公开(公告)号：US12143605B2

公开(公告)日：2024-11-12

申请号：US17543126

申请日：2021-12-06

Applicant: Google LLC

Inventor： Rohit Singh ,  Debargha Mukherjee ,  Elliott Karpilovsky ,  Lester Lu

IPC: H04N19/184 ,  H04N19/124 ,  H04N19/61

Abstract: Transform modes are derived for inter-predicted blocks using side information. A prediction residual is generated for a current video block using a reference frame. Side information associated with one or both of the current video block or the reference frame is identified. A trained transform is determined from amongst multiple trained transforms based on the side information, in which each of the trained transforms is determined using individual side information types and combinations of the individual side information types and the side information represents values of one of the individual side information types or one of the combinations of the individual side information types. The prediction residual is transformed according to the trained transform, and data associated with the transformed prediction residual and the side information are encoded to a bitstream.

公开(公告)号：US20250047833A1

公开(公告)日：2025-02-06

申请号：US18717407

申请日：2022-12-07

Applicant: Google LLC

Inventor： Sarah Parker ,  Debargha Mukherjee ,  Lester Lu

IPC: H04N19/105 ,  H04N19/157 ,  H04N19/176 ,  H04N19/503 ,  H04N19/70

Abstract: A new reference framework is described that ranks reference frames based on a normative procedure (e.g., a calculated score) and signals the reference frames based on their ranks. The bitstream syntax is simplified by using a context tree that relies on the ranking. Moreover, mapping reference frames to buffers does not have to be signaled and can be determined at the decoder. In an example, the identifier of a reference frame used to code a current block can include identifying a syntax element corresponding to the identifier, determining context information for the syntax element, determining a node of a context tree that includes the syntax element, and coding the syntax element according to a probability model using the context information associated with the node. The context tree is a binary tree that includes, as nodes, the available reference frames arranged in the ranking.

公开(公告)号：US20210185312A1

公开(公告)日：2021-06-17

申请号：US16712057

申请日：2019-12-12

Applicant: GOOGLE LLC

Inventor： Lester Lu ,  Debargha Mukherjee ,  Elliott Karpilovsky

IPC: H04N19/107 ,  H04N19/122 ,  H04N19/50 ,  H04N19/176

Abstract: Coding a block of video data includes determining a prediction mode for the block, which is an inter-prediction or intra-prediction mode, determining a transform type for the block, and coding the block using the prediction mode and the transform type. The transform type is one of a first plurality of transform types when the prediction mode is the inter-prediction mode, and is one of a second plurality of transform types when the prediction mode is the intra-prediction mode. The first plurality of transform types includes first fixed transform types and first mode-dependent transform types that are based on a first learned transform generated using inter-predicted blocks. The second plurality of transform types includes second fixed transform types and second mode-dependent transform types that are based on a second learned transform generated using intra-predicted blocks. The first and second fixed transform types have at least some fixed transform types in common.

公开(公告)号：US20220094950A1

公开(公告)日：2022-03-24

申请号：US17543126

申请日：2021-12-06

Applicant: Google LLC

Inventor： Rohit Singh ,  Debargha Mukherjee ,  Elliott Karpilovsky ,  Lester Lu

IPC: H04N19/184 ,  H04N19/124 ,  H04N19/61

Abstract: Transform modes are derived for inter-predicted blocks using side information. A prediction residual is generated for a current video block using a reference frame. Side information associated with one or both of the current video block or the reference frame is identified. A trained transform is determined from amongst multiple trained transforms based on the side information, in which each of the trained transforms is determined using individual side information types and combinations of the individual side information types and the side information represents values of one of the individual side information types or one of the combinations of the individual side information types. The prediction residual is transformed according to the trained transform, and data associated with the transformed prediction residual and the side information are encoded to a bitstream.

公开(公告)号：US11284071B2

公开(公告)日：2022-03-22

申请号：US16712057

申请日：2019-12-12

Applicant: GOOGLE LLC

Inventor： Lester Lu ,  Debargha Mukherjee ,  Elliott Karpilovsky

IPC: H04N19/107 ,  H04N19/122 ,  H04N19/176 ,  H04N19/50

Abstract: Coding a block of video data includes determining a prediction mode for the block, which is an inter-prediction or intra-prediction mode, determining a transform type for the block, and coding the block using the prediction mode and the transform type. The transform type is one of a first plurality of transform types when the prediction mode is the inter-prediction mode, and is one of a second plurality of transform types when the prediction mode is the intra-prediction mode. The first plurality of transform types includes first fixed transform types and first mode-dependent transform types that are based on a first learned transform generated using inter-predicted blocks. The second plurality of transform types includes second fixed transform types and second mode-dependent transform types that are based on a second learned transform generated using intra-predicted blocks. The first and second fixed transform types have at least some fixed transform types in common.

公开(公告)号：US12003706B2

公开(公告)日：2024-06-04

申请号：US17700298

申请日：2022-03-21

Applicant: Google LLC

Inventor： Lester Lu ,  Debargha Mukherjee ,  Elliott Karpilovsky

IPC: H04N19/107 ,  H04N19/122 ,  H04N19/176 ,  H04N19/50

CPC classification number: H04N19/107 ,  H04N19/122 ,  H04N19/176 ,  H04N19/50

Abstract: Decoding video data includes, for a block encoded using a prediction mode, determining a transform mode for the block using the prediction mode. The transform mode is a first mode when the prediction mode is an inter-prediction mode and is a second mode when the prediction mode is an intra-prediction mode. The first mode is an available first transform type that is a combination of transforms selected from first fixed transforms and first learned transforms that each comprise a respective transformation matrix generated iteratively using blocks predicted using the inter-prediction mode. The second mode is an available second transform type that is a combination of transforms selected from second fixed transforms, which is a proper subset of the first fixed transforms, and a second learned transform comprising a transformation matrix that is generated iteratively using blocks predicted using the intra-prediction mode. Decoding the block uses the prediction and transform modes.

公开(公告)号：US20230011893A1

公开(公告)日：2023-01-12

申请号：US17779692

申请日：2019-12-23

Applicant: Google LLC

Inventor： Debargha Mukherjee ,  Lester Lu ,  Elliott Karpilovsky

IPC: H04N19/126 ,  H04N19/176 ,  H04N19/463 ,  H04N19/12 ,  H04N19/60 ,  H04N19/119 ,  H04N19/42

Abstract: Residual coding using vector quantization (VQ) is described. A flag indicating whether a residual block for the current block is encoded using VQ. In response to the flag indicating that the residual block is encoded using VQ, a parameter indicating an entry in a codebook is decoded, and the residual block is decoded using the entry. In response to the flag indicating that the residual block is not encoded using VQ, the residual block is decoded based on a skip flag indicating whether the current block is encoded using transform skip. The current block is reconstructed using the residual block.

公开(公告)号：US20220217336A1

公开(公告)日：2022-07-07

申请号：US17700298

申请日：2022-03-21

Applicant: Google LLC

Inventor： Lester Lu ,  Debargha Mukherjee ,  Elliott Karpilovsky

IPC: H04N19/107 ,  H04N19/122 ,  H04N19/176 ,  H04N19/50

Abstract: Decoding video data includes, for a block encoded using a prediction mode, determining a transform mode for the block using the prediction mode. The transform mode is a first mode when the prediction mode is an inter-prediction mode and is a second mode when the prediction mode is an intra-prediction mode. The first mode is an available first transform type that is a combination of transforms selected from first fixed transforms and first learned transforms that each comprise a respective transformation matrix generated iteratively using blocks predicted using the inter-prediction mode. The second mode is an available second transform type that is a combination of transforms selected from second fixed transforms, which is a proper subset of the first fixed transforms, and a second learned transform comprising a transformation matrix that is generated iteratively using blocks predicted using the intra-prediction mode. Decoding the block uses the prediction and transform modes.

公开(公告)号：US20250039436A1

公开(公告)日：2025-01-30

申请号：US18785699

申请日：2024-07-26

Applicant: GOOGLE LLC

Inventor： Lester Lu ,  Xiang Li ,  Debargha Mukherjee

IPC: H04N19/513 ,  H04N19/139 ,  H04N19/176 ,  H04N19/196

Abstract: Coding including dynamic range handling of high dimensional inverse autocorrelation in optical flow refinement includes obtaining a refinement model from available warped refinement models, wherein the available warped refinement models include a four-parameter scaling refinement model, a three-parameter scaling refinement model, and a four-parameter rotational refinement model, obtaining refined motion vectors using the warped refinement model and previously obtained reference frame data in the absence of data expressly indicating the refined motion vectors in the encoded bitstream, wherein obtaining the refined motion vectors includes using a dynamic range adjusted autocorrelation matrix, generating refined prediction block data using the refined motion vectors, generating reconstructed block data using the refined prediction block data, including the reconstructed block data in reconstructed frame data for the current frame, and outputting the reconstructed frame data.

公开(公告)号：US20240422309A1

公开(公告)日：2024-12-19

申请号：US18820598

申请日：2024-08-30

Applicant: GOOGLE LLC

Inventor： Lin Zheng ,  Yaowu Xu ,  Lester Lu ,  Jingning Han ,  Bohan Li

IPC: H04N19/105 ,  H04N19/139 ,  H04N19/172 ,  H04N19/573

Abstract: Methods, systems and apparatuses are disclosed including computer readable medium storing instructions used to encode or decode a video or a bitstream encodable or decodable using disclosed steps. The steps include reconstructing a first reference frame and a second reference frame for a current frame to be encoded or decoded, projecting motion vectors of the first reference frame and the second reference frame onto pixels of a current reference frame resulting in a first pixel in the current reference frame being associated with a plurality of projected motion vectors, and selecting a first projected motion vector from the plurality of projected motion vectors as a selected motion vector associated with the first pixel to be used for determining a pixel value of the first pixel, the selection based on magnitudes of the respective ones of the plurality of projected motion vectors.