Abstract: Processing circuitry receives a coded bitstream carrying at least a picture, determines that a current coding unit (CU) in the picture is coded in a subblock based inter prediction mode based on a first syntax element value in the coded bitstream, and determines that one or more first subblocks in the current CU that is coded in the subblock based inter prediction mode are coded by intra prediction. The processing circuitry reconstructs one or more second subblocks of the current CU by inter prediction based on the subblock based inter prediction mode, the one or more second subblocks do not overlap with the one or more first subblocks in the current CU. The processing circuitry reconstructs the one or more first subblocks of the current CU by the intra prediction while the current CU is coded in the subblock based inter prediction mode.

Abstract: Aspects of the disclosure provide methods, apparatuses, and non-transitory computer-readable storage mediums for video encoding/decoding. An apparatus includes processing circuitry that partitions a current block of a current picture based on a geometric partitioning mode (GPM). The current block is partitioned into two partitions in the GPM mode. Each of the partitions is associated with a respective predictor. A weighting index for a sample of the current block is determined based on a position of the sample. A weighting factor is calculated based on the weighting index of the sample according to an equation that converts the weighting index to the weighting factor. The sample is encoded based on the weighting factor and the predictor corresponding to the sample.

Abstract: A coded video bitstream comprising a current block in a current picture is received. The current block includes a plurality of subblocks and is to be predicted by a subblock-based template matching motion vector prediction (SbTMVP) mode. A respective collocated reference subblock for each subblock is determined based on a combination of a displacement vector (DV) and a motion vector offset (MVO) that are associated with the respective subblock. A motion vector (MV) field in the respective collocated reference subblock of each subblock in the current block is determined. A respective reference template for each subblock is derived based on the determined MV field of the collocated reference subblock. The plurality of subblocks of the current block is reconstructed by predicting each subblock using the respective reference template in the SbTMVP mode.

Abstract: Coded information of a first color component and a second color component associated with a current block is determined. A first prediction mode is determined to be selected from an intra prediction mode, an inter prediction mode, or a combined intra-inter prediction mode for the first color component associated with the current block. A second prediction mode is determined to be selected from the intra prediction mode, the inter prediction mode, or the combined intra-inter prediction mode for the second color component associated with the current block. The second prediction mode is different from the first prediction mode. The current block is reconstructed based on predicting the first color component of the current block in the first prediction mode and predicting the second color component of the current block in the second prediction mode.

Abstract: In some examples, an apparatus for video decoding includes processing circuitry. The processing circuitry determines, from a candidate list, a first affine-translational merge candidate for a prediction of a current block in a current picture. The first affine-translational merge candidate provides affine motion information associated with a first reference picture in a first reference list and translational motion information associated with a second reference picture in a second reference list. The processing circuitry generates a first prediction for a sample in the current block according to the affine motion information associated with the first reference picture, and generates a second prediction for the sample in the current block according to the translational motion information associated with the second reference picture. The processing circuitry reconstructs the sample of the current block according to a combination of the first prediction and the second prediction.

Abstract: Processing circuitry receives, from a coded video bitstream, a first flag for a current block of an affine mode in a current picture, the first flag is associated with a first reference picture. The first flag indicates whether one or more motion vector differences of a reduced counting number are signaled. The reduced counting number is smaller than a number of first control points in a first affine model associated with the first reference picture. The processing circuitry decodes the one or more motion vector differences of the reduced counting number from the coded video bitstream in response to the first flag indicating the reduced counting number. The processing circuitry determines first control point motion vectors for the first control points in the first affine model according to the one or more motion vector differences of the reduced counting number, and reconstructs the current block accordingly.

Abstract: Aspects of the disclosure provide methods, apparatuses, and non-transitory computer-readable storage mediums for video encoding/decoding. In a method, whether an adaptive color transform (ACT) is enabled for a current block is determined. A maximum transform size is determined based on whether the ACT is enabled for the current block. Whether a subblock transform (SBT) is applied to the current block is determined based at least on the maximum transform size. Further, the SBT is performed on the current block based on the SBT being determined to be applied to the current block.

Abstract: Aspects of the disclosure provide a method and an apparatus including processing circuitry that receives a coded video bitstream comprising a current picture that includes a current block. The processing circuitry determines, based on a syntax element in the coded video bitstream, that the current block including a plurality of subblocks is coded in a subblock-based temporal motion vector prediction (SbTMVP) mode. The processing circuitry determines a plurality of displacement vector (DV) predictor (DVP) candidates and receives a base index indicating a DVP in the plurality of DVP candidates and a DV offset of the current block. The processing circuitry determines a DV based on the DVP and the DV offset. The DV indicates a block collocated with the current block in a collocated reference picture. The processing circuitry reconstructs a subblock in the plurality of subblocks based on motion information of a corresponding subblock in the collocated block.

Abstract: Aspects of the disclosure provide a method and an apparatus for video encoding/decoding. The apparatus includes processing circuitry for: receiving prediction information of a current coding block in a current picture from a coded video bitstream, the prediction information indicating that the current coding block is coded using a subblock-based temporal motion vector prediction (SbTMVP) mode; deriving multiple displacement vector (DV) candidates by applying multiple DV offset candidates to a fixed DV predictor of the current coding block; comparing a template of the current coding block with each of multiple templates, each template of the multiple templates being located at a position specified by a corresponding one of the multiple DV candidates; calculating a cost value associated with each one of the multiple DV offset candidates based on the comparing; and reordering DV offset indices of the multiple DV offset candidates based on their calculated cost values.

Abstract: A decoding device is provided for decoding of a bitstream, and more specifically for predicting a picture area of an input image for decoding. The picture area has been divided into at least first and second parts by a partitioning boundary, and the pixels of each part are predicted according to suitable measures. Blending masks are then applied to generate blended regions for the predicted pixels, modifying the pixels to generate a complete prediction of the picture area based on both parts. The blending mask is based on first and second thresholds, which are defined relative to the partitioning boundary, and which may have different values to produce an asymmetrical blending relative to the boundary. Based on suitable threshold values, the prediction, combination, and decoding of the picture area is more adaptive to differing contents of the parts therein.

Abstract: In a method, a video bitstream comprising a current coding tree unit (CTU) in a current picture and a source CTU in a source picture is received. A value of a syntax element is determined. The syntax element indicates whether the current CTU is encoded using context-adaptive binary arithmetic coding (CABAC). Context parameters of a context model of the current CTU are derived based on (i) predefined context model initialization information, and (ii) CABAC state information of the source CTU corresponding to the current CTU. The CABAC state information is stored at a CTU level instead of a picture level or a slice level. The context model of the current CTU is determined based on the derived context parameters. The current CTU is reconstructed based on the determined context model.

Abstract: Aspects of the disclosure provide a method and an apparatus including processing circuitry that decodes a value of a syntax element that indicates whether a current block is coded with a geometric partition mode (GPM) along a partition edge intersecting the current block. If the value of the syntax element indicates that the current block is coded with the GPM and a condition for adaptive blending is satisfied, width candidates in a width candidate list are reordered using template matching (TM) that is based on a current template of the current block and reference templates that correspond to the respective width candidates. A width candidate is selected from the reordered width candidate list. A width of a blending area defined by boundaries on both sides of the partition edge is determined based on the selected width candidate. The blending area is determined based on the width of the blending area.

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 including processing circuitry that adds merge candidates into a merge candidate list of a current block in a current picture. The merge candidates include available merge candidates including one or more of spatial motion vector predictors (MVP(s)), temporal MVP(s), non-adjacent MVP(s), history-based MVP(s), and pairwise average MVP(s). Whether the merge candidate list includes all available SMVP, TMVP, NA-MVP, HMVP, and PAMVP, and no merge candidate in the merge candidate list has a zero motion vector (zero MV) are determined. If the merge candidate list includes all available SMVP, TMVP, NA-MVP, HMVP, and PAMVP, and no merge candidate in the merge candidate list has the zero MV, the merge candidate having the zero MV is added to the merge candidate list. Merge candidates in the merge candidate list including the merge candidate having the zero MV are reordered using template matching.

Abstract: Processing circuitry decodes, from a bitstream carrying a video including a current picture, a signal indicative of a subblock based intra block copy (IBC) merge mode for predicting a current block in the current picture. The processing circuitry determines a predictor offset (also referred to as offset BV) associated with the current block. The predictor offset indicates a predictor block in the current picture corresponding to the current block, the predictor block includes a plurality of predictor subblocks respectively corresponding to a plurality of subblocks in the current block. The processing circuitry determines a first block vector of a first subblock according to a first predictor block vector associated with a first predictor subblock. The processing circuitry reconstructs the first subblock in the current block according to the first block vector that points to a reference block for the first subblock in the current picture.

Abstract: Aspects of the disclosure provide methods, apparatuses, and non-transitory computer-readable storage mediums for video encoding/decoding. An apparatus includes processing circuitry that partitions a current block of a current picture based on a geometric partitioning mode (GPM). The current block is partitioned into two partitions in the GPM mode. Each of the partitions is associated with a respective predictor. A weighting index for a sample of the current block is determined based on a position of the sample. A weighting factor is calculated based on the weighting index of the sample according to an equation that converts the weighting index to the weighting factor. The sample is encoded based on the weighting factor and the predictor corresponding to the sample.

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 in a current picture is coded in a subblock-based frame-rate up conversion (FRUC) mode and determines a corresponding block of the current block based on an offset vector indicating an offset between the current block and the corresponding block in the current picture. The processing circuitry determines a temporal motion vector predictor (TMVP) of a first subblock in the corresponding block based on a subblock in a forward reference picture and a subblock in a backward reference picture. The subblocks in the forward and backward reference pictures are matched using the subblock-based FRUC mode. The processing circuitry determines a TMVP of a subblock in the current block based on the TMVP of the first subblock in the corresponding block.

Abstract: Whether one of (i) a boundary of a first reference subblock of a first subblock in a first reference picture is positioned beyond a boundary of the first reference picture and (ii) a boundary of a second reference subblock of the first subblock in a second reference picture is positioned beyond a boundary of the second reference picture is determined. Responsive to (i) the boundary of the first reference subblock of the first subblock in the first reference picture being beyond the boundary of the first reference picture and (ii) the boundary of the second reference subblock of the first subblock in the second reference picture being positioned within the boundary of the second reference picture, the first subblock of a current block is reconstructed based on a uni-prediction mode such that the first subblock is reconstructed based on the second reference subblock of the second reference picture.

Abstract: Aspects of the disclosure provide a method and an apparatus for video decoding. The apparatus includes processing circuitry that decodes prediction information of one or more blocks including a current block from a coded video bitstream. The prediction information indicates that local illumination compensation (LIC) is applied to the one or more blocks and includes LIC information of the one or more blocks. The processing circuitry determines a final scaling factor ?f1 and a final offset ?f1 of a first subblock in the current block based on the LIC information. The processing circuitry determines an updated first predictor subblock in a predictor corresponding to the current block based on the final scaling factor ?f1, the final offset ?f1, and the first predictor subblock. An updated value of a first sample in the first predictor subblock is equal to ?f1×pi1+?f1·pi1 is a value of the first sample.

Abstract: Aspects of the disclosure provide a method and an apparatus for video decoding. The apparatus includes processing circuitry that determines motion information of a current block. The motion information indicates one or more reference blocks of the current block. If a motion information constraint indicates that the one or more reference blocks are within picture boundaries of respective one or more reference pictures, the processing circuitry reconstructs the current block based on the one or more reference blocks. If a first motion vector (MV) points from a region in the current block to a first reference region of a first reference block that is outside a picture boundary of a first reference picture, the processing circuitry determines a first clipped MV pointing from the region to an updated first reference region by clipping the first MV where the updated first reference region is within the picture boundary.