Video decoding apparatus and video coding apparatus
A mechanism is provided that implements video coding and decoding such that only a specific partial image region on a screen can be independently decoded. A video decoding apparatus ( 31 ) according to an aspect of the present invention configures, in intra prediction, inter prediction, loop filter processing, or the like, a partial image region in a picture, handles a region outside the partial image region in a similar manner to a region outside the picture, and does not apply such restriction to a non-partial image region other than the partial image region in the picture.
1. A non-transitory machine-readable medium of a device storing one or more machine-executable instructions for signaling gradual refresh for decoding a set of pictures, the one or more machine-executable instructions, when executed by at least one processing unit of the device, cause the device to:
identify a first picture in the set of pictures as being associated with a gradual refreshed picture;
store a network abstraction layer (NAL) unit type in a coded stream associated with the first picture, the NAL unit type identifying presence of the gradual refreshed picture; and
store, in the coded stream, an enable flag to identify use of gradual refresh for decoding at least a subset of pictures in the set of pictures.
2. The non-transitory machine-readable medium of claim 1 , wherein the enable flag is stored in a sequence parameter set (SPS) of the coded stream associated with the first picture.
3. The non-transitory machine-readable medium of claim 1 , wherein the one or more machine-executable instructions, when executed by the at least one processing unit, further cause the device to:
store, in the coded stream, a picture number from the gradual refresh picture to a picture that is entirely decoded correctly.
4. The non-transitory machine-readable medium of claim 1 , wherein the NAL unit type identifying the presence of the gradual refreshed picture is stored in a NAL unit of the coded stream.
5. The non-transitory machine-readable medium of claim 1 , wherein the coded stream includes an encoding of the set of pictures including the first picture.
6. The non-transitory machine-readable medium of claim 1 , wherein the subset of pictures comprises the first picture.
7. The non-transitory machine-readable medium of claim 1 , wherein the subset of pictures comprises one or more pictures after the first picture.
8. The non-transitory machine-readable medium of claim 1 , wherein:
the subset of pictures comprises one or more pictures after the first picture, and
the one or more machine-executable instructions, when executed by the at least one processing unit, further cause the device to store, in the coded stream, the one or more pictures after the first picture.
9. The non-transitory machine-readable medium of claim 8 , wherein the one or more pictures after the first picture specify pictures that need to be processed after the first picture in order to completely decode the gradual refreshed picture.
10. The non-transitory machine-readable medium of claim 9 , wherein a parameter decoder of a video decoder uses the NAL unit type to identify the presence of the gradual refreshed picture and uses the stored one or more pictures after the first picture to identify the the pictures that need to be processed after the first picture in order to completely decode the gradual refreshed picture.
11. The non-transitory machine-readable medium of claim 8 , wherein storing the one or more pictures after the first picture comprises storing the one or more pictures after the first picture in a NAL unit parameter set of the coded stream associated with the first picture.
12. The non-transitory machine-readable medium of claim 11 , wherein the NAL unit parameter set is a sequence parameter set (SPS) of the coded stream associated with the first picture.