Scanning data-based realistic skin material application method

Abstract

The invention discloses a realistic skin material application method based on scanning data, and relates to the technical field of realistic skin material application, and the method comprises the following steps: S11, map information analysis and preprocessing; s12, deducing missing map information; and S13, fusing and optimizing the chartlet. The main purpose of the invention is to generate missing map information of digital human skin materials through an automation technology, such as roughness, subsurface scattering, curvature and the like, significantly reduce the workload of manual drawing, improve the production efficiency, ensure that the generated map is more natural and real, and improve the quality of the digital human skin materials. And the problem of inconsistent material effects caused by personal skill and aesthetic differences is reduced. Meanwhile, through weight distribution and color correction technologies, the consistency and coordination of the generated chartlet and the original chartlet in visual effect are ensured, a real-time preview function is provided, a user can check the adjustment effect in real time, and it is ensured that the final effect meets the expectation.

Description

Technical Field

[0001] The present invention relates to the technical field of realistic skin material applications, and specifically to a method for applying realistic skin materials based on scanned data. Background Art

[0002] In the field of current Unreal Engines, the rendering of digital human skin materials is gradually moving towards a highly realistic and complex realm. Especially the combination of physically based rendering (PBR) technology and digital texture mapping schemes generated based on scanned data has become a hot topic and focus of research. This combined technology can capture the fine textures and color variations of the skin through high-precision scanned data, providing rich details and a high degree of realism for the production of digital human skin materials. Specifically, the existing technologies mainly include the following aspects: 1. High-precision scanned data: Basic scanning scheme: Using basic scanning equipment to obtain high-resolution skin surface textures and color information, and generating a base color (Diffuse) map. This basic scanning scheme can provide a model and a color map.

[0003] Advanced scanning scheme: A scanning hardware scheme based on algorithms or multi-light position calculations can generate more detailed texture information, including normal maps, etc. These advanced scanning devices can capture the microscopic structure and optical properties of the skin through multi-angle and multi-light source scanning technologies, combined with advanced algorithms, thus generating high-quality maps.

[0004] 2. Manual processing of scanned textures: To further optimize the scanned textures, manual processing and correction are usually performed on the existing scanned textures. These professionally processed textures can better meet the requirements of different projects, providing richer details and a more natural visual effect.

[0005] 3. Physically based rendering (PBR) technology: Combining PBR technology to ensure that the performance of the material is more natural and realistic under different lighting conditions.

[0006] 4. Manual drawing and adjustment: Modelers further optimize the effect of the skin material by manually drawing textures and setting material properties one by one.

[0007] The main drawbacks are as follows: 1. Limitations of scanned data: Basic Scanning Solution: The basic scanning solution can only obtain the model and color map, and cannot generate normal maps or other PBR maps, which limits the realism and detail performance of the material. This leads to a large amount of manual drawing work, and the versatility of this production method is also greatly reduced. It is difficult to be flexibly reused in different projects and scenarios, seriously restricting the improvement of production efficiency.

[0008] Advanced Scanning Solution: The object to be photographed is photographed by different light positions in a very short time, and then the normal and specular information is obtained through algorithms. The development and use costs of this scanning device are high; the device is usually not in the company or the shooting location, and it is difficult for actors to go there for acquisition and scanning, which further limits its application in actual projects; the self-developed device has great difficulty and a long cycle, and it is difficult to popularize.

[0009] 2. Inconsistency in Manual Processing: The modeler needs to manually draw multiple property maps (such as base color, normal, roughness, subsurface scattering, etc.) and set the material parameters one by one. This process is not only time-consuming and laborious, but also highly dependent on professional skills and experience. Different modelers have different understandings and visual aesthetics of property maps, resulting in inconsistent map standards and material parameters. Although the visual effects may be similar, the standard differences are large, which not only affects the unity of the final visual effect, but also increases the project complexity and production cost.

[0010] 3. Unsatisfactory Map Blending Effect: When manually blending maps, it is very difficult to ensure the consistency and coordination of all maps in terms of visual effects, and problems such as color mismatch or detail loss are likely to occur.

[0011] Therefore, we propose a method for applying realistic skin materials based on scanning data. Summary of the Invention

[0012] The purpose of the present invention is to provide a method for applying realistic skin materials based on scanning data to solve the problems raised in the above background technology.

[0013] To achieve the above purpose, the present invention provides the following technical solution: A method for applying realistic skin materials based on scanning data, including the following steps: S11. Map Information Analysis and Preprocessing; S12. Deduction of Missing Map Information; S13. Map Blending and Optimization.

[0014] Preferably, the method for map information analysis and preprocessing in S11 includes the following steps: S21. Import and integrate the base color and normal map data to ensure the unity of 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 strength of the normal map to extract detailed structural information of the skin surface; S24. Combined with the analysis results, provide key clues for the deduction of missing map information.

[0015] Preferably, 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, analyzing the depth and saturation of the skin color in the basic color map, combining the knowledge of the physiological structure of the skin, inferring the relative thickness of the skin material, and generating subsurface scattering information; S33. Generate curvature information by performing differential calculation on the normal vector in the normal map.

[0016] Preferably, the method for texture fusion and optimization in S13 comprises the following steps: S41. In the material editor of Unreal Engine, merge 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 the real-time preview function of Unreal, 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.

[0017] Preferably, the method for generating subsurface scattering information in S32 comprises the following steps: S51, analyzing the depth and saturation of the skin color in the basic color map, and combining the knowledge of the physiological structure of the skin, the system infers 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.

[0018] Preferably, 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 detailed texture in the base color map, the system corrects and refines the curvature calculation results; S63. Generate the final curvature information.

[0019] Preferably, the generation of roughness information further includes the following method: when inferring the roughness of the skin surface, comprehensively analyze the color changes and texture details in the base color map, as well as the normal information in the normal map.

[0020] Preferably, the generation of subsurface scattering information further includes the following method: by analyzing the light and saturation of the skin color in the base color map, and combining the knowledge of the physiological structure of the skin, infer the relative thickness of the skin material. Further, with the help of the normal direction information in the normal map, optimize the distribution of subsurface scattering, enhance the uniformity of subsurface scattering or adjust the intensity and range of scattering, so as to generate a more natural subsurface scattering map.

[0021] Preferably, the generation of curvature information further includes the following method: by performing differential calculation on the normal vectors in the normal map, obtain the curvature information of the skin surface.

[0022] Preferably, the map fusion further includes the following method: in the material editor of the Unreal Engine, adopt weight assignment and color correction techniques to fuse and configure the automatically generated roughness, subsurface scattering, curvature information with the original base color and normal map.

[0023] Compared with the prior art, the beneficial effects of the present invention are: 1. Automatically generate missing map information: reduce the workload of manual drawing, improve production efficiency, the generated map information is more natural and realistic, and reduce the problem of inconsistent material effects caused by individual technical and aesthetic differences.

[0024] 2. Improve the map fusion effect: ensure the consistency and coordination of the generated map information and the original map in visual effects, avoid problems such as color mismatch or detail loss, provide a real-time preview function, and users can immediately view the adjustment effect to ensure that the final effect meets expectations.

[0025] 3. Improve the versatility of materials: the generated map information has high versatility, can be applied to different projects and scenes, reduce repetitive work, improve resource utilization rate, and users can fine-tune the parameters of the generation algorithm according to needs to meet specific scenarios and requirements, ensuring the naturalness and authenticity of the final effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a flowchart of map information analysis and preprocessing, derivation of missing map information, map fusion and optimization. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0028] Please refer to Figure 1 , this embodiment provides a method for applying realistic skin materials based on scan data. A method for applying realistic skin materials based on scan data includes the following steps: S11. Analysis and preprocessing of texture information; S12. Deduction of missing texture information; S13. Texture fusion and optimization.

[0029] As a preferred implementation manner, the method for analyzing and preprocessing texture information in S11 includes the following steps: S21. First, import and integrate the base color and normal map data to ensure the unity of data format and resolution. On this basis, the material provides a global color correction function, allowing users to adjust the hue, saturation, and brightness of the overall color, so as to ensure that the skin color appears more natural and realistic under different lighting conditions. At the same time, a local color adjustment switch is provided in the material, and users can flexibly adjust the color correction of local areas to achieve more precise control; S22. Next, analyze the color distribution and contrast of the base color texture, and accurately extract the color information related to skin roughness. At the same time, a custom color adjustment function is provided, and users can precisely adjust the color value through the input box to meet specific color requirements. In addition, detailed local MaskIDs are provided in the material, covering areas such as the forehead, eyes, nose, mouth, cheeks, etc., ensuring that users can make fine adjustments for specific areas; S23. Then, analyze the normal direction and intensity of the normal map, and carefully extract the detailed structure information of the skin surface. During this process, blur the normal map to subtly reduce the sharpness of the details, make the normal transition more natural, and avoid overly sharp edges during rendering, thereby significantly improving the overall visual effect. At the same time, the system mixes the blurred normal map and the specular normal data with a mixing weight of a Vector3 channel through mixing weight calculation, and users can adjust the mixing weight through the interface tool to achieve the best visual effect; S24. Finally, combining the above analysis results 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, cheeks, etc., ensuring that users can make fine adjustments for specific areas to achieve more personalized and refined effects.

[0030] As a preferred implementation, the method for deriving missing texture information in S12 includes the following steps: S31. Based on color-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 to simulate the pores and micro-depressions of the skin, and superimposes the Cavity information with the roughness, significantly increasing the roughness of the pores and enriching the detail level of the roughness, 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 to achieve more precise control; S32. Combining the normal details in the normal map, the material further refines the derivation of roughness, especially in areas with obvious concave-convex structures represented by the normal. 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 accordingly to simulate the edge transition of the skin in its natural state, ensuring that the material maintains a natural appearance from different perspectives. In addition, users can adjust three main parameters through the interface tool: roughness intensity, roughness contrast, and edge roughness intensity. These parameters provide basic control options, enabling users to adjust the overall roughness effect according to their needs and ensuring that the final roughness performance meets expectations; S33. Through Shader programming, the material converts color changes and normal details into roughness values and outputs them as roughness information. At the same time, users can adjust three main parameters through the interface tool: roughness intensity, roughness contrast, and edge roughness intensity. These parameters provide basic control options, enabling users to adjust the overall roughness effect according to their needs and ensuring that the final roughness performance meets expectations. In addition, the material provides a local roughness adjustment switch option, allowing users to flexibly adjust the roughness intensity of specific local areas to achieve more precise control.

[0031] As a preferred implementation, the method for texture fusion and optimization in S13 includes the following steps: S41. In the material editor of Unreal Engine, the automatically generated roughness, subsurface scattering, and curvature information are fused with the original base color and normal map. At the same time, through the mixed weight calculation, the blurred normal map and highlight normal data are mixed with a Vector3 channel mixing weight. The user can adjust the mixing weight through the interface tool to achieve the best visual effect. In addition, the system provides a real-time preview function, and the user can instantly view the presentation effect of the fused map on the digital human skin material to ensure that the final effect meets expectations; 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 highlight intensity, range, color and smoothness through the interface tools to ensure that the final highlight effect is more natural and realistic; 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; S44. Based on the preview results, the user can fine-tune the parameters of the texture generation algorithm to achieve the best visual effect.

[0032] As a preferred implementation, 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, combine the knowledge of the physiological structure of the skin, and the system infers the relative thickness of the skin material to generate subsurface scattering information. At the same time, the material calculates the edge subsurface scattering by analyzing the curvature information in the normal map to ensure that the subsurface scattering effect is more obvious in the edge area 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; S52. By leveraging 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. Meanwhile, a local subsurface scattering switch is provided. After the user enables this option, they can flexibly adjust the subsurface scattering intensity in a 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 subsurface scattering through the interface tool. These parameters provide fine control options, allowing the user to adjust the subsurface scattering effect according to their needs and ensure that the final subsurface scattering effect is more natural and realistic; S53. Simulate the physical process of subsurface scattering, and the system generates a subsurface scattering map. Meanwhile, the user can adjust the intensity, contrast, curvature intensity, and edge subsurface scattering intensity of subsurface scattering through the interface tool. These parameters provide fine control options, allowing the user to adjust the subsurface scattering effect according to their needs and ensure that the final subsurface scattering effect is more natural and realistic. In addition, the material provides a local subsurface scattering switch. After the user enables this option, they can flexibly adjust the subsurface scattering intensity in a local area and make fine adjustments to specific areas (such as the nose, lips, eyes, etc.) to achieve a more personalized and refined effect.

[0033] As a preferred implementation manner, the method for generating curvature information in S33 includes the following steps: S61. By performing differential calculation on the normal vectors in the normal map, obtain the curvature information of the skin surface. The specific steps include sampling the normal vectors, 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 result, generating the final curvature map, which more accurately reflects the microscopic structure and morphological characteristics of the skin. In addition, the material provides detailed local MaskIDs, and the user can make fine adjustments for specific areas to achieve a more personalized and refined effect; S62. Refer to the detailed texture in the base color map, and the system corrects and refines the curvature calculation result. Meanwhile, the material provides detailed local MaskIDs, and the user can make fine adjustments for specific areas to achieve a more personalized and refined effect. In addition, the user can adjust the curvature intensity through the interface tool to ensure that the final curvature effect is more natural and realistic and enhance the overall texture of the skin material; S63. Generate the final curvature information. Meanwhile, the user can adjust the curvature intensity through the interface tool to ensure that the final curvature effect is more natural and realistic and enhance the overall texture of the skin material. In addition, the material provides detailed local MaskIDs, and the user can make fine adjustments for specific areas to achieve a more personalized and refined effect.

[0034] As a preferred embodiment, it also includes a unique processing method for generating roughness information: When inferring the roughness of the skin surface, comprehensively analyze the color changes and texture details in the base color map, as well as the normal information in the normal map. Especially in areas where the bump structure represented by the normal is obvious, appropriately increase the roughness value to more accurately simulate the microscopic structure of the skin surface. Also generate a Cavity map by analyzing the base color data to simulate the pores and micro depressions of the skin, and overlay the Cavity map with the roughness information, significantly increasing the roughness of the pores and enriching the detail level of the roughness, making the texture of the skin surface more realistic. In addition, a local roughness adjustment switch option is provided in the material, and users can flexibly adjust the roughness intensity of specific local areas to achieve more precise control.

[0035] As a preferred embodiment, it also includes a unique processing method for generating subsurface scattering information: By analyzing the light and saturation of the skin color in the base color map and combining the knowledge of the physiological structure of the skin, infer the relative thickness of the skin material. Further, with the help of the normal direction information in the normal map, optimize the distribution of subsurface scattering, enhance the uniformity of subsurface scattering or adjust the intensity and range of scattering, so as to generate a more natural subsurface scattering map. At the same time, by analyzing the curvature information in the normal map, calculate the edge subsurface scattering to ensure that the subsurface scattering effect is more obvious in the edge area of the skin, thus simulating the natural transmission characteristics of the skin. In addition, a local subsurface scattering switch is provided in the material. After the user enables this option, they 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 precise effect.

[0036] As a preferred embodiment, it also includes a unique processing method for generating curvature information: By performing a difference calculation on the normal vectors in the normal map, obtain the curvature information of the skin surface. The specific steps include sampling the normal vectors, 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, generating the final curvature map, which more accurately reflects the microscopic structure and morphological characteristics of the skin. At the same time, detailed local MaskIDs are provided, and users can make fine adjustments for specific areas to achieve a more personalized and precise effect. In addition, users can adjust the curvature intensity through the interface tool to ensure that the final curvature effect is more natural and realistic, enhancing the overall texture of the skin material.

[0037] As a preferred embodiment, it also includes a unique processing method for map fusion: In the material editor of the Unreal Engine, by using weight allocation and color correction techniques, roughness, subsurface scattering, and curvature information will be automatically generated and configured by integrating with the original base color and normal map. Through the real-time preview function of the Unreal Engine, users can instantly view the rendering effect of the integrated texture on the digital human skin material, and fine-tune the parameters of the texture generation algorithm according to the preview results to achieve the best visual effect. The system also provides a specular processing function, using the Kelemen / Szirmay-Kalos specular BRDF to process the specular effect of the skin oil layer. Users can adjust the intensity, range, color, and smoothness of the specular through the interface tool to ensure that the final specular effect is more natural and realistic.

[0038] It should be noted that in this article, relational terms such as first and second are only used 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 term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0039] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present 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, missing map information derivation; S13. Texture fusion and optimization.

2. The method for applying a realistic skin material based on scanned data according to claim 1, characterized in that: The method for analyzing and preprocessing the map information in S11 comprises 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 strength of the normal map to extract detailed structural information of the skin surface; S24. Combined with the analysis results, provide key clues for the deduction of missing map information.

3. The method for applying a realistic skin material based on scanned data according to claim 2, characterized in that: 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, analyzing the depth and saturation of the skin color in the basic color map, combining the knowledge of the physiological structure of the skin, inferring the relative thickness of the skin material, and generating subsurface scattering information; S33. Generate curvature information by performing differential calculation on the normal vector in the normal map.

4. The method for applying a realistic skin material based on scanned data according to claim 3, characterized in that: The method for texture fusion and optimization in S13 comprises the following steps: S41. In the material editor of Unreal Engine, merge 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 the real-time preview function of Unreal, 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.

5. The method for applying a realistic skin material based on scanned data according to claim 4, characterized in that: The method for generating subsurface scattering information in S32 comprises the following steps: S51, analyzing the depth and saturation of the skin color in the basic color map, and combining the knowledge of the physiological structure of the skin, the system infers 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.

6. The method for applying a realistic skin material based on scanned data according to claim 5, 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.

7. The method for applying a realistic skin material based on scanned data according to claim 6, characterized in that: Roughness information generation also includes the following method: when inferring the roughness of the skin surface, the color changes and texture details in the base color map and the normal information in the normal map are comprehensively analyzed.

8. The method for applying a realistic skin material based on scanned data according to claim 7, 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 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 scattering are adjusted, thereby generating a more natural subsurface scattering map.

9. The method for applying a realistic skin material based on scanned data according to claim 8, 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.

10. The method for applying a realistic skin material based on scanned data according to claim 9, 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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