IMAGE ENCODING/DECODING METHOD AND DEVICE, AND RECORDING MEDIUM STORING BITSTREAM
The present invention relates to a video decoding method, the video decoding method according to an embodiment of the present invention comprises, obtaining sub-picture information of a current sub-picture through at least one signaling level and decoding the current sub-picture using the sub-picture information, wherein the sub-picture information is obtained for each decoded sub-picture.
1 . An image decoding method comprising:
obtaining sub-picture information from a sequence parameter set (SPS) of a bitstream; and
decoding a current sub-picture based on the sub-picture information,
wherein the sub-picture information includes at least one of a first flag or a second flag,
wherein the first flag indicating whether a sub-picture ID is explicitly signaled,
wherein the second flag indicating whether the sub-picture ID is signaled in the SPS or a picture parameter set (PPS),
wherein, in response to the first flag indicating that the sub-picture ID is not explicitly signaled, the sub-picture ID is not explicitly signaled,
wherein, in response to the first flag indicating that the sub-picture ID is explicitly signaled, the second flag is obtained from the SPS,
wherein, in response to a value of the second flag being 1, the sub-picture ID is signaled from the SPS,
wherein, in response to the value of the second flag being 0, the sub-picture ID is signaled from the PPS, and
wherein the sub-picture information includes a third flag indicating whether sub-pictures included in a current picture have a same size.
2 . The image decoding method of claim 1 ,
wherein, in response to the third flag indicating that the sub-pictures included in the current picture do not have the same size, location information specifying a location of a top left coding tree unit (CTU) of the current sub-picture is signaled from the bitstream, and
wherein, in response to the third flag indicating that the sub-pictures included in the current picture have the same size, the location information is not signaled.
3 . The image decoding method of claim 1 ,
wherein, in response to the third flag indicating that the sub-pictures included in the current picture do not have the same size, size information of the current sub-picture is signaled from the bitstream, and
wherein the size information of the current sub-picture includes width and height information of the current sub-picture.
4 . The image decoding method of claim 1 , wherein the sub-picture information includes information indicating whether decoding is performed by determining the current sub-picture as a picture.
5 . The image decoding method of claim 1 , wherein the sub-picture information includes sub-picture filtering information indicating whether to apply filtering to a boundary of the current sub-picture.
6 . An image encoding method comprising:
determining sub-picture information based on a current sub-picture; and
encoding the sub-picture information into a sequence parameter set (SPS) of a bitstream,
wherein the sub-picture information includes at least one of a first flag or a second flag,
wherein the first flag indicating whether a sub-picture ID is explicitly signaled,
wherein the second flag indicating whether the sub-picture ID is signaled in the SPS or a picture parameter set (PPS),
wherein, in response to the sub-picture ID being encoded into the SPS, the second flag with a value of 1 is encoded,
wherein, in response to the sub-picture ID being encoded into the PPS, the second flag with a value of 0 is encoded,
wherein, in response to the second flag being encoded, the first flag with a value of 1, indicating that the sub-picture ID is explicitly signaled, is encoded into the SPS,
wherein, in response to the second flag being not encoded, the first flag with a value of 0, indicating that the sub-picture ID is not explicitly signaled, is encoded into the SPS,
wherein the sub-picture information includes a third flag indicating whether sub-pictures included in a current picture have a same size, and
wherein the sequence parameter set includes maximum width information specifying a maximum width of the current picture.
7 . A non-transitory computer-readable medium storing a bitstream generated by an encoding method, the method comprising:
determining sub-picture information based on a current sub-picture; and
encoding the sub-picture information into a sequence parameter set (SPS) of the bitstream,
wherein the sub-picture information includes at least one of a first flag or a second flag,
wherein the first flag indicating whether a sub-picture ID is explicitly signaled,
wherein the second flag indicating whether the sub-picture ID is signaled in the SPS or a picture parameter set (PPS),
wherein, in response to the sub-picture ID being encoded into the SPS, the second flag with a value of 1 is encoded,
wherein, in response to the sub-picture ID being encoded into the PPS, the second flag with a value of 0 is encoded,
wherein, in response to the second flag being encoded, the first flag with a value of 1, indicating that the sub-picture ID is explicitly signaled, is encoded into the SPS,
wherein, in response to the second flag being not encoded, the first flag with a value of 0, indicating that the sub-picture ID is not explicitly signaled, is encoded into the SPS,
wherein the sub-picture information includes a third flag indicating whether sub-pictures included in a current picture have a same size, and
wherein the sequence parameter set includes maximum width information specifying a maximum width of the current picture.