Patents by Inventor Risheng LIU

Risheng LIU has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11948333
    Abstract: A disparity image fusion method for multiband stereo cameras belongs to the field of image processing and computer vision. The method obtains pixel disparity confidence information by using the intermediate output of binocular disparity estimation. The confidence information can be used to judge the disparity credibility of the position and assist disparity fusion. The confidence acquisition process makes full use of the intermediate output of calculation, and can be conveniently embedded into the traditional disparity estimation process, with high calculation efficiency and simple and easy operation. In the disparity image fusion method for multiband stereo cameras proposed by the method, the disparity diagrams participating in the fusion are obtained according to the binocular images of the corresponding bands, which makes full use of the information of each band and simultaneously avoiding introducing uncertainty and errors.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: April 2, 2024
    Assignees: DALIAN UNIVERSITY OF TECHNOLOGY, PENG CHENG LABORATORY
    Inventors: Wei Zhong, Hong Zhang, Haojie Li, Zhihui Wang, Risheng Liu, Xin Fan, Zhongxuan Luo, Shengquan Li
  • Patent number: 11908152
    Abstract: The present invention belongs to the field of image processing and computer vision, and discloses an acceleration method of depth estimation for multiband stereo cameras. In the process of depth estimation, during binocular stereo matching in each band, through compression of matched images, on one hand, disparity equipotential errors caused by binocular image correction can be offset to make the matching more accurate, and on the other hand, calculation overhead is reduced. In addition, before cost aggregation, cost diagrams are transversely compressed and sparsely matched, thereby reducing the calculation overhead again. Disparity diagrams obtained under different modes are fused to obtain all-weather, more complete and more accurate depth information.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: February 20, 2024
    Assignees: DALIAN UNIVERSITY OF TECHNOLOGY, PENG CHENG LABORATORY
    Inventors: Wei Zhong, Hong Zhang, Haojie Li, Zhihui Wang, Risheng Liu, Xin Fan, Zhongxuan Luo, Shengquan Li
  • Patent number: 11900634
    Abstract: The present invention discloses a method for adaptively detecting chessboard sub-pixel level corner points. Adaptive detection of chessboard sub-pixel level corner points is completed by marking position of an initial unit grid on a chessboard, using a homography matrix H calculated by pixel coordinates of four corner points of the initial unit grid in a pixel coordinate system and world coordinates in a world coordinate system to expand outwards, adaptively adjusting size of an iteration window in the process of expanding outwards, and finally spreading to the whole chessboard region.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: February 13, 2024
    Assignees: DALIAN UNIVERSITY OF TECHNOLOGY, PENG CHENG LABORATORY
    Inventors: Wei Zhong, Deyun Lv, Weiqiang Kong, Risheng Liu, Xin Fan, Zhongxuan Luo, Shengquan Li
  • Patent number: 11830222
    Abstract: The present invention proposes a bi-level optimization-based infrared and visible light fusion method, adopts a pair of infrared camera and visible light camera to acquire images, and relates to the construction of a bi-level paradigm infrared and visible light image fusion algorithm, which is an infrared and visible light fusion algorithm using mathematical modeling. Binocular cameras and NVIDIA TX2 are used to construct a high-performance computing platform and to construct a high-performance solving algorithm to obtain a high-quality infrared and visible light fusion image. The system is easy to construct, and the input data can be acquired by using stereo binocular infrared and visible light cameras respectively; the program is simple and easy to implement; and the fusion image is divided into an image domain and a gradient domain for fusion by means of mathematical modeling according to different imaging principles of infrared and visible light cameras.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: November 28, 2023
    Assignee: DALIAN UNIVERSITY OF TECHNOLOGY
    Inventors: Risheng Liu, Xin Fan, Jinyuan Liu, Wei Zhong, Zhongxuan Luo
  • Patent number: 11823363
    Abstract: The present invention provides an infrared and visible light fusion method, and belongs to the field of image processing and computer vision. The present invention adopts a pair of infrared binocular camera and visible light binocular camera to acquire images, relates to the construction of a fusion image pyramid and a significant vision enhancement algorithm, and is an infrared and visible light fusion algorithm using multi-scale transform. The present invention uses the binocular cameras and NVIDIATX2 to construct a high-performance computing platform and to construct a high-performance solving algorithm to obtain a high-quality infrared and visible light fusion image. The present invention constructs an image pyramid by designing a filtering template according to different imaging principles of infrared and visible light cameras, obtains image information at different scales, performs image super-resolution and significant enhancement, and finally achieves real-time performance through GPU acceleration.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: November 21, 2023
    Assignee: DALIAN UNIVERSITY OF TECHNOLOGY
    Inventors: Risheng Liu, Xin Fan, Jinyuan Liu, Wei Zhong, Zhongxuan Luo
  • Patent number: 11783457
    Abstract: A multispectral camera dynamic stereo calibration algorithm is based on saliency features. The joint self-calibration method comprises the following steps: step 1: conducting de-distortion and binocular correction on an original image according to internal parameters and original external parameters of an infrared camera and a visible light camera. Step 2: Detecting the saliency of the infrared image and the visible light image respectively based on a histogram contrast method. Step 3: Extracting feature points on the infrared image and the visible light image. Step 4: Matching the feature points extracted in the previous step. Step 5: judging a feature point coverage area. Step 6: correcting the calibration result. The present invention solves the change of a positional relationship between an infrared camera and a visible light camera due to factors such as temperature, humidity and vibration.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: October 10, 2023
    Assignee: DALIAN UNIVERSITY OF TECHNOLOGY
    Inventors: Wei Zhong, Haojie Li, Boqian Liu, Zhihui Wang, Risheng Liu, Zhongxuan Luo, Xin Fan
  • Patent number: 11783446
    Abstract: The present invention discloses a large-field-angle image real-time stitching method based on calibration. First, a calibration algorithm is used to solve the positional relationship between cameras, and the prior information is used to solve a homography matrix between images. The system is easy to build, and the program is simple and easy to implement; an overlapping area ROI of images can be calculated by the homography matrix between images, and an energy model thereof can be built and solved with a graph cut algorithm; the graph cut algorithm has high time complexity and depends on the number of nodes in a graph; here, images are divided into layers, and solutions are obtained layer by layer and iterated; and finally, a stitched image is further optimized by simple linear fusion of stitching seams and histogram equalization of the stitched image.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: October 10, 2023
    Assignee: DALIAN UNIVERSITY OF TECHNOLOGY
    Inventors: Wei Zhong, Yuankai Xiang, Haojie Li, Zhihui Wang, Risheng Liu, Xin Fan, Zhongxuan Luo
  • Patent number: 11783502
    Abstract: The present invention relates to the technical field of digital image processing, and provides an ellipse detection acceleration method based on generalized Pascal mapping. The method comprises: step 100, extracting accurate edge points from a real image by means an edge detection method of an ellipse detection method, connecting edge points into arcs, and taking a de-noised arc set as input of an ellipse detection acceleration method; step 200, screening out a valid candidate arc combinations probably belonging to the same ellipse from the arc set input in step 100; step 300, calculating five parameters of a candidate ellipse; repeating step 200 to step 300 until all valid candidate arc combinations in the arc set and corresponding candidate ellipses are found; and step 400, clustering and verifying candidate ellipse sets, obtaining a final detected ellipse set.
    Type: Grant
    Filed: March 5, 2021
    Date of Patent: October 10, 2023
    Assignee: DALIAN UNIVERSITY OF TECHNOLOGY
    Inventors: Qi Jia, Xin Fan, Zhongxuan Luo, Yu Liu, Qian Wang, Risheng Liu, Yi Wang, Xiujuan Xu
  • Patent number: 11575873
    Abstract: The present invention discloses a multispectral stereo camera self-calibration algorithm based on track feature registration, and belongs to the field of image processing and computer vision. Optimal matching points are obtained by extracting and matching motion tracks of objects, and external parameters are corrected accordingly. Compared with an ordinary method, the present invention uses the tracks of moving objects as the features required for self-calibration. The advantage of using the tracks is good cross-modal robustness. In addition, direct matching of the tracks also saves the steps of extraction and matching the feature points, thereby achieving the advantages of simple operation and accurate results.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: February 7, 2023
    Assignee: DALIAN UNIVERSITY OF TECHNOLOGY
    Inventors: Wei Zhong, Haojie Li, Boqian Liu, Zhihui Wang, Risheng Liu, Zhongxuan Luo, Xin Fan
  • Publication number: 20220335639
    Abstract: The present invention relates to the technical field of digital image processing, and provides an ellipse detection acceleration method based on generalized Pascal mapping. The method comprises: step 100, extracting accurate edge points from a real image by means an edge detection method of an ellipse detection method, connecting edge points into arcs, and taking a de-noised arc set as input of an ellipse detection acceleration method; step 200, screening out a valid candidate arc combinations probably belonging to the same ellipse from the arc set input in step 100; step 300, calculating five parameters of a candidate ellipse; repeating step 200 to step 300 until all valid candidate arc combinations in the arc set and corresponding candidate ellipses are found; and step 400, clustering and verifying candidate ellipse sets, obtaining a final detected ellipse set.
    Type: Application
    Filed: March 5, 2021
    Publication date: October 20, 2022
    Inventors: Qi JIA, Xin FAN, Zhongxuan LUO, Yu LIU, Qian WANG, Risheng LIU, Yi WANG, Xiujuan XU
  • Patent number: 11398053
    Abstract: The present invention discloses a multispectral camera external parameter self-calibration algorithm based on edge features, and belongs to the field of image processing and computer vision. Because a visible light camera and an infrared camera belong to different modes, fewer satisfactory point pairs are obtained by directly extracting and matching feature points. In order to solve the problem, the method starts from the edge features, and finds an optimal corresponding position of an infrared image on a visible light image through edge extraction and matching. In this way, a search range is reduced and the number of the satisfactory matched point pairs is increased, thereby more effectively conducting joint self-calibration on the infrared camera and the visible light camera. The operation is simple and results are accurate.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: July 26, 2022
    Assignee: DALIAN UNIVERSITY OF TECHNOLOGY
    Inventors: Wei Zhong, Boqian Liu, Haojie Li, Zhihui Wang, Risheng Liu, Xin Fan, Zhongxuan Luo
  • Publication number: 20220215569
    Abstract: The present invention belongs to the field of image processing and computer vision, and discloses an acceleration method of depth estimation for multiband stereo cameras. In the process of depth estimation, during binocular stereo matching in each band, through compression of matched images, on one hand, disparity equipotential errors caused by binocular image correction can be offset to make the matching more accurate, and on the other hand, calculation overhead is reduced. In addition, before cost aggregation, cost diagrams are transversely compressed and sparsely matched, thereby reducing the calculation overhead again. Disparity diagrams obtained under different modes are fused to obtain all-weather, more complete and more accurate depth information.
    Type: Application
    Filed: March 5, 2020
    Publication date: July 7, 2022
    Inventors: Wei ZHONG, Hong ZHANG, Haojie LI, Zhihui WANG, Risheng LIU, Xin FAN, Zhongxuan LUO, Shengquan LI
  • Publication number: 20220207776
    Abstract: A disparity image fusion method for multiband stereo cameras belongs to the field of image processing and computer vision. The method obtains pixel disparity confidence information by using the intermediate output of binocular disparity estimation. The confidence information can be used to judge the disparity credibility of the position and assist disparity fusion. The confidence acquisition process makes full use of the intermediate output of calculation, and can be conveniently embedded into the traditional disparity estimation process, with high calculation efficiency and simple and easy operation. In the disparity image fusion method for multiband stereo cameras proposed by the method, the disparity diagrams participating in the fusion are obtained according to the binocular images of the corresponding bands, which makes full use of the information of each band and simultaneously avoiding introducing uncertainty and errors.
    Type: Application
    Filed: March 5, 2020
    Publication date: June 30, 2022
    Inventors: Wei ZHONG, Hong ZHANG, Haojie LI, Zhihui WANG, Risheng LIU, Xin FAN, Zhongxuan LUO, Shengquan LI
  • Publication number: 20220198712
    Abstract: The present invention discloses a method for adaptively detecting chessboard sub-pixel level corner points. Adaptive detection of chessboard sub-pixel level corner points is completed by marking position of an initial unit grid on a chessboard, using a homography matrix H calculated by pixel coordinates of four corner points of the initial unit grid in a pixel coordinate system and world coordinates in a world coordinate system to expand outwards, adaptively adjusting size of an iteration window in the process of expanding outwards, and finally spreading to the whole chessboard region.
    Type: Application
    Filed: March 5, 2020
    Publication date: June 23, 2022
    Inventors: Wei ZHONG, Deyun LV, Weiqiang KONG, Risheng LIU, Xin FAN, Zhongxuan LUO, Shengquan LI
  • Publication number: 20220198694
    Abstract: The present invention discloses a disparity estimation optimization method based on upsampling and exact rematching, which conducts exact rematching within a small range in an optimized network, improves previous upsampling methods such as neighbor interpolation and bilinear interpolation for disparity maps or cost maps, and works out a propagation-based upsampling method by the way of network so that accurate disparity values can be better restored from disparity maps in the upsampling process.
    Type: Application
    Filed: March 5, 2020
    Publication date: June 23, 2022
    Inventors: Wei ZHONG, Hong ZHANG, Haojie LI, Zhihui WANG, Risheng LIU, Xin FAN, Zhongxuan LUO, Shengquan LI
  • Publication number: 20220174256
    Abstract: The present invention discloses a method for infrared small target detection based on a depth map in a complex scene, and belongs to the field of target detection. An infrared image is collected, the image is binarized by using priori knowledge of a to-be-detected target and adopting a pixel value method, the binary image is further limited based on deep priori knowledge, then static and dynamic scoring strategies are formulated to score a candidate connected component in the morphologically processed image, and an infrared small target in a complex scene is detected finally. The method can screen out targets within a specific range, has high reliability; has strong robustness; is simple in program and easy to implement, can be used in sea, land, and air, and has a significant advantage under a complex jungle background.
    Type: Application
    Filed: March 5, 2020
    Publication date: June 2, 2022
    Inventors: Weiqiang KONG, Deyun LV, Wei ZHONG, Risheng LIU, Xin FAN, Zhongxuan LUO
  • Patent number: 11350073
    Abstract: The present invention discloses a disparity image stitching and visualization method based on multiple pairs of binocular cameras. A calibration algorithm is used to solve the positional relationship between binocular cameras, and the prior information is used to solve a homography matrix between images; internal parameters and external parameters of the cameras are used to perform camera coordinate system transformation of depth images; the graph cut algorithm has high time complexity and depends on the number of nodes in a graph; the present invention divides the images into layers, and solutions are obtained layer by layer and iterated; then the homography matrix is used to perform image coordinate system transformation of the depth images, and a stitching seam is synthesized to realize seamless panoramic depth image stitching; and finally, depth information of a disparity image is superimposed on a visible light image.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: May 31, 2022
    Assignee: DALIAN UNIVERSITY OF TECHNOLOGY
    Inventors: Xin Fan, Risheng Liu, Zhuoxiao Li, Wei Zhong, Zhongxuan Luo
  • Publication number: 20220148213
    Abstract: The present invention discloses a method for fully automatically detecting chessboard corner points, and belongs to the field of image processing and computer vision. Full automatic detection of chessboard corner points is completed by setting one or a plurality of marks with colors or certain shapes on a chessboard to mark an initial position, shooting an image and conducting corresponding processing, using a homography matrix H calculated by initial pixel coordinates of a unit grid in a pixel coordinate system and manually set world coordinates in a world coordinate system to expand outwards, and finally spreading to the whole chessboard region.
    Type: Application
    Filed: March 5, 2020
    Publication date: May 12, 2022
    Inventors: Weiqiang KONG, Deyun LV, Wei ZHONG, Risheng LIU, Xin FAN, Zhongxuan LUO
  • Patent number: 11315273
    Abstract: The present invention discloses a disparity estimation method for weakly supervised trusted cost propagation, which utilizes a deep learning method to optimize the initial cost obtained by the traditional method. By combining and making full use of respective advantages, the problems of false matching and difficult matching of untextured regions in the traditional method are solved, and the method for weakly supervised trusted cost propagation avoids the problem of data label dependency of the deep learning method.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: April 26, 2022
    Assignees: DALIAN UNIVERSITY OF TECHNOLOGY, PENG CHENG LABORATORY
    Inventors: Wei Zhong, Hong Zhang, Haojie Li, Zhihui Wang, Risheng Liu, Xin Fan, Zhongxuan Luo, Shengquan Li
  • Patent number: 11315318
    Abstract: The present invention discloses a method for constructing a grid map by using a binocular stereo camera. A high-performance computing platform is constructed by using a binocular camera and a GPU, and a high-performance solving algorithm is constructed to obtain a high-quality grid map containing three-dimensional information. The system in the present invention is easy to construct, so the input data may be collected by using the binocular stereo camera; the program is simple and easy to implement. According to the present invention, the grid height is calculated by using spatial prior information and statistical knowledge, so that a three-dimensional result is more robust; and according to the present invention, the adaptive threshold of grids is solved by using spatial geometry, filtering and screening of the grids are completed, and thus the generalization ability and robustness of the algorithm are improved.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: April 26, 2022
    Assignee: DALIAN UNIVERSITY OF TECHNOLOGY
    Inventors: Wei Zhong, Shenglun Chen, Haojie Li, Zhihui Wang, Risheng Liu, Xin Fan, Zhongxuan Luo