Abstract: Aspects of the disclosure provide a method and an apparatus including processing circuitry that determines, based on a syntax element in a coded video bitstream, that a current block including a plurality of subblocks is coded in a subblock-based temporal motion vector prediction (SbTMVP) mode. Motion vector offset (MVO) information indicating an MVO is received. The MVO indicates a motion offset of a displacement vector (DV) used to adjust a location of a collocated block in a collocated reference picture. An updated DV of the current block is determined based on the DV and the MVO. SbTMVP information of a respective subblock in the plurality of subblocks is derived based on motion information of a corresponding subblock in the collocated block indicated by the updated DV. The plurality of subblocks in the SbTMVP mode is reconstructed based on the SbTMVP information of the subblock in the plurality of subblocks.

Abstract: Aspects of the disclosure provide a method and an apparatus for video decoding. The apparatus includes processing circuitry receiving prediction information of a plurality of blocks in a current picture from a coded video bitstream. The processing circuitry determines, based on the prediction information, whether at least one of a decoder-side motion vector refinement (DMVR) mode or a bi-directional optical flow (BDOF) mode is allowed for the plurality of blocks. If the DMVR mode or the BDOF mode is allowed for the plurality of blocks, the processing circuitry determines that a plurality of merge with motion vector difference (MMVD) merge flags indicating whether a MMVD mode is applied to the plurality of blocks, respectively, is inferred as false for the plurality of blocks. If the plurality of MMVD merge flags is inferred as false, the processing circuitry reconstructs each block in the plurality of blocks without applying the MMVD mode.

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 receives a coded video bitstream including a current picture. The current picture includes a current block. The processing circuitry determines, based on decoded information from the coded video bitstream, that the current block in the current picture is coded in an affine bi-prediction mode. The current block is predicted by a plurality of control point motion vectors. The processing circuitry refines the plurality of control point motion vectors by applying bilateral matching motion refinement, and reconstructs the current block according to the refined plurality of control point motion vectors associated with the current block.

Abstract: Aspects of the disclosure provide a method and an apparatus including processing circuitry that obtaining prediction information indicating whether a current block is coded in a subblock-based temporal motion vector prediction (SbTMVP) mode. If the current block is coded in the SbTMVP mode, whether a subblock in a plurality of subblocks of the current block is bi-predicted is determined. If the subblock is bi-predicted, motion information of the subblock is determined based on the SbTMVP mode. At least one of (i) a bilateral matching (BM)-based motion vector (MV) refinement and (ii) a bi-directional optical flow (BDOF) mode is applied to the subblock to refine the motion information of the subblock. The current block is reconstructed based on refined motion information corresponding to one or more subblocks in the plurality of subblocks. The refined motion information corresponding to the one or more subblocks includes the refined motion information of the subblock.

Abstract: Method, apparatus, and non-transitory storage medium for coding and decoding video data using temporal motion vector prediction (TMVP) is provided. The method may include receiving video bitstream comprising one or more pictures; determining that the one or more pictures are to be predicted in a regular merge mode or an adaptive motion vector prediction (AMVP) mode. A displacement vector associated with a current block in a current picture is obtained, the displacement vector being signaled in the video bitstream to identify a reference block in the current picture. A TMVP candidate list comprising the motion information is generated and a motion vector for the current block using the TMVP candidate list is derived. Then the current block is decoded using the derived motion vector for prediction in the regular merge mode or the adaptive motion vector prediction (AMVP) mode.

Abstract: The apparatus includes processing circuitry that receive a bitstream including a picture. The processing circuitry applies one or more first fixed filters with constant filter coefficients to samples in the picture to obtain one or more respective first filtered outputs of the samples in the picture. Subsequent to applying the one or more first fixed filters, the processing circuitry applies one or more second adaptive filters with changeable coefficients to the one or more first filtered outputs to obtain a second filtered sample of a current sample in the samples and decodes the picture based at least on the second filtered sample of the current sample in the picture. Each coefficient of the second adaptive filter can be applied to a corresponding one of the one or more first filtered outputs.

Abstract: Method, apparatus, and non-transitory storage medium for fusing sub-block motion vector predictors into one sub-block motion vector predictor during video coding and decoding is provided. The method may include deriving a first displacement vector for a sub-block of a current block identifying a co-located sub-block of a co-located picture, and based on the identified co-located sub-block, determine whether the co-located sub-block overlaps with one or more sub-blocks associated with a motion field grid in the co-located picture. Based on determining that the co-located sub-block overlaps with the one or more sub-blocks, the method may include, retrieving two or more sub-block motion vectors respectively associated with the one or more sub-blocks. A final motion vector predictor for the sub-block of the current block may be derived based on the two or more sub-block motion vectors retrieved.

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 receives a video bitstream including a current block, and determines a candidate list that includes a plurality of motion vector (MV) candidates for predicting the current block. The processing circuitry modifies the plurality of MV candidates in the candidate list according to a motion information based diversity assessment of the plurality of MV candidates. The modifying the plurality of MV candidates prioritizes a subset of MV candidates with a larger difference in motion information. The processing circuitry decodes, from the video bitstream, an index indicating a selected MV candidate from the modified candidate list, and reconstructs the current block based on the selected MV candidate.

Abstract: Processing circuitry receives a video bitstream and obtains prediction information of a current block in a current picture from the video bitstream. The prediction information is indicative of whether the current block is to be predicted in an inter prediction mode. In response to the current block being predicted in the inter prediction mode, the processing circuitry determines a merge candidate from a merge candidate list, and determines an inter prediction direction based on a syntax element signaled in the video bitstream. The inter prediction direction signaled separately from the merge candidate is one of a first uni-prediction from a first reference picture list, a second uni-prediction from a second reference picture list, and a bi-prediction from the first reference picture list and the second reference picture list. The processing circuitry determines a motion vector, and reconstructs the current block based on the inter prediction direction and the motion vector.

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. The processing circuitry extracts, from a bitstream, a signal indicative of an application of a template matching based block vector refinement for coding a current block in a current picture referencing (CPR) mode. The processing circuitry derives a first refined block vector associated with the current block according to the template matching based block vector refinement. The first refined block vector includes a first block vector refinement offset applied on a first block vector associated with the current block. The processing circuitry reconstructs the current block according to a first reference block in a same picture as the current block, the first reference block being indicated by the first refined block vector.

Abstract: Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. In some examples, processing circuitry receives a coded video bitstream including a current picture. The current picture includes a chroma block in a chroma separate tree, the chroma block being collocated in a same luma area with one or more luma blocks. The processing circuitry decodes, from the coded video bitstream, a syntax element that indicates a current picture referencing (CPR) mode for the chroma block, and determines, in response to the CPR mode, a chroma block vector for the chroma block according to one or more luma block vectors associated with the one or more luma blocks. The chroma block vector indicates a reference chroma block in the current picture. The processing circuitry reconstructs the chroma block based on the reference chroma block in the current picture.

Abstract: Aspects of the disclosure provide a method and an apparatus for video decoding. The apparatus includes processing circuitry. The processing circuitry applies an intra prediction mode with a multiple reference line (MRL) prediction to a current block. For each weight candidate combination including a respective first weight candidate and a respective second weight candidate in a plurality of weight candidate combinations, a subset of samples in the current block is predicted using intra prediction fusion that is based on a first reference line weighted by the respective first weight candidate and a second reference line weighted by the respective second weight candidate. The subset of samples includes top samples in a top-most row and left samples in a left-most column. A gradient cost is determined based on the predicted subset of samples and reconstructed samples outside the current block. A weight candidate combination is selected based on the gradient costs.

Abstract: Aspects of the disclosure provide a method and an apparatus for video decoding. The apparatus includes processing circuitry that receives a coded bitstream comprising a first block in a current picture. The processing circuitry obtains prediction information indicating whether the first block is coded in an intra template matching prediction (IntraTMP) mode. If the IntraTMP mode is applied to the first block, the first block is reconstructed based on a prediction block within a reconstructed search area in the current picture. A reference template of the prediction block is matched to a current template of the first block in the IntraTMP mode. An IntraTMP-based block vector BVIntraTMP of the first block is stored. The IntraTMP-based block vector indicates a position displacement between the current template of the first block and the reference template of the prediction block. A second block is reconstructed based on the stored IntraTMP-based block vector.

Abstract: Aspects of the disclose provide methods and an apparatus for video and/or image coding. The apparatus includes processing circuitry that receives a bitstream including a plurality of pictures. The processing circuitry determines an initial motion vector (MV) associated with a motion compensation padding (MCP) block according to motion information of a boundary block located at a picture boundary of a picture in the plurality of pictures. The boundary block is located in the picture. The MCP block is located in an MCP area outside of the picture and adjacent to the picture boundary. The initial MV has a fractional precision. The processing circuitry generates a final MV associated with the MCP block based on the initial MV. The final MV has an integer precision. The processing circuitry reconstructs, according to the generated final MV having the integer precision, at least a sample in the MCP block.

Abstract: A method performed by a video decoder includes receiving a coded video bitstream including a current picture that includes at least one block. The method includes determining that the at least one block is to be predicted in a reconstruction-reordered intra block copy (RR-IBC) mode. The method includes obtaining a syntax element from the at least one block, the syntax element indicating a flip mode. The method includes determining whether reconstruction flip is applied to the at least one block. The method includes, in response to determining the reconstruction flip is applied to the at least one block, predicting a flip pattern for the at least one block based on neighboring reconstruction samples of the at least block and a corresponding reference block of the at least one block. The method further includes decoding the at least one block based on the flip mode and the predicted flip pattern.

Abstract: Processing circuitry receives a video bitstream comprising a current coding block in a picture coded in a template-based multiple reference line intra prediction (TMRL) mode. The processing circuitry determines combinations of reference lines and intra prediction modes for the current coding block. A first combination in the combinations includes a first reference line and a first intra prediction mode. For the first combination, the processing circuitry calculates template entry delta values respectively associated with entries of a template of the current coding block based on the first reference line and the first intra prediction mode, and calculates a first template matching cost value by unequal weighting of the template entry delta values.

Abstract: A method performed by a video decoder includes receiving a coded video bitstream that includes a current picture with at least one block located at a boundary of the current picture. The method includes determining whether boundary filtering is enabled for the at least one block based on a syntax element in the received coded video stream. The method further includes, based on a determination that the boundary filtering is enabled: filtering one or more boundary samples corresponding to the at least one block to generate one or more filtered samples, and decoding the at least one block based on the generated one or more filtered samples. The method further includes based on a determination that the boundary filtering is not enabled, decoding the at least one block without filtering the one or more boundary samples.

Abstract: In a method, coded information of a current block in a current picture of a video is received from a coded video bitstream. The coded information indicates that the current block is partitioned into at least a first partition and a second partition based on a geometric partition mode (GPM). The first partition is associated with an intra block copy (IBC) prediction mode, and the second partition is associated with an intra prediction mode. Prediction mode information for a first subblock of a plurality of subblocks of the current block is stored. The prediction mode information includes one of a DC mode, a Planar mode, and an intra prediction mode based on whether the first subblock is associated with one of the IBC prediction mode, the intra prediction mode, and both the IBC prediction mode and the intra prediction mode.

Abstract: Aspects of the disclosure provide a method and an apparatus including processing circuitry that decodes a current block in a current picture with a subblock-based temporal motion vector prediction (SbTMVP) mode. A first collocated block in a first collocated picture is determined based on a first displacement vector candidate of the current block corresponding to a first SbTMVP candidate. The processing circuitry determines first motion information of a current template of the current block based on one or more pieces of motion information of the first collocated block or a neighboring block of the first collocated block. The processing circuitry determines one of a first reference template and a first subblock reference template in a first reference picture based on the first motion information and determines a first template matching cost based on the current template and the one of the first reference template and the first subblock reference template.

Abstract: A feature value is determined based on at least one of (i) neighboring reconstructed chroma samples of a current chroma block and (ii) neighboring reconstructed luma samples of a luma block that is collocated with the current chroma block. Chroma samples of the current chroma block and luma samples of the luma block that is collocated with the current chroma block are grouped into a plurality of groups based on a threshold of the feature value. Each of the plurality of groups includes a respective chroma sample and a respective luma sample. A respective cross-component prediction mode is determined for each of the plurality of groups by comparing the respective chroma sample and the respective luma sample of each respective group to the determined feature value. The current chroma block is reconstructed based on the determined cross-component prediction modes of the plurality of groups.