Abstract: In accordance with a first aspect, an improved compression efficiency is achieved by letting a block-wise picture codec support a set of intra-prediction modes according to which the intra-prediction signal for a current block of a picture is determined by applying a set of neighboring samples of the current block onto a neural network. A second aspect of the present application is that, additionally or alternatively to the spending of neural network-based intra-prediction modes, the mode selection may be rendered more effective by the usage of a neural network dedicated to determine a rank or a probability value for each of the set of intra-prediction modes by applying a set of neighboring samples thereonto with the rank or probability value being used for the selection of one intra-prediction mode out of the plurality of intra-prediction modes including or coinciding with the set of intra-prediction modes.

Abstract: In transform coefficient coding, predetermined sets of transforms may be used. Embodiments of the present invention provide an encoder and a decoder for encoding a picture into/from a data stream using block-based prediction and block-based residual coding, the encoder and decoder supporting a set of transforms for the block-based residual coding. The encoder and decoder are configured to determine a transform candidate list of transforms for a current residual block out of the set of transforms based on a height and a width of the current residual block, and to encode/decode a prediction residual within the residual block using one selected transform out of the selectable list of transforms and selectively signal/derive the selected transform in/from the data stream.

Abstract: A further coding efficiency increase may be achieved if for a current block of a picture, for which the bit stream signals one of supported partitioning patterns, a reversal of the partitioning by block merging is avoided. In particular, if the signaled one of the supported partitioning patterns specifies a subdivision of the block into two or more further blocks, a removal of certain coding parameter candidates for all further blocks, except a first further block of the further blocks in a coding order, is performed. Particularly, those coding parameter candidates are removed from the set of coding parameter candidates for the respective further block, the coding parameters of which are the same as coding parameters associated with any of the further blocks which, when being merged with the respective further block, would result in one of the supported partitioning pattern. This avoids redundancy between partitioning coding and merging coding.

Abstract: A better compromise between encoding complexity and achievable rate distortion ratio, and/or to achieve a better rate distortion ratio is achieved by using multitree sub-divisioning not only in order to subdivide a continuous area, namely the sample array, into leaf regions, but using the intermediate regions also to share coding parameters among the corresponding collocated leaf blocks. By this measure, coding procedures performed in tiles—leaf regions—locally, may be associated with coding parameters individually without having to, however, explicitly transmit the whole coding parameters for each leaf region separately. Rather, similarities may effectively exploited by using the multitree subdivision.

Abstract: Coding schemes for coding a spatially sampled information signal using sub-division and coding schemes for coding a sub-division or a multitree structure are described, wherein representative embodiments relate to picture and/or video coding applications.

Abstract: A favorable merging or grouping of simply connected regions into which the array of information samples is sub-divided, is coded with a reduced amount of data. To this end, a predetermined relative locational relationship is defined enabling an identifying, for a predetermined simply connected region, of simply connected regions within the plurality of simply connected regions which have the predetermined relative locational relationship to the predetermined simply connected region. Namely, if the number is zero, a merge indicator for the predetermined simply connected region may be absent within the data stream. In other embodiments, spatial sub-division is performed depending on a first subset of syntax elements, followed by combining spatially neighboring simply connected regions depending on a second subset of syntax elements, to obtain an intermediate sub-division.

Abstract: A video coding method and apparatus for codes a video in a data stream using block-based predictive coding by deriving a collection of one or more primitive predictions for a block using a set of primitive prediction modes adapted for predicting blocks of a picture of the video. Each primitive prediction in the collection of primitive predictions is derived using a respective primitive prediction mode from the set of primitive prediction modes. A composite prediction signal for the block is composed by combining primitive predictions from the collection of one or more primitive predictions, and the block is predicted using the composite prediction signal.

Abstract: In accordance with a first aspect, an improved compression efficiency is achieved by letting a block-wise picture codec support a set of intra-prediction modes according to which the intra-prediction signal for a current block of a picture is determined by applying a set of neighboring samples of the current block onto a neural network. A second aspect of the present application is that, additionally or alternatively to the spending of neural network-based intra-prediction modes, the mode selection may be rendered more effective by the usage of a neural network dedicated to determine a rank or a probability value for each of the set of intra-prediction modes by applying a set of neighboring samples thereonto with the rank or probability value being used for the selection of one intra-prediction mode out of the plurality of intra-prediction modes including or coinciding with the set of intra-prediction modes.

Abstract: In transform coefficient coding, predetermined sets of transforms may be used. Embodiments of the present invention provide an encoder and a decoder for encoding a picture into/from a data stream using block-based prediction and block-based residual coding, the encoder and decoder supporting a set of transforms for the block-based residual coding. The encoder and decoder are configured to determine a transform candidate list of transforms for a current residual block out of the set of transforms based on a height and a width of the current residual block, and to encode/decode a prediction residual within the residual block using one selected transform out of the selectable list of transforms and selectively signal/derive the selected transform in/from the data stream.

Abstract: Coding schemes for coding a spatially sampled information signal using sub-division and coding schemes for coding a sub-division or a multitree structure are described, wherein representative embodiments relate to picture and/or video coding applications.

Abstract: A better compromise between encoding complexity and achievable rate distortion ratio, and/or to achieve a better rate distortion ratio is achieved by using multitree sub-divisioning not only in order to subdivide a continuous area, namely the sample array, into leaf regions, but using the intermediate regions also to share coding parameters among the corresponding collocated leaf blocks. By this measure, coding procedures performed in tiles—leaf regions—locally, may be associated with coding parameters individually without having to, however, explicitly transmit the whole coding parameters for each leaf region separately. Rather, similarities may effectively exploited by using the multitree subdivision.

Abstract: Coding schemes for coding a spatially sampled information signal using sub-division and coding schemes for coding a sub-division or a multitree structure are described, wherein representative embodiments relate to a picture and/or video coding applications.

Abstract: A better compromise between encoding complexity and achievable rate distortion ratio, and/or to achieve a better rate distortion ratio is achieved by using multitree sub-divisioning not only in order to subdivide a continuous area, namely the sample array, into leaf regions, but using the intermediate regions also to share coding parameters among the corresponding collocated leaf blocks. By this measure, coding procedures performed in tiles—leaf regions—locally, may be associated with coding parameters individually without having to, however, explicitly transmit the whole coding parameters for each leaf region separately. Rather, similarities may effectively exploited by using the multitree subdivision.

Abstract: A better compromise between encoding complexity and achievable rate distortion ratio, and/or to achieve a better rate distortion ratio is achieved by using multitree sub-divisioning not only in order to subdivide a continuous area, namely the sample array, into leaf regions, but using the intermediate regions also to share coding parameters among the corresponding collocated leaf blocks. By this measure, coding procedures performed in tiles—leaf regions—locally, may be associated with coding parameters individually without having to, however, explicitly transmit the whole coding parameters for each leaf region separately. Rather, similarities may effectively exploited by using the multitree subdivision.

Abstract: A favorable merging or grouping of simply connected regions into which the array of information samples is sub-divided, is coded with a reduced amount of data. To this end, a predetermined relative locational relationship is defined enabling an identifying, for a predetermined simply connected region, of simply connected regions within the plurality of simply connected regions which have the predetermined relative locational relationship to the predetermined simply connected region. Namely, if the number is zero, a merge indicator for the predetermined simply connected region may be absent within the data stream. In other embodiments, spatial sub-division is performed depending on a first subset of syntax elements, followed by combining spatially neighboring simply connected regions depending on a second subset of syntax elements, to obtain an intermediate sub-division.

Abstract: Apparatus (54) for decoding a predetermined block (18) of a picture using intra-prediction, configured to read, from a data stream (12), a mode index (200) using a binarization code (202). The mode index (200) points to one out of a list (204) of matrix-based intra-prediction modes. The apparatus is configured to predict samples (108) of the predetermined block (18) by computing a matrix-vector product (206) between an input vector (102) derived from reference samples (17) in a neighbourhood of the predetermined block (18) and a prediction matrix (19) associated with the matrix-based intra-prediction mode (k) pointed to by the mode index (200) and associating components (210) of an output vector (208) obtained by the matrix-vector product (206) onto sample positions (104) of the predetermined block. The list (204) of matrix-based intra-prediction modes consists of an even number of matrix-based intra-prediction modes.

Abstract: A coding efficiency increase is achieved by using a common signalization within the bitstream with regard to activation of merging and activation of the skip mode. One possible state of one or more syntax elements within the bitstream may signalize for a current sample set of a picture that the sample set is to be merged and has no prediction residual encoded and inserted into the bitstream. A common flag may signalize whether the coding parameters associated with a current sample set are to be set according to a merge candidate or to be retrieved from the bitstream, and whether the current sample set of the picture is to be reconstructed based on a prediction signal depending on the coding parameters associated with the current sample set, without any residual data, or to be reconstructed by refining the prediction signal depending on the coding parameters associated with the current sample set by means of residual data within the bitstream.

Abstract: A further coding efficiency increase may be achieved if for a current block of a picture, for which the bit stream signals one of supported partitioning patterns, a reversal of the partitioning by block merging is avoided. In particular, if the signaled one of the supported partitioning patterns specifies a subdivision of the block into two or more further blocks, a removal of certain coding parameter candidates for all further blocks, except a first further block of the further blocks in a coding order, is performed. Particularly, those coding parameter candidates are removed from the set of coding parameter candidates for the respective further block, the coding parameters of which are the same as coding parameters associated with any of the further blocks which, when being merged with the respective further block, would result in one of the supported partitioning pattern. This avoids redundancy between partitioning coding and merging coding.

Abstract: A better compromise between encoding complexity and achievable rate distortion ratio, and/or to achieve a better rate distortion ratio is achieved by using multitree sub-divisioning not only in order to subdivide a continuous area, namely the sample array, into leaf regions, but using the intermediate regions also to share coding parameters among the corresponding collocated leaf blocks. By this measure, coding procedures performed in tiles—leaf regions—locally, may be associated with coding parameters individually without having to, however, explicitly transmit the whole coding parameters for each leaf region separately. Rather, similarities may effectively exploited by using the multitree subdivision.

Abstract: Coding schemes for coding a spatially sampled information signal using sub-division and coding schemes for coding a sub-division or a multitree structure are described, wherein representative embodiments relate to picture and/or video coding applications.