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 non-conforming bitstream if the received bitstream includes syntax elements in a video parameter set (VPS) that duplicate content for hypothetical reference decoder (HRD) parameter information for different operation points signaled in the VPS;

determining, for each received bitstream of the plurality of received bitstreams of video data, that the received bitstream is a conforming bitstream if the received bitstream does not include any syntax elements in the VPS that duplicate the content for the HRD parameter information for different operation points 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 bitstream indicating first HRD parameter information; and

decoding, if present, second syntax elements in the VPS within the bitstream indicating second HRD parameter information that is different from the first HRD parameter information.

2. The method of claim 1 , wherein the bitstream determined to be conforming does not include syntax elements in the VPS that duplicate the second HRD parameter information.

3. The method of claim 1 , further comprising decoding one or more syntax elements within the bitstream determined to be conforming, the one or more decoded syntax elements indicating whether a simple operation point mode is in use for one or more of the different operation points.

4. The method of claim 3 , further comprising decoding, based on an indication that the simple operation point mode is used for a first operation point of the different operation points, only a target layer identifier of a set of layer identifiers for the first operation point of the different operation points, wherein the first operation point is identified by the target layer identifier and a temporal identifier that indicates a temporal sub-layer of the bitstream determined to be conforming.

5. The method of claim 3 , further comprising explicitly decoding, based on an indication that the simple operation point mode is not used for a first operation point of the different operation points, each layer identifier of a set of layer identifiers for the first operation point of the different operation points.

6. The method of claim 1 , wherein the first HRD parameter information defines HRD parameter information used to check conformance of a sub-bitstream of a first operation point of the different operation points.

7. The method of claim 1 , wherein the syntax elements indicating the first HRD parameter information comprise a hrd_parameters( ) syntax structure in the VPS within the bitstream determined to be conforming.

8. 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 bitstream determined to be conforming, wherein the bitstream determined to be conforming 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.

9. The method of claim 8 , wherein the syntax elements indicating one or more of profile space, tier, compatible profiles, and profile-related constraints for the temporal sub-layers are not included in a profile_tier_level( ) syntax structure in the VPS within the bitstream determined to be conforming.

10. 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 hypothetical reference decoder (HRD) parameter information for different operation points,

wherein the conforming bitstream does not include any syntax elements in the VPS that duplicate the content for the HRD parameter information for the different operation points, and

wherein encoding the bitstream comprises:

encoding first syntax elements within the conforming bitstream, the first syntax elements indicating first HRD parameter information; and

encoding second syntax elements in the VPS within the conforming bitstream, the second syntax elements indicating second HRD parameter information that is different from the first HRD parameter information.

11. The method of claim 10 , wherein the conforming bitstream does not include syntax elements in the VPS that duplicate the second HRD parameter information.

12. The method of claim 10 , further comprising:

encoding, within the conforming bitstream, one or more syntax elements that indicate whether a simple operation point mode is in use for one or more of the different operation points.

13. The method of claim 12 , further comprising, based on an indication that the simple operation point mode is used for a first operation point of the different operation points, encoding 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.

14. The method of claim 13 , further comprising, based on an indication that the simple operation point mode is not used for a first operation point of the different operation points, explicitly encoding each layer identifier of a set of layer identifiers for the first operation point.

15. The method of claim 10 , wherein the first HRD parameter information defines HRD parameter information used to check conformance of a sub-bitstream of a first operation point of the different operation points.

16. The method of claim 10 , wherein the second syntax elements indicating the first HRD parameter information comprise a hrd_parameters( ) syntax structure in the VPS within the conforming bitstream.

17. The method of claim 10 , further comprising encoding third syntax elements indicating one or more of profile space, tier, compatible profiles, and 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.

18. The method of claim 17 , wherein the third syntax elements indicating one or more of profile space, tier, compatible profiles, and 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.

19. A video coding device comprising:

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

a video coder configured to:

code a conforming bitstream, 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 hypothetical reference decoder (HRD) parameter information 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 HRD parameter information for the different operation points are determined to be conforming bitstreams, and

wherein to code the conforming bitstream, the video coder is configured to:

code first syntax elements in the VPS within a conforming bitstream, the first syntax elements indicating first HRD parameter information; and

code, if present, second syntax elements in the VPS within the conforming bitstream, the second syntax elements indicating second HRD parameter information that is different from the first HRD parameter information.

20. The video coding device of claim 19 , wherein the conforming bitstream does not include syntax elements in the VPS that duplicate the second HRD parameter information.

21. The video coding device of claim 19 , wherein the video coder is further configured to code one or more syntax elements within the conforming bitstream, the one or more coded syntax elements indicating whether a simple operation point mode is in use for one or more of the different operation points.

22. The video coding device of claim 21 , wherein the video coder is further configured to code, based on an indication that the simple operation point mode is used for a first operation point of the different operation points, only a target layer identifier of a set of layer identifiers for the first operation point of the different operation points, 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.

23. The video coding device of claim 21 , the video coder further configured to explicitly code, based on an indication that the simple operation point mode is not used for a first operation point of the different operation points, each layer identifier of a set of layer identifiers for the first operation point of the different operation points.

24. The video coding device of claim 19 , wherein the first HRD parameter information defines HRD parameter information used to check conformance of a sub-bitstream of a first operation point of the different operation points.

25. The video coding device of claim 19 , wherein the second syntax elements indicating the first HRD parameter information comprise a hrd_parameters( ) syntax structure in the VPS within the conforming bitstream.

26. The video coding device of claim 19 , the video coder further configured to code syntax elements indicating one or more of profile space, tier, compatible profiles, and 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.

27. The video coding device of claim 26 , wherein the third syntax elements indicating one or more of profile space, tier, compatible profiles, and 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 device of claim 19 , wherein the video coder comprises a video decoder configured to:

decode the first syntax elements in the VPS indicating the first HRD parameter information, and

decode, if present, the second syntax elements in the VPS indicating the second HRD parameter information that is different from the first HRD parameter information.

29. The video coding device of claim 19 , wherein the video coder comprises a video encoder configured to: encode the first syntax elements in the VPS indicating the first HRD parameter information, and

encode, if present, the second syntax elements in the VPS indicating the second HRD parameter information that is different from the first HRD parameter information.

30. A non-transitory computer-readable storage medium having stored thereon instructions that, when executed, cause a processor of a device for coding video data to:

code a conforming bitstream, 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 hypothetical reference decoder (HRD) parameter information 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 HRD parameter information for the different operation points are determined to be conforming bitstreams, and wherein the instructions that cause the processor to code the conforming bitstream include instructions that, when executed, cause the processor to:

code first syntax elements in the VPS within a conforming bitstream, the first syntax elements indicating first HRD parameter information; and

code, if present, second syntax elements in the VPS within the conforming bitstream, the second syntax elements indicating second HRD parameter information that is different from the first HRD parameter information.

31. The non-transitory computer-readable storage medium of claim 30 , wherein the conforming bitstream does not include syntax elements in the VPS that duplicate the second HRD parameter information.

32. A video coding device comprising:

means for coding a conforming bitstream, 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 hypothetical reference decoder (HRD) parameter information 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 HRD parameter information for the different operation points are determined to be conforming bitstreams, and wherein the means for coding the conforming bitstream includes:

means for coding first syntax elements in the VPS within a conforming bitstream, the first syntax elements indicating first HRD parameter information; and

means for coding, if present, second syntax elements in the VPS within the conforming bitstream, the second syntax elements indicating second HRD parameter information that is different from the first HRD parameter information.

33. The video coding device of claim 32 , wherein the conforming bitstream does not include syntax elements in the VPS that duplicate the second HRD parameter information.

34. The video coding device of claim 32 , wherein the first HRD parameter information defines HRD used to check conformance of a sub-bitstream of a first operation point of the different operation points.