Abstract: A method of palette management for palette coding in a video coding system receives input data associated with a current block in a high-level picture structure and initializes a palette predictor in the high-level picture structure before a corresponding palette of a first palette-coded block in the high-level picture structure is coded. If a palette mode is selected for the current block, the method applies the palette coding to the current block using a current palette and updates the palette predictor based on the current palette to generate an updated palette predictor for a next block coded in the palette mode.

Abstract: A video coder that uses a shared candidate list to encode or decode multiple blocks of pixels within a shared boundary is provided. The video coder identifies a shared boundary encompassing a plurality of blocks of pixels of a current picture in a video sequence. The video coder identifies one or more prediction candidates as a shared candidate list based on neighbors of a region defined by the shared boundary. The video coder codes one or more blocks of pixels encompassed by the shared boundary by using one or more prediction candidates selected from the shared candidate list.

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 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: Methods and apparatus of video processing for a video coding system using Neural Network (NN) are disclosed. According to this method, a shifted region is determined for the filter region to avoid unavailable reconstructed or filtered-reconstructed video data for the NN processing of the filter region, where boundaries of the shifted region comprises region boundaries derived by shifting target boundaries upward, leftward, or both upward and leftward, and wherein the target boundaries correspond to one or more top boundaries and one or more left boundaries of target processing region including the current block and one or more remaining un-processed blocks. According to another method, the areas outside boundaries of pictures, slices, tiles, or tile groups are padded. In yet another method, a flag is used to indicate whether the NN processing is allowed to cross a boundary between two slices, two tiles or two tile groups.

Abstract: Methods and apparatus for cross-colour loop-filter processing of reconstructed video are disclosed. According to one method, a sum of filter coefficients for each of one or more candidate cross-colour loop filters is constrained to be a fixed value. One or more syntax elements indicating a value related to a total number of candidate filters in a filter set are signalled or parsed in the APS (Adaptation Parameter Set).

Abstract: A method and apparatus of video coding incorporating Deep Neural Network are disclosed. A target signal is processed using DNN (Deep Neural Network), where the target signal provided to DNN input corresponds to the reconstructed residual, output from the prediction process, the reconstruction process, one or more filtering processes, or a combination of them. The output data from DNN output is provided for the encoding process or the decoding process. The DNN can be used to restore pixel values of the target signal or to predict a sign of one or more residual pixels between the target signal and an original signal. An absolute value of one or more residual pixels can be signalled in the video bitstream and used with the sign to reduce residual error of the target signal.

Abstract: Methods and apparatus of motion compensation using the bi-directional optical flow (BIO) techniques are disclosed. According to one method of the present invention, the BIO process is applied to encode or decode bi-directional current block in Merge mode only or in AMVP (advanced motion vector prediction) mode only. According to another method, the BIO process conditionally to encode or decode the current block depending on a jointly-coded flag if the current block is coded using a bi-prediction mode. According to yet another method, x-offset value vx and y-offset value vy for the current block are added to the current motion vector to form a final motion vector. The final motion vector is then used as a reference motion vector for following blocks. In still yet another method, the BIO process is applied to the chroma component.

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: 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: 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: A method and apparatus for palette coding of a block of video data using a candidate prediction mode list with syntax redundancy removed are disclosed. In one embodiment, whether a redundant prediction mode exists in the candidate prediction mode list for the current samples of the current block is determined based on the candidate prediction mode list and the previous prediction mode associated with the previous samples. If the redundant prediction mode exists in the candidate prediction mode list, the redundant prediction mode is removed from the candidate prediction mode list to generate a reduced candidate prediction mode list. In another embodiment, whether a redundant predictor exists in a candidate predictor list for a current sample of the current block is determined based on a condition related to one or more predictors for the current sample of the current block.

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: 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: 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 include receiving input data associated with a current picture composed of multiple Coding Tree Units (CTUs) for encoding or decoding, partitioning the current picture into one or more slices including raster scan slices or rectangular slices, and for each slice in the current picture, encoding or decoding each slice by always processing CTUs within each slice in a raster scan order. Each slice includes an integer number of complete CTUs in the current picture that are exclusively contained in a single Network Access Layer (NAL) unit. Tile partition and tile concept may be removed to reduce the coding complexity of video processing.