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81 条记录 (耗时 0.022 秒)

    Hash-based attribute prediction for point cloud coding
    41.
    发明授权
    Hash-based attribute prediction for point cloud coding 有权

    公开(公告)号：US11580671B2

    公开(公告)日：2023-02-14

    申请号：US17317053

    申请日：2021-05-11

    申请人： TENCENT AMERICA LLC

    发明人： Xiang Zhang ,  Wen Gao ,  Shan Liu

    IPC分类号： H03M7/00 ,  G06T9/00 ,  H03M7/30

    摘要： A method, computer program, and computer system is provided for point cloud coding. Data corresponding to a point cloud is received. Hash elements corresponding to attribute values associated with the received data is reconstructed. A size of a hash table may be decreased based on deleting one or more of the hash elements corresponding to non-border regions associated with the attribute values. The data corresponding to the point cloud is decoded based on the reconstructed hash elements.

    Method of coding attributes for point cloud coding
    42.
    发明授权
    Method of coding attributes for point cloud coding 有权

    公开(公告)号：US11317117B2

    公开(公告)日：2022-04-26

    申请号：US17139177

    申请日：2020-12-31

    申请人： TENCENT AMERICA LLC

    发明人： Wen Gao ,  Xiang Zhang ,  Shan Liu

    IPC分类号： H04N19/597 ,  H04N19/124 ,  H04N19/159 ,  H04N19/147 ,  H04N19/119 ,  H04N19/70 ,  H04N19/136 ,  H04N19/103

    摘要： A method, a non-transitory computer readable medium, and a computer system is provided for encoding or decoding video data. The method may include: receiving an entropy coded bitstream comprising compressed video data including point cloud occupancy codes; generating one or more dequantized dimensions of a boundary box of a point cloud; based on determining that the compressed video data was predicted by using the attribute-based predictor, determining a predictor for decoding is the attribute-based predictor; based on determining that the compressed video data was predicted by using the attribute-based predictor, determining the predictor for decoding is the geometry-based predictor; and building an octree structure by using the determined predictor.

    Fast recolor for video based point cloud coding
    44.
    发明授权
    Fast recolor for video based point cloud coding 有权

    公开(公告)号：US12101505B2

    公开(公告)日：2024-09-24

    申请号：US17500345

    申请日：2021-10-13

    申请人： TENCENT AMERICA LLC

    发明人： Xiang Zhang ,  Wen Gao ,  Shan Liu ,  Weiwei Feng ,  Bing Jian

    IPC分类号： H04N19/597 ,  H04N19/186

    CPC分类号： H04N19/597 ,  H04N19/186

    摘要： Methods and apparatuses of encoding a video stream using video point cloud coding include obtaining a source point cloud; obtaining a geometry-reconstructed point cloud, wherein the geometry-reconstructed point cloud is reconstructed using lossy coding; obtaining a target point included in the geometry-reconstructed point cloud; performing at least one of a forward K-dimensional (KD)-tree search to determine a first plurality of points of the source point cloud which are nearest neighbors to the target point, and a backward KD-tree search to determine a second plurality of points of the source point cloud for which the target point is a nearest neighbor; determining an average color value based on at least one of a first average color value of the first plurality of points and a second average color value of the second plurality of points; selecting a color value for the target point based on the average color value; and generating an encoded video stream based on the selected color value.

    Image based sampling metric for quality assessment
    45.
    发明授权
    Image based sampling metric for quality assessment 有权

    公开(公告)号：US12100102B2

    公开(公告)日：2024-09-24

    申请号：US17862154

    申请日：2022-07-11

    申请人： Tencent America LLC

    发明人： Xiang Zhang ,  Chao Huang ,  Shan Liu

    IPC分类号： G06T17/05 ,  G06T19/20

    CPC分类号： G06T17/05 ,  G06T19/20

    摘要： Aspects of the disclosure provide methods and apparatuses of quality assessment for three dimensional (3D) graphics modeling. In some examples, an apparatus for quality assessment includes processing circuitry. The processing circuitry determines an updated virtual camera position in response to a position change of a virtual camera for projection from a three-dimensional (3D) space to a two-dimensional (2D) space. The processing circuitry projects a reference 3D representation according to the updated virtual camera position to generate a reference 2D image, and projects a 3D representation under assessment according to the updated virtual camera position to generate an assessment 2D image. The processing circuitry calculates an assessment score associated with the updated virtual camera position based on the reference 2D image and the assessment 2D image.

    Method and apparatus for Haar-based point cloud coding
    47.
    发明授权
    Method and apparatus for Haar-based point cloud coding 有权

    公开(公告)号：US12020461B2

    公开(公告)日：2024-06-25

    申请号：US17446263

    申请日：2021-08-27

    申请人： TENCENT AMERICA LLC

    发明人： Wen Gao ,  Xiang Zhang ,  Shan Liu

    IPC分类号： G06T9/40 ,  H04N19/60

    CPC分类号： G06T9/40 ,  H04N19/60 ,  G06T2210/56

    摘要： In a method of point cloud attribute decoding in a point cloud decoder, a sorting method of a set of points of a point is determined. A quantization parameter for quantizing transform coefficients of a Haar-based attribute coding of the point cloud is determined based on first signaling information in a coded bitstream of the point cloud. The Haar-based attribute coding is configured to perform point cloud compression on the set of points of the point cloud based on a Haar transform. An entropy decoding method for decoding the quantized transform coefficients is determined according to the quantization parameter that is determined based on the first signaling information. The quantized transform coefficients are further determined based on the entropy decoding method. Attributes of the point cloud are reconstructed based on the determined sorting method and the determined quantized transform coefficients.

    TEXTURE COORDINATE PREDICTION IN MESH COMPRESSION
    50.
    发明公开
    TEXTURE COORDINATE PREDICTION IN MESH COMPRESSION 审中-公开

    公开(公告)号：US20240078713A1

    公开(公告)日：2024-03-07

    申请号：US18345027

    申请日：2023-06-30

    申请人： Tencent America LLC

    发明人： Shan Liu ,  Jun Tian ,  Xiaozhong Xu ,  Chao Huang ,  Xiang Zhang

    IPC分类号： G06T9/00

    CPC分类号： G06T9/001

    摘要： Method, apparatus, and system for texture coordinate prediction for mesh compression are provided. The process may include receiving, for a mesh, a coordinate of a first vertex and a coordinate of a prediction candidate vertex in a three dimensional (3D) space. The process may include determining a stretch perpendicular distance associated with the first vertex and the prediction candidate vertex, the stretch perpendicular distance being based on a conversion of the 3D space into a two dimensional (2D) space, and determining a 2D texture coordinate of the first vertex based on the stretch perpendicular distance associated with the first vertex and the prediction candidate vertex. The process may also include determining a residual of a predicted coordinate of the first vertex and an actual 2D coordinate of the first vertex; and compressing the mesh based on entropy coding the residual.