An example method of video processing includes performing a conversion between a video comprising one or more pictures and a bitstream representation of the video. The bitstream representation is required to conform to a format rule that specifies that each picture is coded as one or more slices. The format rule prohibits samples in a picture from not being covered by any of the one or more slices.

A method of decoding a coded video bitstream implemented by a video decoder is provided. The method includes the video decoder determining whether a value for a first flag is provided by an external input; setting a first flag equal to the value provided by the external input and a second flag equal to the value of the first flag to prevent a gradual decoding refresh (GDR) picture from being output when the value for the first flag is provided by the external input; decoding the GDR picture; and storing the GDR picture in a decoded picture buffer (DPB).

The present disclosure relates to a motion compensation method and module, a chip, an electronic device, and a storage medium, to improve the problem of haloes easily appearing on the edges of moving objects.

A method for point cloud encoding includes generating, for a three-dimensional (3D) point cloud, video frames and atlas frames that includes pixels representing information about the 3D point cloud, wherein atlas tiles represent partitions in the atlas frames and video tiles represent partitions in the video frames. The method also includes setting a value for a syntax element according to relationships between sizes of the video tiles and sizes of the atlas tiles. The method further includes encoding the video frames and the atlas frames to generate video sub-bitstreams and an atlas sub-bitstream, respectively. Additionally, the method includes generating a bitstream based on the atlas sub-bitstream, the video sub-bitstreams, and the syntax element and transmitting the bitstream.

A method for point cloud encoding includes generating, for a three-dimensional (3D) point cloud, video frames and atlas frames that includes pixels representing information about the 3D point cloud, wherein atlas tiles represent partitions in the atlas frames and video tiles represent partitions in the video frames. The method also includes setting a value for a syntax element according to relationships between sizes of the video tiles and sizes of the atlas tiles. The method further includes encoding the video frames and the atlas frames to generate video sub-bitstreams and an atlas sub-bitstream, respectively. Additionally, the method includes generating a bitstream based on the atlas sub-bitstream, the video sub-bitstreams, and the syntax element and transmitting the bitstream.

A method of coding video data, including coding a first block of video data using affine motion compensation prediction, updating a history-based motion vector prediction table using one or more motion vectors from one or more blocks that spatially neighbor the first block, determining a motion vector for a second block of video data using the history-based motion vector prediction table, and coding the second block of video data using the determined motion vector.

A method of coding video data, including coding a first block of video data using affine motion compensation prediction, updating a history-based motion vector prediction table using one or more motion vectors from one or more blocks that spatially neighbor the first block, determining a motion vector for a second block of video data using the history-based motion vector prediction table, and coding the second block of video data using the determined motion vector.

Motion Vector Management for Decoder Side Motion Vector Refinement is disclosed. A method of video processing including: determining, for a conversion between a first block of video and a bitstream representation of the first block of video, whether and/or how to apply decoder-side motion vector refinement (DMVR) based on a signaled information; and performing the conversion based on the determination.

The present disclosure provides a method of video coding implemented by a decoding device or an encoding device for optimum usage of a hardware reference memory buffer, wherein a group of reference coding tree units (CTUs) for Intra Block Copy (IBC) mode prediction of a current block of a current CTU is determined based on a size of the current CTU, and wherein the reference samples of the current block are obtained from the group of reference CTUs.

A method for decoding a 360-degree image includes: receiving a bitstream obtained by encoding a 360-degree image; generating a prediction image by making reference to syntax information obtained from the received bitstream; combining the generated prediction image with a residual image obtained by dequantizing and inverse-transforming the bitstream to obtain a decoded image; and reconstructing the decoded image into a 360-degree image according to a projection format. Generating the prediction image includes: obtaining, from motion information in the syntax information, a motion vector candidate group including a motion vector of a block adjacent to a current block to be decoded; deriving a prediction motion vector from the motion vector candidate group based on selection information extracted from the motion information; and determining a prediction block for the current block to be decoded, using a final motion vector derived by adding the prediction motion vector to a differential motion vector extracted from the motion information.