions on the object different from those of the basic ray, in conjunction with the viewpoint position of a virtual camera; controlling the irradiation brightness of the basic ray beam using weights calculated based on the basic ray normal vector obtained by irradiating the basic ray and the auxiliary ray normal vector obtained by irradiating the auxiliary ray, and generating an image that emphasizes the fine shape of the surface of the object based on the geometric shape of the surface of the object, including the normal distribution on the surface of the object. [Effects of the Invention]

[0012] According to the present disclosure, it is possible to provide an image processing device, an image processing method, and an image processing program that are capable of generating an image taking into account the state of light rays on an object. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic diagram showing an example of a configuration of an image processing device according to an embodiment of the present invention. [Figure 2] 1 is a block diagram illustrating a schematic configuration of a machining system that machines a workpiece related to a display image generated by an image processing device according to the present embodiment. [Figure 3] FIG. 2 is a block diagram showing an example of a hardware configuration of a control unit according to the present embodiment. [Figure 4] FIG. 10 is an explanatory diagram showing an example of the geometric relationship between an object shape, a basic ray, an auxiliary ray, and a camera. [Figure 5]10A and 10B are schematic diagrams showing the configuration of auxiliary rays relative to a basic ray. (A) shows four auxiliary rays, two in each of the x-axis and y-axis directions centered on the basic ray; (B) shows two auxiliary rays in the x-axis direction centered on the basic ray; (C) shows two auxiliary rays in the y-axis direction centered on the basic ray; and (D) shows one auxiliary ray adjacent to the basic ray. [Figure 6] 10 is a flowchart showing an example of processing by the image processing device according to the present embodiment. [Figure 7] FIG. 1A is a schematic diagram showing an example of a conventional rendering result without using auxiliary rays, and FIG. 1B is a schematic diagram showing an example of a rendering result with the use of auxiliary rays according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] An image processing device, an image processing method, and an image processing program according to embodiments will be described below with reference to the drawings. The following embodiments are merely examples, and the embodiments can be appropriately combined and modified.

[0015] Fig. 1 is a schematic diagram showing an example of the configuration of an image processing device 100 according to this embodiment. As shown in Fig. 1, the image processing device 100 includes a shape data input unit 12 to which shape data of an object, i.e., shape data of a workpiece processed by a machine tool, is input, a control unit 10 that generates three-dimensional CG (Computer Graphics) by rendering the shape data received from the shape data input unit 12, and a display unit 24 that displays the generated three-dimensional CG.

[0016] Information indicating the shape of the workpiece surface and information such as the workpiece surface texture are input to the shape data input unit 12. Information indicating the shape of the workpiece surface is, for example, two-dimensional or three-dimensional CAD (Computer-Aided Design) data, coordinate values ​​of the surfaces that make up the workpiece, or G-code, which is an NC machining command output by a CAM device (described later). Information on the workpiece surface texture is, for example, information on the workpiece surface material and surface treatment. More specifically, information on the workpiece surface material is information indicating aluminum, iron, copper, stainless steel, chromium, titanium, synthetic resin, or the like. Furthermore, information on the surface treatment is, more specifically, information indicating a mirror finish, hairline, matte finish, or the like.

[0017] The control unit 10 includes a shape information analysis unit 14 that analyzes information indicating the surface shape of the workpiece input to the shape data input unit 12; a material information setting unit 16 that sets the material of the workpiece based on information related to the surface texture of the workpiece input to the shape data input unit 12; a lighting condition setting unit 18 that sets the lighting conditions for the workpiece; a virtual camera setting unit 20 that sets the position of a virtual camera (hereinafter referred to as a "virtual camera"), assuming that the 3D CG of the workpiece is an image captured by the virtual camera; and a display image generation unit 22 that generates the 3D CG of the workpiece based on the material of the workpiece set by the material information setting unit 16, the lighting conditions set by the lighting condition setting unit 18, and the position of the virtual camera set by the virtual camera setting unit 20.

[0018] The display image generation unit 22 outputs the generated 3D CG to the display unit 24. The display unit 24 is, for example, a monitor such as a liquid crystal display, an organic EL (Electro Luminescence) display, a micro LED (Light Emitting Diode) display, or a CRT (Cathode Ray Tube). The display unit 24 may also be an aerial display, an HMD (Head Mounted Display), a VR (Virtual Reality) device, an AR (Augmented Reality) device, a tablet terminal, a smartphone, a television, or the like.

[0019] The shape information analysis unit 14 calculates the normal distribution function for a part or all of the area of ​​the workpiece, for example, based on the shape information of the workpiece surface. For example, the Microfacet model assumes that the complex reflection patterns on the workpiece surface are caused by the distribution of minute normals on the workpiece surface. The normal distribution function is a probability distribution function that indicates the existence of such normal vectors. In this embodiment, the roughness of the workpiece surface is determined by sampling the distribution of normal vectors, which is the calculation result of the normal distribution function. A distribution function called the Beckmann distribution shown in the following equation (1) is often used as the normal distribution function. In the following equation (1), m is the average slope of the minute facets on the object surface, and α is the angle between the normal vector of the minute facets on the object surface and the intermediate vector obtained by adding the vector from the object surface to the light source and the vector from the object surface to the line of sight (virtual camera direction).

[0020]

number

[0021] In this embodiment, for example, if the value calculated by the above formula (1) is less than 0.1, it is determined that the surface is smooth, and if it is 0.1 or more, it is determined that the surface is rough. In addition to the Beckmann distribution shown in formula (1), a distribution function such as GGX (Trowbridge-Retiz) may also be used.

[0022] The lighting condition setting unit 18 sets the lighting radiation position and angle, as well as the lighting radiation intensity, in conjunction with the coordinate position and line of sight direction of the virtual camera, based on the calculation result of the normal distribution function by the shape information analysis unit 14. The lighting condition setting unit 18 includes a basic light ray setting unit 18A that sets basic light rays emitted from a virtually provided main light source onto the workpiece, and an auxiliary light ray setting unit 18B that sets auxiliary light rays that are supplementary lighting other than the basic light rays.

[0023] The basic light ray setting unit 18A sets the position, intensity, direction, and light distribution of the lighting that illuminates the displayed workpiece, as well as an environmental map of the area around the workpiece. For example, the basic light ray setting unit 18A sets the illumination range of the lighting and sets the ray position of the basic light ray in conjunction with the viewpoint position of the virtual camera. Specifically, the basic light ray setting unit 18A sets the basic light ray to be emitted to the workpiece from the same position as the coordinates of the virtual camera, and further sets the position of the basic light ray to move in conjunction with the movement of the coordinate position of the virtual camera as it moves in virtual space.

[0024] The fill ray setting unit 18B sets the fill ray so that it illuminates a position slightly shifted from the coordinates of the workpiece illuminated by the basic ray. The fill ray is irradiated by shifting it by a sub-pixel of one pixel or less from the coordinates of the object illuminated by the basic ray, for example. Multiple fill ray may be set for one basic ray. The shift amount of the fill ray from the basic ray may be determined depending on the fineness of the surface shape of the object (workpiece) calculated by the shape information analysis unit 14.

[0025] The virtual camera setting unit 20 sets the position of the virtual camera by setting the viewpoint position, line of sight direction, and field of view for observing the displayed workpiece.

[0026] The display image generation unit 22 generates a display image by performing rendering based on the information input from the shape data input unit 12, as well as the information set by the virtual camera setting unit 20, the material information setting unit 16, the base ray setting unit 18A in the lighting condition setting unit 18, and the fill ray setting unit 18B in the lighting condition setting unit 18. The display image generation unit 22 performs rendering using, for example, a path tracing method based on base rays. Specifically, the display image generation unit 22 generates a realistic display image (3D CG) by calculating the appearance based on repeated reflections of base rays on the work surface. The display image generation unit 22 outputs the generated display image to the display unit 24, and the display unit 24 displays the display image.

[0027] 2 is a block diagram showing a schematic configuration of a machining system 1 that machines a workpiece related to a display image generated by an image processing device 100 according to this embodiment. As shown in FIG. 1, the machining system 1 includes a machining simulation device 400, a CAM device 200, and an NC machine tool 300.

[0028] The CAM device 200 creates a machining program such as a G-code in which operation commands to the NC machine tool 300 are written.

[0029] The machining simulation device 400 is a device that simulates, based on three-dimensional CG, the machining of a workpiece by an NC machine tool 300, on the basis of a machining program generated by the CAM device 200. In this embodiment, the image processing device 100 may be included in the machining simulation device 400.

[0030] NC machine tool 300 machines a workpiece based on a machining program created by CAM device 200. In the example shown in FIG. 2, NC machine tool 300 has a ball-end milling cutter 301 as a cutting tool and a drive unit 302 that drives ball-end milling cutter 301. Ball-end milling cutter 301 is capable of forming the surface of the workpiece into a free shape. Drive unit 302 has, for example, a motor and a transmission mechanism (e.g., gears) that transmits the driving force of the motor to ball-end milling cutter 301. Note that NC machine tool 300 is not limited to a ball-end milling cutter and may have other tools such as a drill.

[0031] Fig. 3 is a block diagram showing an example of the hardware configuration of the control unit 10 according to the present embodiment. As shown in Fig. 3, the control unit 10 is configured by a computer in which a CPU (Central Processing Unit) 31, which is a computing element (processor), a main memory 32, an input / output interface (I / O interface) 33, and a memory unit 34 are each connected to a system bus 35. The control unit 10 may be configured by a plurality of computers connected via a network, or may be configured by a processing circuit.

[0032] The CPU 31 is an integrated circuit (IC) that performs arithmetic processing. Other computing elements, such as a digital signal processor (DSP), a graphics processing unit (GPU), a network processor, or a field programmable gate array (FPGA), may be used. By executing the image processing program according to this embodiment, the CPU 31 functions as a shape information analysis unit that analyzes information indicating the surface shape of the workpiece input to the shape data input unit 12, a material information setting unit that sets the material of the workpiece based on information regarding the texture of the surface of the workpiece input to the shape data input unit 12, an illumination condition setting unit that sets the illumination conditions for the workpiece, a virtual camera setting unit that sets the position of a virtual camera, and a display image generation unit that generates a 3D CG image of the workpiece based on the material, illumination conditions, and position of the virtual camera. As a result, by executing the image processing program, the CPU 31 functions as a shape information analysis unit 14, a material information setting unit 16, an illumination condition setting unit 18, a virtual camera setting unit 20, and a display image generation unit 22. The image processing program may be provided, for example, on a recording medium on which these functions are recorded.

[0033] The main memory 32 is configured by a volatile storage device such as a RAM (Random Access Memory) or a non-volatile storage device such as a ROM (Read Only Memory). The storage unit 34 is configured by a non-volatile storage device such as an HDD (Hard Disk Drive) or a flash memory.

[0034] The I / O interface 33 is a port to which the shape data input unit 12, the display unit 24, etc. are connected.

[0035] 4 is an explanatory diagram showing an example of the geometric relationship between the object shape, the base ray, the auxiliary ray, and the camera. As shown in FIG. 4, the base ray 46 emitted from the light source provided on the same axis as the optical axis of the virtual camera 40 is irradiated onto the work surface 53, which is the object shape, and the base ray normal vector nbase In addition, the auxiliary ray 48 is emitted by shifting it by a sub-pixel of one pixel or less from the coordinates of the object illuminated by the basic ray 46, and is projected onto the work surface 53 at a position different from the basic ray 46 in the ray reach range 51. As a result, the auxiliary ray normal vector n auxiliary is obtained. As an example, the auxiliary light rays 48 are emitted within a range of one pixel angle 44 centered on the basic light ray 46 on the imaging plane 42 assumed to exist on the workpiece surface 53. Furthermore, multiple auxiliary light rays 48 may be set for one basic light ray 46. The reach range 51 of the light rays is a predetermined range centered on the basic light ray 46, and is set, for example, to be larger than a range within one pixel from the coordinates of the object illuminated by the basic light ray 46.

[0036] Figure 5 is a schematic diagram showing the configuration of auxiliary rays relative to the basic ray. (A) shows four auxiliary rays, two in each of the x-axis and y-axis directions centered on the basic ray; (B) shows two auxiliary rays in the x-axis direction centered on the basic ray; (C) shows two auxiliary rays in the y-axis direction centered on the basic ray; and (D) shows one auxiliary ray adjacent to the basic ray.

[0037] 5A, the offset 60 between the base ray and the auxiliary ray is a sub-pixel of one pixel or less. The extent of the offset 60 may be determined depending on the fineness of the surface shape of the object calculated based on the normal distribution function.

[0038] In this embodiment, if it is desired to emphasize the surface shape in the horizontal direction (x-axis direction), the auxiliary light beams may be arranged to the left and right of the basic light beam as shown in Fig. 5(B), and if it is desired to emphasize the surface shape in the vertical direction (y-axis direction), the auxiliary light beams may be arranged above and below the basic light beam as shown in Fig. 5(C). Also, as shown in Fig. 5(D), there may be only one auxiliary light beam for the basic light beam, and the auxiliary light beams within the irradiation range may be emitted at random or arbitrary positions relative to the basic light beam.

[0039] As described above with reference to FIG. 4, the base ray 46 generates the base ray normal vector nbase However, auxiliary ray 48 causes auxiliary ray normal vector n auxiliary In this embodiment, the base ray normal vector n base The x, y, and z components of the auxiliary ray normal vector n auxiliary The difference between the x, y, and z components of n is calculated using the following formula (2).

[0040]

number

[0041] Next, as shown in the following equation (3), Δ n Calculate the absolute value of each of the x, y, and z components of

[0042]

number

[0043] Furthermore, when k auxiliary rays are emitted for one basic ray, Δ n Calculate the average of the absolute values ​​of the x, y, and z components of

[0044]

number

[0045] In this embodiment, when calculating the brightness for the basic ray, the auxiliary ray normal vector n auxiliary The magnitude of the change in the normal is used as a weight. The basic ray performs rendering using, for example, path tracing, and calculates the appearance based on repeated reflections to generate a realistic image. The secondary ray traces the light from the origin to the object surface, and calculates the variation of the normal on the object surface.

[0046] The weight weight used to calculate the brightness of the base ray is calculated by the following equation (5). In this embodiment, the base ray normal vector n base and auxiliary ray normal vector n detected by at least one auxiliary ray emitted from a position shifted by less than one pixel from the basic ray. auxiliary The square root of the sum of the average squares of the absolute values ​​of the differences between each of the x, y, and z components is used as the weight.

[0047]

number

[0048] The radiance of the base ray, L, is the original radiance of the base ray, L base is calculated by multiplying the weight calculated by the above equation (5) by a scale factor S, which is a correction coefficient, as shown in the following equation (6). The scale factor S is specifically determined by evaluating a display image obtained by rendering with radiance L, for example.

[0049]

number

[0050] 6 is a flowchart showing an example of processing by the image processing device 100 according to this embodiment. In step S001, shape data is input to the shape data input unit 12, and the image processing device 100 acquires the shape data.

[0051] In step S002, the shape information analysis unit 14 of the control unit 10 calculates normal distribution information of the shape data.

[0052] In step S003, the virtual camera setting unit 20 of the control unit 10 sets camera parameters such as the position, field of view, and sensor size of the virtual camera.

[0053] In step S004, the irradiation position of the basic ray is set to the same position as the viewpoint position of the virtual camera by the basic ray setting unit 18A of the illumination condition setting unit 18 of the control unit 10. The light constituting the basic ray is assumed to randomly irradiate the surface of the object.

[0054] In step S005, the auxiliary ray setting unit 18B of the illumination condition setting unit 18 of the control unit 10 sets the irradiation position and the number of irradiations of the auxiliary ray according to the position of the basic ray.

[0055] In step S006, the material of the shape information is set in the material information setting unit 16 of the control unit 10. The material to be set is, for example, aluminum, iron, copper, stainless steel, chromium, titanium, synthetic resin, or the like.

[0056] In step S007, the display image generation unit 22 of the control unit 10 performs rendering based on the information set by the shape data input unit 12, the virtual camera setting unit 20, the material information setting unit 16, the base ray setting unit 18A in the illumination condition setting unit 18, and the fill ray setting unit 18B in the illumination condition setting unit 18. The rendering tracks changes in optical properties due to reflection for the base ray, as in the path tracing rendering method, but tracks the fill ray from the illumination origin to its arrival at the object surface, and calculates the weight (weight) of the illumination brightness of the base ray by calculating the above-mentioned equations (2) to (5) based on the variation in normal. Then, as shown in the above-mentioned equation (6), the calculated weight (weight) is multiplied by the illumination brightness calculated for the base ray to generate a rendered image. In step S007, by acquiring a geometric shape (e.g., the average slope m of the minute surfaces on the object surface) including the normal distribution near a point of interest in the screen space (e.g., the irradiation position of the basic ray on the surface of the object), the display image generation unit 22 generates an image that emphasizes the fine shape (unevenness) of the surface, and also appropriately controls the irradiation brightness of the basic ray related to rendering to suppress blown-out highlights in the image.

[0057] In step S008, the image generated by the display image generating unit 22 of the control unit 10 is displayed on the display unit 24, and the process ends.

[0058] FIG. 7(A) is a schematic diagram showing an example of a conventional rendering result without using auxiliary rays, and FIG. 7(B) is a schematic diagram showing an example of a rendering result with the use of auxiliary rays according to this embodiment.

[0059] In FIG. 7A, the control of the irradiation intensity of the basic light ray is inappropriate, and the bright part 50 becomes so-called overexposed, making it difficult to confirm the details of the object.

[0060] In FIG. 7B, by controlling the irradiation intensity of the basic light beam using the weight weight calculated based on the irradiation of the auxiliary light beam onto the object, blown-out highlights in the bright part 52 are suppressed, and the details of the object can be confirmed.

[0061] As described above, according to this embodiment, by acquiring a geometric shape including a normal near a point of interest in screen space, the display image generation unit 22 generates an image that emphasizes the fine surface shape, and also appropriately controls the illumination brightness of the basic light rays involved in rendering to suppress overexposure, etc. As a result, it becomes possible to generate an image that takes into account the lighting conditions on the object.

[0062] Furthermore, because auxiliary rays do not perform calculations to track repeated reflections as in rendering using basic rays, even when auxiliary rays are used, the amount of calculation required for the entire process is expected to be less than when auxiliary rays are not used. [Explanation of symbols]

[0063] 10 control unit, 12 shape data input unit, 14 shape information analysis unit, 16 material information setting unit, 18 lighting condition setting unit, 18A basic light ray setting unit, 18B auxiliary light ray setting unit, 20 virtual camera setting unit, 22 display image generation unit, 24 display unit, 31 CPU, 32 main memory, 33 I / O interface, 34 memory unit, 46 basic light ray, 48 auxiliary light ray, 53 work surface, 100 image processing device.

Claims

1. a shape information analysis unit that calculates a geometric shape of a surface of the object, including a normal distribution on the surface of the object; a basic ray setting unit that sets an irradiation position of a basic ray on the object for rendering the object; an auxiliary ray setting unit that sets the irradiation position of an auxiliary ray, which is different from the irradiation position of the basic ray on the object, in conjunction with the viewpoint position of a virtual camera; a display image generation unit that controls the illumination brightness of the basic light beam using a weight calculated based on a basic light ray normal vector obtained by irradiating the basic light beam and an auxiliary light ray normal vector obtained by irradiating the auxiliary light beam, and that generates an image that emphasizes the fine shape of the surface of the object based on the geometric shape of the surface of the object including the normal distribution on the surface of the object; An image processing device comprising:

2. The image processing device according to claim 1 , wherein the auxiliary ray setting unit irradiates the auxiliary ray at a position shifted by a sub-pixel of one pixel or less from the coordinates of the surface of the object irradiated with the basic ray.

3. the shape information analysis unit calculates a fineness of the surface shape of the object based on the normal distribution on the surface of the object; The image processing device according to claim 2 , wherein the auxiliary ray setting unit determines the amount of shift of the auxiliary ray relative to the base ray in accordance with the fineness.

4. 4. The image processing device according to claim 2, wherein the auxiliary ray setting unit sets at least one auxiliary ray to be emitted to any position on the surface of the object.

5. 1. A computer-implemented image processing method comprising: calculating the geometry of the surface of the object, including the distribution of normals on the surface of the object; setting an irradiation position of a basic ray on the object for rendering the object; a step of setting an irradiation position of an auxiliary light beam, the irradiation position of which is different from that of the basic light beam and which is irradiated onto the object, in conjunction with a viewpoint position of a virtual camera; a step of controlling the illumination brightness of the basic light beam using a weight calculated based on a basic light ray normal vector obtained by irradiating the basic light beam and an auxiliary light ray normal vector obtained by irradiating the auxiliary light beam, and generating an image in which the fine shape of the surface of the object is emphasized based on the geometric shape of the surface of the object including the normal distribution on the surface of the object; An image processing method comprising:

6. calculating the geometry of the surface of the object, including the distribution of normals on the surface of the object; setting an irradiation position of a basic ray on the object for rendering the object; a step of setting an irradiation position of an auxiliary light beam, the irradiation position of which is different from that of the basic light beam and which is irradiated onto the object, in conjunction with a viewpoint position of a virtual camera; a step of controlling the illumination brightness of the basic light beam using a weight calculated based on a basic light ray normal vector obtained by irradiating the basic light beam and an auxiliary light ray normal vector obtained by irradiating the auxiliary light beam, and generating an image in which the fine shape of the surface of the object is emphasized based on the geometric shape of the surface of the object including the normal distribution on the surface of the object; An image processing program that causes a computer to execute the following.

Images