Interdigital Vc Holdings, Inc.

Interdigital Madison Patent Holdings, Sas

Interdigital Ce Patent Holdings, Sas

Gagan Bihari Rath

Fabrice Urban

Fabien Racape

Tangi Poirier

Franck Galpin

Fabrice Leleannec

Fabrice LeLeannec

Karam Naser

Fabrice Le Leannec

Philippe Bordes

Antoine Robert

Edouard Francois

Ya Chen

Thierry Dumas

Gaëlle Martin-Cocher

Fabrice Le Léannec

Baptiste Esteban

Methods and apparatus for performing intra prediction in an encoder or a decoder for non-square blocks enable a combination of reference samples from a row above the non-square block and a row to the left of the non-square block to be used for the prediction. In one embodiment, a weighted combination of reference samples are used. In another embodiment, the angles of prediction are extended in the longer direction of the non-square block, such that less angles of prediction are used in the shorter direction.

Wide angle intra prediction and position dependent intra prediction combination

In one implementation, when coding a block in the intra prediction mode, the block can be split into two sub-partitions by a geometrically located straight line. Each geometric partition within the CU is intra predicted using its own intra mode with its available reference sample. One sub-partition copies and uses the intra prediction mode from the parent block, and another sub-partition uses another implicit or explicit signaled intra prediction mode. After predicting geometric partition, the sample values along the split boundary are adjusted using a blending process with adaptive weights. The geometric partition based intra prediction could be applied for one angular intra prediction mode, or only for one negative-directional intra prediction mode, or only for one specific intra prediction mode (e.g., mode 34). The transform selection or other intra coding tools (i.e., intra sub-partition) can be adapted for the geometric partition based intra prediction.

Intra prediction with geometric partition

Asymmetric binary trees are used in combination with coding tools such as transform unit tiling, affine motion compensation, decoder side motion vector refinement, and bidirectional optical flow. In another embodiment asymmetric binary trees is used in combination with subblock temporal motion vector prediction. Embodiments enable tiling of coding blocks into subblocks in accordance with coding tools such as used in Versatile Video Coding.

Combining ABT with VVC sub-block-based coding tools

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

Described are video coding systems comprising a post-processing stage using position dependent intra prediction combination where a predicted sample is modified based on a weighting between a value of a left or top reference sample and the obtained predicted value for the sample, wherein the left or top reference sample is determined based on the intra prediction angle. This provides better computing efficiency while keeping identical compression performance. Encoding method, decoding method, encoding apparatus and decoding apparatus based on this post-processing stage are proposed.

Method and device for picture encoding and decoding using position dependent intra prediction combination

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

Flexible methods to use a combination of coding modes while keeping good performance tradeoff are implemented with embodiments that determine coding mode information. In one embodiment, determination is made of activation of a first coding mode, and upon determination of whether a second coding mode is used, coding or decoding using the determined modes occurs. Other embodiments enable use of multiple reference lines, intra sub-block partitioning, matrix intra prediction, and low frequency non-separable transforms.

Method and apparatus using homogeneous syntax with coding tools

A video encoder or decoder processes portions of video using intra coding and with variable block shapes. Under the general aspects, intra prediction directions are adapted to the block shape or aspect ratio. The general aspects described adaptively replace several conventional angular intra prediction modes with wide-angle intra prediction modes for non-square blocks. The total number of angular directions for any block can remain the same as in prior video coding standards or can be reduced or expanded. To keep the same number of prediction directions, directions along a shorter rectangular edge of a target block are removed but replaced with addition directions along the longer edge of the rectangular target block. For directions with wide angles, reference sample smoothing is performed. Signaling can be provided to inform a corresponding decoder regarding the prediction modes and directions.

Block shape adaptive intra prediction directions for quadtree-binary tree

Decoding or encoding picture information can involve determining a value associated with a prediction of a pixel of a block of picture information, wherein, the prediction is based on an intra-prediction along a non-diagonal direction, determining, from among a plurality of decoded pixels neighboring the block on the top and the left, at least four reference samples for the block based on the non-diagonal direction, and wherein the determining of the value comprises an interpolation based on a quadratic model and the four reference samples; and decoding or encoding at least a portion of the picture information based on the value.

Intra prediction for video encoding and decoding

Video content frequently seen in gaming content and having a higher probability of being coded in transform skip mode is coded separately from remaining portions of a video coding block before being combined with regular coded portions. This enables more efficient coding of video by reducing the switching between regular coding modes and transform skip modes. The regular coded portion and the transform skip coded portion are combined in an encoder. At a corresponding decoder, inverse operations occur, such that the transform skipped residual portions are decoded and the regularly coded portions are decoded before the portions are combined for a resultant decoded video block.

Hybrid texture particle coding mode improvements

To encode a coding unit in the inter modes, there exist multiple inter modes that signal the motion information using a Motion Vector Predictor (MW) list. The MW lists for different coding modes include spatial predictors. In one embodiment, for all coding modes that use MVP lists, the top spatial predictor is first added to the motion vector predictor list before the left spatial predictor. In another embodiment, a subset of coding modes adds the top spatial predictor before the left spatial predictor, and another subset of coding modes adds the left spatial predictor before the top spatial predictor. For example, all merge modes add the top spatial predictor first, and all AMVP modes add the left spatial predictor first. In another example, all non-sub-block modes add the top spatial predictor first, and all sub-block modes add the left spatial predictor first.

Spatial predictor scan order

A method for video decoding is disclosed. A directional intra prediction mode is decoded for a block of a picture, the directional intra prediction mode having a direction. Based on the directional intra prediction mode, a first predictor and a second predictor for a sample in the current block are accessed, the first and second predictors being on a line at least approximating the direction. A sample value of the sample is predicted by interpolation using the first and second predictors, responsive to a difference between the second and first predictors, wherein the difference is scaled by at least a ratio that is based on a location of the sample in the block, and wherein a denominator of the ratio is a power of two regardless of the location of the sample. The sample of the block is reconstructed based on the predicted sample value.

Method and apparatus for low-complexity bi-directional intra prediction in video encoding and decoding

An improvement in coding efficiency is achieved through restrictions on successive divisions of asymmetric splitting in advanced video coding algorithms, which frequently rely on splitting of a block of video data prior to coding using several transform sizes. Successive divisions of asymmetric splitting are forbidden if an equivalent split can be attained using triple splitting. In an embodiment, a video block is split using successive splits, but the second type of split is dependent on the first type of split.

Reducing redundancy between tree types

The disclosure relates to a method for encoding image data, the method including intra-predicting, or predicting by combining inter-prediction and intra-prediction, a first block of the image data by using an intra-prediction mode using a first single transformation obtained by taking account of the first block size. The disclosure also relates to a method for encoding image data, a variable coding length being used for signaling a plurality of Prediction Modes by the encoding, the method comprising:—intra-predicting a first block of the image data by using an intra-prediction mode using a first transformation, the first transformation being obtained by taking account of the first block size, —encoding information signaling a use of the intra-prediction mode in a bitstream, the information being encoded as one of the plurality of Prediction Modes. The disclosure further relates to the corresponding decoding methods, devices and media.

Method and apparatus for coding/decoding picture data

A method of performing intra prediction for encoding or decoding uses multiple layers of reference samples. The layers are formed into reference arrays that are used by a function, such as a weighted combination, to form a final prediction. The prediction is used in encoding or decoding a block of video data. The weights can be determined in a number of ways, and for a given prediction mode, the same weights, or different weights can be used for all pixels in a target block. If the weights are varied, they can depend on the distance of the target pixel from reference arrays.

Growing community of inventors

Cesson-Sevigne, France

Gagan Bihari Rath