Abstract: This method for hole filling of a point cloud having at least one hole comprises:—detecting (2) boundary points of the point cloud;—grouping (12) the detected boundary points in boundary regions based on their spatial adjacency;—covering (16) each boundary region with at least one plane; and—inserting (18) new points in the point cloud using the planes covering the boundary regions.

Abstract: A method and device for point cloud compression are provided. A bitstream is generated that comprises color information data representative of a texture image from which points of the point cloud are colorized when reconstructing the point cloud. The bitstream also comprises an interpolation texture coding mode indicating that texture interpolation has to be done on points of the reconstructed point cloud that are not colorized from the texture image.

Abstract: The present disclosure concerns a method for reconstructing a point cloud representing a 3D object from an inverse-projected point cloud obtained by inverse-projecting at least one depth image of an original point cloud, said at least one depth image being obtained by projecting points of the original point cloud onto at least one surface, said method comprising the steps of detecting at least one missing part in the inverse-projected point cloud, and completing said at least one missing part based on points in the neighborhood of said at least one missing part.

Abstract: Different implementations are described, particularly implementations for processing a medium dynamic range video signal are presented. In a method for processing such a video signal a medium dynamic range video signal and associated metadata are received, wherein the metadata include data representative of a peak luminance value of the medium dynamic range video signal. In addition, data representative of a peak luminance value of a presentation display are received. It is determined whether the peak luminance value of the medium dynamic range video signal is greater or lower than the peak luminance value of the presentation display. A processor is configured based on the determination, wherein the processor has a first mode to reconstruct a high dynamic range video signal based on a received standard dynamic range video signal and associated metadata, and a second mode to optimize a received high dynamic range video signal for the rendering device.

Abstract: Various implementations for video encoding and decoding are presented involving determining, for a block being encoded or decoded in a picture, a coefficient group mode for coding at least one coefficient of a set of transform coefficients of the image block; encoding or decoding the set of transform coefficients of the image block responsive to the coefficient group mode. The coefficient group mode can be determined from at least one of image block size, number of non-zero transform coefficients inside the image block, position of a transform coefficient inside the image block, decoded syntax element, wherein the coefficient group mode can specify whether a coefficient group significance flag is coded/decoded, indicating that at least one coefficient is non-zero inside a coefficient group and/or specify at least one size of the coefficient group.

Abstract: Coding of the last coded coefficient position is performed by basing the coding of they coordinate of the position of the last coded coefficient on knowledge of the size of the partial transform used to generate a block of coefficients from a block of video pixels. This enables a context adaptive coding of the last coded coefficient parameter to be performed much more efficiently.

Abstract: A block of video data is split using one or more of several possible partition operations by using the partitioning choices obtained through use of a texture-based image partitioning. In at least one embodiment, the block is split in one or more splitting operations using a convolutional neural network. In another embodiment, inputs to the convolutional neural network come from pixels along the block's causal borders. In another embodiment, boundary information, such as the location of partitions in spatially neighboring blocks, is used by the texture analysis. Methods, apparatus, and signal embodiments are provided for encoding.

Abstract: Significance flags in advanced video compression systems are coded using contexts adaptive to the last N significance flags coded taken in a scanning order. One embodiment uses the last N significance flags in scanning order as a predictor to determine which of a plurality of sets of significance flag contexts to use for coding subsequent significance flags. A second embodiment uses the last N significance flags in scanning order as a predictor in order to modulate the probability value associated with significance flag contexts that are used to code significance flags for future coding.

Abstract: Different implementations are described; particularly implementations for video encoding and decoding using merge lists comprising history-based motion vector predictor candidates and averaged motion vector predictor candidates. The method comprises: determining for a current block of the picture one or more history-based motion vector predictor candidates using motion information of blocks preceding the current block; determining for the current block one or more averaged motion vector predictor candidates by averaging a pair of motion vector predictor candidates in a list of motion vector predictor candidates, wherein the motion vector predictor candidates in the list are formed using motion information of blocks spatially and/or temporally surrounding the current block; and inserting one or more of the averaged motion vector predictor candidates before one or more of the history-based motion vector predictor candidates in the list of motion vector predictor candidates.

Abstract: According to the invention, the saturation thresholds (thr; thg; thb) used for this detection depend on color coordinates (rw, gw, bw) representing an illuminant (ILL) of the image.

Abstract: Different implementations are described, particularly implementations for video encoding and decoding based on wherein the partitioning tree structure is partially shared between luma and chroma blocks are presented. According to an implementation, a single partitioning tree structure is shared between luma and chroma blocks from a root node of the partitioning tree down to a switching node and a dual partitioning tree structure is determined for luma and chroma blocks from the switching node down to a leaf node of the partitioning tree. Thus, this implementation optimizes the coding efficiency by allowing separated trees for smaller blocks, while limiting the complexity of decoding pipeline.

Abstract: Methods and apparatus are provided for collaborative partition coding for region based filters. An apparatus includes a video encoder (100) for encoding image data for a plurality of regions in a picture. The video encoder (100) includes multiple filters for filtering the image data based on region partition information for the plurality of regions. The region partition information for the plurality of regions is shared between the multiple filters.

Abstract: A method and a device provide for transmitting information representing a viewpoint in a 3D scene represented with a set of volumetric video contents; receiving a first volumetric video content of the set, the first volumetric video content being according to a range of points of view comprising the viewpoint, the first volumetric video content being represented with a set of first patches, each of which corresponds to a 2D parametrization of a first group of points in a 3D part of the 3D scene associated with the first volumetric video content, and at least one first patch refers to an area of a second patch corresponding to a 2D parametrization of a second group of points in another 3D part of the 3D scene associated with a second volumetric video content of the set of volumetric video contents.

Abstract: Methods and apparatuses for video coding and decoding are provided. The method of video encoding includes accessing (1410) a bin of a syntax element associated with a block in a picture of a video, determining (1420) a context for the bin of the syntax element from a set of contexts associated with a block type of the block, the set of contexts including at least a first context and a second context, the second context being associated with a larger number of block types than the first context and entropy encoding (1430) the bin of the syntax element based on the determined context. A bitstream formatted to include encoded data, a computer-readable storage medium and a computer-readable program product are also described.

Abstract: A method for encoding a picture block is disclosed. A predictor is determined as a weighted sum of sample values of a first motion compensated reference block in a first reference image and of a second motion compensated reference block in a second reference image. Then, a residual block determined from the picture block and the predictor is encoded in a bitstream. Advantageously, the weights of the weighted sum are determined by minimizing an error between reconstructed samples neighboring the picture block and samples neighboring the first and second reference blocks.

Abstract: Encoders and decoders of digital video signals use combined intra prediction modes for some images. In at least one embodiment, combined intra prediction modes can result from the intra prediction modes of neighboring blocks. The combined intra prediction mode can be added to a most probable modes list. Various embodiments describe techniques for combining the intra prediction modes, comprising a combination of reference samples and a combination of directions to form a prediction. Another embodiment adds a combination mode to the most probable modes list if the two modes that are combined to form it are directional modes with angle difference less than 90 degrees. Another embodiment uses a linear combination of intra prediction modes and another embodiment performs a linear combination which depends on the distance of a prediction from the left and above blocs.

Abstract: The present principles relate to a method and device method for encoding depth values of orthogonally projected points of a point cloud onto a projection plane. The present principles also relate to a method and device for decoding a point cloud, a computer readable program and a video signal.

Abstract: Different implementations are described, particularly implementations for video encoding and decoding using entropy coding of quantized transform coefficients. The method comprises: determining context model indices for one or more syntax elements of quantized transform coefficients of a transform block, wherein different context model indices are obtained for quantized transform coefficients in different regions of the transform block and a single context index is used for at least one region of the transform block; and selecting for the one or more syntax elements associated with a particular quantized transform coefficient one of several context models based on the determined content model index.

Abstract: This method for up-sampling a point cloud representing a 3D object, comprises: —detecting (2) points belonging to at least one under-sampled region of the point cloud on the basis of at least one desirable sampling rate (K); —obtaining (12), for each detected point, an associated tangent plane; —inserting (14) in the point cloud at least one neighboring point of each detected point if a distance between the neighboring point and the tangent plane associated with the detected point is less than a first threshold.

Abstract: In video coding, a transform can be selected from multiple transform sets. To efficiently implement multiple transforms, a unified architecture of implementing the Discrete Trigonometric Transforms (DTTs) or flipped DTT can be used. In the proposed unified architecture, the relationships between the transforms are utilized. In particular, all transforms can be implemented based on DCT-II, DCT-IV, a reverse order operation, and a sign changing operation for odd elements. The DCT-II can be implemented at a minimum size, and other sizes for DCT-II can be implemented recursively from the minimum size DCT-II and DCT-IV at various sizes. In one example, the multiple transforms are {DCT-II, DST-II, DCT-III, DST-III, DCT-IV, DST-IV}. The relationships between transforms can also be used to guide the design of additional transforms that can be implemented by the unified architecture.