Abstract: A method of video coding a block of a picture includes: obtaining a residual signal resulting from inter- or intra-picture prediction; inferring use of a DCT2 transform core for a sequence of the residual signal; processing the transformation of the block using the inferred transform core.

Abstract: A device for encoding and a device for decoding a picture, respectively, and corresponding methods relating to the field of picture coding are provided. The devices are respectively configured to partition the picture into one or more slices, each slice comprising one or more tiles, and one or more slices holding coded picture data. Further, the devices are configured to encode the one or more slices holding coded picture data, thereby improving coding and decoding of pictures with uncoded buffer space.

Abstract: An apparatus and a method for filtering reconstructed images, in particular, video images, with adaptive multiplicative filters. The efficiency of the filtering operation is increased by restricting the allowable values of the filter coefficients to those that have only a limited number of “ones” in the binary representation.

Abstract: A coding apparatus configured to select an intra prediction mode for a current block, encode the selected intra prediction mode using truncated binary coding every time the selected intra prediction mode is a remaining mode, and encode the selected intra prediction mode using N bits when the selected intra prediction mode is included in a first portion from remaining modes and using N+1 bits when the selected intra prediction mode is included in a second portion of the remaining modes.

Abstract: The present invention relates to the performance of motion vector refinement in a search space for multi-reference inter-prediction. Two or more reference pictures are selected, one of those used for motion vector refinement. Based on an initial estimate of a motion vector to the reference picture for motion vector refinement, a search space in this reference image is constructed. Using template matching, the first motion vector is refined. The second motion vector to another reference picture is calculated using its initial estimate, the initial estimate of the first motion vector and the refined first motion vector.

Abstract: A method and an apparatus for encoding a picture and decoding a bitstream representing a matrix using a neural network is provided. The method includes obtaining a resizing method out of a plurality of resizing methods. The resizing method is applied to resize an input of size S to a size S. The resized input is processed by the neural network, wherein the neural network comprises one or more downsampling layers.

Abstract: The present disclosure relates to motion vector refinement. As a first step, an initial motion vector and a template for the block are obtained. Then, the refinement of the initial motion vector is determined by template matching with said template in a search space. The search space is located on a position given by the initial motion vector and includes one or more fractional sample positions, wherein each of the fractional sample positions belonging to the search space is obtained by interpolation filtering with a filter of a predefined tap-size assessing integer samples only within a window, said window being formed by integer samples accessible for the template matching in said search space.

Abstract: An image processing device for use in an image encoder and/or an image decoder, for deblocking a block edge between a first block and a second block of an image encoded with a block code, is provided. The image processing device comprises a filter for filtering the block edge, configured to, for at least some of the pixels to be filtered, within a deblocking range from the block edge, the deblocking range being perpendicular to the block edge, determine a filtered pixel value from an original pixel value of the pixel and at least one further pixel value, determine a clipping value of the pixel, dependent upon a distance of the pixel from the block edge, and clip the filtered pixel value, using the clipping value resulting in a deblocked pixel value.

Abstract: The present disclosure relates to picture or video encoding and decoding. A picture portion includes a luma component and a chroma component with a resolution lower than a resolution of the luma component. To obtain matching resolution of the luma component and the chroma component, a selection is performed between a down-sampling processing of the luma component and an up-sampling processing of the chroma component. Then, the selected processing is applied to a picture portion. The bitstream is then generated based on the selected processing, and includes encoding the processed picture portion. The selection between chroma up-sampling and luma down-sampling enables adaption of the input picture portion for the desired application. For example, some applications may aim at reducing complexity or bitrate in which case the luma down-sampling may be more favorable, whereas other application may aim at higher quality in which case chroma up-sampling may be more favorable.

Abstract: For picture decoding and encoding of neural-network-based bitstreams, a picture is represented by an input set of samples which is obtained from the bitstream. The picture is reconstructed from output subsets, which are generated as a result of processing the input set L. The input set is divided into multiple input subsets Li. The input subsets are each subject to processing with a neural network having one or more layers. The neural network uses as input multiple samples of an input subset and generates one sample of an output subset. By combining the output subsets, the picture is reconstructed. In particular, the size of at least one input subset is smaller than a size that is required to obtain the size of the respective output subset, after processing by the one or more layers of the neural network.

Abstract: The present disclosure relates to video encoding and decoding, and in particular to handling of chroma subsampled formats in machine-learning-based video coding. Corresponding apparatuses and methods enable the processing for encoding and decoding of a respective picture portion that includes a luma component and a chroma component with a resolution lower than the luma component. In order to handle such different sized luma-chroma channels, the chroma component is up-sampled such that the obtained up-sampled chroma component has a resolution matching the one of the luma component. The luma and the up-sampled chroma component are then encoded into a bitstream. To reconstruct the picture portion, the luma component and an intermediate chroma component matching the resolution of the luma component are decoded from the bitstream, followed by down-sampling the intermediate chroma component. Thus, sub-sampled chroma formats may be handled by an autoencoder/autodecoder framework, while preserving the luma channel.

Abstract: A method of coding implemented by a decoding device or an encoding device, comprising obtaining indication information for a luma position (cbWidth/2, cbHeight/2) of a current coding block, relative to a top-left luma sample position (xCb, yCb) of the current coding block; setting a value of a luma intra prediction mode associated with the current coding block to a first default value, when the indication information indicates that an Intra Block Copy (IBC) mode or palette mode is applied for the luma component at the luma position (cbWidth/2, cbHeight/2), relative to the top-left luma sample position (xCb, yCb) of the current coding block; and obtaining a value of a chroma intra prediction mode based on the value of the luma intra prediction mode of the current coding block.

Abstract: A video processing method, comprising: initializing a HMVP list for a current CTU row when the current CTU is the beginning CTU of a current CTU row; and processing the current CTU row based on the HMVP list. By performing the method, the encoding efficiency and decoding efficiency are improved.

Abstract: A decoding method and a decoder for decoding a current block of a video frame is provided, wherein the decoding method comprises determining a list of Most Probable Modes (MPMs) for the current block. When at least one condition is satisfied, the list of MPMs includes a DC mode, a Vertical mode, a Horizontal mode, an intra prediction mode corresponding to a value of the Vertical mode with a first offset, and an intra prediction mode corresponding to the value of the Vertical mode with a second offset. The decoding method further includes obtaining a MPM flag and a MPM index for the current block from a bitstream of the video, and obtaining an intra prediction mode for the current block for reconstructing the current block.

Abstract: An apparatus and a method for filtering reconstructed images, in particular, video images, with adaptive multiplicative filters. The efficiency of the filtering operation is increased by restricting the allowable values of the filter coefficients to those that have only a limited number of “ones” in the binary representation.

Abstract: A method of decoding of a picture from a video bitstream is disclosed. The video bitstream includes a slice header of a current slice and data representing the current slice. The method comprises: obtaining a parameter used to derive a number of tiles in the current slice from the slice header when a slice address of the current slice is not an address of a last tile in the picture where the current slice located; and reconstructing the current slice using the number of tiles in the current slice and the data representing the current slice.

Abstract: A method of video coding a block of a picture includes: obtaining a residual signal resulting from inter- or intra-picture prediction; inferring use of a DCT2 transform core for a sequence of the residual signal; processing the transformation of the block using the inferred transform core.

Abstract: An apparatus and method for marking availability of a candidate coding block for merge estimation of a current coding block within a coding tree unit, CTU, which includes multiple coding blocks. Initially, the candidate coding block is marked as available. The candidate coding block is marked as unavailable when a predefined location of the candidate coding block is included within an extended merge estimation region, MER. The extended MER includes a current MER in which the current coding block is located and at least a portion of another MER, adjacent to the current MER.

Abstract: A partitioning method comprises determining whether a current block of a picture is a boundary block and whether the size of the current block is larger than a minimum allowed quadtree leaf node size; and if the current block is the boundary block and the size of the current block is not larger than the minimum allowed quadtree leaf node size (MinQTSize), applying forced binary tree (BT) partitioning to the current block. A method comprises making a determination that a current block of a picture is a boundary block and that a size of the current block is less than or equal to a minimum allowed quadtree (QT) leaf node size (MinQTSize); and applying, in response to the determination, forced binary tree (BT) partitioning to the current block.

Abstract: A method and image processing device are provided, including a deblocking filter. The deblocking filter modifies values of at most MA samples of the first image block as first filter output values, the at most MA samples being located at a column of the first image block that is perpendicular to and adjacent to the horizontal block edge; and modifies values of at most MB samples of the second image block as second filter output values, the at most MB samples being located at a column of the second image block that is perpendicular to and adjacent to the horizontal block edge. At most a number MA of sample values of the first image block adjacent to the block edge are modified and at most a number MB of sample values of the second image block adjacent to the block edge are modified, wherein MA<MB.