| JCTVC-O0099 Time code from AVC pic_timing() SEI for HEVC [C. Fogg (Harmonic), M. Naccari, Marta Mrak (BBC)]
Reviewed Thu pm (YKW).
This proposal requests that the time code elements similar as in AVC picture timing SEI message be signalled in an SEI message in HEVC. A new SEI message is proposed that can accompany each coded picture in the an HEVC bitstream of Main, Main10, and future profiles. This proposal suggests the following changes of the AVC time code syntax for HEVC, including: (1) the iterations of the clock_timestamp_flag loop should be determined by DeltaToDivisor; (2) increase the drop count n_frame to 9 bits to accommodate 300 fps in HEVC Table A.4; and (3) time_offset_length is inserted to signal the bit length of time_offset.
There was DVB LS recommending the adoption of this proposal.
It was commented that DeltaToDivisor is only derivable in certain conditions, and thus it was suggested to better directly signal the number of loops. Two bits would be sufficient.
It was commented that the time_offset syntax element in AVC was coded as i(v), while it is proposed to be u(v). Suggest to define i(v) if we don’t have it now.
It was commented that the SMPTE time code 12M had been updated to support higher frame rate, and that time code was widely used in systems.
It was commented that if it might be beneficial to have the code similar as in AVC.
It was commented that it might be more preferable to extend the picture timing SEI message instead of defining a new SEI message, as the time code information is related to some information in the picture timing SEI message, if the picture timing SEI message is extensible. It was confirmed that there is a generic SEI message extension mechanism that makes SEI messages specified in HEVC version 1 all extensible.
It was discussed whether to change the syntax element name "n_frames" to "n_pictures", and it was agreed to keep it as n_frames.
Decision: Adopted with the following changes:
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Instead of using DeltaToDivisor for the loop, directly signal the number of loops using a two-bit syntax element coded as u(2).
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Code the time_offset syntax element as i(v), same as in AVC. Copy the definition of i(v) in AVC.
Other aspects, such as possible of using or aligning with SMPTE time code 12M, defining a new SEI message or extending the existing the existing picture timing SEI message, are for further study in an AHG.
JCTVC-O0177 MV-HEVC/SHVC HLS: On Layers Not Present SEI message [Jung Won Kang (ETRI), Jinho Lee, Hahyun Lee, Jin Soo Choi, Truong Cong Thang (UoA)]
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