Abstract: A Local illumination compensation system for video encoding and decoding uses memory for storing illumination compensation parameters and does not require access to reconstructed pixels of neighboring blocks. A set of illumination compensation parameters is stored in a dedicated buffer, which is of limited size, and which is decoupled from the coding unit level storage of information. The buffer contains a set of illumination compensation parameters, which may be, for example, computed (or determined in some other manner) on the fly or determined beforehand (for example for example obtained from the video signal or from a device).

Abstract: In general, encoding or decoding a picture part can involve a first CABAC probability model associated with a first flag indicating use of an affine mode and a second CABAC probability model associated with a second flag indicating use of either the affine mode or a second mode different from the affine mode, where the first and second CABAC probability models are different and are determined independently.

Abstract: A method for decoding a picture block is disclosed. The decoding method comprises: —decoding (10) at least one stream S_diff into decoded data and into one information for identifying a re-constructed reference picture in a decoder picture buffer; —reconstructing (12) a special reference picture from at least the identified reconstructed reference picture and from the decoded data; —reconstructing (16) the picture block from at least the special reference picture, wherein the at least the special reference picture is not displayed.

Abstract: A method for encoding a video is provided, wherein encoding the video comprises classifying samples of a first picture, determining, for at least one part of the first picture, a first filter based on said classification, said first filter being used for a first encoding operation of the first picture or of a second picture, determining a second filter based on said classification, said second filter being used for a second encoding operation of the first picture or of the second picture. An apparatus for encoding a video, decoding method and apparatus are also provided.

Abstract: A method for encoding a LUT defined as a lattice of vertices is disclosed. At least one value is of each vertex of the lattice. The method comprises for a current vertex: predicting the at least one value of said current vertex from another value which is for example obtained from reconstructed values of neighboring vertices; and encoding in a bitstream at least one residue computed between the at least one value of the current vertex and its prediction in a bitstream.

Abstract: An image is split into a plurality of blocks of various sizes and a subdivision level counter is associated to each of the blocks. The value of this subdivision level counter for a block is representative of the size of the block and is used to determine the quantization parameter for the block. The value is propagated for each subdivision and incremented according the type of the subdivision. When the image is split, an analysis is done according to the subdivision level counter, a maximal value of subdivision and the type of split, in order to determine the start of a new quantization group and when it is the case, the current position of the partition is propagated to the further split partitions to be stored with these partition and serve in the prediction process when decoding.

Abstract: At least a method and an apparatus are presented for efficiently encoding or decoding video. For example, parameters for a local illumination compensation LIC of a current block being encoded/decoded in a picture are determined based on spatially neighboring reconstructed samples and corresponding spatially neighboring reconstructed samples of at least one spatial reference block, wherein the at least one spatial reference block is a spatially neighboring block of the current block in the picture. For example, a flag enables/disables the spatial LIC for the current block. For example, the spatial LIC is applied to any of an Inter/Intra/IBC prediction. For example, multiple spatial reference blocks are used in determining the spatial LIC parameters. For example, spatially neighboring reconstructed samples of multiple lines are used in determining the spatial/temporal LIC parameters.

Abstract: Systems, methods, and instrumentalities are disclosed for performing intra prediction of a luminance coding block and/or a chrominance coding block and related signaling when neural network-based intra prediction is enabled. For a current coding block, information representative of a neural network-based prediction mode and a block context may be obtained. A neural network-based predictor may be generated for the current coding block based on the block context and the neural network-based prediction mode. A non-neural network-based intra prediction mode that corresponds to the generated neural network-based predictor may be determined. A prediction mode for a neighboring block may be determined based on the non-neural network-based intra prediction mode.

Abstract: Described are methods and apparatuses wherein an illumination compensation parameter is determined for a current block of a picture. The illumination compensation parameter is determined from one or more illumination compensation parameters or from one or more reconstructed samples of at least one spatially neighbor block only in the case where said at least one spatially neighbor block belongs to the same local illumination compensation group as the current block, called current local illumination compensation group. Finally, the current block is reconstructed using the determined illumination compensation parameter.

Abstract: A method includes encoding a first message including first parameters for a first color transform that transforms a video signal into a first color-mapped video signal; encoding a second message including second parameters for a second color transform that transforms the video signal into a second color-mapped video signal; and encoding the video signal, the first message, and the second message in a video bitstream. A method includes decoding the video bitstream into the video signal, the first message including the first parameters, and the second message including the second parameters, and performing at least one of the following: displaying the video signal; transforming the video signal into the first color-mapped video signal by applying the first color transform and displaying the first color-mapped video signal; and transforming the video signal into the second color-mapped video signal by applying the second color transform and displaying the second color-mapped video signal.

Abstract: A method for reconstructing a block of a picture comprising: applying an inverse transform to a block of transform coefficients using a first matrix of integer coefficients representative of the inverse transform, wherein the first matrix of integer coefficients is the inverse of a second matrix of integer coefficients representative of a transform inverted to obtain the inverse transform, the second matrix of integer coefficients being derived from a third matrix of integer coefficients., the absolute values of the integer coefficients of the third matrix taking their values in a set of four different values, the derivation comprising a modification of one value of the set to ensure that a sum of two values of the set equals a third value of the set.

Abstract: Methods and apparatuses for video coding and decoding are provided. The method of video encoding includes determining a set of parameters for illumination compensation associated with a first motion compensated reference block of a block in a picture of a video based on a function of a set of samples of the first motion compensated reference block and a set of samples of a second motion compensated reference block of the block, processing a prediction of the block based on the set of parameters, the prediction being associated with the first motion compensated reference block and encoding the block based on the processed prediction. A bitstream formatted to include encoded data, a computer-readable storage medium and a computer program product are also described.

Abstract: A video coding system for an image of a video representative of a virtual environment comprises an encoder and a decoder that perform a reconstruction of a differential picture based on a decoded picture buffer, wherein the decoded picture buffer comprises a least a picture based on a reference differential picture and on a second picture generated by a three-dimensional renderer based on the information representative of the virtual environment. An encoding method and a decoding method are described and comprise adding the reconstructed differential picture is to the second picture.

Abstract: A method for reconstructing a picture block is disclosed, wherein the block is predicted using local illumination compensation. The parameters of local illumination compensation are determined according to a selection of reconstructed samples located to the left and above of the current block. In the case where some of them are unavailable, they may be replaced using different techniques.

Abstract: In general, encoding or decoding a picture part can involve a first CABAC probability model associated with a first flag indicating use of an affine mode and a second CABAC probability model associated with a second flag indicating use of either the affine mode or a second mode different from the affine mode, where the first and second CABAC probability models are different and are determined independently.

Abstract: In at least one embodiment, a method and apparatus for encoding/decoding a picture comprising predicting at least one block, wherein the predicting comprises performing motion compensation and local illumination compensation based on a reference block, the local illumination compensation including applying a linear model based on sums of absolute differences of neighboring reconstructed samples and corresponding reference samples of the reference block, wherein the neighboring reconstructed samples and corresponding reference samples of the reference block are co-located according to an L-shape substantially adjacent to the block to be predicted, the L-shape comprising a row of pixels located to the top side of the predicted block and a column of pixels located to the left side of the predicted block, the co-location being determined according a motion vector of the predicted block.

Abstract: Video processing can involve encoding and/or decoding a picture based on determining an activation of a processing mode involving a motion vector refinement process and a second process other than the motion vector refinement process; modifying the motion vector refinement process based on the activation and the second process; and encoding and/or decoding the picture based on the modified motion vector refinement process and the second process.

Abstract: Information for a switchable interpolation filter (SIF) is used independently for separate partitions in geometric merge mode, such as in Versatile Video Coding. The SIF information can be used in a prediction stage, stored in a geometric partition mode field, and to define the Adaptive Motion Vector Resolution precision of the geometric partition coded coding unit. In one embodiment, predictors from a candidate list are inherited from a SIF flag or from other candidates.

Abstract: Different implementations are described, particularly implementations for video encoding and decoding based on linear weighted intra prediction, also called matrix based intra prediction, are presented. Accordingly, the encoding or decoding comprises obtaining intra predicted samples of a block from a selected weight matrix and associated bias and from a set of neighboring reference samples; wherein any coefficient of the selected weight matrix is a power of two. According to relaxed version, not all but only a part of the coefficients of the selected weight matrix is a power of two. Advantageously, such arrangement allows to reduce the amount of memory for storing data and to reduce the complexity of the intra prediction samples computation.

Abstract: A method for encoding a video is provided, wherein encoding the video comprises classifying samples of a first picture, determining, for at least one part of the first picture, a first filter based on said classification, said first filter being used for a first encoding operation of the first picture or of a second picture, determining a second filter based on said classification, said second filter being used for a second encoding operation of the first picture or of the second picture. An apparatus for encoding a video, decoding method and apparatus are also provided.