Tile and slice partitioning in video processing
The present disclosure provides a computer-implemented method for encoding or decoding video. The method includes encoding or decoding, in a plurality of picture parameter sets (PPS) associated with pictures of a coded layer video sequence (CLVS), corresponding first PPS flags indicating whether pictures are allowed to be partitioned into a plurality of tiles or slices. In a first PPS, a corresponding first PPS flag with a first value indicates a first picture of the CLVS is unpartitioned, and in a second PPS, another corresponding first PPS flag with a second value being different from the first value indicates that a second picture of the CLVS is allowed to be partitioned.
1 . A method for coding video, comprising:
determining whether a picture is partitioned into a plurality of tiles or slices; and
in response to a determination that the picture is allowed to be partitioned into the plurality of tiles or slices, coding, in a picture parameter set (PPS), a first flag associated with a slice mode being applied to the picture referring to the PPS, wherein:
the first flag is coded with a first value when a raster-scan slice mode is to be applied to partition the picture, and
the first flag is coded with a second value different from the first value when a rectangular slice mode is to be applied to partition the picture.
2 . The method of claim 1 , wherein in the raster-scan slice mode, the picture is partitioned into a plurality of raster-scan slices and any of the raster-scan slices comprises a sequence of one or more complete tiles in a tile raster scan of the picture.
3 . The method of claim 1 , wherein in the rectangular slice mode, the picture is partitioned into a plurality of rectangular slices, wherein one of the rectangular slices comprises one or more tiles covering a rectangular region of the picture, or one of the rectangular slices covers one or more consecutive rows of coding tree units of a tile.
4 . The method of claim 1 , further comprising:
coding a first picture parameter specifying a number of provided slice heights for slices in a corresponding tile minus one, the first picture parameter being equal to 0 if the corresponding tile contains a single slice.
5 . The method of claim 4 , wherein a value of the first picture parameter is in an inclusive range of 0 to a height of the corresponding tile minus two.
6 . The method of claim 1 , further comprising:
coding a second picture parameter specifying the number of provided slice heights for slices in a corresponding tile, the second picture parameter being equal to 0 if the corresponding tile contains a single slice.
7 . The method of claim 6 , further comprising:
coding a third picture parameter specifying a height of a corresponding rectangular slice in the corresponding tile minus one.
8 . The method of claim 7 , wherein an upper bound value of the third picture parameter is the height of the corresponding tile minus two.
9 . The method of claim 7 , wherein an upper bound value of the third picture parameter is the height of the corresponding tile minus a fourth picture parameter, wherein the fourth picture parameter indicates the number of provided slice heights for slices in the corresponding tile.
10 . The method of claim 7 , wherein an upper bound value of the third picture parameter is the height of the corresponding tile minus a fifth picture parameter and further minus one,
wherein the fifth picture parameter indicates the number of provided slice heights for slices in the corresponding tile minus one.
11 . The method of claim 7 , wherein an upper bound value of the third picture parameter is a smaller one of the height of the corresponding tile minus two or the height of the corresponding tile minus the number of provided slice heights in the corresponding tile.
12 . The method of claim 1 , further comprising:
in response to the determination that the picture is allowed to be partitioned into the plurality of tiles or slices, coding, in the picture parameter set (PPS), a first syntax element for specifying the number of tile column widths that are provided.
13 . The method of claim 1 , further comprising:
in response to the determination that the picture is allowed to be partitioned into the plurality of tiles or slices, coding, in the picture parameter set (PPS), a second syntax element for specifying the number of tile row heights that are provided.
14 . The method of claim 1 , wherein coding the first flag comprises encoding the first flag.
15 . The method of claim 1 , wherein coding the first flag comprises decoding the first flag.
16 . A method for decoding a bitstream, the method comprising:
receiving a bitstream; and
decoding the bitstream to generate a video sequence, the decoding comprising:
determining whether a picture is partitioned into a plurality of tiles or slices
in response to a determination that the picture is allowed to be partitioned into the plurality of tiles or slices:
decoding, in a picture parameter set (PPS), a first flag associated with a slice mode being applied to the picture referring to the PPS, wherein the first flag is coded with a first value when a raster-scan slice mode is to be applied to partition the picture, and the first flag is coded with a second value different from the first value when a rectangular slice mode is to be applied to partition the picture.
17 . The method of claim 16 , wherein in the raster-scan slice mode, the picture is partitioned into a plurality of raster-scan slices and any of the raster-scan slices comprises a sequence of one or more complete tiles in a tile raster scan of the picture.
18 . The method of claim 16 , wherein in the rectangular slice mode, the picture is partitioned into a plurality of rectangular slices, wherein one of the rectangular slices comprises one or more tiles covering a rectangular region of the picture, or one of the rectangular slices covers one or more consecutive rows of coding tree units of a tile.
19 . The method of claim 16 , wherein the decoding further comprises:
decoding a first picture parameter specifying a number of provided slice heights for slices in a corresponding tile minus one, the first picture parameter being equal to 0 if the corresponding tile contains a single slice.
20 . A method of storing a bitstream of video data, wherein the bitstream comprises a picture parameter set (PPS) associated with at least one picture of a coded layer video sequence (CLVS), the method comprising:
generating a bitstream comprising coded information of a picture; and
storing the bitstream in a non-transitory computer readable medium,
wherein the bitstream is generated according to operations comprising:
determining whether the picture is partitioned into a plurality of tiles or slices; and
in response to a determination that the picture is allowed to be partitioned into the plurality of tiles or slices, coding, in the picture parameter set (PPS) of the bitstream, a first flag associated with a slice mode being applied to the picture referring to the PPS, wherein:
the first flag is coded with a first value when a raster-scan slice mode is to be applied to partition the picture, and the first flag is coded with a second value different from the first value when a rectangular slice mode is to be applied to partition the picture.