9 results about "Subsurface scattering" patented technology

The invention discloses a quantitative detection method for anti-perspective performance of a textile in a complex light environment, and belongs to the technical field of new material detection, a micro gap is arranged between the textile to be detected and a variable-frequency gray scale target to simulate a non-clinging state when clothes are worn and excite Fresnel diffraction and subsurface scattering effects, and the anti-perspective performance of the textile is detected. Complex illumination conditions such as backlight and sidelight are simulated by adjusting the light intensity ratio, and after a target perspective image is acquired by using an image acquisition unit, the modulation transfer function attenuation rate of a to-be-detected textile to the target is calculated, so that the anti-perspective performance of the textile is quantitatively represented; the interference of glare on the surface of the high-gloss fabric is effectively eliminated by introducing an orthogonal polarization modulation technology, and a detection result is highly consistent with the visual perception of human eyes by adopting a specific light source spectrum simulating the skin color of a human body; compared with a traditional light transmittance method, the method has the advantages that the dimension crossing from luminous flux measurement to image information fidelity evaluation is realized, and the accuracy, reliability and practicability of detection are remarkably improved.

The invention relates to the technical field of fruit quality detection, and discloses a fruit quality detection method and system based on multispectral structured light, and the method comprises the steps: firstly collecting a structured light image sequence and a spectral intensity image of a to-be-detected fruit, and solving an initial truncation phase field; performing subsurface scattering phase reverse compensation on the initial truncation phase field by using a spectral intensity image, and reconstructing a unit normal vector field of the surface of the fruit to be measured through unwrapping; carrying out physical reverse compensation on the spectral intensity image by utilizing a unit normal vector field and an illumination direction vector, and decoupling to obtain real spectral reflectivity distribution; and finally, outputting a comprehensive grading result of the to-be-detected fruit by fusing the geometrical morphology characteristics and the spectrum biochemical characteristics. According to the method, the phase is corrected by calculating the gray absorption item and the gradient scattering item of the image, so that the problem of phase drift caused by light permeation due to the semitransparent fruit skin is effectively solved, the depth measurement error caused by light diffusion in a medium is eliminated, and the fruit detection precision is further improved.

This invention discloses a method and system for detecting surface defects in a transparent hood based on three-dimensional scanning, belonging to the field of three-dimensional optical measurement technology. The method includes steps such as optical characteristic pre-scanning and partitioning, adaptive viewing angle planning and dynamic scanning, scattering sensing registration and signal separation, surface reconstruction and defect extraction. By establishing an anisotropic scattering model and calculating the scannability index, this invention solves the technical problem of traditional scanning viewing angle planning that only considers geometric visibility while neglecting the optical characteristics of the transparent material. It achieves an improvement in scanning viewing angle from geometric reachability to optical detectability, increasing the point cloud integrity rate and multi-view stitching accuracy in areas with high curvature. By dynamically adjusting laser power, exposure time, polarization state, focal length, depth of field, and sampling density in real time based on optical characteristic partitioning, it achieves adaptive matching between scanning parameters and the material's optical response, effectively suppressing subsurface scattering interference and improving the microcrack detection rate.

The invention discloses a mutton color decision-making method and system based on fuzzy logic, particularly relates to the technical field of computer vision, and is used for solving the problem that according to an existing mutton color automatic grading method, color feature distortion is caused by mirror reflection and subsurface scattering, and the grading accuracy is affected. A mutton surface digital image is collected and preprocessed, hue, saturation and brightness parameters based on an HSV color space are extracted to serve as an initial color feature set, a specular reflection highlight area and a subsurface scattering diffusion area are recognized, edge interweaving complexity and effective scattering path depth are calculated, and a high-definition image is obtained. And generating a color distortion compensation coefficient based on the parameters, carrying out linear adjustment on an initial color feature by using the coefficient, inputting the corrected feature into a fuzzy logic decision system, and outputting a mutton color grade result.

The present disclosure provides a model rendering method and device, computer equipment and a storage medium, wherein the method comprises: obtaining a three-dimensional model of a target face, and obtaining target rendering information corresponding to the three-dimensional model; the three-dimensional model comprises a plurality of vertices; the target rendering information is used to represent the display light intensity of each target vertex in the subsurface scattering range corresponding to the three-dimensional model; based on the target rendering information and a color tendency diagram of subsurface scattering, the color tendency corresponding to each target vertex is determined; the color tendency diagram is used to describe the mapping relationship between different display light intensities and color tendencies; based on the color tendency corresponding to each target vertex, the three-dimensional model is rendered to obtain a target rendering model of the three-dimensional model.

The application provides a rendering method and device of a three-dimensional model, equipment and a medium, and relates to the technical field of computers. The method comprises the following steps: assigning a physical-based rendering (PBR) material with a gelatinous texture to an initial three-dimensional model, adding a preset surface color map to the initial three-dimensional model, and obtaining a three-dimensional model to be rendered; obtaining a first rendering parameter based on a subsurface scattering algorithm; determining a first rendering area and a second rendering area of the three-dimensional model to be rendered based on a preset reflection algorithm, and determining a second rendering parameter corresponding to each pixel point; and rendering according to the first rendering parameter and the second rendering parameter to obtain a target three-dimensional model, so that the target three-dimensional model can present a subsurface scattering effect under different viewing angles through a regional rendering operation, and can also present a rendering effect of weak light transmission in thick places and good light transmission in thin places, so that the gelatinous texture is more realistic, and the rendering effect is not affected by viewing angle switching.

The application discloses a mutton color decision method and system based on fuzzy logic, and particularly relates to the technical field of computer vision, and is used for solving the problem that the existing mutton color automatic grading method is influenced by the color feature distortion caused by specular reflection and subsurface scattering and the grading accuracy; the mutton color decision method and system are realized by the following steps: collecting a digital image of a mutton surface and performing pretreatment, extracting hue, saturation and brightness parameters based on an HSV color space as an initial color feature set, identifying a specular reflection highlight area and a subsurface scattering diffuse area, calculating edge interweaving complexity and effective scattering path depth, generating a color distortion compensation coefficient based on the parameters, applying the coefficient to linearly adjust the initial color feature, and inputting the corrected feature into a fuzzy logic decision system to output a mutton color grade result.

The application relates to the technical field of fruit quality detection, and discloses a fruit quality detection method and system based on a multi-spectrum structured light, which first collects a structured light image sequence and a spectral intensity image of a fruit to be detected, and calculates an initial truncated phase field; then performs inverse compensation of a subsurface scattering phase on the initial truncated phase field by using the spectral intensity image, and reconstructs a unit normal vector field of a surface of the fruit to be detected through unwrapping; then performs physical inverse compensation on the spectral intensity image by using the unit normal vector field and an illumination direction vector, and decouples to obtain a real spectral reflectance distribution; and finally fuses geometric and spectral biochemical features to output a comprehensive grading result of the fruit to be detected. The application corrects the phase by calculating a gray absorption term and a gradient scattering term of the image, effectively solves the phase drift problem caused by the penetration of light on the translucent fruit skin, eliminates the depth measurement error caused by the light diffusion in the medium, and further improves the fruit detection precision.

The application discloses a three-dimensional virtual image expression animation generation method based on a real feeling rendering technology, and comprises the following steps: inputting a speech segment and a three-dimensional virtual image head grid model, driving the head grid model to deform by using a speech signal, and generating a three-dimensional virtual image grid model sequence corresponding to the speech signal and containing expressions; inputting a single face image, and generating a diffuse reflection map conforming to a topological structure of the three-dimensional virtual image head grid model; respectively acquiring a specular reflection component, a subsurface scattering component and a transmission component, and constructing a skin rendering model based on the specular reflection component, the subsurface scattering component and the transmission component; rendering the three-dimensional virtual image grid model sequence based on the skin rendering model, and outputting a three-dimensional virtual image expression animation sequence with a high real feeling skin effect. The application meets various needs in practical applications.