Arris Enterprises LLC

Sony Corporation

Nokia Technologies Oy

Sony Electronics Inc

Seungwook Hong

Limin Wang

Krit Panusopone

Yue Yu

Sriram Sampathkumaran

Eric Yam

Abhishek Pramod Patil

Yang Yu

Aravind Asam

Dipendu Saha

Helmut Neumann

Aixin Liu

Xiangpeng Jing

Guru Prashanth Balasubramanian

Meeta Jain

Miska Matias Hannuksela

Jean-Pierre Simon Guillou

Djung N Nguyen

Tanmay Agnihotri

Andy Nguyen

Diung Nguyen

A method of partitioning in video coding for JVET, comprising representing a JVET coding tree unit as a root node in a quadtree plus binary tree (QTBT structure that can have quadtree or binary partitioning of the root node and quadtree or binary trees branching from each of the leaf nodes. The partitioning at any depth can use asymmetric binary partitioning to split a child node represented by a leaf node into two child coding units of unequal size, representing the two child coding units as leaf nodes in a binary tree branching from the parent leaf node and coding the child coding units represented by final leaf nodes of the binary tree with JVET. Disclosed is a generalized method of partitioning a block, either square or rectangular, which leads to more flexible block sizes with possible higher coding efficiency.

General block partitioning method

A method, apparatus, and computer program product provide for improving prediction accuracy of a geometric partitioning merge mode. In the context of a method, the method accesses a coding unit partitioned into a first partition and a second partition. The method also determines whether an enabling value associated with the coding unit is indicative of additional motion vector refinement and, in accordance with a determination that the enabling value associated with the coding unit is indicative of additional motion vector refinement, determines at least one motion vector difference value for at least one partition of the first partition and the second partition. The method additionally applies a prediction of the coding unit in accordance with the at least one motion vector difference value.

Geometric partitioning merge mode with merge mode with motion vector difference

A method, apparatus, and computer program product provide for management of luma mapping with chroma scaling (LMCS) processes for Gradual Decoding Refresh (GDR) pictures. In the context of a method, the method accesses a picture to be decoded and determines whether the picture is a GDR picture. The method can also prevent a LMCS decoding process from being applied to the GDR picture. Another method can determine whether a virtual boundary is within a current coding tree unit of the gradual decoding refresh picture and if so, prevent a chroma residual scaling decoding process associated with LMCS from being applied to one or more coding units within a clean area. Another method can pad a neighboring pixel area from one or more reconstructed pixels in a clean area for a chroma residual scaling decoding process associated with LMCS.

Luma mapping with chroma scaling for gradual decoding refresh

A method, apparatus, and computer program product provide for management of luma mapping with chroma scaling (LMCS) processes for Gradual Decoding Refresh (GDR) pictures. In the context of a method, the method accesses a picture to be decoded and determines whether the picture is within a GDR period. The method can also prevent a LMCS decoding process from being applied to the picture within the GDR period. Another method can determine whether a virtual boundary is within a current coding tree unit of a picture with a GDR period and if so, prevent a chroma residual scaling decoding process associated with LMCS from being applied to one or more coding units within a clean area. Another method can pad a neighboring pixel area from one or more reconstructed pixels in a clean area for a chroma residual scaling decoding process associated with LMCS.

A method of decoding JVET video includes receiving a bitstream indicating how a coding tree unit was partitioned into coding units, and parsing said bitstream to generate at least one predictor based on an intra prediction mode signaled in the bitstream. The predictor may be generated by interpolating neighboring pixels for each pixel within a coding block. The computation may be more accurate by deriving a value for a bottom right neighboring pixel.

Video bitstream coding

A method of decoding JVET video includes receiving a bitstream that includes encoded video data that includes encoded video data. From the encoded data, a horizontal predictor and a vertical predictor for a pixel in the current coding block may be interpolated. A coding block size may be identified to determine whether to use equal weight or unequal weights to apply to each of the horizontal and vertical predictors for calculating a final planar prediction value P(x,y) by comparing the coding block size to a coding block size threshold.

Adaptive unequal weight planar prediction

A system and method of planar motion vector derivation which, in some embodiments can employ an unequal weighted combination of adjacent motion vectors. In some embodiments, motion vector information associated with a bottom right pixel or block adjacent to a current coding unit can be derived from motion information associated with a top row or top neighboring row of a current coding unit and motion information associated with a left column or left neighboring column of a current coding unit. Weighted or non-weighted combinations of such values can be combined in a planar mode prediction model to derive associated motion information for bottom and/or right adjacent pixels or blocks.

Unequal weight planar motion vector derivation

A method, apparatus, and computer program product provide for management of history-based motion vector prediction (HMVP) processes for Gradual Decoding Refresh (GDR) pictures, as well as efficient implementations of mode selection within a GDR period and tuning of coding tools such as in-loop filters and Luma Mapping with Chroma Scaling (LMCS) such that current coding units within a clean area avoid use of coding information within a dirty area of a picture. In the context of a method, the method accesses a current coding unit of a picture. The method also accesses information associated with coding unit references each associated with a respective inter-coded coding unit. The method also determines at least one candidate coding unit reference based at least upon a comparison of an associated index value to a dirty index, and assigns at least one coding unit to a candidate list for selection in a coding process.

History-based motion vector prediction and mode selection for gradual decoding refresh

A system and method of defining a plane for planar coding in JVET in which first and second lines can be defined based upon pixels in left-adjacent and top-adjacent coding units. In some embodiments, the least squares method can be employed to define the relevant lines. One point along each of the lines can then be identified and the y-intercepts of the two lines can be averaged to obtain a third point. The three points can then be used to identify and define a plane for planar coding in JVET.

System and method for constructing a plane for planar prediction

A second level intra prediction mode can be combined with one or more of sixty-seven JVET intra prediction modes during encoding of a coding unit in a video bitstream. Embodiments include making a position dependent intra prediction combination (PDPC) mode available as the second level intra prediction mode. In embodiments, when a PDPC (position dependent intra prediction combination) mode is enabled, the second level intra prediction is combined with one of the 67 selected intra predictor modes. In embodiments, the PDPC mode is only enabled or available for a predetermined subset of intra prediction modes (out of 67 possible modes), in order to reduce encoder complexity and potentially improve coding efficiency. The PDPC mode may be identifies as enabled or available by a list of modes or signaling in the video bitstream.

Constrained position dependent intra prediction combination (PDPC)

A method, apparatus, and computer program product provide for solving merge candidate list mismatches. In the context of a method, the method accesses a current coding unit of a picture. The method can also generate a merge candidate list comprising a plurality of coding unit representations in a predefined order. The method also determines whether a particular coding unit representation within the merge candidate list is representative of a coding unit within a dirty area of the picture and prevents the particular coding unit representation and one or more coding unit representations following the particular coding unit in the predefined order from being selected as a merge candidate for the current coding unit.

Merge candidate list for gradual decoding refresh

A method, apparatus and a non-transitory computer readable medium are provided for receiving an input picture divided into a plurality of coding units (CUs) and comprising a virtual boundaries between a dirty area and a clean area of the input picture, each CU located within either the clean area or the dirty area. The virtual boundary is treated as a picture boundary for coding units within the clean area and as a non-boundary for coding units within the dirty area. For a current CU, a history-based motion vector prediction (HMVP) table can be prepared that identifies other CUs as HMVP candidates for inter prediction, the HMVP candidates being adjacent the current CU. The HMVP candidate CUs are limited to CUs previously coded in the clean area. The current CU can be intra coded based at least upon the HMVP candidates from the HMVP table.

Method, apparatus, and computer program product for gradual decoding refresh for video encoding and decoding

A method of decoding JVET video includes receiving a bitstream and calculating a final planar prediction in planar mode to predict pixel values for a current coding block. The final planar prediction may rely on using unequal weights applied to each of a horizontal and vertical predictor, where such predictors may be generated by interpolating neighboring pixels for each predicted pixel within a coding block. The computation may be made more accurate by deriving a value for a bottom right neighboring pixel.

Unequal weight planar prediction

A method of partitioning in video coding for JVET, comprising representing a JVET coding tree unit as a root node in a quadtree plus binary tree (QTBT) structure that can have quadtree or binary partitioning of the root node and quadtree or binary trees branching from each of the leaf nodes. The partitioning at any depth can use asymmetric binary partitioning to split a node represented by a leaf node into two child nodes of unequal size, representing the two child nodes as leaf nodes in a binary tree branching from the parent leaf node and coding the child nodes represented by final leaf nodes of the binary tree with JVET, wherein further partitioning of child nodes split from leaf nodes via asymmetric binary partitioning is allowed recursively along the same branch in any order with symmetric partitioning.

JVET quadtree plus binary tree (QTBT) structure with multiple asymmetrical partitioning

An improved method for temporal motion vector prediction for inter block HEVC is provided that relies on a block translational model. The method adds an offset to a temporal motion vector predictor (TMVP) to improve prediction accuracy. The method first designates a current prediction block as an area for motion compensation where all the pixels inside the prediction block perform identical translation temporally using motion vectors MVs. A coordinate offset is then derived for a current prediction block from the MVs of its spatially neighboring blocks. The offset TMVP is then defined for the current prediction block as the MV of an offset block which is in the geometrical location of the current prediction block coordinate plus the coordinate offset in a specified temporal reference picture. The offset TMVP is then used to code MVs.

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San Diego, CA, United States of America

Seungwook Hong