Signaling of subpicture structures
View Patent ↗A method for signaling subpicture structures for coded video is provided. A video decoder receives data from a bitstream to be decoded as a sequence of video pictures. The video decoder receives from the bitstream subpicture specification for one or more subpictures in the sequence of video pictures. The subpicture specification identifies a position and a size for each subpicture by providing an index that identifies a coding tree unit (CTU) for the subpicture. The video decoder reconstructs each subpicture for the sequence of video pictures according to the subpicture specification.
1. A video decoding method, comprising:
receiving data from a bitstream to be decoded as a sequence of video pictures;
receiving, from the bitstream, subpicture specification for one or more subpictures in the sequence of video pictures, the subpicture specification identifying a position and a size for each subpicture of the one or more subpictures by providing an index that identifies a coding tree unit (CTU) for the respective subpicture; and
reconstructing each subpicture of the one or more subpictures for the sequence of video pictures according to the subpicture specification,
wherein a syntax element in a sequence parameter set (SPS) of the sequence of video pictures indicates that one or more subpictures are present in the sequence of video pictures, and
wherein a syntax element in a picture parameter set (PPS) of a video picture in the sequence of video pictures indicates that all slices of the video picture are rectangular.
2. The method of claim 1 , wherein different CTUs correspond to different subpicture grids that are assigned different indices.
3. The method of claim 2 , wherein boundaries of the subpicture grids are defined using boundaries of CTUs.
4. The method of claim 1 , wherein the CTU identified by the provided index is at a corner of the subpicture.
5. The method of claim 1 , wherein the index is provided by the SPS of the sequence of video pictures.
6. The method of claim 5 , wherein the syntax element in the SPS specifies a number of subpictures of the sequence of video pictures.
7. The method of claim 5 , wherein an identifier for the subpicture is signaled in the SPS.
8. The method of claim 1 , wherein an identifier for the subpicture is signaled in a slice header of a slice.
9. The method of claim 1 , wherein an identifier for the subpicture is signaled in the PPS of a video picture in the sequence of video pictures.
10. A video encoding method, comprising:
receiving data to be encoded as a sequence of video pictures in a bitstream;
signaling, in the bitstream, subpicture specification for one or more subpictures in the sequence of video pictures, the subpicture specification identifying a position and a size for each subpicture of the one or more subpictures by providing an index that identifies a coding tree unit (CTU) for the respective subpicture; and
encoding each subpicture of the one or more subpictures for the sequence of video pictures according to the subpicture specification,
wherein a syntax element in a sequence parameter set (SPS) of the sequence of video pictures indicates that one or more subpictures are present in the sequence of video pictures, and
wherein a syntax element in a picture parameter set (PPS) of a video picture in the sequence of video pictures indicates that all slices of the video picture are rectangular.
11. An electronic apparatus, comprising:
a video decoder circuit configured to perform operations comprising:
receiving data from a bitstream to be decoded as a sequence of video pictures;
receiving, from the bitstream, subpicture specification for one or more subpictures in the sequence of video pictures, the subpicture specification identifying a position and a size for each subpicture of the one or more subpictures by providing an index that identifies a coding tree unit (CTU) for the respective subpicture; and
reconstructing each subpicture of the one or more subpictures for the sequence of video pictures according to the subpicture specification,
wherein a syntax element in a sequence parameter set (SPS) of the sequence of video pictures indicates that one or more subpictures are present in the sequence of video pictures, and
wherein a syntax element in a picture parameter set (PPS) of a video picture in the sequence of video pictures indicates that all slices of the video picture are rectangular.