Abstract: Methods and apparatus for performing in-loop filtering in an encoder or a decoder provide regions which use a common set of filter parameters An index can be sent from an encoder to a decoder indicating which set of filter parameters is to be used for a particular region. The in-loop filter can be Sample Adaptive Offset, Adaptive Loop Filter, or any other such filter. An encoder classifies regions of a picture according to blocks using a common set of filter parameter. The classification can be in the form of a map. Filtering blocks use the common set of filter parameters for a region. A decoder parses a bitstream for a set of filter parameters and an index indicative of the filter parameter set for a region being decoded.

Abstract: Different implementations are described, particularly implementations for video encoding and decoding are presented including a method for deblocking an image. According to an implementation, in a method for deblocking an image, at least one boundary is determined between a first block of samples and a second block of samples; a boundary strength is determined according to at least one of a prediction mode of the first block and a prediction mode of the second block; and samples of the first and second blocks neighboring the at least one boundary are filtered according to the boundary strength. Advantageously, in case the prediction mode of the first block is a weighted prediction mode, the boundary strength further depends on the relative weight of samples used in predicting the first block of samples according to the weighted prediction mode of the first block and reciprocally for the second block.

Abstract: A restricted syntax range per layer in a multi-layer video coding scheme prevents inter-layer conflicts. In one embodiment, adaptive loop filtering sets defined in an adaptive parameter set are distinct in the multiple layers. In another embodiment, a layer identification is also used to uniquely identify the adaptation parameter set. In a related embodiment, a high-level syntax flag indicates whether a layer is independent of other layers.

Abstract: A method and an apparatus for encoding or decoding a video wherein for at least one first block to encode or decode, at least one reference sample is determined based on a coding mode used for reconstructing at least one second block. For instance, intrapadding or motion-compensation of a third block to which the at least one reference sample belong is performed using coding data of the at least one second block. A prediction is then obtained for the at least one first block using the at least one reference sample, and the at least one first block is encoded or decoded based on the prediction.

Abstract: A video coding system may use different types of templates when using template-based prediction modes such as intra template matching prediction mode. The ‘L-shape’ template conventionally used by template-based coding tools may be split into a horizontal ‘above’ (or ‘upper’) template and a vertical ‘left’ template. This allows the encoder to select the appropriate part of the template that better captures statistical properties of the current block and results into improving the coding performance. The use of the type of template is signaled in the encoded data so that the decoder can use the appropriate template for the reconstruction when using a template-based prediction mode such as intra template matching prediction mode.

Abstract: A method comprising obtaining (711) from video data an information allowing determining a picture order count difference between a picture order count of a current reference picture of a list of reference pictures associated to a current picture and a picture order count of the current picture; determining (712) the picture order count difference from the information; and, determining (713) a picture order count of the current reference picture from the picture order count difference; wherein, the determining of the picture order count difference from the information is based at least on a temporal identifier of the current picture.

Abstract: Encoding and decoding methods are disclosed wherein directional intra prediction is used. Each directional intra prediction mode of a given set is associated (S100) with a sum of gradient's values associated with pixels whose direction perpendicular to gradient's direction is the closest to a direction of said directional intra prediction mode and with information representative of a spatial position of each pixel contributing to the sum. At least two directional intra prediction modes are selected (S102) associated with the sums of largest amplitude and at least two predictions of said current picture block are obtained (S107) from them. Finally: the at least two predictions are blended (S108) based on information representative of a spatial position of at least one pixel contributing to the sum associated with at least one of said selected directional intra prediction modes. The current picture block is reconstructed (S110) from the blended prediction.

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 an example method, for a plurality of octants, residual information is obtained for one or more vertices of the respective octant, where the vertices correspond to respective points in a three-dimensional lookup table. The lookup table is decoded recursively as follows: at least a first one of the plurality of octants is decoded by reconstructing at least a first color sample value from the residual information for at least a first vertex of the first octant; and a plurality of second octants in the plurality of octants are decoded, where the second octants are obtained by splitting the first octant. A color transform is then applied based on the decoded lookup table.

Abstract: A coding block with ISP enabled may include multiple sub-partitions. For a first sub-partition in the coding block, an intra prediction mode may be derived based on the template samples associated with the first sub-partition. The first sub-partition may be decoded based on the intra prediction mode. For a second sub-partition in the coding block, an intra prediction mode may be derived based on the template samples associated with the second sub-partition, and the second sub-partition may be decoded based on that intra prediction mode. The sub-partitions in the coding block may independently derive an intra prediction mode using decoder side intra mode derivation and/or template-based intra mode derivation.

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: 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: Embodiments disclosed herein generally relate to methods and apparatuses for video coding. For example, methods and apparatuses using decoder-side motion vector refinement (DMVR) technique with bi-prediction weighting for video coding are provided. In an example, a method for video coding includes determining a mode with an illumination change, determining that at least one coding tool for a block is enabled, and performing a DMVR process based on the mode with the illumination change and the at least one coding tool for the block being enabled.

Abstract: A decoding method is disclosed. Information for identifying which pixels (e.g. decoded pixels) are unavailable inside a template of a current block of a picture is obtained. A template-based tool is further applied using the obtained information to determine information to be used for decoding the current block. Finally, the current block is decoded using the determined information.

Abstract: Prediction of a boundary used in geometric prediction modes is accomplished with embodiments that remove a requirement of reconstruction of samples of the current block, which increases pipeline latency. In one embodiment, the best boundary is predicted and added as a candidate to a list. In another embodiment, the candidates are ranked according to their boundary fitting score and an index is signaled to select the correct candidate at a corresponding decoder. In another embodiment, the fitting of the boundary is computed using a metric along the boundary sub-block. In another embodiment, the fitting of the boundary is computed using a metric outside the boundary area.

Abstract: Methods and apparatus for performing in-loop filtering in an encoder or a decoder provide regions which use a common set of filter parameters An index can be sent from an encoder to a decoder indicating which set of filter parameters is to be used for a particular region. The in-loop filter can be Sample Adaptive Offset, Adaptive Loop Filter, or any other such filter. An encoder classifies regions of a picture according to blocks using a common set of filter parameter. The classification can be in the form of a map. Filtering blocks use the common set of filter parameters for a region. A decoder parses a bitstream for a set of filter parameters and an index indicative of the filter parameter set for a region being decoded.

Abstract: A method comprising decoding a video is provided, wherein decoding the video includes determining at least one transform for a block of the video based on at least one part of reconstructed pixels surrounding the block, decoding the block by applying the at least one determined transform. An apparatus for decoding the video is also provided. Corresponding method and apparatus for encoding a video are also provided.

Abstract: Systems, methods, and instrumentalities are disclosed for performing local illumination compensation (LIC) with multiple linear models. In an example, a device, such as a video decoding device, or a video encoding device, may determine that sub-partition-based local illumination compensation (sub-LIC) is enabled for a current block. The device may divide the current block into a plurality of sub-partitions. The device may identify a plurality of templates associated with the plurality of sub-partitions. The device may derive a plurality of local illumination compensation (LIC) parameter sets associated with the plurality of sub-partitions based on the plurality of templates associated with the plurality of sub-partitions. The device may process (e.g., encode and/or decode) the current block based on the plurality of LIC parameter sets.

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: Decoder side intra mode derivation (DIMD) capability is enhanced by using reference pixels that extend several rows above and several columns left of a current video block, and also includes pixels above and left of the current video block, as well as columns above and right and rows below and left of the current video block. The reference pixels are formed from surrounding reconstructed/previously encoded samples surrounding the current video block. The derivation of an intra prediction mode is determined from gradients determined from each of the reference pixels in a defined surrounding area. In one embodiment, the gradients are determined using horizontal and vertical filters. In a sub-embodiment, the filters do not extend beyond the defined surrounding area. In another embodiment, reassignment of an index indicative of the target intra prediction mode is performed.