Image signal encoding/decoding method and device for same
An image decoding method according to the present invention may comprise: splitting a picture into a plurality of tiles; and determining at least one slice on the basis of the plurality of tiles. Here, splitting a picture into a plurality of tiles may comprise: determining the width of a first tile column in the picture; and determining the width of a second tile column neighboring the first tile column.
1. A method of decoding a video, the method comprising:
decoding slice determination method information indicating a slice determination method when a current picture is partitioned into a plurality of tiles, the slice determination method information indicating whether the slice determination method is a raster scanning order mode or a rectangular shape mode; and
determining at least one slice according to the slice determination method;
wherein when the slice determination method information indicates that the slice determination method is the rectangular shape mode, the method further comprises:
decoding slice number information specifying a number of slices included in the current picture; and
determining, based on whether a first slice is the last one among a plurality of slices in the current picture or not, whether to decode tile index differential information for the first slice,
wherein when the first slice is not the last one among the plurality of slices in the current picture, the tile index differential information for the first slice is decoded from a bitstream, the tile index differential information representing a difference between an index of a tile at a top-left position in the first slice and an index of a tile at a top-left position in a second slice, and
wherein when the first slice is the last one among the plurality of slices in the current picture, the tile index differential information for the first slice is not decoded from the bitstream.
2. The method of claim 1 , wherein the index of the tile at the top-left position in the second slice is derived by adding a value of the tile index differential information to the index of the tile at the top-left position in the first slice.
3. The method of claim 1 , wherein the method further comprises determining whether to decode size information for the first slice, and
wherein determination of whether to decode the size information for the first slice is based on whether the first slice is the last one among the plurality of slices or not.
4. The method of claim 1 , wherein when the slice determination method information indicates that the slice determination method is the raster scanning mode, a slice is determined based on number information indicating a number of tiles included in the slice.
5. A method of encoding a video, the method comprising:
encoding slice determination method information indicating a slice determination method, wherein the slice determination method information is encoded only when a current picture is partitioned into a plurality of tiles, and
wherein the slice determination method information indicates whether the slice determination method is a raster scanning order mode or a rectangular shape mode; and
determining at least one slice according to the slice determination method;
wherein in response to a determination that the slice determination method is the rectangular shape mode, the method further comprises:
encoding slice number information specifying a number of slices included in the current picture; and
determining, based on whether a first slice is the last one among a plurality of slices in the current picture or not, whether to encode tile index differential information for the first slice,
wherein when the first slice is not the last one among the plurality of slices in the current picture, the tile index differential information for the first slice is encoded in a bitstream, the tile index differential information representing a difference between an index of a tile at a top-left position in the first slice and an index of a tile at a top-left position in a second slice, and
wherein when the first slice is the last one among the plurality of slices in the current picture, encoding of the tile index differential information for the first slice is omitted.
6. The method of claim 5 , wherein a value of the tile index differential information is derived by subtracting the index of the tile at the top-left position in the first slice from the index of the tile at the top-left position in the second slice.
7. The method of claim 5 , wherein the method further comprises determining whether to encode size information for the first slice, and
wherein determination of whether to encode the size information for the first slice is based on whether the first slice is the last one among the plurality of slices or not.
8. The method of claim 5 , wherein when the slice determination method information indicates that the slice determination method is the raster scanning mode, a slice is determined based on number information indicating a number of tiles included in the slice.
9. A device for storing a compressed video data which being generated with program instructions, when the program instructions being executed, the device being configured to:
encode slice determination method information indicating a slice determination method,
wherein the slice determination method information is encoded only when a current picture is partitioned into a plurality of tiles, and
wherein the slice determination method information indicates whether the slice determination method is a raster scanning order mode or a rectangular shape mode; and
determine at least one slice according to the slice determination method,
wherein in response to a determination that the slice determination method is the rectangular shape mode, the device is further configured to:
encode slice number information specifying a number of slices included in the current picture; and
determine, based on whether a first slice is the last one among a plurality of slices in the current picture or not, whether to encode tile index differential information for the first slice,
wherein when the first slice is not the last one among the plurality of slices in the current picture, the tile index differential information for the first slice is encoded in a bitstream, the tile index differential information representing a difference between an index of a tile at a top-left position in the first slice and an index of a tile at a top-left position in a second slice, and
wherein when the first slice is the last one among the plurality of slices in the current picture, encoding of the tile index differential information for the first slice is omitted.