A system and method of decoding a set of greatest coded line index values for a precinct of video data from a video bitstream, the precinct of video data including one or more subbands. The method comprises decoding a greatest coded line index prediction mode for each subband from the video bitstream; decoding a plurality of greatest coded line index delta values for each subband from the video bitstream using the greatest coded line index prediction mode for the subband; and producing the greatest coded line index values for each subband using the plurality of greatest coded line index delta values and the greatest coded line index prediction mode for the subband.

A method of decoding JVET video, comprising defining a coding unit (CU) template within a decoded area of a video frame, the CU template being positioned above and/or to the left of a current decoding position for which data was intra predicted, defining a search window within the decoded area, the search window being adjacent to the CU template, generating a plurality of candidate prediction templates based on pixel values in the search window, each of the plurality of candidate prediction templates being generated using different intra prediction modes, calculating a matching cost between the CU template and each of the plurality of candidate prediction templates, selecting an intra prediction mode that generated the candidate prediction template that had the lowest matching cost relative to the CU template, and generating a prediction CU for the current decoding position based on the intra prediction mode.

A method of decoding JVET video, comprising defining a coding unit (CU) template within a decoded area of a video frame, the CU template being positioned above and/or to the left of a current decoding position for which data was intra predicted, defining a search window within the decoded area, the search window being adjacent to the CU template, generating a plurality of candidate prediction templates based on pixel values in the search window, each of the plurality of candidate prediction templates being generated using different intra prediction modes, calculating a matching cost between the CU template and each of the plurality of candidate prediction templates, selecting an intra prediction mode that generated the candidate prediction template that had the lowest matching cost relative to the CU template, and generating a prediction CU for the current decoding position based on the intra prediction mode.

A method of partitioning a video coding block for JVET, comprising representing a JVET coding tree unit as a root node in a quadtree plus binary tree (QTBT) structure that can have a quadtree branching from the root node and binary trees branching from each of the quadtree's leaf nodes using asymmetric binary partitioning to split a coding unit represented by a quadtree 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 quadtree leaf node and coding the child coding units represented by leaf nodes of the binary tree with JVET, wherein further partitioning of child coding units split from quadtree leaf nodes via asymmetric binary partitioning is disallowed.

Apparatus comprises video data decoder circuitry configured to decode an input video data stream, the video data decoder being responsive to parameter data associated with the input video data stream, the parameter data indicating a profile selected from a plurality of profiles, each profile defining a decoding attribute comprising one or more of a bit depth and a chrominance subsampling format; detector circuitry configured to detect constraint data associated with the input video data stream, the constraint data defining a difference between a decoding attribute applicable to the input video data stream and the decoding attribute defined by the profile indicated by the parameter data, in which the constraint data is configured to indicate a zero difference of the decoding attribute by a zero value of the constraint data; and control circuitry configured to control the video data decoder to decode the input video data stream to generate a decoded video data stream having a decoding attribute defined by the encoding profile provided by the parameter data, as modified by the difference defined by the constraint data.

Disclosed herein are a QTBT split structure allowing blocks of various shapes capable of more efficiently reflecting various local characteristics of video and a method of efficiently signaling the split structure.

A method of converting 10-bit pixel data (e.g. 10:10:10:2 data) into 8-bit pixel data involves converting the 10-bit values to 8-bits using a technique that is selected dependent upon the values of the MSBs of the 10-bit values and setting the value of an HDR flag dependent upon the values of the MSBs. The HDR flag is appended to the 3-bit channel.

A method of partitioning a coding unit (CU) into one or more transform units (TUs) for encoding a video sequence using at least one processor includes determining a height of the CU; determining a width of the CU; determining a TU size of each of the one or more TUs based on the height of the CU and the width of the CU; determining one or more TU positions of the one or more TUs based on the height of the CU and the width of the CU; and partitioning the CU into the one or more TUs based on the determined size of the one or more TUs and the one or more positions of the one or more TUs.

An image decoding method performed by a decoding apparatus according to the present disclosure includes receiving a bitstream including residual information; deriving quantized transform coefficients for a current block based on the residual information included in the bitstream; deriving residual samples for the current block based on the quantized transform coefficients; and generating a reconstructed picture based on the residual samples for the current block.

A method of decoding JVET video, comprising receiving a bitstream indicating how a coding tree unit was partitioned into coding units according to a partitioning structure that allows nodes to be split according to a partitioning technique. An intra direction mode for a coding unit may be selected, as well as one or more of the plurality of reference lines to generate at least one predictor for the intra direction mode. A predictor may be generated from reference samples within each selected reference line by combining predicted pixel values based on a projected position on a main reference line in combination with predicted pixel values based on a projected position on a side reference line. The predicted pixel values are weighted according to a weight parameter, wherein the weight parameter is determined based on a shift conversion factor.