Abstract: An apparatus for decoding a sequence of pictures from a data stream is configured for decoding a picture of the sequence by: deriving a residual transform signal of the picture from the data stream; combining the residual transform signal with a buffered transform signal of a previous picture of the sequence so as to obtain a transform signal of the picture, the transform signal representing the picture in spectral components; and subjecting the transform signal to a spectral-to-spatial transformation, wherein the buffered transform signal comprises a selection out of spectral components representing the previous picture.

Abstract: A Video conference apparatus is configured to reproduce videos of a plurality of video conference participants on a plurality of video reproduction areas or video reproduction spaces that are arranged in a spatial virtual reality environment. The video conference apparatus is configured to render the spatial virtual reality environment with the video reproduction areas or video reproduction spaces to a total image for a single video conference participant. A video conference method and a computer program are also disclosed.

Abstract: An apparatus for decoding a sequence of pictures from a data stream is configured for decoding a picture of the sequence by deriving a residual transform signal of the picture from the data stream; combining a residual transform signal with a buffered transform signal approximation of a previous picture of the sequence so as to obtain a transform signal representing the picture, the transform signal having a plurality of transform coefficients; and subjecting the transform signal to a spectral-to-spatial transformation. The apparatus is configured for deriving the buffered transform signal approximation from a further transform signal representing the previous picture so that the buffered transform signal approximation has approximations of further transform coefficients of the further transform signal.

Abstract: An apparatus for decoding a sequence of pictures from a data stream is configured for decoding a picture of the sequence by deriving a residual transform signal of the picture from the data stream; combining a residual transform signal with a buffered transform signal approximation of a previous picture of the sequence so as to obtain a transform signal representing the picture, the transform signal having a plurality of transform coefficients; and subjecting the transform signal to a spectral-to-spatial transformation. The apparatus is configured for deriving the buffered transform signal approximation from a further transform signal representing the previous picture so that the buffered transform signal approximation has approximations of further transform coefficients of the further transform signal.

Abstract: An apparatus for decoding a sequence of pictures from a data stream is configured for decoding a picture of the sequence by deriving a residual transform signal of the picture from the data stream; combining a residual transform signal with a buffered transform signal approximation of a previous picture of the sequence so as to obtain a transform signal representing the picture, the transform signal comprising a plurality of transform coefficients; and subjecting the transform signal to a spectral-to-spatial transformation. The apparatus is configured for deriving the buffered transform signal approximation from a further transform signal representing the previous picture so that the buffered transform signal approximation comprises approximations of further transform coefficients of the further transform signal.

Abstract: An apparatus for decoding a sequence of pictures from a data stream is configured for decoding a picture of the sequence by deriving a residual transform signal of the picture from the data stream; combining a residual transform signal with a buffered transform signal approximation of a previous picture of the sequence so as to obtain a transform signal representing the picture, the transform signal comprising a plurality of transform coefficients; and subjecting the transform signal to a spectral-to-spatial transformation. The apparatus is configured for deriving the buffered transform signal approximation from a further transform signal representing the previous picture so that the buffered transform signal approximation comprises approximations of further transform coefficients of the further transform signal.

Abstract: An apparatus for decoding a sequence of pictures from a data stream is configured for decoding a picture of the sequence by: deriving a residual transform signal of the picture from the data stream; combining the residual transform signal with a buffered transform signal of a previous picture of the sequence so as to obtain a transform signal of the picture, the transform signal representing the picture in spectral components; and subjecting the transform signal to a spectral-to-spatial transformation, wherein the buffered transform signal comprises a selection out of spectral components representing the previous picture.

Abstract: There is disclosed an encoder, a decoder, related methods, and non-transitory storage units storing instructions which, when executed by a computer, cause the computer to perform the methods. At an encoder (300), after a spatial transformation stage (304), there is obtained a spatially transformed version (306) of input image information (302) having multiple bands and, for each band, multiple transform band coefficients. After the generation of precincts (311), each comprising transform coefficients covering a predetermined spatial area of the input image information (302), there is provided a component transformation stage (320, 325), to apply one component transformation (CTr) selected (327) out of a plurality of predetermined component transformations, to each band (102?) of each precinct (311). Hence, there is obtained a spatially transformed and color transformed version (323) of the input image information (302), which is subsequently quantized and entropy encoded.

Abstract: A coding efficiency improvement is achieved by performing bit-plane coding in a manner so that coefficient groups for which the set of coded bit-planes is predictively signaled in the datastream, are grouped in two group sets and if a signal is spent in the datastream which signals, for a group set, whether the set of coded bit-planes of all coefficient groups of the respective group set are empty, i.e. all coefficients within the respective group sets are insignificant. In accordance with another aspect, a coding efficiency improvement is achieved by providing bit-plane coding with group-set-wise insignificant signalization according to the first aspect as a coding option alternative relative to the signalization for group sets for which it is signaled that there is no coded prediction residual for the coded bit-planes for the claim groups within the respective group set.

Abstract: A coding efficiency improvement is achieved by performing bit-plane coding in a manner so that coefficient groups for which the set of coded bit-planes is predictively signaled in the datastream, are grouped in two group sets and if a signal is spent in the datastream which signals, for a group set, whether the set of coded bit-planes of all coefficient groups of the respective group set are empty, i.e. all coefficients within the respective group sets are insignificant. In accordance with another aspect, a coding efficiency improvement is achieved by providing bit-plane coding with group-set-wise insignificant signalization according to the first aspect as a coding option alternative relative to the signalization for group sets for which it is signaled that there is no coded prediction residual for the coded bit-planes for the claim groups within the respective group set.

Abstract: A Video conference apparatus (100) is configured to reproduce videos (110a,110b) of a plurality of video conference participants on a plurality of video reproduction areas (120a,120b; 220a-220c; 420a-420d; 470a-470h) or video reproduction spaces that are arranged in a spatial virtual reality environment (120; 200; 300; 400; 450). The video conference apparatus is configured to render the spatial virtual reality environment (120; 200;300;400;450) with the video reproduction areas (120a,120b; 220a-220c; 420a-420d; 470a-470h) or video reproduction spaces to a total image (112) for a single video conference participant. A video conference method and a computer program are also disclosed.

Abstract: Concepts are presented herein how to efficiently create a suitable palette for low complexity image and video coding. A combination of the palette coding with transform coding is feasible.

Abstract: Transform block coding is performed very efficiently in terms of computational complexity and compression ratio, by coding the magnitude bits of the transform coefficients distributed in a matrix, in which the magnitude bits of the spectral coefficients are arranged column-wise with the spectral coefficients of the transform block ordered along a row direction of the matrix. That is, magnitude bits within a certain column of the matrix belong to a certain spectral coefficient, while magnitude bits within a certain row of the matrix belong to a certain bit plane. In this configuration, the distribution of non-zero magnitude bits may be condensed towards one corner of the matrix, corresponding to, for instance, the least significant bit plane and corresponding to, by using a scan order among the transform coefficients which sorts the transform coefficients generally in a manner from lowest to highest frequency, the lowest frequency. Various low complexity variants are presented.

Abstract: A coding efficiency improvement is achieved by performing bit-plane coding in a manner so that coefficient groups for which the set of coded bit-planes is predictively signaled in the datastream, are grouped in two group sets and if a signal is spent in the datastream which signals, for a group set, whether the set of coded bit-planes of all coefficient groups of the respective group set are empty, i.e. all coefficients within the respective group sets are insignificant. In accordance with another aspect, a coding efficiency improvement is achieved by providing bit-plane coding with group-set-wise insignificant signalization according to the first aspect as a coding option alternative relative to the signalization for group sets for which it is signaled that there is no coded prediction residual for the coded bit-planes for the claim groups within the respective group set.

Abstract: A coding efficiency improvement is achieved by performing bit-plane coding in a manner so that coefficient groups for which the set of coded bit-planes is predictively signaled in the datastream, are grouped in two group sets and if a signal is spent in the datastream which signals, for a group set, whether the set of coded bit-planes of all coefficient groups of the respective group set are empty, i.e. all coefficients within the respective group sets are insignificant. In accordance with another aspect, a coding efficiency improvement is achieved by providing bit-plane coding with group-set-wise insignificant signalization according to the first aspect as a coding option alternative relative to the signalization for group sets for which it is signaled that there is no coded prediction residual for the coded bit-planes for the claim groups within the respective group set.

Abstract: A coding efficiency improvement is achieved by performing bit-plane coding in a manner so that coefficient groups for which the set of coded bit-planes is predictively signaled in the datastream, are grouped in two group sets and if a signal is spent in the datastream which signals, for a group set, whether the set of coded bit-planes of all coefficient groups of the respective group set are empty, i.e. all coefficients within the respective group sets are insignificant. In accordance with another aspect, a coding efficiency improvement is achieved by providing bit-plane coding with group-set-wise insignificant signalization according to the first aspect as a coding option alternative relative to the signalization for group sets for which it is signaled that there is no coded prediction residual for the coded bit-planes for the claim groups within the respective group set.

Abstract: The invention relates to a raw image encoder for encoding a raw image of a predetermined color pattern according to which the raw image is partitioned into pixel cell blocks, each pixel cell block comprising four pixels, each pixel being associated with one of three base colors so that each pixel cell block comprises, for each of the three base colors, at least one pixel, the raw image encoder configured to subject the raw image to a color transformation to obtain a color image, by mapping, for each pixel cell block, the four pixels of the pixel cell block onto a color component quadruple forming a sample of the color image, the color component quadruple comprising three color component values of a target color space, and one pseudo color component value, and subject the color image to a multi-component picture encoding to obtain a compressed data stream.

Abstract: The invention relates to a raw image encoder for encoding a raw image of a predetermined color pattern according to which the raw image is partitioned into pixel cell blocks, each pixel cell block comprising four pixels, each pixel being associated with one of three base colors so that each pixel cell block comprises, for each of the three base colors, at least one pixel, the raw image encoder configured to subject the raw image to a color transformation to obtain a color image, by mapping, for each pixel cell block, the four pixels of the pixel cell block onto a color component quadruple forming a sample of the color image, the color component quadruple comprising three color component values of a target color space, and one pseudo color component value, and subject the color image to a multi-component picture encoding to obtain a compressed data stream.

Abstract: Concepts are presented herein how to efficiently create a suitable palette for low complexity image and video coding. A combination of the palette coding with transform coding is feasible.

Abstract: Transform block coding is performed very efficiently in terms of computational complexity and compression ratio, by coding the magnitude bits of the transform coefficients distributed in a matrix, in which the magnitude bits of the spectral coefficients are arranged column-wise with the spectral coefficients of the transform block ordered along a row direction of the matrix. That is, magnitude bits within a certain column of the matrix belong to a certain spectral coefficient, while magnitude bits within a certain row of the matrix belong to a certain bit plane. In this configuration, the distribution of non-zero magnitude bits may be condensed towards one corner of the matrix, corresponding to, for instance, the least significant bit plane and corresponding to, by using a scan order among the transform coefficients which sorts the transform coefficients generally in a manner from lowest to highest frequency, the lowest frequency. Various low complexity variants are presented.