Abstract: A method of decoding video data including receiving video data including coded representations of syntax elements performing inverse binary arithmetic coding on the coded representations of the syntax elements to obtain bins of the syntax elements, inverse binarizing the bins of the syntax elements to obtain the syntax elements, and decoding the video data based on the syntax elements. Performing the inverse binary arithmetic coding includes determining a probability for a particular coded representation of the coded representations, normalizing the probability for the particular coded representation using right bit shifts to create a normalized probability, determining a product of the normalized probability and a range for the particular coded representation, and updating a range of a least probable symbol for the particular coded representation using the determined product.

Abstract: Techniques are described in which a decoder is configured to inverse quantize a first coefficient block and apply a first inverse transform to at least part of the inverse quantized first coefficient block to generate a second coefficient block. The first inverse transform is a non-separable transform. The decoder is further configured to apply a second inverse transform to the second coefficient block to generate a residual video block. The second inverse transform converts the second coefficient block from a frequency domain to a pixel domain. The decoder is further configured to form a decoded video block, wherein forming the decoded video block comprises summing the residual video block with one or more predictive blocks.

Abstract: Disclosed herein is a method of encoding a video signal, comprising receiving an original video signal; comparing the original video signal with available reconstructed signals; determining a correction signal based on a result of the comparison; and generating a transform-coded correction signal to be transmitted for a signal reconstruction.

Abstract: Disclosed herein is a method of performing an arithmetic decoding for data symbols, comprising: creating a decoding table index; obtaining an upper bound value and a lower bound value of a ratio between an interval length and a point within an interval assigned to a symbol from a ROM table; obtaining initial values for a bisection search from a RAM table based on the upper bound value and the lower bound value; and searching a value of sequence in the interval, wherein the interval is determined based on the initial values.

Abstract: Disclosed is a method for encoding a video signal using parallel implementations, including generating data symbols to be encoded, encoding 1st data symbols being in a base segment, copying 2nd data symbols being in another segment to a buffer, and encoding in parallel the 2nd data symbols being in the another segment.

Abstract: A method of decoding video data comprising receiving a block of video data encoded using a position dependent intra prediction combination (PDPC) mode, the block of video data having a non-square shape defined by a width and a height, determining one or more PDPC parameters based on one or more of the width or the height of the block of video data, and decoding the block of video data using the PDPC mode and the determined PDPC parameters.

Abstract: An example method of decoding video data includes determining, by a video decoder and based on syntax elements in an encoded video bitstream, a plurality of values for a current block of the video data; performing, by the video decoder, a multi-pass non-separable inverse transformation on the plurality of values to derive residual data that represents pixel differences between the current block of the video data and a predictive block of the video data; and reconstructing, by the video decoder, the current block of the video data based on the residual data and the predictive block of the video data. In some examples, performing a pass of the multi-pass non-separable inverse transformation includes performing a plurality of Givens orthogonal transformations.

Abstract: Techniques are described of using Position Dependent Intra Prediction Combination (PDPC). A video coder such as a video encoder or a video decoder utilizes PDPC in cases where a current block intra mode predicted using an angular intra prediction mode.

Abstract: A device may perform a first prediction process for a first block of video data to produce a first residual. The device may apply a first transform process to the first residual to generate first transform coefficients for the first block of video data and encode the first transform coefficients. The device may perform a second prediction process for a second block of video data to produce a second residual. The device may determine that a second transform process, which includes the first transform process and at least one of a pre-adjustment operation or a post-adjustment operation, is to be applied to the second residual. The device may apply the first transform process and the pre- or post-adjustment operation to the second residual to generate second transform coefficients for the second block. The coding device may code the first and second transform coefficients.

Abstract: A device for decoding video data can be configured to perform a multi-pass inverse transformation on a plurality of values to derive residual data that represents pixel differences between a current block of video data and a predictive block of the video data, wherein to perform a pass of the multi-pass inverse transformation, the device is configured to determine at least two matrices, wherein the at least two matrices comprise a first matrix and a second matrix; determine at least two vectors, wherein the at least two vectors comprise a first vector and a second vector; and perform at least two matrix-vector computations, wherein the at least two matrix-vector computations comprise a first matrix-vector computation based on the first matrix and the first vector and a second matrix-vector computation based on the second matrix and the second vector.

Abstract: Techniques are described to improved video intra prediction using position-dependent prediction combination in video coding. In High Efficiency Video Encoding a set of 35 linear predictors are used for doing intra coding and prediction can be computed from either a nonfiltered or a filtered set of neighboring “reference” pixels, depending on the selected predictor mode and block size. Techniques of this disclosure may use a weighted combination of both the nonfiltered and filtered set of reference pixels to achieve better compression via improved prediction and therefore small residual, enable effective parallel computation of all sets of prediction values, and maintain low complexity via applying filtering only to a set of reference pixels and not to predicted values themselves.

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.

Abstract: A method for decoding a video signal using a graph-based transform, where the method includes: receiving a template index for a target unit from the video signal, wherein the template index indicates a graph-based transform template to be applied to the target unit; deriving a graph-based transform matrix for the target unit corresponding to the template index; and decoding the target unit based on the graph-based transform matrix. In some scenarios, this enables efficient compression of inter-predicted residual blocks by using graph-based transform templates. The graph-based transform template may enable adaptive transform selection, thus achieving improved coding gain. Further, by defining a graph-based transform template or a template index, coding with a low-complexity is enabled that can reduce the number of bits to be transmitted to the decoder.

Abstract: As part of a video encoding or decoding process, a device applies a transformation to input data elements to derive output data elements for a current block. The transformation comprises a sequence of vector transformations. For each respective vector transformation of the sequence of vector transformations other than a first vector transformation of the sequence of vector transformations, input values for the respective vector transformation comprise output values of the respective previous vector transformation of the sequence of vector transformations. Each respective vector transformation of the sequence of vector transformations further takes, as input, a respective parameter vector for the respective vector transformation, the respective parameter vector for the respective vector transformation comprising one or more parameters.

Abstract: Disclosed herein is a method of processing a graph-based signal using a geometric primitive, comprising: specifying the geometric primitive to be used for calculating an edge weight; obtaining a parameter for each of the geometric primitive; calculating an edge weight for each of edges within the image based on the parameter; and encoding the image based on the edge weight.

Abstract: A device determines a Compact Multi-Pass Transform (CMPT) from a plurality of CMPTs. Additionally, the device decompresses CMPT parameters for the CMPT. In instances where the device decodes video data, the device applies the CMPT to a coefficient block to reconstruct a residual block and decodes, based on a predictive block and the residual block, a current block of a picture of the video data. In instances where the device encodes video data, the device applies the CMPT to a residual block to construct a coefficient block and generates for output information indicating coefficient values for the coefficient block.

Abstract: A method of decoding video data includes receiving, by processing circuitry, a video bitstream including encoded representations of one or more syntax elements of a coded unit and initializing, by the processing circuitry, a respective probability state for each bin of a plurality of bins for the one or more syntax elements based on a comparison of a parameter associated with the coded unit and a respective threshold of a plurality of thresholds. The method further includes performing, by the processing circuitry, inverse binary arithmetic coding on the encoded representations of the one or more syntax elements to obtain each bin of the plurality of bins using a respective probability state for the bin, inverse binarizing, by the processing circuitry, the plurality of bins to obtain the one or more syntax elements, and decoding, by the processing circuitry, the video data based on the one or more syntax elements.

Abstract: A video coder may generate a predictor block using an intra prediction mode. As part of generating the predictor block, the video coder may, for each respective sample in a set of samples in the predictor block, determine, based on an initial value of the first weight and a distance between the respective sample and a first boundary of the predictor block, a value of the first weight for the respective sample. Additionally, the video coder may determine, based on the initial value of the second weight and a distance between the respective sample and a second boundary of the predictor block, a value of the second weight for the respective sample. The video coder may also determine a primary value for the respective sample. The video coder may then determine a secondary value for the respective sample based on the first weight, second weight, and the primary value.

Abstract: A video decoder can be configured to generate a first bin stream by, for at least one bin of the first bin stream, determining a first probability estimation for the at least one bin of the first bin stream based on a first set of parameters and generate a second bin stream by, for at least one bin of the second bin stream, determining a second probability estimation for the at least one bin of the second bin stream based on a second set of parameters that are different parameters than the first set of parameters.

Abstract: Techniques are described in which a decoder is configured to receive an input data block and apply an inverse non-separable transform to at least part of the input data block to generate an inverse non-separable transform output coefficient block. The applying the inverse non-separable transform comprises assigning a window, assigning a weight for each position inside the assigned window, and determining the inverse non-separable transform output coefficient block based on the assigned weights. The decoder is further configured to forming a decoded video block based on the determined inverse non-separable transform output coefficient block, wherein forming the decoded video block comprises summing the residual video block with one or more predictive blocks.