Progress draft-ietf-avt-mpeg4-simple-05.txt Jan van der Meer Philips Electronics jan.vandermeer@philips.com
Last WG Call Progress (1) • Several comments received – all of editorial nature – most important ones: • replace MIME format parameter “Profile” by “InterleaveDelay” • allow / disallow RTP packets to go backwards in time when interleaving example: interleaving pattern 0,5; 2,7; 4,9; 1,6; 3,8 – discussed in ISMA and MPEG
Last WG Call Progress (2) • Resolution in MPEG and ISMA – time consuming due to meeting schedules – replace MIME format parameter “Profile” by “InterleaveDelay” – allow RTP packets to go backwards in time when interleaving – draft-ietf-avt-mpeg4-simple-05.txt is mpeg-4 generic • Implementation – slow …. • Editorial work, but what is “interleave delay”
InterleaveDelay Issues • Definition – minimum delay caused by interleaving • no delay “indication”, accurate definition instead • allows accurate allocation of memory resources for de-interleaving • particular of interest in case of “reliable” IP networks • How to determine interleave delay – compliant definition (check “stream” of AUs) • De-interleaving and Concealment Rules – not easy – receiver architecture independent
TS(9) TS(10) Original AUs D(9) 0 1 2 3 4 5 6 7 8 9 . . . Interleaved AUs 0 3 6 1 4 7 2 5 8 9 . . . 0 1 2 3 4 5 6 De-interleaved AUs Delay due to “late” AUs Delay due to “early” AUs D(1)+D(2)+D(4)+D(5) D(3)+D(4)+D(6)+D(7) Note: “late” and “early” are defined within the interleaved AUs Interleave delay
De-interleaving and Concealment • Emission rule : – An AU(i) may be released for emission from the de- interleave buffer either : • if TS(i) <= TS(max received) – interleave delay) or • if it is the next AU to decode • For examples see draft -05
Conclusion • Draft available now • Unfortunately not in time for Atlanta deadline • Will be uploaded soon • Review highly welcome
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