Interdigital Vc Holdings, Inc.

Interdigital Madison Patent Holdings, Sas

Interdigital Ce Patent Holdings, Sas

Interdigital Patent Holdings, Inc.

Tangi Poirier

Fabrice Leleannec

Franck Galpin

Fabrice Urban

Ya Chen

Philippe Bordes

Antoine Robert

Gagan Bihari Rath

Karam Naser

Edouard Francois

Fabrice LeLeannec

Fabien Racape

Fabrice Le Leannec

Philippe De Lagrange

Sebastien Lasserre

Thierry Viellard

Yannick Olivier

Patrick Lopez

Gaëlle Martin-Cocher

Simon Danten

Fabrice Le Léannec

Methods and apparatus for implementing Discrete Trigonometric transforms are based on maximum transform size. In one embodiment, matrix-based intra prediction is enabled for coding unit sizes up to a specified size, regardless of the maximum transform size. In another embodiment, low-frequency non-separable transforms are used to improve coding gain. Syntax in a bitstream can be used to indicate a coding tool that is used.

Transform size interactions with coding tools

A video coding system uses a value of a chroma quantization parameter table to quantize or de-quantize chroma values of a block of the video, the chroma quantization parameter table being directly coded in a set of parameters at the picture level or at the sequence level of the coded video stream. A corresponding encoding method, encoding device, decoding method, decoding device, and non-transitory readable medium are proposed.

Chroma quantization parameter adjustment in video encoding and decoding

A decoding method for decoding a block of an image is disclosed that comprises: determining a split mode for said block in a set of split modes; splitting said block into at least two sub-blocks responsive to said split mode; decoding each of the at least two sub-blocks; wherein said set of split modes comprises at least one split mode for asymmetrically splitting said block into the at least two sub-blocks.

Encoding and decoding methods and corresponding devices

In an encoding apparatus or a decoding apparatus, an encoding method or decoding method combines various coding tools with intra sub partitioning mode in which a coding unit is split in multiple sub partitions. At least one embodiment particularly aims at the selection of primary transforms among a set of multiple transforms for video encoding or decoding of intra sub block partitions. At least one embodiment particularly aims at intra coding using Matrix-Based Intra Prediction mode combined with Intra Sub Partition mode. At least one embodiment particularly aims at intra coding using Multi-Reference-Line intra prediction mode combined with Intra Sub Partition mode.

Intra sub partitions for video encoding and decoding combined with multiple transform selection, matrix weighted intra prediction or multi-reference-line intra prediction

A method and apparatus to improve compression efficiency in a video compression scheme enables use of switchable interpolation filters. The interpolation filters are used on multiple partitions of video blocks, enabling better motion compensated prediction and improved video coding efficiency. In one embodiment, an interpolation filter index is derived for triangle partitions of a block from motion information candidate parameters, so that each unidirectional motion compensation can use a different value of interpolation filter index. In another embodiment, an interpolation filter index is a function of characteristics, such as shape or area, of video partitions.

Switchable interpolation filters

An encoding method is presented. Transform coefficients of a block are first obtained. They are then scanned according to a scan pattern for entropy coding. The scan pattern is determined responsive to a shape of the block.

Method and device for picture encoding and decoding

Different implementations are described, particularly implementations for determining a set of predictor candidates for affine merge coding mode from neighboring blocks for motion compensation of a picture block based on a motion model. The motion model, may be, e.g., an affine model in a merge mode or AMVP mode for a video content encoder or decoder. The motion model, may be, e.g., an affine model based on top-left/top-right control point motion vectors or an affine model based on top-left/bottom-left control point motion vectors. Such affine model may be signaled by a flag. In an embodiment, predictor candidates are sorted in the set based on a criterion such as, e.g., a validity check or a vectors coherence cost. In an embodiment, a predictor candidate is selected from the set based on a motion model for each of the multiple predictor candidates, and may be based on a criterion such as, e.g., a rate distortion cost. The corresponding motion field is determined based on, e.g., one or more corresponding control point motion vectors for the block being encoded or decoded. The corresponding motion field of an embodiment identifies motion vectors used for prediction of sub-blocks of the block being encoded or decoded.

Predictor candidates for motion compensation

Edges of the plurality of reference blocks are adjacent to a current block of a picture. A single transform is applied to samples of each reference block. A single transform is applied to samples of the current block. A decoding method includes decoding a plurality of reference blocks, obtaining a plurality of filtered reference blocks by filtering with a deblocking filter along the edges of the plurality of decoded reference blocks, and decoding the current block by intra prediction from the plurality of filtered reference blocks. An encoding method includes encoding and reconstructing a plurality of reference blocks, obtaining a plurality of filtered reference blocks by filtering with a deblocking filter along the edges of the plurality of reconstructed reference blocks, and encoding the current block by intra prediction from the plurality of filtered reference blocks.

Method and a device for decoding an intra predicted block of a picture and corresponding coding method and coding device

Various implementations for video encoding and decoding are presented involving determining, for a block being encoded or decoded in a picture, a coefficient group mode for coding at least one coefficient of a set of transform coefficients of the image block; encoding or decoding the set of transform coefficients of the image block responsive to the coefficient group mode. The coefficient group mode can be determined from at least one of image block size, number of non-zero transform coefficients inside the image block, position of a transform coefficient inside the image block, decoded syntax element, wherein the coefficient group mode can specify whether a coefficient group significance flag is coded/decoded, indicating that at least one coefficient is non-zero inside a coefficient group and/or specify at least one size of the coefficient group.

Method and apparatus for video encoding and decoding based on adaptive coefficient group

A decoding method is disclosed that comprises: determining whether a current block of a picture extends beyond a boundary of the picture; determining for each split mode of a plurality of split modes whether said current block is allowed to undergo splitting according to said split mode by checking whether at least one of the split line is co-located with one of the picture border or whether the size of the block part inside the picture along the picture boundary is a multiple of a minimum block size; decoding from a bitstream a current split mode of the current block responsive to the allowed split modes; and decoding the current block according to the current split mode.

Methods and apparatus for picture encoding and decoding

A decoding method is disclosed. First, context for a syntax element associated with a current transform coefficient of a block of a picture is determined. The context is determined based on the area of said block, on the position of the current transform coefficient within the block and on the number of non-zero neighboring transform coefficients in a local template. Second, the syntax element is decoded based at least on the determined context. Advantageously, the local template depends on the shape of said block.

At least a method and an apparatus are provided for efficiently encoding or decoding video. For example, a plurality of different motion prediction modes for a current block are obtained. The current block is encoded or decoded based on a combination of the plurality of different motion prediction modes with corresponding weights for a plurality of sub-blocks of the current block, wherein the combination with the corresponding weights comprising an inter prediction mode and an intra prediction mode.

Triangle and multi-hypothesis combination for video coding and decoding

Video encoding and decoding using non-rectangular partitioning. An example video decoding method includes: obtaining information identifying a non-rectangular first partitioning of a current block into a plurality of prediction units; determining a second partitioning of the current block into a plurality of transform units, wherein each transform unit is completely spatially contained within a respective one of the prediction units; and decoding the current block according to the non-rectangular first partitioning and the second partitioning. In some embodiments, the scan order of the transform units is determined such that all transform units contained in a same one of the prediction units are scanned before starting to scan transform units that are contained in a different one of the prediction units.

Method and device for intra-predictive encoding/decoding a coding unit comprising picture data, said intra-predictive encoding depending on a prediction tree and a transform tree

A method for video decoding ensuring a consistent interaction of some signaling tools with some encoding tools. The method is particularly advantageous when a container intended to provide parameters required for applying an encoding tool is missing while the encoding tool is activated for a given block. Examples include obtaining a first information indicating if a container of a first type providing at least one coding parameter is absent from the bitstream; checking a value of a first syntax element indicating if a coding tool using said at least one coding parameter is activated for a current block of samples of an image of the video sequence; and, adapting a decoding of the current block in case of absence of the container when the second syntax element indicates an activation of the coding tool.

Method and device for consistent interaction of signaling tools with encoding tools in video decoding

In some coding modes, such as the merge mode, a list of motion candidates is generated using spatial or temporal neighboring blocks or constructed ones, and one of the motion candidates is inherited by the current block. When constructing the list of motion candidates, motion information of a candidate to be added is checked to limit the redundancy in the constructed list. In one implementation, the switchable interpolation filter, the IFindex becomes part of the motion information to be used in comparison since it can modify the resulting prediction. Furthermore, the GBiIdx indicating the weights used in bi-prediction can also be part of the motion information to be compared and could also be taken into account in the redundancy check. In general, all or part of motion information that causes different prediction can be used in redundancy check.

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Cesson-Sevigne, France

Tangi Poirier