7 results about "Anisotropic filtering" patented technology

This invention discloses a method and system for detecting defects on highly reflective metal surfaces based on industrial vision, relating to the field of industrial vision. The method includes: scanning along the longitudinal direction of a rolling linear guide at a preset speed using a line-scan imaging unit to acquire an original polarized image sequence covering the polarization angle corresponding to the sliding surface of the guide; analyzing the original polarized image sequence, extracting the texture direction field, performing directional anisotropic filtering on the original polarized image sequence, and outputting an enhanced image sequence; using a preset sliding window to progressively capture local image blocks pixel by pixel, and using a scratch probability assessment model to output the probability value of the center pixel belonging to a minor scratch, generating a probability distribution map; performing connected component analysis, and determining continuous pixel regions with probability values ​​exceeding a dynamic activation threshold as minor scratch regions, thereby obtaining the minor scratch defect detection result. This method solves the problems of high false negative rates in highly reflective environments, the inability of fixed thresholds to adapt to reflective environments, resulting in extremely low detection accuracy and strong imaging interference.

The invention is entitled "Graphics Texture Mapping". When performing anisotropic filtering when sampling a texture to provide output sample texture values used in rendering output in a graphics processing system, the number of positions at which the texture is to be sampled along an anisotropic direction in the texture along which samples are to be taken in the texture is determined by determining the square root of the coefficients F of an ellipse of the form Ax 2 + Bxy + Cy 2 = F, the ellipse corresponding to a projection onto a surface to which the texture is to be applied of a sample point at which the texture is sampled, and using the determined square root of the coefficients F of the ellipse to determine the number of positions at which samples should be taken in the texture along the anisotropic direction.

This invention provides an image background noise suppression method based on anisotropic filtering with local contrast, belonging to the field of image processing technology. The method includes: Step S1, calculating the average gray value of pixels in a central neighborhood within a first specific range centered on the current pixel, obtaining the average gray value of the central neighborhood; Step S2, calculating the average gray value of background pixels in eight surrounding background neighborhoods within a second specific range centered on the current pixel, obtaining the average gray value of each of the eight background neighborhoods; Step S3, calculating the differences between the average gray value of the eight background neighborhoods and the average gray value of the central neighborhood in four directions, based on the average gray value of the central neighborhood and the average gray value of the eight background neighborhoods; Step S4, determining the gray value of the current pixel based on the differences in the four directions. This invention provides stronger local signal-to-noise ratio gain, clearer target boundaries, lower average background brightness, and faster calculation speed, enabling it to respond to high frame rate processing requirements.

This invention discloses a medical image segmentation method for urinary stones based on region connectivity, belonging to the field of medical image processing technology, to solve the problems of high-density bone interference and topological fragmentation in stone segmentation. First, a piecewise weighted mapping function is constructed to adaptively adjust the window width and perform anisotropic filtering on the image, generating a bone suppression feature map. Then, a maximum stable extremum region algorithm combined with anatomical priors is used to extract high-confidence seed points. A fast traversal algorithm is executed using a constructed gradient resistance field to detect geodesic temporal field abrupt changes to define boundaries, generating a simply connected mask. Finally, three-dimensional dense morphology and texture consistency features are fused for weighted discrimination to remove vascular calcification artifacts. This invention ensures the topological connectivity and high accuracy of the segmentation results.

The application relates to the technical field of integrated circuit design, in particular to a resource-friendly anisotropic filtering system. The system performs lightweight format conversion on an initial anisotropic ratio and an initial long axis length to obtain a reference anisotropic ratio and a reference long axis length, so that the storage bandwidth, operation units and other resources of a GPU chip are as low as possible under the premise of meeting the anisotropic filtering level calculation accuracy, thereby reducing the consumption of hardware resources of the GPU chip and improving the efficiency of anisotropic filtering level calculation.

When sampling a 3D texture using anisotropic filtering, an anisotropy direction along which to take samples in the texture is determined by determining reduced precision representations of the texture coordinate derivative vectors and using the reduced precision texture coordinate derivative vectors to determine a pair of vectors representing the directions of x and y axes for a 2D coordinate system on the plane in the 3D texture defined by the texture coordinate derivative vectors. The x and y axis vectors are used together with the texture coordinate derivative vectors to determine both a X-axis component and a Y-axis component for projected representations of the texture coordinate derivative vectors in the 2D coordinate system on the plane in the 3D texture defined by the texture coordinate derivative vectors. The projected representations of the texture coordinate derivative vectors are then used to determine the anisotropy direction.