Abstract: A method, a computing device, and a computer readable storage medium are provided for video coding. The method may include deriving parameter ? and parameter ? for a CCLM mode by using a predetermined number of neighboring reconstructed luma samples and chroma samples in a CU; and generating a final chroma predictor for the chroma samples of the CU by using the parameter ? and the parameter ?.

Abstract: Methods and devices are provided for reducing the decoding latency introduced by LMCS. In one method, one or more luma prediction sample values are selected from an output of a bilinear filter of Decoder-side Motion Vector Derivation (DMVR), the one or more selected luma prediction sample values are adjusted into luma prediction sample values with the same bit depth as an original coding bit depth of an input video, the luma prediction sample values with the same bit depth as the original coding bit depth of the input video are used to derive a scaling factor for decoding one or more chroma residual samples, the scaling factor is used to scale one or more chroma residual samples, and one or more chroma residual samples are reconstructed by adding the one or more scaled chroma residual samples and their corresponding chroma prediction samples.

Abstract: An electronic apparatus performs a method of decoding video data. The method includes: receiving, from the video data, an Adaptation Parameter Set (APS) identifier associated with a number of previously used Cross-Component Sample Adaptive Offset (CCSAO) filter offset sets stored in APS; receiving, from the video data, a syntax in Picture Header (PH) or Slice Header (SH) that indicates the APS identifier used for a current picture or slice; decoding, for the current coding tree unit (CTU), a filter set index that indicates a particular previously used CCSAO filter offset set of the number of offset sets in the APS associated with the APS identifier; and applying the particular previously used CCSAO filter offset set to the current CTU of the video data.

Abstract: A method and a computing device are provided for video coding. The method may include deriving parameter ? and parameter ? for a CCLM mode by using a predetermined number of neighboring reconstructed luma samples and chroma samples in a CU; and generating a final chroma predictor for the chroma samples of the CU by using the parameter ? and the parameter ?.

Abstract: A bit-width representation method of prediction refinement with optical flow (PROF), apparatus, and a non-transitory computer-readable storage medium are provided. The method includes obtaining a reference picture I associated with a video block within the video signal, obtaining prediction samples I(i,j) of the video block from a reference block in the reference picture I, controlling internal bit-widths of a PROF derivation process for various representation precisions of internal PROF parameters by applying right-shifting to the internal PROF parameters based on different bit-shift values, obtaining prediction refinement values for samples in the video block based on the PROF derivation process being applied to the video block based on the prediction samples I(i,j), and obtaining prediction samples of the video block based on the combination of the prediction samples and the prediction refinement values.

Abstract: A method for decoding a video block in GPM includes: partitioning the video block into two geometric partitions; constructing a uni-directional motion victor (MV) candidate list by adding regular merge candidates; in response to determining that the candidate list is not full, constructing a first updated candidate list by adding additional uni-directional MVs derived from bi-prediction MVs of a regular merge candidate list to the candidate list; in response to determining that the first updated candidate list is not full, constructing a second updated candidate list by adding pairwise average candidates to the first updated candidate list; in response to determining that the second updated candidate list is not full, periodically adding zero uni-directional MVs to the second updated candidate list until a maximum length is reached; and respectively generating a uni-directional MV for each geometric partition.

Abstract: Implementations of the disclosure provide systems and methods for motion refinement in a video. The method may include determining an initial motion vector for a video block of a video frame from the video. The method may include determining a matching target based on a weighted combination of a first reference block from a first reference frame in the video and a second reference block from a second reference frame in the video. The method may include performing a bilateral matching based motion refinement process at a block level to iteratively update the initial motion vector based on the matching target until a refined motion vector is obtained. The method may include refining a motion vector for each sub-block in the video block using the refined motion vector of the video block. Refining the motion vector at a sub-block level applies an affine motion model of the video block.

Abstract: A computing device performs a method of decoding video data by reconstructing a luma block corresponding to a chroma block; searching a sub-group of a plurality of reconstructed neighboring luma samples in a predefined order to identify a maximum luma sample and a minimum luma sample; computing a down-sampled maximum luma sample corresponding to the maximum luma sample; computing a down-sampled minimum luma sample corresponding to the minimum luma sample; generating a linear model using the down-sampled maximum luma sample, the down-sampled minimum luma sample, the first reconstructed chroma sample, and the second reconstructed chroma sample; computing down-sampled luma samples from luma samples of the reconstructed luma block, wherein each down-sampled luma sample corresponds to a chroma sample of the chroma block; and predicting chroma samples of the chroma block by applying the liner model to the corresponding down-sampled luma samples.

Abstract: A method for video coding is provided. The method includes: deriving an initial motion vector (MV) of a current block; deriving a plurality of MV candidates for decoder-side motion vector refinement (DMVR); determining cost values for the initial MV and each of the MV candidates; obtaining updated cost values of both the initial MV and the MV candidates by adjusting at least one of the cost values to favor the initial MV; and deriving a refined MV based on the updated cost values of both the initial MV and the MV candidate.

Abstract: The present disclosure relates to an intra sub-partition (ISP) method of decoding a video signal.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for decoding a video signal. The method includes obtaining a first reference picture I associated with a video block, obtaining control point motion vectors (CPMVs) of an affine coding block based on the video block, obtaining prediction samples I(i, j) of the affine coding block, deriving PROF prediction sample refinements of the affine coding block based on the PROF, receiving an LIC flag that indicates whether the LIC is applied to the affine coding block, deriving, and when the LIC is applied, LIC weight and offset based on neighboring reconstructed samples of the affine coding block and their corresponding reference samples in the first reference picture, and obtaining final prediction samples of the affine coding block based on the PROF prediction sample refinements and the LIC weight and offset.

Abstract: A method for video coding is provided. The method includes: deriving an initial motion vector (MV) of a current block; deriving, by a decoder, an initial motion vector (MV) of a current block; determining, by the decoder, cost values for the initial MV and each of a plurality of MV candidates; obtaining, by the decoder, updated cost values by decreasing a cost value for the initial MV or increasing cost values for the MV candidates; and deriving, by the decoder, a refined MV based on the updated cost values.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for video decoding. In one method, a decoder receives a Sequence Parameter Set (SPS) rice extension flag that indicates whether an extension of rice parameter derivation for binarization of abs_remainder and dec_abs_level is enabled. In a second method, the decoder may receive a Sequence Parameter Set (SPS) rice adaption enabled flag that indicates whether rice parameter derivation for binarization of abs_remainder and dec_abs_level is used.

Abstract: An electronic apparatus performs a method of updating an inter-predicted current block using a neighboring affine block. The electronic apparatus first identifies a pixel within the inter-predicted current block, the pixel having a first inter-predicted pixel value. Next, the electronic apparatus determines a motion vector difference for the pixel based on a set of affine parameters of the neighboring affine block and then a pixel value difference for the pixel according to the motion vector difference. The pixel value difference is an inner product of the pixel value gradient vector and the motion vector difference as the pixel value difference. Finally, the electronic apparatus updates the first inter-predicted pixel value with the pixel value difference as a second inter-predicted pixel value.

Abstract: Methods and devices are provided for decoding a video block in GPM. The method includes: partitioning the video block into a first geometric partition and a second geometric partition; receiving a first template matching (TM) enable flag for the first geometric partition a second TM enable flag for the second geometric partition, the first TM enable flag indicating whether a uni-directional motion of the first geometric partition is refined by TM, and the second TM enable flag indicating whether a uni-directional motion of the second partition is refined by the TM; receiving a first merge GPM index for the first geometric partition and a second merge GPM index for the second geometric partition; constructing a uni-directional motion victor (MV) candidate list of the GPM; and generating a first uni-directional MV for the first geometric partition and a second uni-directional MV for the second geometric partition.

Abstract: Methods and devices are provided for deriving constructed affine merge candidates. The method includes obtaining a first reference picture and a second reference picture associated with an inter mode coded block, where the first reference picture is before a current picture and the second reference picture is after the current picture in display order, obtaining a first motion vector from the inter mode coded block to a reference block in the first reference picture, obtaining a second motion vector from the inter mode coded block to a reference block in the second reference picture, applying bi-directional optical flow (BDOF) or decoder-side motion vector refinement (DMVR) to the inter mode coded block based on a mode information of the inter mode coded block, and predicting a bi-prediction of the inter mode coded block based on the applied BDOF or DMVR.

Abstract: A method of subblock-based temporal motion vector prediction is performed at a computing device. The computing device acquires a video bitstream including data associated with multiple encoded pictures. While decoding a current picture in the video bitstream, the computing device selects, according to syntax elements signaled in the video bitstream, one reference picture as a collocated picture of the current picture, and determines a temporal vector between the collocated picture and the current picture from motion information of spatially neighboring blocks of a current code unit (CU) according to a fixed order. Next, the computing device splits the current CU into multiple sub-CUs, obtains a temporal motion vector predictor for each sub-CU from the temporal vector and motion information of a block in the collocated picture that corresponds to a respective subblock of the current picture and decodes the current CU according to the temporal motion vector predictors.

Abstract: A method of video coding comprises independently generating a respective intra prediction for each of a plurality of corresponding sub-partitions. Each respective intra prediction is generated using a plurality of reference samples from a current coding block. Illustratively, no reconstructed sample from a first sub-partition of the plurality of corresponding sub-partitions is used to generate a respective intra prediction for any other sub-partition of the plurality of corresponding sub-partitions, and each of the plurality of corresponding sub-partitions has a width less than or equal to 2.

Abstract: A method for video coding is provided, including: providing a motion vector (MV) rounding process that is configured to perform a MV rounding operation; applying the MV rounding process to at least a first MV used in a first prediction tool selected from a first set of tools including: pair-wise merge candidate, triangle prediction mode, and affine mode; and applying the MV rounding process to at least a second MV used in a second prediction tool selected from a second set of tools including: temporal motion vector prediction (TMVP), alternative temporal motion vector prediction (ATMVP), and merge mode with motion vector differences (MMVD).

Abstract: A method and a computing device are provided for video coding. The method may include deriving parameter ? and parameter ? for a CCLM mode by using a predetermined number of neighboring reconstructed luma samples and chroma samples in a CU; and generating a final chroma predictor for the chroma samples of the CU by using the parameter ? and the parameter ?.