Abstract: Video encoding and decoding is implemented with auto encoders using luminance information to derive motion information for chrominance prediction. In one embodiment conditional convolutions are used to encode motion flow information. A current condition, for example, GOP structure, is used as input to a succession of fully connected layers to implement the conditional convolution. In a related embodiment, more than one reference frame is used to encode motion flow information.

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 comprises 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.

Abstract: The method for intra frame prediction allows for the recovery of some intra directional modes that are otherwise rendered useless due to the classical padding process. Directional modes are recovered by filling pixel locations in the prediction unit with samples from the portion of the unit that is determined to have samples available for use using a counterpart directional mode to the one that is useless. When it is determined that reference samples are missing for a particular prediction unit or portion thereof given a particular directional mode, a determination is made about whether reference samples along another portion of the prediction unit are available. The other portion is the side of the prediction unit at an opposite end of the particular directional mode.

Abstract: A method and apparatus for performing intra prediction for encoding or decoding adds multiple prediction modes to those of prior intra prediction schemes. A horizontal mode, a vertical mode, and a diagonal mode are added. Reference pixels for each of the added modes can come from multiple pixel positions away from a block to be encoded or decoded. Reference pixels to the left and above a block are reconstructed from those already coded. Reference pixels from right of, and below, a block are estimated or extrapolated and can be based on other pixels around the block. An index can be sent in a bitstream indicating which prediction was used.

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: Video encoding and decoding is implemented with auto encoders using luminance information to derive motion information for chrominance prediction. In one embodiment YUV 4:2:0 video is encoded and decoded in which luminance information is downsampled to generate predictions from chrominance components of a reference frame. In a related embodiment, more than one reference frame is used for predictions. In another embodiment, convolutions and transpose convolutions implement derivation of motion information.

Abstract: 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.

Abstract: 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 weights can be variable, chosen from among a number of number of sets of weights. 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. An index can be sent indicating which set of weights is to be used.

Abstract: Methods (1500, 1600) and apparatuses (700, 900, 1700) for video coding and decoding are provided. The method of video encoding (1500) includes determining (1510) 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 (1520) a prediction of the block based on the set of parameters, the prediction being associated with the first motion compensated reference block and encoding (1530) 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: In one embodiment of the disclosure, it is proposed a method for encoding a matrix of image views obtained from data acquired by a plenoptic camera. The method is remarkable in that it comprises: obtaining at least one reference image view from a combination of at least two image views from said matrix of image views; encoding image views that are different from said at least one reference image view, based on said at least one reference image view.

Abstract: A method includes decoding a first portion of video data consisting of an information set consisting of information representative of a plurality of candidate sets of sample adaptive offset filter parameters. A set of sample adaptive offset parameters comprises information representative of an offset to be added to a sample value of a current block. A first syntax element representing an index that identifies a first candidate set of the plurality of candidate sets of sample adaptive offset filter parameters is decoded from the video data for the current block. The current block is decoded from a second portion of the video data different from the first portion. The decoded current block is filtered with the first candidate set identified by the index. The first portion is signaled with syntax elements at a level of a block of a group of blocks comprising the current block decoded first in decoding order.

Abstract: A method and apparatus for performing intra prediction for encoding or decoding adds multiple prediction modes to those of prior intra prediction schemes. A horizontal mode, a vertical mode, and a diagonal mode are added. Reference pixels for each of the added modes can come from multiple pixel positions away from a block to be encoded or decoded. Reference pixels to the left and above a block are reconstructed from those already coded. Reference pixels from right of, and below, a block are estimated or extrapolated and can be based on other pixels around the block. An index can be sent in a bitstream indicating which prediction was used.

Abstract: The method for intra frame prediction allows for the recovery of some intra directional modes that are otherwise rendered useless due to the classical padding process. Directional modes are recovered by filling pixel locations in the prediction unit with samples from the portion of the unit that is determined to have samples available for use using a counterpart directional mode to the one that is useless. When it is determined that reference samples are missing for a particular prediction unit or portion thereof given a particular directional mode, a determination is made about whether reference samples along another portion of the prediction unit are available. The other portion is the side of the prediction unit at an opposite end of the particular directional mode.

Abstract: 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.

Abstract: Processing of a compressed representation of a video signal is optimized for multiple tasks, such as object detection, viewing of displayed video, or other machine tasks. In one embodiment, multiple analysis stages and a single synthesis is performed as part of a coding/decoding operation with training of an encoder side analysis and, optionally, a corresponding machine task. In another embodiment, multiple synthesis operations are performed on the decoding side, so that respective analysis, synthesis, and task stages are optimized. Other embodiments comprise feeding decoded feature maps to tasks, predictive coding, and using hyperprior-based models.

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 processing module, or connector, adapts an output of a codec, or a decoded output, to a form suitable for an alternate task. In one embodiment, the output of a codec is used for a machine task and the connector adapts this output to a form suitable for a video display. In another embodiment, metadata accompanies the codec output, which can instruct the connector how to adapt the codec output for an alternate task. In other embodiments, the processing module performs averaging over a N×M window, or convolution.

Abstract: A decoding method for decoding blocks of a picture part is disclosed that comprises: —decoding a plurality of candidate sets of filter parameters from a bitstream; —decoding for a current block of said picture an index identifying one of the accessing a bitstream candidate sets of filter parameters from said bitstream; —decoding said current block from said bitstream; and —filtering said decoded current block with the candidate set of filter parameters of filter parameters from a bitstream identified by said decoded index decoding for a current block an index.

Abstract: The present disclosure relates to methods, apparatus or systems for encoding and decoding sequence of images by applying a global rotation motion compensation to an input image. According to different embodiments, the input image is a reference image in a compression loop or the image to be encoded. The images to encode are omnidirectional images. As a result, applying a global rotation motion compensation to them corresponds to generate new images as if they have been captured according to a different front direction. When this new front direction is the one of a reference image, the compensation of apparent motion is facilitated.