1 Hybrid Bit-Stream Models (September 2008 Ghent)

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 Issue: the maximum time limit for freezing or rebuffering is 8 seconds (QCIF/QVGA)? Minimum length of SRC present in PVS? (+/1 0.5 sec)?

3 Subjective Test ACR w/ HRR (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. Decision: Tentatively accepted Proposal. (1) Vittorio: Some concerns about ACR-HR, new subjective testing method. (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

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 BT KDDI Psytechnics SQ (1) Hybrid models

6 Proponents & Preferred input types Bit-stream (trace dump with arrival time) Don’t know Telchemy Tektronix NTIA Ericsson DT Ghent Univ Symmetricom BT KDDI NTT Psytechnics (2) P.NAMS: Use only IP, UDP, RTP and TS headers

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

9 Reference Decoder Reference decoder to ensure error-free bit stream compliance to the standard (open source) –Open-source H.264 codec (JM) – Agreed Alternative: x264 –Open-source MPEG2 (FFMPEG) - Agreed –Open-source MPEG4 - TBD momusys, Xvid??

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 ??? –Darwin: working for H.264 and MPEG4

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??? 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?

18 Schedule Reference decoder for each codec: TBD Reference IP analyzer: TBD Finalization of test plan: VQEG meeting after the reference IP analyzer is available Model submission: Six months after the test plan is finalized.