A method for applying realistic skin materials based on scanned data

Abstract

The present invention discloses a method for applying realistic skin materials based on scanned data, which relates to the technical field of realistic skin material application, and includes the following steps: S11, texture information analysis and preprocessing; S12, derivation of missing texture information; S13, texture fusion and optimization. The main purpose of the present invention is to generate the missing texture information of digital human skin materials, such as roughness, subsurface scattering and curvature, through automation technology, significantly reducing the workload of manual drawing, improving production efficiency, ensuring that the generated texture is more natural and realistic, and reducing the problem of inconsistent material effects caused by personal technical and aesthetic differences. At the same time, the present invention ensures the consistency and coordination of the generated texture with the original texture in visual effects through weight distribution and color correction technology, and provides a real-time preview function, so that users can instantly view the adjustment effect to ensure that the final effect meets expectations.

Description

Technical Field

[0001] The present invention relates to the technical field of realistic skin material application, and in particular to a method for applying realistic skin material based on scan data. Background Art

[0002] In today's Unreal Engine landscape, the rendering of digital human skin materials is gradually reaching a highly realistic and complex realm. In particular, the combination of physically based rendering (PBR) technology and digital mapping solutions generated from scanned data has become a hot research topic. This combined technology, using high-precision scan data, can capture the subtle texture and color variations of the skin, providing rich details and a high degree of realism for the production of digital human skin materials. Specifically, existing technologies include the following aspects:

[0003] 1. High-precision scanning data:

[0004] Basic scanning solution: Using basic scanning equipment, high-resolution skin surface texture and color information is obtained to generate a basic color (Diffuse) map. This basic scanning solution can provide a model and color map.

[0005] Advanced scanning solutions: Scanning hardware solutions based on algorithms or multi-light calculations can generate more detailed mapping information, including normal (normal) maps, etc. These advanced scanning devices use multi-angle and multi-light source scanning technology combined with advanced algorithms to capture the microstructure and optical properties of the skin, thereby generating high-quality maps.

[0006] 2. Manual processing of scanned textures:

[0007] To further optimize scanned textures, existing scanned textures are often manually processed and corrected. These professionally processed textures can better adapt to different project requirements, providing richer details and natural visual effects.

[0008] 3. Physically Based Rendering (PBR) Technology:

[0009] Combined with PBR technology, it ensures that the material performs more naturally and realistically under different lighting conditions.

[0010] 4. Manual drawing and adjustment:

[0011] The modeler further optimized the skin material effect by manually drawing textures and setting material properties one by one.

[0012] The main drawbacks are:

[0013] 1. Limitations of Scan Data:

[0014] Basic scanning solutions: Basic scanning solutions only capture models and color maps, but cannot generate normals or other PBR maps. This limits the realism and detail of materials. This results in a large manual rendering workload, significantly reducing the versatility of this production method, making it difficult to flexibly reuse across different projects and scenarios, severely hindering production efficiency.

[0015] Advanced scanning solution: The subject is photographed in a very short time under different lighting conditions, and then the normal and highlight information are obtained through algorithms. The scanning equipment and development costs are high. The equipment is usually not located at the company or the shooting location, making it difficult for actors to go there to collect scans, which further limits its application in actual projects. The equipment is difficult to develop independently, with a long development cycle, and is difficult to popularize.

[0016] 2. Inconsistency of manual processing:

[0017] Modelers must manually draw multiple attribute maps (such as base color, normal, roughness, and subsurface scattering) and set material parameters for each one. This process is not only time-consuming and labor-intensive, but also highly dependent on professional skills and experience. Different modelers have different understandings and visual aesthetics of attribute maps, leading to inconsistent mapping standards and material parameters. Although the visual effects may be similar, these standards vary significantly, which not only affects the consistency of the final visuals but also increases project complexity and production costs.

[0018] 3. Texture fusion effect is not ideal:

[0019] When manually blending textures, it is difficult to ensure that all textures are visually consistent and coordinated, and it is easy to have problems such as color mismatches or loss of details.

[0020] To this end, we propose a method for applying realistic skin materials based on scan data. Summary of the Invention

[0021] The purpose of the present invention is to provide a method for applying a realistic skin material based on scan data to solve the problems raised in the above background technology.

[0022] To achieve the above objectives, the present invention provides the following technical solution: a method for applying a realistic skin material based on scanned data, comprising the following steps:

[0023] S11, map information analysis and preprocessing;

[0024] S12, derivation of missing map information;

[0025] S13, texture fusion and optimization.

[0026] Preferably, the method for analyzing and preprocessing the map information in S11 includes the following steps:

[0027] S21. Import and integrate base color and normal map data to ensure uniform data format and resolution;

[0028] S22, performing color distribution and contrast analysis on the basic color map to extract color information related to skin roughness;

[0029] S23, analyzing the normal direction and intensity of the normal map to extract detailed structural information of the skin surface;

[0030] S24. Combined with the analysis results, provide key clues for the deduction of missing map information.

[0031] Preferably, the method for deriving missing map information in S12 comprises the following steps:

[0032] S31. Inferring the roughness of the skin surface based on the color and texture, and generating roughness information;

[0033] S32. Analyze the depth and saturation of the skin color in the base color map, combine it with the physiological structure of the skin, infer the relative thickness of the skin material, and generate subsurface scattering information;

[0034] S33. Generate curvature information by performing differential calculation on the normal vector in the normal map.

[0035] Preferably, the method for texture fusion and optimization in S13 includes the following steps:

[0036] S41. In the Unreal Engine's material editor, combine the automatically generated roughness, subsurface scattering, and curvature maps with the original base color and normal maps.

[0037] S42. Use weight distribution and color correction technology to ensure the consistency and coordination of the visual effects of the fused textures;

[0038] S43. Based on Unreal's real-time preview function, users can instantly view the rendering effect of the fused texture on the digital human skin material;

[0039] S44. Based on the preview results, the user can fine-tune the parameters of the texture generation algorithm to achieve the best visual effect.

[0040] Preferably, the method for generating subsurface scattering information in S32 comprises the following steps:

[0041] S51. Analyze the depth and saturation of the skin color in the base color map, and combine it with the knowledge of the physiological structure of the skin to systematically infer the relative thickness of the skin material;

[0042] S52. With the help of the normal direction information in the normal map, the material optimizes the distribution of subsurface scattering, enhances the uniformity of subsurface scattering or adjusts the intensity and range of scattering;

[0043] S53, simulating the physical process of subsurface scattering, the system generates a subsurface scattering map.

[0044] Preferably, the method for generating curvature information in S33 includes the following steps:

[0045] S61, obtaining curvature information of the skin surface by performing differential calculation on the normal vector in the normal map;

[0046] S62, referring to the detail texture in the base color map, the system corrects and refines the curvature calculation result;

[0047] S63: Generate final curvature information.

[0048] Preferably, the roughness information generation further includes the following method: when inferring the roughness of the skin surface, comprehensively analyzing the color changes and texture details in the basic color map, and the normal information in the normal map.

[0049] Preferably, the generation of subsurface scattering information also includes the following method: by analyzing the depth and saturation of the skin color in the basic color map, combined with the knowledge of the physiological structure of the skin, the relative thickness of the skin material is inferred, and further, with the help of the normal direction information in the normal map, the distribution of subsurface scattering is optimized, the uniformity of subsurface scattering is enhanced, or the intensity and range of the scattering are adjusted, thereby generating a more natural subsurface scattering map.

[0050] Preferably, the curvature information generation further includes the following method: obtaining the curvature information of the skin surface by performing differential calculation on the normal vector in the normal map.

[0051] Preferably, the texture fusion also includes the following method: in the material editor of the Unreal Engine, weight distribution and color correction technology are used to fuse the automatically generated roughness, subsurface scattering, and curvature information with the original base color and normal map.

[0052] Compared with the prior art, the present invention has the following beneficial effects:

[0053] 1. Automatically generate missing texture information: Reduce the workload of manual drawing, improve production efficiency, generate more natural and realistic texture information, and reduce the problem of inconsistent material effects caused by personal technical and aesthetic differences.

[0054] 2. Improve texture fusion effects: Ensure the visual consistency and coordination between the generated texture information and the original texture, avoid color mismatches or loss of details, and provide a real-time preview function so that users can instantly view the adjustment effects to ensure that the final effect meets expectations.

[0055] 3. Improve the versatility of materials: The generated texture information has high versatility and can be applied to different projects and scenes, reducing duplication of work and improving resource utilization. Users can fine-tune the parameters of the generation algorithm as needed to meet specific scenarios and needs, ensuring the naturalness and authenticity of the final effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 Flowchart for texture information analysis and preprocessing, missing texture information derivation, texture fusion and optimization. DETAILED DESCRIPTION

[0057] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0058] See also Figure 1 This embodiment provides a method for applying a realistic skin material based on scanned data, comprising the following steps:

[0059] S11, map information analysis and preprocessing;

[0060] S12, derivation of missing map information;

[0061] S13, texture fusion and optimization.

[0062] As a preferred embodiment, the method for analyzing and preprocessing the map information in S11 includes the following steps:

[0063] S21. First, import and integrate the base color and normal map data to ensure uniformity of data format and resolution. Based on this, the material provides a global color correction function, allowing users to adjust the hue, saturation, and brightness of the overall color, thereby ensuring that the skin color appears more natural and realistic under different lighting conditions. At the same time, the material provides a local color adjustment switch, allowing users to flexibly adjust the color correction of local areas for more precise control.

[0064] S22. Next, the color distribution and contrast analysis of the base color map is performed to accurately extract color information related to skin roughness. A custom color adjustment function is also provided, and users can precisely adjust the color value through the input box to meet specific color requirements. In addition, detailed local Mask IDs are provided in the material, covering areas such as the forehead, eyes, nose, mouth, cheeks, etc., ensuring that users can make fine adjustments to specific areas;

[0065] S23. Then, the normal map is analyzed for normal direction and intensity, and detailed structural information of the skin surface is carefully extracted. During this process, the normal map is blurred to cleverly reduce the sharpness of the details, making the normal transition more natural and avoiding overly sharp edges during rendering, thereby significantly improving the overall visual effect. At the same time, the system calculates the blending weight and blends the blurred normal map and highlight normal data with a Vector3 channel blending weight. Users can adjust the blending weight through the interface tool to achieve the best visual effect.

[0066] S24. Finally, combined with the above analysis results, this provides key clues for the derivation of missing texture information. The material provides detailed local MaskIDs, covering areas such as the forehead, eyes, nose, mouth, and cheeks, ensuring that users can make fine adjustments to specific areas to achieve more personalized and refined effects.

[0067] As a preferred embodiment, the method for deriving missing map information in S12 includes the following steps:

[0068] S31. Based on color and texture correlation modeling, the system infers the roughness of the skin surface and generates a roughness map. The key processing method is to calculate the roughness value by analyzing the color changes and texture details in the base color map. At the same time, the material generates a cavity map by analyzing the base color data, simulating the pores and tiny depressions of the skin, and superimposing the cavity information with the roughness, significantly increasing the roughness of the pores, enriching the level of detail of the roughness, and making the texture of the skin surface more realistic. In addition, the material provides a local roughness adjustment switch option, allowing users to flexibly adjust the roughness intensity of specific local areas for more refined control;

[0069] S32. Combined with the normal details in the normal map, the material further refines the derivation of roughness, especially in areas where the concave and convex structures represented by the normals are obvious, and the roughness value is appropriately increased. At the same time, by analyzing the normal data, the material can accurately identify the edge areas of the skin and increase the roughness of the edges in a targeted manner, simulating the edge transition of the skin in its natural state, so that the material can maintain a natural appearance at different viewing angles. In addition, users can adjust three main parameters through interface tools: roughness intensity, roughness contrast, and edge roughness intensity. These parameters provide basic control options, allowing users to adjust the overall roughness effect as needed to ensure that the final roughness performance meets expectations;

[0070] S33. Through shader programming, the material converts color variations and normal details into roughness values and outputs them as roughness information. Users can also adjust three key parameters through interface tools: Roughness Intensity, Roughness Contrast, and Edge Roughness Intensity. These parameters provide basic control options, allowing users to adjust the overall roughness effect as needed to ensure the final roughness performance meets expectations. Furthermore, the material provides a local roughness adjustment switch option, allowing users to flexibly adjust the roughness intensity of specific local areas for more refined control.

[0071] As a preferred embodiment, the method for texture fusion and optimization in S13 includes the following steps:

[0072] S41. In the Unreal Engine's material editor, the automatically generated roughness, subsurface scattering, and curvature information are fused with the original base color and normal map. At the same time, through blending weight calculation, the blurred normal map and specular normal data are blended with a Vector3 channel blending weight. Users can adjust the blending weight through the interface tool to achieve the best visual effect. In addition, the system provides a real-time preview function, allowing users to instantly view the rendering effect of the fused map on the digital human skin material to ensure that the final effect meets expectations;

[0073] S42. Use weight distribution and color correction technology to ensure the consistency and coordination of the visual effects of the fused maps. At the same time, through interpolation processing, the weighted normal result obtained by calculating the mixed weight is interpolated with the normal normal. The user can adjust the interpolation parameters to optimize the transition effect and avoid abrupt boundaries. In addition, the material provides highlight processing function, using Kelemen / Szirmay-Kalos specular BRDF to process the highlight effect of the skin oil layer. The user can adjust the intensity, range, color and smoothness of the highlight through the interface tools to ensure that the final highlight effect is more natural and realistic;

[0074] S43. Through the real-time preview function provided by Unreal Engine, users can instantly view the rendering effect of the fused map on the digital human skin material. At the same time, through the final blending, the interpolation result is weighted blended with the skin texture detail normal to obtain the final normal map, ensuring that the final normal effect is more realistic and natural;

[0075] S44. Based on the preview results, the user can fine-tune the parameters of the texture generation algorithm to achieve the best visual effect.

[0076] As a preferred embodiment, the method for generating subsurface scattering information in S32 includes the following steps:

[0077] S51. Analyzes the depth and saturation of the skin color in the base color map, combines it with knowledge of the physiological structure of the skin, and uses the system to infer the relative thickness of the skin material to generate subsurface scattering information. At the same time, the material calculates edge subsurface scattering by analyzing the curvature information in the normal map, ensuring that the subsurface scattering effect is more pronounced at the edge of the skin, thereby simulating the natural transmission characteristics of the skin. In addition, the material provides a local subsurface scattering switch. After turning on this option, the user can flexibly adjust the subsurface scattering intensity of the local area and make fine adjustments to specific areas (such as the nose, lips, eyes, etc.) to achieve a more personalized and refined effect.

[0078] S52. With the help of the normal direction information in the normal map, the material optimizes the distribution of subsurface scattering, enhances the uniformity of subsurface scattering, or adjusts the intensity and range of scattering. At the same time, a local subsurface scattering switch is provided. After turning on this option, the user can flexibly adjust the subsurface scattering intensity of the local area and make fine adjustments to specific areas (such as the nose, lips, eyes, etc.) to achieve a more personalized and refined effect. In addition, the user can adjust the intensity, contrast, curvature intensity and edge subsurface scattering intensity of the subsurface scattering through the interface tools. These parameters provide fine control options, allowing users to adjust the subsurface scattering effect as needed to ensure that the final subsurface scattering effect is more natural and realistic;

[0079] S53 simulates the physical process of subsurface scattering, and the system generates a subsurface scattering map. Users can also adjust the intensity, contrast, curvature, and edge subsurface scattering intensity of the subsurface scattering through interface tools. These parameters provide fine-grained control options, allowing users to adjust the subsurface scattering effect as needed, ensuring a more natural and realistic final subsurface scattering effect. Furthermore, the material provides a local subsurface scattering switch. By turning this option on, users can flexibly adjust the subsurface scattering intensity of a local area, making fine adjustments to specific areas (such as the nose, lips, eyes, etc.) for a more personalized and refined effect.

[0080] As a preferred embodiment, the method for generating curvature information in S33 includes the following steps:

[0081] S61. The curvature information of the skin surface is obtained by performing differential calculation on the normal vectors in the normal map. The specific steps include sampling the normal vector, calculating the gradient of the normal, calculating the curvature, and referencing the detailed texture in the base color map to correct and refine the curvature calculation results to generate the final curvature map, which more accurately reflects the microstructure and morphological characteristics of the skin. In addition, the material provides detailed local MaskID, and users can make fine adjustments to specific areas to achieve more personalized and refined effects;

[0082] S62, referring to the detailed texture in the base color map, the system corrects and refines the curvature calculation results. At the same time, the material provides detailed local MaskID, allowing users to fine-tune specific areas to achieve more personalized and refined effects. In addition, users can adjust the curvature intensity through interface tools to ensure that the final curvature effect is more natural and realistic, improving the overall texture of the skin material;

[0083] S63 generates the final curvature information. Users can adjust the curvature strength through interface tools to ensure a more natural and realistic final curvature, enhancing the overall texture of the skin material. Furthermore, the material provides detailed local MaskIDs, allowing users to fine-tune specific areas for a more personalized and refined effect.

[0084] As a preferred embodiment, a unique processing method for generating roughness information is also included:

[0085] When inferring the roughness of the skin surface, a comprehensive analysis is performed of the color variations and texture details in the base color map, as well as the normal information in the normal map. In particular, in areas where the bumps and depressions represented by the normals are noticeable, the roughness value is appropriately increased to more accurately simulate the microstructure of the skin surface. A Cavity map is also generated by analyzing the base color data to simulate the pores and tiny depressions of the skin. This Cavity map is then overlaid with the roughness information, significantly increasing the roughness of the pores and enriching the level of detail in the roughness, making the skin surface texture more realistic. Furthermore, a local roughness adjustment switch option is provided in the material, allowing users to flexibly adjust the roughness intensity of specific local areas for even finer control.

[0086] As a preferred embodiment, a unique processing method for generating subsurface scattering information is also included:

[0087] By analyzing the depth and saturation of skin color in the base color map, combined with knowledge of the physiological structure of the skin, the relative thickness of the skin material is inferred. Furthermore, with the help of the normal direction information in the normal map, the distribution of subsurface scattering is optimized, the uniformity of subsurface scattering is enhanced, or the intensity and range of scattering are adjusted, thereby generating a more natural subsurface scattering map. At the same time, by analyzing the curvature information in the normal map, edge subsurface scattering is calculated to ensure that the subsurface scattering effect is more pronounced in the edge areas of the skin, thereby simulating the natural transmission characteristics of the skin. In addition, the material provides a local subsurface scattering switch. After turning on this option, the user can flexibly adjust the subsurface scattering intensity of the local area and make fine adjustments to specific areas (such as the nose, lips, eyes, etc.) to achieve a more personalized and refined effect.

[0088] As a preferred embodiment, a unique processing method for generating curvature information is also included:

[0089] The curvature information of the skin surface is obtained by performing differential calculations on the normal vectors in the normal map. The specific steps include sampling the normal vector, calculating the gradient of the normal, calculating the curvature, and referring to the detailed texture in the base color map to correct and refine the curvature calculation results to generate the final curvature map, which more accurately reflects the microstructure and morphological characteristics of the skin. At the same time, a detailed local MaskID is provided, and users can make fine adjustments to specific areas to achieve more personalized and refined effects. In addition, users can adjust the curvature intensity through the interface tools to ensure that the final curvature effect is more natural and realistic, and enhance the overall texture of the skin material.

[0090] As a preferred embodiment, a unique processing method for texture fusion is also included:

[0091] In Unreal Engine's material editor, weighted distribution and color correction techniques are employed to fuse automatically generated roughness, subsurface scattering, and curvature information with the original base color and normal maps. Through Unreal Engine's real-time preview feature, users can instantly view how the fused maps appear on the digital human skin material and fine-tune the map generation algorithm parameters based on the preview results to achieve optimal visual effects. The system also provides highlight processing, using the Kelemen / Szirmay-Kalos specular BRDF to process the highlights of the skin's oil layer. Users can adjust the intensity, range, color, and smoothness of the highlights through interface tools to ensure a more natural and realistic final highlight effect.

[0092] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0093] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for applying realistic skin material based on scanned data, characterized in that: The following steps are involved: S11, map information analysis and preprocessing; S12, derivation of missing map information; S13, texture fusion and optimization; The method for analyzing and preprocessing the map information in S11 includes the following steps: S21. Import and integrate base color and normal map data to ensure uniform data format and resolution; S22, performing color distribution and contrast analysis on the basic color map to extract color information related to skin roughness; S23, analyzing the normal direction and intensity of the normal map to extract detailed structural information of the skin surface; S24. Combine the analysis results to provide key clues for the deduction of missing map information; The method for deriving missing map information in S12 comprises the following steps: S31. Inferring the roughness of the skin surface based on the color and texture, and generating roughness information; S32. Analyze the depth and saturation of the skin color in the base color map, combine it with the physiological structure of the skin, infer the relative thickness of the skin material, and generate subsurface scattering information; S33, generating curvature information by performing differential calculation on the normal vector in the normal map; The method for texture fusion and optimization in S13 includes the following steps: S41. In the Unreal Engine's material editor, combine the automatically generated roughness, subsurface scattering, and curvature maps with the original base color and normal maps. S42. Use weight distribution and color correction technology to ensure the consistency and coordination of the visual effects of the fused textures; S43. Based on Unreal's real-time preview function, users can instantly view the rendering effect of the fused texture on the digital human skin material; S44. Based on the preview results, the user can fine-tune the parameters of the texture generation algorithm to achieve the best visual effect.

2. The method for applying a realistic skin material based on scanned data according to claim 1, characterized in that: The method for generating subsurface scattering information in S32 comprises the following steps: S51. Analyze the depth and saturation of the skin color in the base color map, and combine it with the knowledge of the physiological structure of the skin to systematically infer the relative thickness of the skin material; S52. With the help of the normal direction information in the normal map, the material optimizes the distribution of subsurface scattering, enhances the uniformity of subsurface scattering or adjusts the intensity and range of scattering; S53, simulating the physical process of subsurface scattering, the system generates a subsurface scattering map.

3. The method for applying a realistic skin material based on scanned data according to claim 2, characterized in that: The method for generating curvature information in S33 comprises the following steps: S61, obtaining curvature information of the skin surface by performing differential calculation on the normal vector in the normal map; S62, referring to the detail texture in the base color map, the system corrects and refines the curvature calculation result; S63: Generate final curvature information.

4. The method for applying a realistic skin material based on scanned data according to claim 3, characterized in that: Roughness information generation also includes the following method: when inferring the roughness of the skin surface, a comprehensive analysis of color changes and texture details in the base color map and normal information in the normal map is performed.

5. The method for applying a realistic skin material based on scanned data according to claim 4, characterized in that: Subsurface scattering information generation also includes the following methods: by analyzing the depth and saturation of skin color in the base color map, combined with knowledge of the physiological structure of the skin, the relative thickness of the skin material is inferred. Furthermore, with the help of the normal direction information in the normal map, the distribution of subsurface scattering is optimized, the uniformity of subsurface scattering is enhanced, or the intensity and range of scattering are adjusted, thereby generating a more natural subsurface scattering map.

6. The method for applying a realistic skin material based on scanned data according to claim 5, characterized in that: The curvature information generation also includes the following method: obtaining the curvature information of the skin surface by performing differential calculation on the normal vector in the normal map.

7. The method for applying a realistic skin material based on scanned data according to claim 6, characterized in that: Texture fusion also includes the following methods: In the Unreal Engine's material editor, weight distribution and color correction technology are used to fuse the automatically generated roughness, subsurface scattering, and curvature information with the original base color and normal maps.

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