Abstract: An example video decoder is configured to decode a first value for a first syntax element of a current block of video data, the first value indicating that the current block is encoded using an intra-prediction mode; after decoding the first value, decode a second value for a second syntax element of the current block, the second value indicating that the current block is encoded using intra mapping mode. In the intra mapping mode, the video decoder is configured to generate a prediction block for the current block using the intra-prediction mode and decode a residual block. To decode the residual block, the video decoder is configured to determine predictors for quantized residual values of the residual block and map decoded mapping values to the quantized residual values using the predictors. The video decoder combines the prediction block with the residual block to decode the current block.

Abstract: An example device for coding video data includes a memory configured to store video data; and one or more processors implemented in circuitry and configured to: construct a motion vector predictor candidate list for a current block of the video data, the motion vector predictor candidate list identifying one or more blocks that are non-adjacent to the current block, each of the non-adjacent blocks being in a coding tree unit (CTU) including the current block or a line buffer including the current block; select a motion vector predictor from one of the blocks that is non-adjacent to the current block and in the motion vector predictor candidate list; and code motion information of the current block using the motion vector predictor.

Abstract: Techniques for coding coefficients in a residual block are described. A video coder (e.g., video encoder or video decoder) may code (e.g., encode or decode), in an interleaving manner, coefficient information on a coefficient-by-coefficient basis for coefficients in a residual block of a current block of the video data in a first pass, wherein the coefficient information for a coefficient includes one or more of a significance flag indicating whether a value of the coefficient is not zero, a parity flag indicating whether the value of the coefficient is odd or even, a sign flag indicating whether the value of the coefficient is positive or negative, and one or more greater than flags indicating whether an absolute value of the coefficient is greater than respective threshold values, and after the first pass, code remainder information for coefficients in the residual block of the current block in a second pass.

Abstract: An example method includes dividing a current coding unit (CU) of video data into a plurality of index groups, the current CU of video data coded using a palette mode; parsing syntax elements for a first index group of the plurality of index groups; after parsing the syntax elements for the first index group, parsing syntax elements for a second index group of the plurality of index groups; and reconstructing the current CU of video data based on the syntax elements for the first index group and the syntax elements for the second index group.

Abstract: A video decoder configured to receive a first syntax element indicating if any coding group (CG) of a plurality of CGs includes at least one non-zero coefficient, wherein the plurality of CGs includes a luma CG and at least one chroma CG; in response to the first syntax element indicating that a CG of a plurality of CGs includes at least one non-zero coefficient, receive, for each CG of the plurality of CGs, a flag indicating if a corresponding CG of the plurality of CGs includes at least one non-zero coefficient; and for a CG with a corresponding flag indicating that the CG includes at least one non-zero coefficient, receive additional syntax indicating values for coefficients of the CG.

Abstract: This disclosure describes determining triangular prediction blocks for a current block partitioned in a triangle mode. A video coder may determine indices in a motion vector predictor list to identify motion vector predictors used to determine the triangular prediction block. If a first index value in the motion vector predictor list for a first triangular prediction block is less than a second index value in the motion vector predictor list for a second triangular prediction block, the signaled or received value for the second triangular prediction block may be the second index value reduced by an offset.

Abstract: The present invention provides a method for encoding a video signal on the basis of a graph-based lifting transform (GBLT), comprising the steps of: detecting an edge from an intra residual signal; generating a graph on the basis of the detected edge, wherein the graph includes a node and a weight link; acquiring a GBLT coefficient by performing the GBLT for the graph; quantizing the GBLT coefficient; and entropy-encoding the quantized GBLT coefficient, wherein the GBLT includes a partitioning step, a prediction step, and an update step.

Abstract: Deblocking is a step in video coding for removing distortions that may result from dividing a video frame into blocks, and encoding the video frame based on the blocks. Techniques described herein can include determining the activity in neighboring blocks along the boundary of the blocks, where the activity measures smoothness or complexity of pixels in the boundary area. An average of the activity can then be determined, as well a difference in the activity between the left block and the right block. The average activity and the difference in activity can then be used to determine a classification for the boundary area. The classification can further be used to select a filter to apply to the pixels in the boundary area. Once the filter have been applied, the blocks can be added to a reconstructed video frame.

Abstract: Systems and techniques for intra-block copy (IBC) prediction in processing video data include the use of one or more virtual search areas (VSAs) which can be generated to include one or more references to one or more pixels stored in a physical memory. The one or more VSAs can provide references to additional reconstructed sample values that are derived from previously decoded blocks without incurring physical memory use for storage of the additional reconstructed samples. A search area for performing the IBC prediction for a current block of the video data can be extended to include the one or more VSAs. Extending the search area to include the one or more VSAs provides the IBC prediction with additional search area for finding one or more prediction blocks or prediction samples without having to utilize physical memory to store the additional reconstructed samples from previously decoded blocks.

Abstract: Embodiments include systems and methods of generating merge candidates for an inter-prediction mode of a video block. In particular, embodiments include methods of generating spatial-temporal motion vector predictor candidates. Embodiments may include video encoders and video decoders.

Abstract: This disclosure describes determining triangular prediction blocks for a current block partitioned in a triangle mode. A video coder may determine indices in a motion vector predictor list to identify motion vector predictors used to determine the triangular prediction block. If a first index value in the motion vector predictor list for a first triangular prediction block is less than a second index value in the motion vector predictor list for a second triangular prediction block, the signaled or received value for the second triangular prediction block may be the second index value reduced by an offset.

Abstract: The present invention provides a method for decoding a video signal using a graph-based transform including receiving a generalized graph signal including a graph parameter set; obtaining a graph-based transform kernel of a transform unit based on the graph parameter set and a predetermined penalty function; and decoding the transform unit using the graph-based transform kernel.

Abstract: A method for encoding a raw lenselet image includes a receiving phase, wherein at least a portion of a raw lenselet image is received, the image including a plurality of macro-pixels, each macro-pixel having pixels corresponding to a specific view angle for the same point of a scene, and an output phase, wherein a bitstream having at least a portion of an encoded lenselet image is outputted. The method has an image transform phase, wherein the pixels of said raw lenselet image are spatially displaced in a transformed multi-color image having a larger number of columns and rows with respect to the received raw lenselet image, wherein dummy pixels having undefined value are inserted into the raw lenselet image and wherein the displacement is performed so as to put the estimated center location of each macro-pixel onto integer pixel locations.

Abstract: This disclosure describes examples of extending the number of available discrete cosine transform (DCT) and discrete sine transform (DST) for encoding and decoding. A video coder may determine one or more transforms or inverse transforms to apply from a set of transforms or inverse transforms that includes DCT-2 or inverse DCT-2, DST-7 or inverse DST-7, DST-8 or inverse DST-8, DCT-3 or inverse DCT-3, DST-2 or inverse DST-2, DST-3 or inverse DST-3, DCT-4 or inverse DCT-4, DST-4 or inverse DST-4, DST-5 or inverse DST-5, DST-6 or inverse DST-6, and identity transform an inverse identity transform (IDT).

Abstract: An example device for coding video data includes a memory configured to store video data; and one or more processors implemented in circuitry and configured to: construct a motion vector predictor candidate list for a current block of the video data, the motion vector predictor candidate list identifying one or more blocks that are non-adjacent to the current block, each of the non-adjacent blocks being in a coding tree unit (CTU) including the current block or a line buffer including the current block; select a motion vector predictor from one of the blocks that is non-adjacent to the current block and in the motion vector predictor candidate list; and code motion information of the current block using the motion vector predictor.

Abstract: An example device for decoding video data includes a memory configured to store video data; and a processor implemented in circuitry and configured to decode a truncated unary codeword representing a multiple transform (MT) scheme for a current block of the video data to determine the MT scheme; apply the MT scheme to transform coefficients of the current block to produce residual data for the current block of video data; and decode the current block using the residual data. The MT scheme may include a plurality of transforms, such as a horizontal transform and a vertical transform, a primary transform and a second transform, or any combination of separable and/or non-separable transforms. Thus, a single truncated unary codeword may represent the entire MT scheme, that is, each of a plurality of transforms of the MT scheme.

Abstract: Embodiments include techniques in video coding for deriving motion vectors or motion vector predictors for a current coding or prediction unit based on multiple spatial neighbors. For example, the motion vector or motion vector predictors may be derived as the weighted combination of motion vectors of multiple spatial neighbors. Alternatively, or additionally, motion vectors or motion vector predictors for an inter-prediction mode may be generated from respective MVs of two spatially neighboring blocks that are located asymmetrically to the current PU.

Abstract: A method of decoding video data comprising performing a prediction process for one or more neighboring blocks of video data that are neighboring a current block of video data to obtain prediction pixel values for neighboring pixels of the current block of video data, deriving a template for the current block of video data using the prediction pixel values, performing a decoder-side motion vector derivation technique using the derived template to derive a motion vector for the current block of video data, and decoding the current block of video data using the derived motion vector.

Abstract: Deblocking is a step in video coding for removing distortions that may result from dividing a video frame into blocks, and encoding the video frame based on the blocks. Techniques described herein can include determining the activity in neighboring blocks along the boundary of the blocks, where the activity measures smoothness or complexity of pixels in the boundary area. An average of the activity can then be determined, as well a difference in the activity between the left block and the right block. The average activity and the difference in activity can then be used to determine a classification for the boundary area. The classification can further be used to select a filter to apply to the pixels in the boundary area. Once the filter have been applied, the blocks can be added to a reconstructed video frame.

Abstract: Performing a graph-based prediction using a graph signal can be performed using a method that includes obtaining a context signal; generating a graph signal based on a graph parameter set; obtaining a graph-based transform matrix based on the graph signal, wherein the graph-based transform matrix includes an eigenvector; obtaining a prediction vector using an optimal transform vector calculated through an optimization function; and generating a prediction signal using the prediction vector, where the optimization function has the context signal, an eigenvalue of a graph Laplacian matrix and the eigenvector as a variable. Accordingly, a prediction value may be obtained with reduced complexity and the prediction performance may be improved.