公开(公告)号：US11962786B2

公开(公告)日：2024-04-16

申请号：US17671512

申请日：2022-02-14

Applicant: Apple Inc.

Inventor： Krishnakanth Rapaka ,  Alexandros Tourapis ,  David William Singer

IPC: H04N19/176 ,  H04N19/103 ,  H04N19/119 ,  H04N19/124 ,  H04N19/136 ,  H04N19/159 ,  H04N19/50

CPC classification number: H04N19/176 ,  H04N19/103 ,  H04N19/119 ,  H04N19/124 ,  H04N19/136 ,  H04N19/159 ,  H04N19/50

Abstract: A multi-stage coding method includes receiving an input block of data for encoding and one or more previously coded samples associated with the input block. The input block is segmented into at least a first sub-region and a second sub-region. A prediction for the first sub-region is generated based on the one or more previously coded samples. Residual data for the first sub-region is obtained using the prediction for the first sub-region. A reconstruction of the first sub-region is generated using the residual data for the first sub-region and the prediction for the first sub-region. A prediction for the second sub-region is generated using the reconstruction of the first sub-region. Residual data for the second sub-region is obtained using the prediction for the second sub-region. The input block is encoded based in part on the residual data for the first region and the residual data for the second region.

公开(公告)号：US11936867B2

公开(公告)日：2024-03-19

申请号：US17234596

申请日：2021-04-19

Applicant: Apple Inc.

Inventor： Krishnakanth Rapaka ,  Jaehong Chon ,  Alexandros Tourapis ,  David W. Singer

IPC: H04N19/124 ,  H04N19/172 ,  H04N19/186 ,  H04N19/82

CPC classification number: H04N19/124 ,  H04N19/172 ,  H04N19/186 ,  H04N19/82

Abstract: Improved video coding and decoding techniques are described, including techniques to derive quantization step sizes adaptively with quantization step size table templates. Quantization techniques described provide finer-grained control over quantization with a more flexible quantization step size especially at higher degrees of quantization. This may result in improved overall compression quality. Other coding parameters, such as in-loop filtering parameters, may be derived based on the more flexible quantization parameters.

公开(公告)号：US11895307B2

公开(公告)日：2024-02-06

申请号：US17062446

申请日：2020-10-02

Applicant: Apple Inc.

Inventor： Khaled Mammou ,  David Flynn ,  Alexandros Tourapis ,  Jungsun Kim

IPC: H04N7/12 ,  H04N19/20 ,  H04N19/119 ,  H04N19/124 ,  H04N19/61 ,  H04N19/176 ,  H04N19/50 ,  H04N19/136 ,  G06T9/00 ,  H04N19/12 ,  H04N19/189 ,  H04N19/64 ,  G06T9/40

CPC classification number: H04N19/20 ,  G06T9/001 ,  G06T9/40 ,  H04N19/119 ,  H04N19/12 ,  H04N19/124 ,  H04N19/136 ,  H04N19/176 ,  H04N19/189 ,  H04N19/50 ,  H04N19/61 ,  H04N19/647

Abstract: An encoder is configured to compress point cloud information using a blocks of nodes determined from a prediction tree. A prediction tree is generated for a point cloud. Segments of the prediction tree are identified. The segments are divided into blocks that are predicted by predecessor blocks within the segments. The blocks of the prediction tree may then be encoded and may be provided for transmission to a decoder that can regenerate the point cloud from the blocks of the prediction tree.

公开(公告)号：US11863738B2

公开(公告)日：2024-01-02

申请号：US17540356

申请日：2021-12-02

Applicant: Apple Inc.

Inventor： Alexandros Tourapis ,  Jungsun Kim ,  Krishnakanth Rapaka ,  David W. Singer

IPC: H04N19/105 ,  H04N19/172 ,  H04N19/174 ,  H04N19/184 ,  H04N19/513 ,  H04N19/70

CPC classification number: H04N19/105 ,  H04N19/172 ,  H04N19/174 ,  H04N19/184 ,  H04N19/513 ,  H04N19/70

Abstract: Techniques for encoding video with motion compensation include a compressed bitstream syntax that includes a list of all motion prediction reference frames without distinguishing between short-term reference frame and long-term reference frames. The list of reference frames may be provided in a slice header and may apply to encoded data video data within the corresponding slice. The list may be prefaced with a single number indicating the total number of reference frames. In an aspect delta POC reference numbers may be encoded with a flag indicating the sign of the delta POC when the absolute value of the POC is not equal to zero. In another aspect, a flag may be encoded for every reference frame indicating if POC information should be used when scaling prediction references, and a weighting parameter may be included when POC information should be used.

公开(公告)号：US20230403396A1

公开(公告)日：2023-12-14

申请号：US18239644

申请日：2023-08-29

Applicant: Apple Inc.

Inventor： Alexandros Tourapis ,  Guy Cote

IPC: H04N19/124 ,  H04N19/61 ,  H04N19/157 ,  H04N19/30 ,  H04N19/159 ,  H04N19/136 ,  H04N19/13 ,  H04N19/15 ,  H04N19/70 ,  H04N19/126 ,  H04N19/186 ,  H04N19/51 ,  H04N19/86

CPC classification number: H04N19/124 ,  H04N19/61 ,  H04N19/157 ,  H04N19/30 ,  H04N19/159 ,  H04N19/136 ,  H04N19/13 ,  H04N19/15 ,  H04N19/70 ,  H04N19/126 ,  H04N19/186 ,  H04N19/51 ,  H04N19/86 ,  H04N19/172

Abstract: A method of signaling additional chroma QP offset values that are specific to quantization groups is provided, in which each quantization group explicitly specifies its own set of chroma QP offset values. Alternatively, a table of possible sets of chroma QP offset values is specified in the header area of the picture, and each quantization group uses an index to select an entry from the table for determining its own set of chroma QP offset values. The quantization group specific chroma QP offset values are then used to determine the chroma QP values for blocks within the quantization group in addition to chroma QP offset values already specified for higher levels of the video coding hierarchy.

公开(公告)号：US11818401B2

公开(公告)日：2023-11-14

申请号：US17718647

申请日：2022-04-12

Applicant: Apple Inc.

Inventor： Alexandros Tourapis ,  Jungsun Kim ,  Valery G. Valentin ,  Fabrice A. Robinet ,  Yeping Su ,  Khaled Mammou

IPC: H04N19/96 ,  G06T9/00 ,  H04N19/176 ,  H04N19/91 ,  G06T17/00

CPC classification number: H04N19/96 ,  G06T9/00 ,  G06T17/005 ,  H04N19/176 ,  H04N19/91

Abstract: An encoder is configured to compress point cloud geometry information using an octree geometric compression technique that utilizes a binary arithmetic encoder, a look-ahead table, a cache, and a context selection process, wherein encoding contexts are selected based, at least in part, on neighborhood configurations. In a similar manner, a decoder is configured to decode compressed point cloud geometry information utilizing a binary arithmetic encoder, a look-ahead table, a cache, and a context selection process.

公开(公告)号：US11798196B2

公开(公告)日：2023-10-24

申请号：US17145205

申请日：2021-01-08

Applicant: Apple Inc.

Inventor： Jungsun Kim ,  Khaled Mammou ,  Alexandros Tourapis

IPC: G06T9/00 ,  G06T17/20 ,  G06T3/40

CPC classification number: G06T9/001 ,  G06T3/40 ,  G06T17/20 ,  G06T2210/12

Abstract: A system comprises an encoder configured to compress attribute information and/or spatial information for three-dimensional (3D) visual volumetric content and/or a decoder configured to decompress compressed attribute and/or spatial information for the 3D visual volumetric content. The encoder is configured to convert 3D visual volumetric content, such as a point cloud or mesh, into image based patch representations. The encoder is further configured to select one or more reference patches for copying or prediction, such that metadata for copying or predicting a patch based on the reference patch is signaled without explicitly signaling a full set of information for the copied or predicted patch. Likewise, a decoder is configured to receive such information and reconstruct a 3D version of the 3D visual volumetric content using both signaled and predicted or copied patches.

公开(公告)号：US20230290009A1

公开(公告)日：2023-09-14

申请号：US18166154

申请日：2023-02-08

Applicant: Apple Inc.

Inventor： Khaled Mammou ,  Alexandros Tourapis ,  Jungsun Kim

IPC: G06T9/00 ,  G06T17/20

CPC classification number: G06T9/001 ,  G06T17/205

Abstract: A re-meshing pre-processor for re-meshing a 3D textured mesh M(i) to generate a base mesh m(i) and displacement field d(i) for input into a mesh encoder, can include a Mesh Decimation module that includes processing hardware that reduces the number of vertices or faces of input mesh M(i), or a mesh derived therefrom, while substantially preserving the shape of the input mesh M(i), thereby producing a decimated mesh dm(i) and a projected mesh P(i); and a Fitting Subdivision Surface module that includes processing hardware that processes the input mesh M(i), the decimated mesh dm(i) or a mesh derived therefrom, and the projected mesh P(i) to produce a base mesh m(i) and the displacement field d(i) for input into a mesh encoder.

公开(公告)号：US20230290008A1

公开(公告)日：2023-09-14

申请号：US18166148

申请日：2023-02-08

Applicant: Apple Inc.

Inventor： Khaled Mammou ,  Alexandros Tourapis ,  Jungsun Kim

IPC: G06T9/00 ,  G06T17/20

CPC classification number: G06T9/001 ,  G06T17/205

Abstract: A method of compressing a 3D textured mesh M(i), the 3D textured mesh being defined by connectivity C(i), geometry G(i), texture coordinates T(i), and texture connectivity CT(i), wherein the mesh is associated with one or more 2D image attribute maps A(i) describing attributes associated with the mesh surface, can include pre-processing 3D textured mesh M(i) and attribute maps A(i) to generate a base mesh m(i) and displacement field d(i); and processing 3D textured mesh M(i), attribute maps A(i), base mesh m(i), and the displacement field d(i) to generate a compressed bitstream b(i).

公开(公告)号：US11711527B2

公开(公告)日：2023-07-25

申请号：US17404452

申请日：2021-08-17

Applicant: Apple Inc.

Inventor： Alexandros Tourapis ,  Yeping Su ,  David W. Singer ,  Hsi-Jung Wu

IPC: H04N19/186 ,  H04N19/189 ,  H04N9/64 ,  H04N11/20 ,  H04N19/70 ,  H04N19/46 ,  H04N19/117 ,  H04N19/132 ,  H04N19/154 ,  H04N19/59 ,  H04N9/67 ,  H04N19/82 ,  H04N19/147 ,  H04N19/80 ,  H04N19/85 ,  H04N19/44

CPC classification number: H04N19/186 ,  H04N9/64 ,  H04N9/67 ,  H04N11/20 ,  H04N19/117 ,  H04N19/132 ,  H04N19/147 ,  H04N19/154 ,  H04N19/189 ,  H04N19/44 ,  H04N19/46 ,  H04N19/59 ,  H04N19/70 ,  H04N19/80 ,  H04N19/82 ,  H04N19/85

Abstract: A method of adaptive chroma downsampling is presented. The method comprises converting a source image to a converted image in an output color format, applying a plurality of downsample filters to the converted image and estimating a distortion for each filter chose the filter that produces the minimum distortion. The distortion estimation includes applying an upsample filter, and a pixel is output based on the chosen filter. Methods for closed loop conversions are also presented.