Abstract: Exemplary video processing methods and apparatuses for coding a current block. One implementation operates by receiving input video data associated with a current block in a current picture; determining one or more Motion Vectors (MVs) for generating an OBMC region; generating one or more converted MVs by changing said one or more MVs to one or more integer MVs or changing a MV component of said one or more MVs to an integer component; deriving the OBMC region by motion compensation using said one or more converted MVs; applying OBMC by blending an OBMC predictor in the OBMC region with an original predictor; and encoding or decoding the current block.

Abstract: Methods and apparatus for in-loop processing of reconstructed video are disclosed. According to one method, a virtual boundary is determined for to-be-processed pixels in the current picture, where the virtual boundary is aligned with block boundaries and at least one to-be-processed pixel on a first side of the virtual boundary requires one or more second pixels on a second side of the virtual boundary. According to the method, the in-loop processing is modified if a target to-be-processed pixel requires at least one second pixel from the second side of the virtual boundary and the modified in-loop processing eliminates the need for any second pixel on the second side of the virtual boundary. According to another method, the operations of block classification are changed when part of the required pixels in one 10×10 window used in classification are at the other side of virtual boundaries.

Abstract: A video processing method comprises receiving input data of a current block, checking if the current block satisfies one or more predefined criteria, setting the current block to be a root block if the current block satisfies the predefined criteria, one or more color components of one or more blocks in the current block are not checked with the predefined criteria if the current block is a root block, encoding or decoding the one or more color components of one or more blocks in the current block using neighboring reconstructed samples of the one or more color components of the current block as reference samples if the current block is a root block. Each block in the current block is encoded or decoded using neighboring reconstructed samples of each block in the current block as reference samples if the current block is not a root block.

Abstract: Method and apparatus for constrained de-blocking filter are disclosed. According to one method, if a CU is partitioned into multiple sub-CUs, the de-blocking process is also applied to the sub-block boundaries inside the current filtered-reconstructed block. According to another method, if first reference samples used for the de-blocking process of a first boundary are to be modified by the de-blocking process of a second boundary, the first reference samples are replaced by padding samples that are not to be modified by the de-blocking process of the second boundary. According to yet another method, the de-blocking process is applied to a reconstructed block corresponding to a current block to result in a current filtered-reconstructed block regardless whether a boundary of the current block corresponds to an 8×8 sample grid boundaries.

Abstract: According to a method for Adaptive Loop Filter (ALF) processing of reconstructed video, multiple indicators are signaled in slice at an encoder side or parsed at a decoder side, where the multiple indicators are Adaptive Parameter Set (APS) indices associated with temporal ALF filter sets for the ALF processing. A current indicator is determined from the multiple indicators, where the current indicator is used to select a current ALF filter set. Filtered-reconstructed pixels are derived for the current block by applying the current ALF filter to the current block. In another method, if the ALF processing applied at a target sample requires an outside sample on other side of a target virtual boundary from the target sample, the outside sample is replaced by a padded sample.

Abstract: A method and apparatus Inter prediction for video coding including IBC (Intra Block Copy) coding tool are disclosed. According to one method, a current permitted band inside the current picture for the current block is identified. A target IBC candidate is selected, where a target block vector of the target IBC candidate points from the current block to a target reference block in the current picture. An adjusted candidate list is generated by taking into account of the target IBC candidate and the current permitted band. The current motion information associated with the current block is encoded using the adjusted candidate list at the video encoder side or decoded using the adjusted candidate list at the video decoder side using the adjusted candidate list. In another method, a syntax for a target MVD (Motion Vector Difference) is decoded without sign information or with reduced sign information of the target MVD.

Abstract: A method and apparatus of Inter prediction for video coding using Multi-hypothesis (MH) are disclosed. If an MH mode is used for the current block: at least one MH candidate is derived using reduced reference data by adjusting at least one coding-control setting; an Inter candidate list is generated, where the Inter candidate list comprises said at least one MH candidate; and current motion information associated with the current block is encoded using the Inter candidate list at the video encoder side or the current motion information associated with the current block is decoded at the video decoder side using the Merge candidate list. The coding control setting may correspond to prediction direction setting, filter tap setting, block size of reference block to be fetched, reference picture setting or motion limitation setting.

Abstract: Video processing methods and apparatuses in a video encoding or decoding system for processing a video picture partitioned into blocks with one or more partition constraints. The video encoding or decoding system receives input data of a current block and checks whether a predefined splitting type is allowed to partition the current block according to first and second constraints. The first constraint restricts each sub-block partitioned from the current block to be completely contained in one pipeline unit, and the second constraint restricts each sub-block partitioned from the current block to contain one or more complete pipeline units. The pipeline units are non-overlapping units in the video picture designed for pipeline processing. The current block is not partitioned by the predefined splitting type if any sub-block partitioned by the predefined splitting type violates both the first and second constraints. The system encodes or decodes the current block.

Abstract: An intra prediction method comprises receiving input data of a current block in a current picture, deriving multiple Most Probable Modes (MPMs) to be included in a MPM list for the current block, setting remaining intra prediction modes as non-MPMs, and encoding or decoding the current block according to a current intra prediction mode selecting from the MPMs and non-MPMs. The first MPM in the MPM list is Planar mode for blocks coded or to be coded in intra prediction, and one or more other MPMs in the MPM list are derived according to a number of available angular mode of one or more neighboring blocks of the current block.

Abstract: A deblocking filtering method includes receiving reconstructed video data associated with a block boundary in a video coding system. The block boundary has N lines of samples crossing the block boundary from a P side to a Q side of the boundary. The method further includes determining whether to apply a first filter set to reduce block artifacts at the block boundary based on whether a first inter-side difference of a first line of the N lines of samples is greater than an inter-side difference threshold, determining a filter length of a filter in the first filter set based on a first side length of the P side, and a second side length of the Q side when it is determined to apply the first filter set, and applying at least one filter in the first filter set with the determined filter length on the block boundary.

Abstract: Method and apparatus of using Bi-directional optical flow (BIO) for a true bi-direction predicted block are disclosed. According to one method of the present invention, the gradients are limited to a predefined bit-depth in order to reduce the computational complexity. According to another method, the data range of gradient sum and/or the difference between L0 and L1 interpolated pixels are shifted by a predefined bit-depth. The pre-defined bit-depth can be implicitly determined or signalled in a bit stream at a sequence level, picture level or slice level. The pre-defined bit-depth can also be determined dependent on input bit-depth.

Abstract: A method and apparatus of video coding using history-based candidate derivation are disclosed. According to one method, a current block is inside a Shared Merge candidate list Region (SMR) or a history-based parallel processing region is received. The current block is encoded or decoded using a Merge candidate list. Only if the current block is one of first-coded N (N?0) blocks, one of last-coded N blocks, or one of selected N blocks, the history-based candidate list is updated after the current block is encoded or decoded. In one embodiment, Merge candidate list is pre-generated for the current block in the SMR and is separately generated for the current block in the history-based parallel processing region. In another method, if the current block is inside the SMR or the history-based parallel processing region, the current block is encoded or decoded using a history-based candidate list associated with the root CU.

Abstract: Video data processing methods and apparatuses receive input data associated with a current split node partitioned from a parent node by a splitting type, determine a depth of the current split node according to the splitting type, and compare the depth of the current split node with a maximum delta QP signaling depth. A video decoding system derives a delta QP from one or more syntax elements signaled in a TU associated with the current split node according to the comparing result, reconstructs a final QP for the current split node based on a reference QP and the delta QP, and decodes one or more TUs associated with the current split node using the final QP. The depth is counted in a way considering different splitting types and splitting partitions.

Abstract: A method and apparatus for video coding are disclosed. According to the present invention, a flag is determined, where the flag indicates whether a scaling matrix is enabled or not enabled for non-separable secondary transform (NSST) coded blocks. When the current block is one NSST coded block and the flag indicates that the scaling matrix is enabled for the NSST blocks, the scaling matrix is determined and applied to the current block. When the current block is one NSST coded block and the flag indicates that the scaling matrix is not enabled for the NSST coded blocks, the scaling matrix is skipped for the current block. According to another method, for a rectangular block, a target scaling matrix is generated directly from a square base scaling matrix in one step without up-sampling-and-down-sampling or down-sampling-and-up-sampling.

Abstract: A method of video coding using generalized bi-prediction (GBi) receives input data associated with a current block in a current picture, wherein the input data comprises information associated with a block size of the current block, determines a set of weighting factor pairs, wherein a size of the set of weighting factor pairs depends on the block size of the current block, and derives a set of advanced motion vector prediction (AMVP) candidate lists comprising MVP (motion vector prediction) candidates. The method further derives a set of final motion information based on the MVP candidates, determines that the set of final information comprises a bi-prediction predictor, generates a final predictor by combining two reference blocks associated with the final motion information using a target weighting factor pair selected from the set of weighting factor pairs, and encodes or decoding the current block using the final predictor.

Abstract: Video processing methods and apparatuses for processing video pictures referring to a high-level syntax set include receiving input data, determining a first syntax element indicating whether reference picture resampling is disabled or constrained, determining a second syntax element indicating whether subpicture partitioning is disabled or constrained, and encoding or decoding the video pictures. The first and second syntax elements are restricted to disable or constrain subpicture partitioning when reference picture resampling is enabled or disable or constrain reference picture resampling when subpicture partitioning is enabled. The first syntax element and the second syntax element are syntax elements signaled in the high level syntax set.

Abstract: Video processing methods comprise receiving input data of a current block in a current picture, constructing a candidate list for the current block by including one or more History-based Motion Vector Predictor (HMVP) candidates, selecting one candidate from the candidate list, locating a reference block according to motion information of the selected candidate, and encoding or decoding the current block by predicting the current block using the reference block. The one or more HMVP candidates are fetched from a normal HMVP table if the current block is to be processed by a normal inter prediction mode, and the one or more HMVP candidates are fetched form a Current Picture Referencing (CPR) HMVP table if the current block is to be processed by a CPR mode. The two HMVP tables are separately maintained and updated.

Abstract: A video processing method comprises receiving input data of a current block, checking if the current block satisfies one or more predefined criteria, setting the current block to be a root block if the current block satisfies the predefined criteria, one or more color components of one or more blocks in the current block are not checked with the predefined criteria if the current block is a root block, encoding or decoding the one or more color components of one or more blocks in the current block using neighboring reconstructed samples of the one or more color components of the current block as reference samples if the current block is a root block. Each block in the current block is encoded or decoded using neighboring reconstructed samples of each block in the current block as reference samples if the current block is not a root block.

Abstract: The techniques described herein relate to methods, apparatus, and computer readable media configured to encode or decode video data. A current block of video data is coded using affine prediction. A first set of candidates of a candidate list for the current block is generated, including determining one or more inherited candidates and deriving one or more constructed candidates. After generating the first set of candidates, it is determined whether the candidate list is full. Upon determining the candidate list is not full, the candidate list is filled by generating a second set of candidates of the candidate list, including one or more of generating one or more zero motion vector candidates, generating one or more additional derived candidates based on the plurality of associated neighboring blocks of the current block, and generating a temporal motion vector candidate based on a temporal collocated picture.

Abstract: A method and apparatus of Inter prediction for video coding using UMVE (Ultimate Motion Vector Expression) are disclosed. According to this method, a base candidate is selected from an original Inter candidate list, where the base candidate has a base prediction direction. One or more extended candidates are derived by adding one or more offsets to the base candidate, where said one or more extended candidates have a same prediction direction as the base prediction direction. The extended candidates are then inserted into the original Inter candidate list to form an extended Inter candidate list for encoding or decoding. According to another method, the UMVE mode is treated as an additional AMVP (Advanced Motion Vector Prediction) mode.