Signaling layer identifiers for operation points in video coding

1. A method of decoding video data, the method comprising:

determining, for each received bitstream of a plurality of received bitstreams of video data, that the received bitstream is a conforming bitstream if the received bitstream satisfies a set of conditions, the set of conditions including a condition that the received bitstream does not include any syntax elements in a video parameter set (VPS) that duplicate content for an operation point signaled in the VPS;

for at least one bitstream of the plurality of received bitstreams determined to be conforming:

decoding first syntax elements in the VPS within the at least one bitstream indicating a first operation point;

decoding, if present, second syntax elements in the VPS within the at least one bitstream indicating a second operation point that is different from the first operation point;

decoding one or more syntax elements that indicate whether a simple operation point mode is in use for either the first operation point or the second operation point; and

performing one of:

explicitly decoding, based on an indication that the simple operation point mode is used for the first operation point, only a target layer identifier of a first set of layer identifiers for the first operation point, wherein the first operation point is identified by the target layer identifier and a temporal identifier that indicates a temporal sub-layer of the at least one bitstream determined to be conforming; or

explicitly decoding, based on an indication that the simple operation point mode is not used for the first operation point, each layer identifier of the first set of layer identifiers for the first operation point.

2. The method of claim 1 , wherein the first syntax elements indicate the first set of layer identifiers, and wherein the second syntax elements indicate a second set of layer identifiers, the first set of layer identifiers being different from the second set of layer identifiers.

3. The method of claim 2 , wherein the first set of layer identifiers identifies one or more network abstraction layer (NAL) units that belong to the temporal sub-layer of the at least one bitstream determined to be conforming.

4. The method of claim 1 , wherein the at least one bitstream determined to be conforming does not include syntax elements in the VPS that duplicate information of the second operation point.

5. The method of claim 1 , wherein the first syntax elements indicating the first operation point comprise an operation_point( ) syntax structure in the VPS within the at least one bitstream determined to be conforming.

6. The method of claim 1 , further comprising decoding syntax elements indicating one or more of profile space, tier, compatible profiles, and profile-related constraints for an entire coded video sequence of the at least one bitstream of the plurality of received bitstreams determined to be conforming, wherein the at least one bitstream of the plurality of received bitstreams determined to be conforming does not include syntax elements indicating one or more of profile space, a tier, compatible profiles, or profile-related constraints for one or more temporal sub-layers of the coded video sequence that include the temporal sub-layer.

7. The method of claim 6 , wherein the syntax elements indicating the one or more of the profile space, the tier, compatible profiles, or profile-related constraints for the temporal sub-layers are not included in a profile_tier_level( ) syntax structure in the VPS within the at least one bitstream determined to be conforming.

8. A method of encoding video data, the method comprising:

encoding a bitstream of video data such that the bitstream is a conforming bitstream,

wherein non-conforming bitstreams include syntax elements in a video parameter set (VPS) that duplicate content for an operation point signaled in the VPS,

wherein the conforming bitstream does not include any syntax elements in the VPS that duplicate the content for the operation point signaled in the VPS, and

wherein encoding the conforming bitstream comprises:

encoding first syntax elements in the conforming bitstream, the first syntax elements indicating a first operation point;

encoding second syntax elements in the VPS within the conforming bitstream, the second syntax elements indicating a second operation point that is different from the first operation point;

encoding, within the conforming bitstream, one or more syntax elements that indicate whether a simple operation point mode is in use for either the first operation point or the second operation point; and

performing one of:

encoding, based on an indication that the simple operation point mode is used for a first operation point of the first and second operation points, only a target layer identifier of a set of layer identifiers for the first operation point, wherein the first operation point is identified by the target layer identifier and a temporal identifier that indicates a temporal sub-layer of the conforming bitstream; or

encoding, based on an indication that the simple operation point mode is not used for a first operation point of the first and second operation points, explicitly encoding each layer identifier of the set of layer identifiers for the first operation point.

9. The method of claim 8 , wherein the first syntax elements indicate a first set of layer identifiers, and wherein the second syntax elements indicate a second set of layer identifiers, the first set of layer identifiers being different from the second set of layer identifiers.

10. The method of claim 9 , wherein the first set of layer identifiers identifies one or more network abstraction layer (NAL) units that belong to the temporal sub-layer of the conforming bitstream.

11. The method of claim 8 , wherein encoding the conforming bitstream comprises encoding the conforming bitstream such that the conforming bitstream does not include syntax elements in the VPS that duplicate information of the second operation point.

12. The method of claim 8 , wherein the first syntax elements indicating the first operation point comprise an operation_point( ) syntax structure in the VPS within the conforming bitstream.

13. The method of claim 8 , further comprising encoding, within the conforming bitstream, third syntax elements indicating one or more of a profile space, a tier, compatible profiles, or profile-related constraints for an entire coded video sequence of the conforming bitstream, wherein the conforming bitstream does not include syntax elements indicating one or more of profile space, a tier, compatible profiles, or profile-related constraints for one or more temporal sub-layers of the coded video sequence that include the temporal sub-layer.

14. The method of claim 13 , wherein the third syntax elements indicating the one or more of the profile space, the tier, the compatible profiles, or the profile-related constraints for the one or more temporal sub-layers are not included in a profile_tier_level( ) syntax structure in the VPS within the conforming bitstream.

15. A video coding device comprising:

a memory configured to store video data of one or more bitstreams; and

one or more processors configured to:

code a conforming bitstream of the one or more bitstreams stored to the memory, wherein a determination of whether the bitstream is conforming is defined such that:

bitstreams that include syntax elements in a video parameter set (VPS) that duplicate content for an operation point signaled in the VPS are determined to be non-conforming bitstreams, and

bitstreams that do not include any syntax elements in the VPS that duplicate the content for the operation point signaled in the VPS are determined to be conforming bitstreams, and

wherein to code the conforming bitstream, the one or more processors are configured to:

code first syntax elements in the VPS within the conforming bitstream, first syntax elements indicating a first operation point;

code second syntax elements in the VPS within the conforming bitstream, the second syntax elements indicating a second operation point that is different from the first operation point;

code one or more syntax elements that indicate whether a simple operation point mode is in use for either the first operation point or the second operation point;

explicitly code, based on an indication that the simple operation point mode is used for the first operation point, only a target layer identifier of a first set of layer identifiers for the first operation point, wherein the first operation point is identified by the target layer identifier and a temporal identifier that indicates a temporal sub-layer of the conforming bitstream; and

explicitly code, based on an indication that the simple operation point mode is not used for the first operation point, each layer identifier of the first set of layer identifiers for the first operation point.

16. The video coding device of claim 15 , wherein the first syntax elements indicate the first set of layer identifiers, and wherein the second syntax elements indicate a second set of layer identifiers, the first set of layer identifiers being different from the second set of layer identifiers.

17. The video coding device of claim 16 , wherein the first set of layer identifiers identifies one or more network abstraction layer (NAL) units that belong to the temporal sub-layer of the conforming bitstream.

18. The video coding device of claim 15 , wherein the conforming bitstream does not include syntax elements in the VPS that duplicate information of the second operation point.

19. The video coding device of claim 15 , wherein the first syntax elements indicating the first operation point comprise an operation_point( ) in the VPS within the conforming bitstream.

20. The video coding device of claim 15 , wherein the one or more processors are further configured to code, within the conforming bitstream, third syntax elements indicating one or more of a profile space, a tier, compatible profiles, or profile-related constraints for an entire coded video sequence of the conforming bitstream, wherein the conforming bitstream does not include syntax elements indicating one or more of profile space, tier, compatible profiles, and profile-related constraints for one or more temporal sub-layers of the coded video sequence that include the temporal sub-layer.

21. The video coding device of claim 20 , wherein the third syntax elements indicating the one or more of the profile space, the tier, the compatible profiles, or the profile-related constraints for the one or more temporal sub-layers are not included in a profile_tier_level( ) syntax structure in the VPS within the conforming bitstream.

22. A video coding apparatus comprising:

means for storing video data of one or more bitstreams;

means for coding a conforming bitstream of the one or more bitstreams, wherein a determination of whether the bitstream is conforming is defined such that:

bitstreams that include syntax elements in a video parameter set (VPS) that duplicate content for different operation points are determined to be non-conforming bitstreams, and

bitstreams that do not include any syntax elements in the VPS that duplicate the content for the different operation points are determined to be conforming bitstreams, and

wherein the means for coding the conforming bitstream includes:

means for coding, in the VPS within a conforming bitstream, first syntax elements indicating a first operation point;

means for coding second syntax elements in the VPS within the conforming bitstream, the second syntax elements indicating a second operation point that is different from the first operation point; and

means for explicitly coding, based on an indication that the simple operation point mode is used for the first operation point, only a target layer identifier of a first set of layer identifiers for the first operation point, wherein the first operation point is identified by the target layer identifier and a temporal identifier that indicates a temporal sub-layer of the conforming bitstream; and

means for explicitly coding, based on an indication that the simple operation point mode is not used for the first operation point, each layer identifier of the set of layer identifiers for the first operation point.

23. The video coding apparatus of claim 22 , wherein the first syntax elements indicate the first set of layer identifiers, and wherein the second syntax elements indicate a second set of layer identifiers, the first set of layer identifiers being different from the second set of layer identifiers.

24. The video coding apparatus of claim 23 , wherein the first set of layer identifiers identifies one or more network abstraction layer (NAL) units that belong to the temporal sub-layer of the conforming bitstream.

25. The video coding apparatus of claim 22 , wherein the conforming bitstream does not include syntax elements in the VPS that duplicate information of the second operation point.

26. The video coding apparatus of claim 22 , further comprising means for coding, within the conforming bitstream, third syntax elements indicating one or more of a profile space, tier, compatible profiles, or profile-related constraints for an entire coded video sequence of the conforming bitstream, wherein the conforming bitstream does not include syntax elements indicating one or more of profile space, a tier, compatible profiles, or profile-related constraints for one or more temporal sub-layers of the coded video sequence that include the temporal sub-layer.

27. The video coding apparatus of claim 26 , wherein the third syntax elements indicating the one or more of the profile space, the tier, the compatible profiles, or the profile-related constraints for the temporal sub-layers are not included in a profile_tier_level( ) syntax structure in the VPS within the conforming bitstream.

28. The video coding apparatus of claim 27 , wherein the first syntax elements indicating the first operation point comprise an operation_point( ) in the VPS within the conforming bitstream.