Progress draft-ietf-avt-mpeg4-simple-05.txt Jan van der Meer - - PowerPoint PPT Presentation

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

Original AUs Interleaved AUs De-interleaved AUs 1 2 3 4 5 TS(9) TS(10) D(9) 6 7 8 9 . . . Delay due to “late” AUs D(1)+D(2)+D(4)+D(5) Delay due to “early” AUs D(3)+D(4)+D(6)+D(7) 3 6 1 4 7 2 5 8 9 . . . 1 2 3 4 5 6 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