Abstract: A video decoder and a video encoder include a noise reduction operation including at least two denoising operations and adapting the second denoising operation in dependence of the difference before and after the first denoising operation, thus correcting the quality reduction occurred due to the application of the first denoising operation. Corresponding methods serve to encode and decode video signals.

Abstract: Wedgelet-based coding for coding blocks of varying size is rendered more efficient by the usage of a variable length coded syntax element having a prefix and a suffix, wherein the size of the suffix is dependent on the prefix and the size of the current coding block. By this measure, it is feasible to efficiently adapt the length of the variable-length coded syntax element which controls the bi-partitioning of the current coding block to the actual needs, namely the size, of the current coding block, and the variability of the bi-partitioning by varying the wedglet separation line, respectively. The greater the current coding block is, the longer the variable-length coded syntax element may be. This length dependency may even be sufficiently effective in terms of coding efficiency so that the variable length coded syntax element may be coded without context-adaptive entropy coding, but directly or using fixed-equal-probability binary entropy coding.

Abstract: A higher coding efficiency for coding a significance map indicating positions of significant transform coefficients within a transform coefficient block is achieved by the scan order by which the sequentially extracted syntax elements indicating, for associated positions within the transform coefficient block, as to whether at the respective position a significant or insignificant transform coefficient is situated, are sequentially associated to the positions of the transform coefficient block, among the positions of the transform coefficient block depends on the positions of the significant transform coefficients indicated by previously associated syntax elements. Alternatively, the first-type elements may be context-adaptively entropy decoded using contexts which are individually selected for each of the syntax elements dependent on a number of significant transform coefficients in a neighborhood of the respective syntax element, indicated as being significant by any of the preceding syntax elements.

Abstract: A video encoder encodes a video into a data stream, the video encoder being configured to vary a granularity at which a Quantization Parameter—QP—is applied depending on an association of frames of the video to temporally hierarchical layers at which the video is encoded into the data stream. The technology also concerns a respective decoder, a respective method for encoding and decoding, and a computer program for implementing the methods.

Abstract: A decoder is described, which receives an encoded data stream. The encoded data stream includes data representing a picture and a classification mode parameter. The classification mode parameter specifies a certain classification to be applied to samples in the picture, the certain classification selected from a plurality of classifications. The decoder decodes the encoded data stream to obtain a reconstructed picture and the classification mode parameter, classifies samples of the reconstructed picture into one of a plurality of classes using the certain classification specified by the classification mode parameter, and filters the samples of the reconstructed picture. A sample is filtered using a filter for the class into which the sample has been classified.

Abstract: Apparatus configured to derive a set-selective syntax element indicating whether the predetermined block is to be predicted using one of a first set of intra-prediction modes comprising a DC intra prediction mode and angular prediction modes. If the set-selective syntax element indicates that the predetermined block is to be predicted using one of the first set of intra-prediction modes, the apparatus is configured to use a list of most probable intra-prediction modes. If the set-selective syntax element indicates that the predetermined block is not to be predicted using one of the first set of intra-prediction modes, the apparatus is configured to use a matrix-based intra-prediction mode. The list of most probable intra-prediction modes is formed such that the list of most probable intra-prediction modes is free of the DC intra prediction mode in case of the neighbouring blocks being predicted by any of the angular intra prediction modes.

Abstract: Decoder for block-based decoding of an encoded picture signal using transform decoding, configured to select for a predetermined block a selected transform mode, entropy decode a block to be dequantized, which is associated with the predetermined block according to the selected transform mode, from a data stream and dequantize the block to be dequantized using a quantization accuracy, which depends on the selected transform mode, to obtain a dequantized block.

Abstract: In an encoder and a decoder for Region Based Intra Block Copy, the encoder may be configured for block-based encoding a picture into a data stream, and the decoder may be configured for block-based decoding a picture from a data stream. The encoder and decoder may further be configured to determine for a current block of the picture a difference between a first predetermined block and a second predetermined block inside a block search area. The encoder may encode the difference into the data stream and the decoder may derive the difference from the data stream. According to the innovative principle, the encoder and the decoder may be configured to partition the block search area into multiple block search regions.

Abstract: A video decoder for decoding a video from a data stream using block-based predictive decoding, the video decoder supporting a set of primitive prediction modes for predicting blocks of a picture of the video, is configured to predict a predetermined block by a composed prediction signal by deriving, using a collection of one or more primitive prediction modes out of the set of primitive prediction modes, a collection of one or more primitive predictions for the predetermined block, and composing the composed prediction signal for the predetermined block by combining the collection of one or more primitive predictions.

Abstract: A decoder for decoding a data stream into which media data is coded has a mode switch configured to activate a low-complexity mode or a high-efficiency mode depending on the data stream, an entropy decoding engine configured to retrieve each symbol of a sequence of symbols by entropy decoding using a selected one of a plurality of entropy decoding schemes, a desymbolizer configured to desymbolize the sequence of symbols to obtain a sequence of syntax elements, a reconstructor configured to reconstruct the media data based on the sequence of syntax elements, selection depending on the activated low-complexity mode or the high-efficiency mode.

Abstract: The present invention concerns an apparatus configured to partition a picture into leaf blocks using recursive multi-tree partitioning, block-based encode the picture into a data stream using the partitioning of the picture into the leaf blocks, wherein the apparatus is configured to, in partitioning the picture into the leaf blocks, for a predetermined block which extends beyond a boundary of the picture, reduce an available set of split modes depending on a position at which the boundary of the picture crosses the predetermined block in order to obtain a reduced set of one or more split modes, wherein the apparatus is configured to signal a selected split mode in the data stream.

Abstract: A higher coding efficiency for coding a significance map indicating positions of significant transform coefficients within a transform coefficient block is achieved by the scan order by which the sequentially extracted syntax elements indicating, for associated positions within the transform coefficient block, as to whether at the respective position a significant or insignificant transform coefficient is situated, are sequentially associated to the positions of the transform coefficient block, among the positions of the transform coefficient block depends on the positions of the significant transform coefficients indicated by previously associated syntax elements. Alternatively, the first-type elements may be context-adaptively entropy decoded using contexts which are individually selected for each of the syntax elements dependent on a number of significant transform coefficients in a neighborhood of the respective syntax element, indicated as being significant by any of the preceding syntax elements.

Abstract: Apparatus for predicting a predetermined block of a picture using a plurality of reference samples The apparatus is configured to form a sample value vector out of the plurality of reference samples, derive from the sample value vector a further vector onto which the sample value vector is mapped by a predetermined invertible linear transform, compute a matrix-vector product between the further vector and a predetermined prediction matrix so as to obtain a prediction vector, and predict samples of the predetermined block on the basis of the prediction vector.

Abstract: The handling of scalable data streams by network entities is rendered less complex by, in the data stream, accompanying packets which actually carry data by packets of a different packet type which have a scalability axes descriptor defining the number of scalability axes and a semantic meaning thereof. In another aspect, the handling of scalable data streams by network entities is rendered more efficient by conveying level and/or profile descriptors using packets other than the data carrying packets, with profile and/or level descriptors being divided up into a first set explicitly signaling the definition of the available coding option set and/or available syntax element value range for a respective operation point, and a second set of profile and/or level descriptors which signal the definition of the available coding option set and/or available syntax element value range for their respective operation points by reference another profile and/or level descriptor.

Abstract: A number of negatively affected (correctly received) packets due to packet loss is reduced by providing, and analyzing, error resilience in the packets of the sequence of packets and identifying, for each of runs of one or more lost packets of the sequence of packets, a first packet in the sequence of packets after the respective run of one or more lost packets, which carries a beginning of any of the tiles of the video data stream, and concurrently carries a slice, the slice header of which is contained in any of the packets of the sequence of packets not being lost. In particular, the side information overhead for transmitting the error resilience data is comparatively low compared to the reduction in negatively affected packets due to packet loss.

Abstract: A higher coding efficiency for coding a significance map indicating positions of significant transform coefficients within a transform coefficient block is achieved by the scan order by which the sequentially extracted syntax elements indicating, for associated positions within the transform coefficient block, as to whether at the respective position a significant or insignificant transform coefficient is situated, are sequentially associated to the positions of the transform coefficient block, among the positions of the transform coefficient block depends on the positions of the significant transform coefficients indicated by previously associated syntax elements. Alternatively, the first-type elements may be context-adaptively entropy decoded using contexts which are individually selected for each of the syntax elements dependent on a number of significant transform coefficients in a neighborhood of the respective syntax element, indicated as being significant by any of the preceding syntax elements.

Abstract: Video codec for supporting temporal inter-prediction, configured to perform padding of an area of a referenced portion of a reference picture which extends beyond a border of the reference picture, which referenced portion is referenced by an inter predicted block of a current picture by selecting one of a plurality of intra-prediction modes, and padding the area using the selected intra-prediction mode.

Abstract: An encoder for encoding weight parameters of a neural network is configured to obtain a plurality of weight parameters of the neural network, to encode the weight parameters of the neural network using a context-dependent arithmetic coding, to select a context for an encoding of a weight parameter, or for an encoding of a syntax element of a number representation of the weight parameter, in dependence on one or more previously encoded weight parameters and/or in dependence on one or more previously encoded syntax elements of a number representation of one or more weight parameters, and to encode the weight parameter, or a syntax element of the weight parameter, using the selected context. Corresponding decoder, quantizer, methods and computer programs are also described.

Abstract: Decoder for block-based decoding of a picture from a data stream, configured to decode an intra-coding mode for a predetermined block of the picture from the data stream, configured to decode a partition dimension flag for the predetermined block of the picture from the data stream and set a partition dimension depending on the partition dimension flag to be horizontal or vertical and the decoder is configured to partition, along the predetermined dimension, the predetermined block into transform partitions which are as wide as the predetermined block perpendicular to predetermined dimension, furthermore configured to decode, for each transform partition, a transform of a prediction residual from the data stream; intra-predicting the predetermined block depending on one or more already reconstructed samples neighboring the predetermined block in a manner depending on the intra-coding mode to obtain a predictor for the predetermined block; and reconstructing the predetermined block by correcting the predictor

Abstract: A video encoder according to embodiments is provided. The video encoder is configured for encoding a plurality of pictures of a video by generating an encoded video signal, wherein each of the plurality of pictures includes original picture data. The video encoder includes a data encoder configured for generating the encoded video signal including encoded picture data, wherein the data encoder is configured to encode the plurality of pictures of the video into the encoded picture data. Moreover, the video encoder includes an output interface configured for outputting the encoded picture data of each of the plurality of pictures. Furthermore, a video decoders, systems, methods for encoding and decoding, computer programs and encoded video signals according to embodiments are provided.