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: An encoding scheme is provided for arithmetically encoding a sequence of information values into an arithmetic coded bitstream by providing the bitstream with entry point information, allowing for resuming arithmetic decoding of the bitstream from a predetermined entry point onward. A respective decoding scheme is also provided. These encoding and decoding schemes provide more efficient encoding in view of the decoding speed.

Abstract: An encoding scheme is provided for arithmetically encoding a sequence of information values into an arithmetic coded bitstream by providing the bitstream with entry point information, allowing for resuming arithmetic decoding of the bitstream from a predetermined entry point onward. A respective decoding scheme is also provided. These encoding and decoding schemes provide more efficient encoding in view of the decoding speed.

Abstract: Aspects of a trustworthiness check of a video data stream are described. According to a first aspect, a unique identifier which identifies a media asset to which a portion of a video data stream to be checked on trustworthiness belongs, is included into the trustworthiness check. According to a second aspect, a certificate of a content provider for performing the trustworthiness check is retrieved from a track of editors stored at an external resource. A third aspect provides a method for identifying a portion of a video data stream to be checked on trustworthiness using a digital signature. According to a fourth aspect, a digital signature for checking a portion of a video data stream is retrieved from an external resource.

Abstract: A video encoder is disclosed that is configured to encode a slice of a current picture into a data stream by partitioning the slice into rows of Coding Tree Units (CTUs), select a CTU dependency offset for the slice out of a plurality of CTU dependency offsets, the CTU dependency offset indicating a minimum CTU offset between consecutive CTU rows to be obeyed by a decoder when decoding CTU rows in parallel, and signal the CTU dependency offset in the data stream. The CTU dependency offset is selected based on a slice type of the slice.

Abstract: Wedgelet separation lines of neighboring blocks are predicted from each other by aligning the wedgelet separation lines of such neighboring blocks to each other, thereby reducing the side information coding rate that may be used.

Abstract: An encoding scheme is provided for arithmetically encoding a sequence of information values into an arithmetic coded bitstream by providing the bitstream with entry point information, allowing for resuming arithmetic decoding of the bitstream from a predetermined entry point onward. A respective decoding scheme is also provided. These encoding and decoding schemes provide more efficient encoding in view of the decoding speed.

Abstract: A better rate distortion ratio is achieved by making interrelationships between coding parameters of different planes available for exploitation for the aim of redundancy reduction despite the additional overhead resulting from the need to signal the inter-plane prediction information to the decoder. In particular, the decision to use inter plane prediction or not may be performed for a plurality of planes individually. Additionally or alternatively, the decision may be done on a block basis considering one secondary plane.

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: 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: Reconstructing a second component signal relating to a second component of a multi-component picture from a spatially corresponding portion of a reconstructed first component signal and a correction signal derived from data stream for the second component promises increased coding efficiency over a broader range of multi-component picture content. By including the spatially corresponding portion of the reconstructed first component signal into the reconstruction of the second component signal, any remaining inter-component redundancies/correlations present such as still present despite a possibly a priori performed component space transformation, or present because of having been introduced by such a priori performed component space information, for example, may readily be removed by way of the inter-component redundancy/correlation reduction of the second component signal.

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 method for decoding a block of a picture includes decoding, from a data stream, an intra-coding mode for the block, deriving a predictor for a prediction partition of the block using at least one already reconstructed samples neighboring the prediction partition and the intra-coding mode, deriving a prediction residual for each of the at least two transform partitions included in the prediction partition, and combining the predictor of the prediction partition and the prediction residual for each of the at least two transform partitions included in the prediction partition to reconstruct the prediction partition. The block is partitioned into multiple transform partitions based on a partition dimension flag, and the prediction partition includes at least two transform partitions of the multiple transform partitions.

Abstract: A previously encoded or reconstructed version of a neighborhood of a predetermined block to be predicted is exploited so as to result into a more efficient predictive coding of the prediction block. In particular, a spectral decomposition of a region composed of this neighborhood and a first version of a predicted filling of the predetermined block results into a first spectrum which is subject to noise reduction and the thus resulting second spectrum may be subject to a spectral composition, thereby resulting in a modified version of this region including a second version of the predicted filling of the predetermined block. Owing to the exploitation of the already processed, i.e. encoded/reconstructed, neighborhood of the predetermined block, the second version of the predicted filling of the predetermined block tends to improve the coding efficiency.

Abstract: An encoding scheme is provided for arithmetically encoding a sequence of information values into an arithmetic coded bitstream by providing the bitstream with entry point information, allowing for resuming arithmetic decoding of the bitstream from a predetermined entry point onward. A respective decoding scheme is also provided. These encoding and decoding schemes provide more efficient encoding in view of the decoding speed.

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 video decoder includes one or more processors that are configured to: determine that a picture is in a 4:4:4 color sampling format, determine, based at least in part on an index signaled in a data stream, a matrix-based intra prediction (MIP) mode, decode a luma block of the picture using the MIP mode, determine, for a chroma block of the picture, whether a coding tree of the chroma block is a single tree, select an intra prediction mode for decoding the chroma block, and decode the chroma block using the selected intra prediction mode. The selected intra prediction mode is the MIP mode in response to the coding tree of the chroma block being the single tree, and the selected intra prediction mode is a planar intra prediction mode in response to the coding tree of the chroma block not being the single tree.

Abstract: Apparatuses and methods for checking a data stream on trustworthiness are described. According to an aspect, the data stream indicates, whether a segment is a first segment or whether a segment is a last segment of assigned sequence of segments. According to another aspect, an apparatus for decoding a data stream is configured for deriving, from the data stream, whether a verification chain within a temporal sequence of segments is interrupted at a segment.

Abstract: Apparatuses and methods for checking a data stream on trustworthiness are described. According to an aspect, one or more supplemental information messages are considered in the trustworthiness of a data stream. According to another aspect, the data stream indicates, whether a segment is a first segment or whether a segment is a last segment of assigned sequence of segments. According to further segments, repetitions of certain supplemental information messages within certain portions of a data stream are either not included in the trustworthiness check, or are forbidden in the data stream.

Abstract: Apparatuses and methods for checking a data stream on trustworthiness are described. According to an aspect, the data stream comprises an indication which indicates whether one or more supplemental information messages are to be included into a portion of the data stream, which portion is to be used for performing a trustworthiness check of the data stream.