Abstract: The present invention provides a method for encoding a video signal based on an Edge Adaptive Graph-Based Transform (EA-GBT) including detecting a step edge or a ramp edge from a residual signal; generating a graph signal based on at least one of the step edge or the ramp edge; obtaining an EA-GBT coefficient by performing the EA-GBT for the graph signal; quantizing the EA-GBT coefficient; and entropy-encoding the quantized EA-GBT coefficient.

Abstract: A method of decoding video data includes determining that a current block of the video data is coded in palette mode, determining, between single tree or dual tree partitioning, that the current block is coded with single tree partitioning enabled, determining that the current block is coded in monochrome format, when the current block is coded with single tree partitioning enabled and when the current block is coded in monochrome format, determining that a number of color components used for palette mode decoding the current block is equal to one, and palette mode decoding the current block based on the determined number of color components used for palette mode decoding the current block being equal to one.

Abstract: An example device for decoding video data includes a memory for storing the video data and one or more processors implemented in circuitry and communicatively coupled to the memory. The one or more processors are configured to determine whether a first coding unit (CU) is a skip mode CU, and based on the first CU not being a skip mode CU, determine whether the first CU is encoded using one of an intra mode or a palette mode. The one or more processors are also configured to determine whether the first CU is encoded using the palette mode based on the first CU being encoded using one of the intra mode or the palette mode. The one or more processors are also configured to decode the first CU based on the determination of whether the first CU is encoded using the palette mode.

Abstract: The present invention provides a method for encoding a video signal on the basis of a graph-based separable transform (GBST), the method comprising the steps of: generating an incidence matrix representing a line graph; training a sample covariance matrix for rows and columns from the rows and columns of a residual signal; calculating a graph Laplacian matrix for rows and columns on the basis of the incidence matrix and the sample covariance matrix for rows and columns; and obtaining a GBST by performing eigen decomposition of the graph Laplacian matrix for rows and columns.

Abstract: A video decoder can be configured to determine that a block of video data is encoded without transforming residual data for the block; determine a quantization parameter for the block of video data; based on the determined quantization parameter, determine a range for levels of quantized residual values of the block; divide the range into k intervals, wherein k is an integer value; determine a level for a quantized residual value of the block based on the k intervals by receiving information indicating the level for the quantized residual value is within a particular interval of the k intervals, receiving information indicating a difference value that represents a difference between a reference level value for the particular interval and the level for the quantized residual value of the block, and based on the reference level value and the difference value, determining the level for the quantized residual value.

Abstract: Embodiments are directed to systems and methods of using rice code in video coding. In one embodiment includes a method of encoding or decoding video data, e.g., on a video encoder or decoder. The method includes determining available residual coefficients neighboring a current position in a transform unit of video data and determining a sum of the available residual coefficients. The method further includes modifying the sum based on the number of available residual coefficients and determining a rice parameter based on the modified sum. The method further includes encoding or decoding a syntax element of video data based on the determined rice parameter.

Abstract: An example method includes decoding, from a coded video bitstream, an explicitly defined scaling list; determining, based on values of one or more syntax elements decoded from a sequence parameter set (SPS) of the coded video bitstream, a set of block types to which the explicitly defined scaling list is eligible for application; and applying the explicitly defined scaling list to a block included in the set of block types.

Abstract: A video decoder can be configured to determine a predicted luma quantization parameter (QP) for a luma component of a coding unit; receive, in the bitstream of encoded video data, first syntax indicating a luma delta QP value for the luma component; determine a QP value for the luma component based on the predicted luma QP and the luma delta QP value; determine a predicted chroma QP for a chroma component of the coding unit; receive, in the bitstream of encoded video data, second syntax indicating a chroma delta QP value for the chroma component of the coding unit; and determine a QP value for the chroma component of the coding unit based on the predicted chroma QP and the chroma delta QP value.

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: Examples of block-level signaling of quantization parameter offsets is described. Such block-level signaling of quantization parameter offsets provides block level flexibility to determine a more precise chroma quantization parameter (QP) for a chroma block. With the block-level quantization parameter offset signaling described in this disclosure, there is more flexibility in defining the chroma QP, resulting in more accurate determination of chroma QP on a chroma block-by-chroma block basis.

Abstract: A method of decoding video data includes receiving encoded data for a current block of the video data, the current block comprising one or more escape mode encoded samples and decoding, from the encoded data, a value indicating that the current block includes the one or more escape mode encoded samples. The method further includes, in response to determining that the value indicates that the current block includes the one or more escape mode encoded samples and that a current tree type for the current block is not dual tree chroma, decoding an absolute value for a luma delta quantization parameter for the current block and a sign for the luma delta quantization parameter. The method further includes reconstructing the current block based on the absolute value for the luma delta quantization parameter for the current block and the sign for the luma delta quantization parameter.

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 includes a memory configured to store at least a portion of an encoded video bitstream; and one or more processors that are implemented in circuitry and configured to: determine, based on a parameter of a first block of video data, a maximum number of entries to be used for palette-mode coding of the current block; generate, based on the determined maximum number of entries and based on a palette predictor, a palette for the first block of video data, the palette including one or more entries each including a palette index that is associated with a color value; decode, from the encoded video bitstream and for the first block of video data, index values for samples of the first block that identify entries in the palette; and reconstruct, based on the index values, the samples of the first block.

Abstract: A method of decoding video data includes receiving a value indicating that a lossless mode is enabled for a block of the video data and, in response to determining that the value indicates that the lossless mode is enabled for the block of the video data, determining a maximum size for a lossless-coded transform block of the block of the video data is set to a maximum scanning size of the non-lossless coding block. The method further includes inverse scanning residual values for the block of the video data based on the maximum size for the lossless-coded transform block to generate a residual block for the block of the video data and reconstructing the block of the video data based on the residual block.

Abstract: A video encoder derives a minimum allowed base quantization parameter for video data based on an input bitdepth of the video data, determines a base quantization parameter for a block of the video data based on the minimum allowed base quantization parameter, and quantizes the block of video data based on the base quantization parameter. In a reciprocal fashion, a video decoder derives a minimum allowed base quantization parameter for the video data based on an input bitdepth of the video data, determines a base quantization parameter for a block of the video data based on the minimum allowed base quantization parameter, and inverse quantizes the block of video data based on the base quantization parameter.

Abstract: Systems, methods, and computer-readable storage media for maintaining palette predictors for palette coding are described. An example method can include determining a current palette coding block of a single tree coded slice of a picture is encoded according to a local dual tree; determining, after an update of a palette predictor associated with the current palette coding block, a first number of palette predictor entries for a first image component of the current palette coding block and a second number of palette predictor entries for a second image component of the current palette coding block; determining the first number of palette predictor entries is greater than the second number of palette predictor entries; and based on the first number being greater than the second number, modifying the updated palette predictor to include a same number of palette predictor entries for the first and second image component.

Abstract: A video decoder may divide a current coding unit (CU) of video data into a plurality of index groups. The video decoder may decode syntax elements common to all of the index groups and then separately and sequentially decode syntax elements for each of the index groups. By first decoding the syntax elements used by all the index groups and then separately grouping the decoding of the syntax elements for the index groups, the video decoder may begin the construction process of some samples of the current CU without having to wait to complete decoding of all of the syntax elements of the current CU. As such, the techniques of this disclosure may decrease the amount of time required and/or the delay introduced by the decoding process.

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 method includes decoding, from a coded video bitstream, an explicitly defined scaling list; determining, based on values of one or more syntax elements decoded from a sequence parameter set (SPS) of the coded video bitstream, a set of block types to which the explicitly defined scaling list is eligible for application; and applying the explicitly defined scaling list to a block included in the set of block types.

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.