An example method of video processing includes partitioning, for a conversion between a current video block of a picture of a video and a bitstream of the video, the picture into one or more slices according to a requirement of bitstream conformance. The requirement of bitstream conformance specifies that a union of the one or more slices covers the whole picture, and a first syntax element is included in the bitstream to indicate whether the one or more slices have a rectangular shape. The method also includes performing the conversion at least based on the partitioning.

A video signal decoding device comprises a processor, wherein: the processor decodes a sequence parameter set (SPS) raw byte sequence payload (RBSP) syntax included in a bitstream of a video signal, and decodes the bitstream on the basis of the decoding result of the SPS RBSP syntax; the SPS RBSP syntax includes a first syntax element related to the number of one or more sub-pictures configuring one picture, and a second syntax element indicating whether to process a boundary of the one or more sub-pictures as a boundary of the one picture on the basis of the first syntax element; and the second syntax element is parsed only when the number of the one or more sub-pictures is two or more.

Various concepts which further improve multi-viewilayer coding concepts, are described.

Various concepts which further improve multi-viewilayer coding concepts, are described.

A video signal decoding device comprises a processor, wherein: the processor decodes a sequence parameter set (SPS) raw byte sequence payload (RBSP) syntax included in a bitstream of a video signal, and decodes the bitstream on the basis of the decoding result of the SPS RBSP syntax; the SPS RBSP syntax includes a first syntax element related to the number of one or more sub-pictures configuring one picture, and a second syntax element indicating whether to process a boundary of the one or more sub-pictures as a boundary of the one picture on the basis of the first syntax element; and the second syntax element is parsed only when the number of the one or more sub-pictures is two or more.

An improved method for coding video is provided that includes Virtual Reality (VR) sequences that enables more efficient encoding by organizing the VR sequence as a single 2D block structure. In the method, reference picture and subpicture lists are created and extended to account for coding of the VR sequence. To further improve coding efficiency, reference indexing can be provided for the temporal and spatial difference between a current VR picture block and the reference pictures and subpictures for the VR sequence. Further, because the reference subpictures for the VR sequence may not have the proper orientation once the VR sequence subpictures are organized into the VR sequence, reorientation of the reference subpictures is made so that the reference subpicture orientations match the current VR subpicture orientations.

An improved method for coding video is provided that includes Virtual Reality (VR) sequences that enables more efficient encoding by organizing the VR sequence as a single 2D block structure. In the method, reference picture and subpicture lists are created and extended to account for coding of the VR sequence. To further improve coding efficiency, reference indexing can be provided for the temporal and spatial difference between a current VR picture block and the reference pictures and subpictures for the VR sequence. Further, because the reference subpictures for the VR sequence may not have the proper orientation once the VR sequence subpictures are organized into the VR sequence, reorientation of the reference subpictures is made so that the reference subpicture orientations match the current VR subpicture orientations.

The present invention is about an image encoding/decoding method and apparatus. According to present invention, a method of decoding an image, the method comprising, deriving an initial motion vector of a current block; deriving a refined motion vector by using the initial motion vector; and generating a prediction block of the current block by using the refined motion vector.

Disclosed herein are related to a device and a method of remotely rendering an image. In one approach, a device divides an image of an artificial reality space into a plurality of slices. In one approach, the device encodes a first slice of the plurality of slices. In one approach, the device encodes a portion of a second slice of the plurality of slices, while the device encodes a portion of the first slice. In one approach, the device transmits the encoded first slice of the plurality of slices to a head wearable display. In one approach, the device transmits the encoded second slice of the plurality of slices to the head wearable display, while the device transmits a portion of the encoded first slice to the head wearable display.

Disclosed is an image data encoding/decoding method and apparatus. A method for decoding a 360-degree image comprises the steps of: 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, so as to obtain a decoded image; and reconstructing the decoded image into a 360-degree image according to a projection format.