Abstract: A method of video decoding includes retrieving, from a coded video bitstream for a current block encoded in an intra prediction mode, a reference line index indicating a reference line from a plurality of reference lines that include a zero reference line. The method includes determining whether the current block is encoded in a non-angular intra prediction mode. The method includes, in response to the block being encoded in the non-angular intra prediction mode, determining whether the reference line index indicates a non-zero reference line from the plurality of reference lines. The method includes in response to determining that the reference line index is the non-zero reference line, (i) enabling non-angular intra prediction modes for the non-zero reference line, and (ii) decoding the current block with at least one reference sample from the non-zero reference line.

Abstract: Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. An apparatus for video decoding includes processing circuitry that decodes prediction information for a current block in a current picture that is a part of a coded video sequence. The processing circuitry determines whether the current block is coded in an intra block copy (IBC) mode based on the prediction information. Responsive to the current block not being coded in the IBC mode, the processing circuitry determines whether a size of the current block is above a threshold. The processing circuitry determines that the current block is coded in an intra prediction mode based on a determination that the size of the current block is not above the threshold. The processing circuitry reconstructs the current block based on the intra prediction mode.

Abstract: Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. In some examples, an apparatus for video decoding includes receiving circuitry and processing circuitry. For example, the processing circuitry receives a bitstream including bits corresponding to residues of a block in a coded picture and parses the bitstream to extract at least one bit that is indicative of a potential usage of an angular prediction of the block. Further, the processing circuitry determines context for coding information of a secondary transform based on the at least one bit that is indicative of the potential usage of the angular prediction of the block, and decode the bits corresponding to the residues of the block using the secondary transform information that is decoded based on the context.

Abstract: Aspects of the disclosure provide a method and an apparatus for video coding. In some examples, an apparatus includes processing circuitry that determines a plurality of first sub-block motion vectors for a plurality of sub-blocks of a current block, and determines a plurality of second sub-block motion vectors according to the plurality of first sub-block motion vectors and a first target range. The processing circuitry also determines a set of gradient values associated with a current sample location in a current sub-block, determines an adjustment vector associated with the current sample location, and determines a set of adjustment values associated with the current sample location according to the set of gradient values and the adjustment vector. The processing circuitry generates a predicted sample associated with the current sample location according to a combination of a corresponding sample in a reference sub-block and the set of adjustment values.

Abstract: An apparatus for video decoding that includes processing circuitry. The processing circuitry can be configured to receive a coding block having a width of W pixels and a height of H pixels, and partition the coding block into sub processing units (SPUs) each having a width of a lesser of W or K pixels and a height of a lesser of H or K pixels, where K is a dimension of a virtual pipeline data unit (VPDU) having an area of K×K pixels. Each SPU is partitioned into transform units with each transform unit having a maximum allowable transform unit size of M pixels.

Abstract: Aspects of the disclosure provide methods and an apparatus including processing circuitry that decodes coded information of a coding block (CB) in a picture from a coded video bitstream. The coded information indicates a width W and a height H of the CB. The processing circuitry partitions the CB into sub-processing units (SPUs) having a width being a minimum one of W and K and a height being a minimum one of H and K. At least one of the width W and the height H is larger than a processing data unit size K. The processing circuitry determines a partitioning structure to partition the SPUs based on the width, the height, and a maximum transform unit (TU) size M. At least one of the width and the height is larger than M. The processing circuitry partitions each of the SPUs into TUs of M×M based on the partitioning structure.

Abstract: An apparatus for video decoding includes processing circuitry. The circuitry can be configured to determine whether to apply the PROF to an affine coded block, and responsive to a determination to apply the PROF to the affine coded block, perform a PROF process. For example, during the PROF process, a prediction sample I(ij) at a sample location (ij) in the affine coded block can be generated. Spatial gradients g_x (i,j) and g_y (ij) at the sample location (ij) in the affine coded block can be generate. A prediction refinement ?I(ij) based on the spatial gradients g_x (ij) and g_y (i,j) can be generated. The prediction refinement ?I(ij) can added to the prediction sample I(ij) to generate a refined prediction sample. The PROF for affine prediction can be enabled according to a syntax element received at the decoder, or can be enabled by default.

Abstract: A method of decoding video data includes constructing, by a video decoder implemented in processing circuitry, a candidate list of motion vector information for a portion of a current frame. The method includes receiving, by the video decoder, signaling information indicating starting motion vector information of the candidate list of motion vector information, the starting motion vector information indicating an initial position in a reference frame. The method includes refining, by the video decoder, based on one or more of bilateral matching or template matching, the starting motion vector information to determine refined motion vector information indicating a refined position in the reference frame that is within a search range from the initial position. The method includes generating, by the video decoder, a predictive block based on the refined motion vector information and decoding, by the video decoder, the current frame based on the predictive block.

Abstract: Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. In some examples, an apparatus for video decoding includes processing circuitry. The processing circuitry can decode prediction information for a current block in a current picture that is a part of a coded video sequence. The prediction information indicates a prediction mode for the current block and an access order for an affine history-based motion vector predictor (HMVP) buffer. The processing circuitry constructs a motion vector predictor (MVP) list including an affine HMVP candidate from the affine HMVP buffer according to the access order. The processing circuitry can reconstruct the current block based on the MVP list.

Abstract: A method of video decoding performed in a video decoder is provided. In the method, coded information of neighboring blocks of a current block is received from a coded video bitstream. The coded information includes intra prediction information of the neighboring blocks. Intra prediction information of the current block is determined based on the coded information of the neighboring blocks. An intra prediction direction mode is determined based on the intra prediction information of the current block. At least one sample of the current block is reconstructed according to the intra prediction direction mode of the current block.

Abstract: Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. An apparatus for video decoding includes processing circuitry that decodes prediction information for a current block in a current picture that is a part of a coded video sequence. The prediction information indicates a specific inter prediction mode, a position dependent prediction combination (PDPC) process, and a coded residual for the current block. The processing circuitry determines at least one of (i) a partition of the current block to which a transform process is to be applied and (ii) a transform type of the transform process for the current block based on the prediction information. The processing circuitry performs the transform process on the coded residual to generate a decoded residual. The processing circuitry reconstructs the current block based on the decoded residual.

Abstract: Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. In some examples, an apparatus for video decoding includes processing circuitry. The processing circuitry is configured to decode prediction information of a block in a current picture from a coded video bitstream. The prediction information indicates an affine model in an inter prediction mode. The processing circuitry is configured to determine motion vectors of control points of the block according to the affine model. The processing circuitry is configured to determine a motion vector of a sub-block of the block from the determined motion vectors of the control points, one of a width and a height of the sub-block being less than 4. Further, the processing circuitry is configured to reconstruct at least a sample of the sub-block according to the determined motion vector.

Abstract: Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. In some examples, an apparatus for video decoding includes processing circuitry that decodes prediction information for a current block in a current coded picture that is part of a coded video sequence. The prediction information indicates a fractional motion vector for the current block. The processing circuitry determines whether one of a block width and a block height of the current block is below a first threshold. The processing circuitry selects one of an integer motion vector, a first interpolation filter, and a second interpolation filter for the current block when the one of the block width and the block height of the current block is determined to be below the first threshold. The processing circuitry reconstructs the current block based on the selected one of the integer motion vector, the first interpolation filter, and the second interpolation filter.

Abstract: A method for video decoding in a decoder is provided. In the method, transform block signaling information is acquired from a coded video bitstream. A transform type is determined based on the transform block signaling information. A low frequency coefficient of one of a plurality of sub transform units is determined based on the transform type and neighboring sub transform units of the one of the plurality of sub transform units. The plurality of sub transform units is partitioned from a current coding block unit (CU). The current coding block unit is subsequently decoded based on low frequency coefficients of the plurality of sub transform units, where the low frequency coefficients include the low frequency coefficient of the one of the plurality of sub transform units.

Abstract: The disclosure provides methods and apparatuses for video encoding/decoding. An apparatus includes processing circuitry that decodes prediction information for a coding region partially located outside a picture boundary. The processing circuitry determines whether a shared merge list is used for the coding region. Responsive to the shared merge list being used for the coding region, the processing circuitry constructs the shared merge list and reconstructs the coding region based on the shared merge list. Another apparatus includes processing circuitry that decodes prediction information for a current block and examines coding blocks of a collocated block of the current block according to an examination order. A second examined position in the examination order is one of the coding blocks located adjacent to a top-left corner of the collocated block. The processing circuitry determines a TMVP according to the examined coding blocks and reconstructs the current block based on the TMVP.

Abstract: A method and apparatus for encoding or decoding a video sequence includes encoding or decoding the video sequence using a 4:4:4 chroma format, or encoding or decoding the video sequence using a 4:2:2 chroma format, wherein when encoding or decoding the video sequence using the 4:4:4 chroma format, copying an affine motion vector of one 4×4 luma block using an operation other than an averaging operation and associating the affine motion vector to a co-located 4×4 chroma block, and when encoding or decoding the video sequence using the 4:2:2 chroma format, associating each 4×4 chroma block with two 4×4 co-located luma blocks such that an affine motion vector of one 4×4 chroma block is an average of the motion vectors of the two co-located luma blocks.

Abstract: A method of video decoding performed in a video decoder. The method including receiving a coded video bitstream including a current picture. The method further including, performing an inverse quantization on a current block included in the current picture. The method further including performing, after performing the inverse quantization, an inverse transform on the current block. The method further including performing a prediction process on the current block after performing the inverse transform. The method further including, after performing the prediction process on the current block, determining whether a predetermined condition is satisfied. The method further including, in response to determining that the predetermined condition is met, performing an inverse color transform on the current block.

Abstract: Methods, apparatuses, and computer-readable medium are provided for a frame rate up-conversion coding mode, in which an affine motion model is applied when conducting bilateral matching. The frame rate up-conversion coding mode can include generated additional frames from frames provided in a bitstream. In various implementations, bilateral matching includes, for a current block in a frame that is being generated, identifying a first block in a first reference picture a second block in a second reference picture. Affine (e.g., non-linear) motion information can be determined as between the first block and the second block. The current block can be predicted using the affine motion information.

Abstract: Aspects of the disclosure provide methods and an apparatus for video decoding. In some embodiments, the apparatus for video decoding includes processing circuitry. The processing circuitry decodes at least one syntax element from a coded video bitstream. The at least one syntax element is indicative of a block size of a non-square block under reconstruction that has a rectangular shape. The block size includes a first size in a first dimension and a second size in a second dimension. The first size is different from the second size. The processing circuitry predicts a sample of the non-square block based on a first set of intra prediction directions for the non-square block. The first set of intra prediction directions does not include at least one of a second set of intra prediction directions for a square block.

Abstract: An apparatus for video decoding includes processing circuitry configured to determine an affine model for a current block coded with an interweaved affine mode. Based on the affine model, a first prediction block corresponding to a first pattern for partitioning the current block into first sub-blocks and a second prediction block corresponding to a second pattern for partitioning the current block into second sub-blocks can be generated. The first and second prediction blocks include interpolated samples having an intermediate bit-depth larger than an input bit-depth of the current block. Co-located first and samples in the first and second prediction blocks with a precision corresponding to the intermediate bit-depth are weighted averaged to obtain averaged samples. The averaged samples are rounded to the input bit-depth to obtain corresponding third samples in a final prediction block of the current block.