Systems and methods for signaling picture information in a slice header in video coding
This disclosure relates to video coding and more particularly to techniques for signaling picture information in a slice header for coded video. According to an aspect of an invention, a first flag syntax element specifying whether a picture header is present in a slice header is parsed; a second flag syntax element, specifying a luma mapping is used for a current slice or a luma mapping with a chroma scalling is not used for a current slice, and a third flag syntax element, specifying whether a scaling information for the current slice is derived, are parsed based on the first flag syntax element.
1. A method of decoding video data, the method comprising:
decoding an enabled flag syntax element, wherein the enabled flag syntax element specifies whether a luma mapping with chroma scaling is enabled for all slices associated with a picture header syntax structure;
receiving a slice header;
decoding a first flag syntax element in the slice header, wherein the first flag syntax element specifies whether the picture header syntax structure is present in the slice header;
determining whether a condition is satisfied, the condition including: (i) the enabled flag syntax element has a value of 1, which indicates that the luma mapping with chroma scaling is enabled and (ii) the first flag syntax element has a value of 0, which indicates that the picture header syntax structure is not present in the slice header; and
decoding a second flag syntax element in the slice header only if the condition is satisfied, wherein the second flag syntax element specifies a luma mapping is used for a current slice or a luma mapping with chroma scaling is not used for the current slice.
2. A device for decoding video data, the device comprising:
a processor; and
a memory associated with the processor, wherein the processor is configured to:
decode an enabled flag syntax element, wherein the enabled flag syntax element specifies whether a luma mapping with chroma scaling is enabled for all slices associated with a picture header syntax structure;
receive a slice header;
decode a first flag syntax element in the slice header, wherein the first flag syntax element specifies whether the picture header syntax structure is present in the slice header;
determine whether a condition is satisfied, the condition including: (i) the enabled flag syntax element has a value of 1, which indicates that the luma mapping with chroma scaling is enabled and (ii) the first flag syntax element has a value of 0, which indicates that the picture header syntax structure is not present in the slice header; and
decode a second flag syntax element in the slice header only if the condition is satisfied, wherein the second flag syntax element specifies a luma mapping is used for a current slice or a luma mapping with chroma scaling is not used for the current slice.
3. A device for encoding image data, the device comprising:
a processor; and
a memory associated with the processor, wherein the processor is configured to:
encode an enabled flag syntax element, wherein the enabled flag syntax element specifies whether a luma mapping with chroma scaling is enabled for all slices associated with a picture header syntax structure;
encode a first flag syntax element, wherein the first flag syntax element specifies whether the picture header syntax structure is present in a slice header;
determine whether a condition is satisfied, the condition including: (i) the enabled flag syntax element has a value of 1, which indicates that the luma mapping with chroma scaling is enabled and (ii) the first flag syntax element has a value of 0s which indicates that the picture header syntax structure is not present in the slice header; and
encode a second flag syntax element in the slice header only if the condition is satisfied, wherein the second flag syntax element specifies a luma mapping is used for a current slice or a luma mapping with chroma scaling is not used for the current slice.
4. A method of encoding image data, the method comprising:
encoding a enabled flag syntax element, wherein the enabled flag syntax element specifies whether a luma mapping with chroma scaling is enabled for all slices associated with a picture header syntax structure;
encoding a first flag syntax element, wherein the first flag syntax element specifies whether the picture header syntax structure is present in a slice header;
determining whether a condition is satisfied, the condition including: (i) the enabled flag syntax element has a value of 1, which indicates that the luma mapping with chroma scaling is enabled and (ii) the first flag syntax element has a value of 0, which indicates that the picture header syntax structure is not present in the slice header; and
encoding a second flag syntax element in the slice header only if the condition is satisfied, wherein the second flag syntax element specifies a luma mapping is used for a current slice or a luma mapping with chroma scaling is not used for the current slice.