1. A method of decoding video data, the method comprising:', 'decoding a unique identifier for each decoding unit in an access unit, wherein an identifier for one decoding unit is different than an identifier for any other decoding unit in the access unit;', 'determining which network access layer (NAL) units are associated with which decoding units based on the unique identifier for each decoding unit in the access unit; and', 'decoding the NAL units of each of the decoding units in the access unit, based on the determination, to reconstruct at least one picture.

2. The method of claim 1,', 'wherein decoding the unique identifier comprises decoding a first unique identifier from a first decoding unit information supplemental enhancement information (SEI) message for a first decoding unit, and decoding a second unique identifier from a second decoding unit information SEI message for a second decoding unit, and', 'wherein determining comprises determining that a first SEI NAL unit that includes the first decoding unit information SEI message and all NAL units that follow the first SEI NAL unit up to a second SEI NAL unit that includes the second decoding unit information SEI message are associated with the first decoding unit.

3. The method of claim 1 ,', 'wherein decoding the unique identifier comprises decoding the unique identifier in a slice header of a slice NAL unit, and', 'wherein determining comprises determining which decoding unit the slice NAL unit is associated with based on the unique identifier in the slice header.

4. The method of claim 1, further comprising:', 'decoding a first decoding unit information supplemental enhancement information (SEI) message that indicates information for a removal time of a decoding unit; and', 'decoding a second decoding unit information SEI message that is located between two NAL units associated with the decoding unit, wherein the second decoding unit information SEI message is a copy of the first decoding unit information SEI message.

5. The method of claim 1, wherein decoding the unique identifier comprises: decoding a first identifier for a first decoding unit in the access unit; and decoding a second, different identifier for a second, different decoding unit in the access unit,', 'wherein, if a value of the first identifier is less than a value of the second identifier, the first decoding unit precedes the second decoding unit in decoding order.

6. The method of claim 1, further comprising:', 'decoding a supplemental enhancement information (SEI) message in the access unit; and', 'decoding a copy of the SEI message in the access unit.

7. A method for encoding video data, the method comprising:', 'determining a unique identifier for each decoding unit in an access unit, wherein an identifier for one decoding unit is different than an identifier for any other decoding unit in the access unit;', 'determining which network access layer (NAL) units are associated with which decoding units of the access unit; and', 'generating for output each unique identifier in corresponding decoding units to indicate which NAL units are associated with which decoding units of the access unit.

8. The method of claim 7, wherein generating for output comprises including a first unique identifier for a first decoding unit in a first decoding unit information', 'supplemental enhancement information (SEI) message, the method further comprising: outputting all NAL units that are associated with the first decoding unit after outputting first decoding unit SEI message;', 'including a second unique identifier for a second decoding unit in a second decoding unit information SEI message; and', 'after outputting of all NAL units that are associated with the first decoding unit, outputting the second decoding unit information SEI message that includes the second unique identifier for the second decoding unit.

9. The method of claim 7,', 'wherein generating for output comprises including each unique identifier in corresponding slice headers of slice NAL units that are associated with corresponding decoding units

10. The method of claim 7, further comprising:', 'outputting, as part of a decoding unit, a first decoding unit information supplemental enhancement information (SEI) message that indicates information for a removal time of the decoding unit; and', 'outputting, as part of the decoding unit, a second decoding unit information SEI message, wherein the second decoding unit information SEI message is a copy of the first decoding unit information SEI message

11. The method of claim 7, wherein determining the unique identifier comprises: determining a first identifier for a first decoding unit in the access unit; and determining a second, different identifier for a second, different decoding unit in the access unit,', 'wherein, if a value of the first identifier is less than a value of the second identifier, the first decoding unit precedes the second decoding unit in decoding order

12. The method of claim 7, further comprising:', 'including a supplemental enhancement information (SEI) message in the access unit; and', 'including a copy of the SEI message in the access unit

13. A device for decoding video data, the device comprising a video decoder configured to:', 'decode a unique identifier for each decoding unit in an access unit, wherein an identifier for one decoding unit is different than an identifier for any other decoding unit in the access unit;', 'determine which network access layer (NAL) units are associated with which decoding units based on the unique identifier for each decoding unit in the access unit; and', 'decode the NAL units of each of the decoding units in the access unit, based on the determination, to reconstruct at least one picture

14. The device of claim 13,', 'wherein, to decode the unique identifier, the video decoder is configured to decode a first unique identifier from a first decoding unit information supplemental enhancement information (SEI) message for a first decoding unit, and decode a second unique identifier from a second decoding unit information SEI message for a second decoding unit, and', 'wherein, to determine, the video decoder is configured to determine that a first SEI NAL unit that includes the first decoding unit information SEI message and all NAL units that follow the first SEI NAL unit up to a second SEI NAL unit that includes the second decoding unit information SEI message are associated with the first decoding unit

15. The device of claim 13,', 'wherein, to decode the unique identifier, the video decoder is configured to decode the unique identifier in a slice header of a slice NAL unit, and', 'wherein, to determine, the video decoder is configured to determine which decoding unit the slice NAL unit is associated with based on the unique identifier in the slice header

16. The device of claim 13, wherein the video decoder is configured to:', 'decode a first decoding unit information supplemental enhancement information (SEI) message that indicates information for a removal time of a decoding unit; and decode a second decoding unit information SEI message that is located between two NAL units associated with the decoding unit, wherein the second decoding unit information SEI message is a copy of the first decoding unit information SEI message

17. The device of claim 13, wherein, to decode the unique identifier, the video decoder is configured to:', 'decode a first identifier for a first decoding unit in the access unit; and decode a second, different identifier for a second, different decoding unit in the access unit,', 'wherein, if a value of the first identifier is less than a value of the second identifier, the first decoding unit precedes the second decoding unit in decoding order

18. The device of claim 13, wherein the video decoder is configured to:', 'decode a supplemental enhancement information (SEI) message in the access unit; and', 'decode a copy of the SEI message in the access unit

19. The device of claim 13, wherein the device comprises one of:', 'a microprocessor;', 'an integrated circuit; and', 'a wireless device that includes the video decoder.

20. A device for encoding video data, the device comprising a video encoder configured to:', 'determine a unique identifier for each decoding unit in an access unit, wherein an identifier for one decoding unit is different than an identifier for any other decoding unit in the access unit;', 'determine which network access layer (NAL) units are associated with which decoding units of the access unit; and', 'generate for output each unique identifier in corresponding decoding units to indicate which NAL units are associated with which decoding units of the access unit.

21. The device of claim 20,', 'wherein, to generate for output, the video encoder is configured to include a first unique identifier for a first decoding unit in a first decoding unit information', 'supplemental enhancement information (SEI) message, and', 'wherein the video encoder is configured to:', 'output all NAL units that are associated with the first decoding unit after outputting first decoding unit SEI message;', 'include a second unique identifier for a second decoding unit in a second decoding unit information SEI message; and', 'after outputting of all NAL units that are associated with the first decoding unit, output the second decoding unit information SEI message that includes the second unique identifier for the second decoding unit.

22. The device of claim 20,', 'wherein, to generate for output, the video encoder is configured to include each unique identifier in corresponding slice headers of slice NAL units that are associated with corresponding decoding units.

23. The device of claim 20, wherein the video encoder is configured to:', 'output, as part of a decoding unit, a first decoding unit information supplemental enhancement information (SEI) message that indicates information for a removal time of the decoding unit; and', 'output, as part of the decoding unit, a second decoding unit information SEI message, wherein the second decoding unit information SEI message is a copy of the first decoding unit information SEI message.

24. The device of claim 20, wherein, to determine the unique identifier, the video encoder is configured to:', 'determine a first identifier for a first decoding unit in the access unit; and determine a second, different identifier for a second, different decoding unit in the access unit,', 'wherein, if a value of the first identifier is less than a value of the second identifier, the first decoding unit precedes the second decoding unit in decoding order.

25. The device of claim 20, wherein the video encoder is configured to:', 'include a supplemental enhancement information (SEI) message in the access unit; and', 'include a copy of the SEI message in the access unit.

26. A computer-readable storage medium having instructions stored thereon that when executed cause one or more processors of a device for decoding video data to: decode a unique identifier for each decoding unit in an access unit, wherein an identifier for one decoding unit is different than an identifier for any other decoding unit in the access unit;', 'determine which network access layer (NAL) units are associated with which decoding units based on the unique identifier for each decoding unit in the access unit; and', 'decode the NAL units of each of the decoding units in the access unit, based on the determination, to reconstruct at least one picture.

27. The computer-readable storage medium of claim 26,', 'wherein the instructions that cause the one or more processors to decode the unique identifier comprise instructions that cause the one or more processors to decode a first unique identifier from a first decoding unit information supplemental', 'enhancement information (SEI) message for a first decoding unit, and decode a second unique identifier from a second decoding unit information SEI message for a second decoding unit, and', 'wherein the instructions that cause the one or more processors to determine comprise instructions that cause the one or more processors to determine that a first SEI NAL unit that includes the first decoding unit information SEI message and all NAL units that follow the first SEI NAL unit up to a second SEI NAL unit that includes the second decoding unit information SEI message are associated with the first decoding unit.

28. The computer-readable storage medium of claim 26, further comprising instructions that cause the one or more processors to:', 'decode a supplemental enhancement information (SEI) message in the access unit; and', 'decode a copy of the SEI message in the access unit.

29. A device for decoding video data, the device comprising:', 'means for decoding a unique identifier for each decoding unit in an access unit, wherein an identifier for one decoding unit is different than an identifier for any other decoding unit in the access unit;', 'means for determining which network access layer (NAL) units are associated with which decoding units based on the unique identifier for each decoding unit in the access unit; and', 'means for decoding the NAL units of each of the decoding units in the access unit, based on the determination, to reconstruct at least one picture.

30. The device of claim 29,', 'wherein the means for decoding the unique identifier comprises means for decoding a first unique identifier from a first decoding unit information supplemental enhancement information (SEI) message for a first decoding unit, and means for decoding a second unique identifier from a second decoding unit information SEI message for a second decoding unit, and', 'wherein the means for determining comprises means for determining that a first SEI NAL unit that includes the first decoding unit information SEI message and all NAL units that follow the first SEI NAL unit up to a second SEI NAL unit that includes the second decoding unit information SEI message are associated with the first decoding unit.

31. The device of claim 29, further comprising:', 'means for decoding a supplemental enhancement information (SEI) message in the access unit; and', 'means for decoding a copy of the SEI message in the access unit.']