1 Hybrid Bit-Stream Models (September 25, 2008 Ghent) FINAL

2 Test conditions PVS length: SD/HD => 16 –Rebuffering is NOT allowed PVS length: QCIF/QVGA –Variable for rebuffering: 16(SRC)/upto24(PVS) –Fixed: 10 sec –Rebuffering is allowed Definition: Rebuffering is freezing longer than 0.5s without skipping Maximum delay/advance in PVS? (+/ sec): other conditions will be identical as in the multimedia project [TBD] Decision: the maximum time limit for freezing or rebuffering is 8 seconds forQCIF/QVGA.

3 Subjective Test ACR HR (tentatively) for both QVGA/VGA and SD/HD Graphical, continuous ACR version may be also used. Numbers will be used along with semantic terms unless P.910rev is approved. Proposal. (1) Vittorio: Some concerns about ACR-HR, new subjective testing method. => prefer DSCQS, DSIS, at least 10 steps (2) Silvio: Propose to use a scale from 1 to 5 with steps of 1/10, Propose to use MOS (or MOS_adj) as a target value Decision: 11 scale ACR-HR(P.910)=10, DSCQS=1

4 Model Inputs  Model A (P.NAMS): TS, RTP, UDP, IP headers & (optional) longer freezing Model B (P.NBAMS): TS, RTP, UDP, IP headers, ES information & (optional) longer freezing  Hybrid models (FR/RR/NR) : bit stream data (TS, RTP, UDP, IP headers, ES information) & PVS (SRC if required)

5 Proponents & Preferred input types TextBit-stream (trace dump with arrival time) Don’t know OPTICOM Yonsei NEC Tektronix Ghent Univ. Symmetricom NTT Lancaster Univ BT KDDI Psytechnics SQ (1) Hybrid models

6 Proponents & Preferred input types Bit-stream (trace dump with arrival time) Don’t know NTT Telchemy Tektronix Ericsson DT Ghent Univ Symmetricom BT KDDI Psytechnics NEC (2) P.NAMS: Use only IP, UDP, RTP and TS headers Note: Potential proponents should declare their intensions to SG12 by Sep. 30.

7 Proponents & Preferred input types TextBitstreamDon’t know Ericsson Ghent Univ DT Symmetricom NTT BT KDDI Psytechnics (3) P.NBAMS

8 ILGs CRC INTEL Acreo IRCCyN Nortel FUB NTIA

9 Reference Decoder [TBD] Reference decoder to ensure error-free bit stream compliance to the standard (open source) –Open-source H.264 codec (JM) Alternative: x264 –Open-source MPEG2 (FFMPEG) –Open-source MPEG4 - momusys, Xvid?? NOTE: Proponents should provide a working system of entire chains (encoder, container, server, capture program, decoder, etc)

10 Capturing bit stream data [TBD] File format: PCAP, RTP dump, MS Network Analyzer format (.cap). Capturing programs: Wireshark, Tcpdump, MS Network Analyzer format Protocol: TCP/IP, UDP??

11 Streaming Server [TBD] Representative streaming server –Live555: working for MPEG2 –VLC: working for H.264 and MPEG4 –Dvbstream: working for ??? –Helix: working for ??? –Ffserver: MPEG2 and MPEG4, H.264(?)

12 Inputs to the model Text file (Hybrid) Bit stream data (Bitstream/Hybrid)

13 Inputs to the model

14 Issues with Inputs to the model [TBD] If bit-stream data which contains transmission errors can ’ t be interpreted by some models, what will we do about the models?

15 IP analyzer: converter & decoder We need to convert the captured bit stream data so that the reference decoder can decode it. programs??? (TCP replay, off-line simulator) Free or open-source SW?? Hire professional developer??

16 IP analyzer Any bit stream data which can be understood by the reference IP analyzer will be admissible. Models are required to handle the bit stream data. Bottom Line: We need working programs for reference encoder, container, server, packet capturer, extractor and reference decoder so that the reference decoder can decode the captured bit stream data. Also the transmission error information should be outputted.

17 Data Analysis Same as the multimedia project – tentatively agreed.

18 Target usage (PLR): TBD SD/HD: (information from Broadband forum may be useful) QCIF/VGA - internet: - mobile: 0-15%

19 Drafting test plan A draft of the hybrid test plan will be done by the co-chairs (JB, CL) and editors (David Hands, Nicolas Staelens, Vittorio Baroncini, Yves Dhondt) by borrowing heavily from the multimedia and HD test plans. The draft will be presented to VQEG for approval.

20 Schedule Proposal for a working system (encoder, server, capturing program, decoder): next VQEG meeting (Jan, 2009) Finalization of test plan: VQEG meeting after the reference IP analyzer is available: VQEG meeting (July, 2009) Model submission: Six months after the test plan is finalized.

21 Remaining issues [TBD] Subjective test –Multimedia project approach: proven, but delays may happen (about 6 month delay after model submission). Easy to correct errors –HDTV project approach: Fast, but there can be impasse if serious PVS problems occur. Difficult to correct errors.

22 Number of subjective tests (Proponents) BT 1 Ericson1 DT 1 Ghent Univ. 1 KDDI 2 Lancaster Univ 1 NEC 1 NTT 1 Opticom 1 Psytechnics 1 Symmetricom 1 SQ 1 Tektronix Yonsei 3 Total: 16

23 Number of subjective tests (ILG) CRC 0 INTEL 0 Acreo 0 or possibly 1 IRCCyN 1 Nortel FUB 1 NTIA 1? NOTE: ATIS option may be considered.

24 Remaining issues [TBD] Calibration limit: currently same as HDTV & Multimedia (will be decided over the reflector)

25 Remaining issues [TBD] Bit-stream models –P.NAMS (audio/video, video only) –P.NBAMS (audio/video, video only) –P.NBAMS with some additional information from decoder such as freeze frames (audio/video, video only) audio/video(P.NAMS) vs. Hybrid (video only) Decision: Initially video only. If enough audio(with video) subjective data is available, models for audio and audio/video will be also validated.