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: An apparatus for checking a video data stream on trustworthiness derives a number of substreams of a predetermine temporal segment out of a sequence of temporal segments, in units of which the video data stream is checkable on trustworthiness, and further derives dependency information, which indicates, for the substream, whether the substream is dependent or whether the substream depends on one or more reference substreams. The trustworthiness check is performed by forming a verification stream based on a hash value, which is obtained from a portion of the substream to be verified and based on a reference hash value. If the substream is independent, a hash value derived for a corresponding substream of the preceding temporal segment is used as the reference hash value.

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: Techniques for block wise encoding and decoding may be applied to encoders, decoders, and methods for encoding or decoding and include assigning, based on a first signalization in the data stream, the predetermined block to the first set or the second set, sorting the assigned set of intra-prediction modes according to intra-prediction modes used for neighboring blocks, neighboring the predetermined block, to obtain a list of intra prediction modes, deriving, for the predetermined block, from the data stream, an index into the list of intra prediction modes, predicting the predetermined block using an intra prediction mode onto which the index points. The decoder or encoder, if the assigned set is the first set of intra-prediction modes, in sorting the assigned set, uses a second mapping which maps each intra-prediction mode of the second set of prediction modes onto a representative one in the first set of intra-prediction modes.

Abstract: An apparatus for checking a video data stream on trustworthiness derives a number of substreams of a predetermine temporal segment out of a sequence of temporal segments, units of which the video data stream is checkable on trustworthiness, and further derives dependency information, which indicates, for the substream, whether the substream is dependent or whether the substream depends on one or more reference substreams. The trustworthiness check is performed by forming a verification stream based on a hash value, which is obtained from a portion of the substream to be verified and based on a reference hash value. If the substream is independent, a hash value derived for a corresponding substream of the preceding temporal segment is used as the reference hash value.

Abstract: Video decoder for decoding a video of a scene from a data stream using motion-compensated prediction, configured to derive, for a current block of a current picture, a predicted block inner by finding in a reference picture corresponding positions, corresponding to pixels in the current block, using video-geometry-related parameters describing how the scene is projected onto pictures of the video, and sampling the reference picture at the corresponding positions, and reconstruct the current block using the predicted block inner.

Abstract: An apparatus includes at least one processor for decoding a block of a picture using intra-prediction that is configured to: decode, from a data stream, a mode index, the mode index indicating a matrix-based intra-prediction mode out of a plurality of matrix-based intra-prediction modes based on a size of the block, derive an input vector based on downsampling reference samples neighboring the block, determine a matrix based on the size of the block and the mode index, compute a respective output for each component of a matrix-vector product between the the input vector and the determined matrix, the respective output computed by performing, a right shift by a number of bits which is independent of the matrix-based intra-prediction mode indicated by the mode index, and for each component of the matrix-vector product, use the respective output to predict a respective sample of the block.

Abstract: An apparatus for block-based predictive decoding of a picture comprises a combiner configured to combine a residual signal a predetermined block of the picture and a reference signal for the predetermined block so as to obtain a first spectrum, the residual signal correcting a prediction error of a prediction of the predetermined block of the picture; a reducer configured to perform thresholding on the first spectrum to obtain a second spectrum so that coefficients below a threshold value are set to a predefined value; an extractor configured to obtain from the second spectrum a modified version of the residual signal; and a reconstructor block configured to decode the predetermined block of the picture from the data stream on the basis of the modified version of the residual 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: 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 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: 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.

Abstract: An apparatus includes at least one processor for decoding a block of a picture using intra-prediction that is configured to: decode, from a data stream, a mode index, the mode index indicating a matrix-based intra-prediction mode out of a plurality of matrix-based intra-prediction modes based on a size of the block, derive an input vector based on downsampling reference samples neighboring the block, determine a matrix based on the size of the block and the mode index, compute a respective output for each component of a matrix-vector product between the input vector and the determined matrix, the respective output computed by performing, a right shift by a number of bits which is independent of the matrix-based intra-prediction mode indicated by the mode index, and for each component of the matrix-vector product, use the respective output to predict a respective sample of the block.

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 method for checking a video data stream having a video encoded thereinto on trustworthiness comprises: subjecting a predetermined portion of the video data stream, or data derived therefrom, to a hash function to obtain a hash value; deriving a digital signature from the video data stream; and checking whether the hash value fits to the digital signature to determine whether the video data stream is trustworthy.

Abstract: Video decoder and encoder using a neighborhood signal generated by using a contribution signal in a version not post-processed and/or substituting a contribution signal by a substitute signal generated independent from spatial signal-interdependencies. Picture-processing tool configured to polyphase-wisely split luma samples and subject a tensor of cascaded matrices of the polyphase-components to a neural network or a convolution. Video decoder and encoder applying a post-processing only to certain inter-predicted blocks.

Abstract: A method for checking a video data stream having a video encoded thereinto on trustworthiness comprises: subjecting a predetermined portion of the video data stream, or data derived therefrom, to a hash function to obtain a hash value; deriving a digital signature from the video data stream; and checking whether the hash value fits to the digital signature to determine whether the video data stream is trustworthy.