1 Hybrid Bit-Stream Models (January 24-26, 2009 San Jose)

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Hybrid Bit-Stream Models(January 24-26, 2009 San Jose)

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Issues to be determined

• Are we going to use numerical values attached to each category?

• Decision: TBD

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Issues to be determined• Are we going to mix 10s and 16-24s SRC/PVS?

• PVS length: QCIF/QVGA – Variable for rebuffering: 16(SRC)/upto24(PVS) – Fixed: 10 sec– Rebuffering is allowed

• Decision: Don’t mix 10s and 16-24s. • TBD: Further study on 16-24s SRC/PVS (e.g., single ev

aluation values for 24 sec, user response to various length of PVSs). May propose a special test for rebuffering, including coding and transmission error impairments.

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Issues to be determined

• Evaluators should be seated facing the center of the video display at the specified viewing distance. That means that subject's eyes should be positioned opposite to the video display's center (i.e. centered both vertically and horizontally)

• Decision: Will be copied from the HD test plan. One viewer for QCIF/QVGS. 24 viewers for each test after screening (similar to MM).

• Ref: Hoffman’s papers (IEEE)

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Issues to be determined

• Are we going to include audio?

• Decision: No audio.

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Issues to be determined

• Display Monitors– QVGA/QCIF: LCD– SD: professional CRT or LCD– HD: LCD or professional CRT

• Decision: – QVGA/QCIF: LCD– SD: professional CRT – HD: LCD or professional CRT– PDP was voted not to be used.

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Issues to be determined

• Are we going to use the same LCD panel if LCD display is used?

• List of admissible LCD monitors?

• Decision: Using the same LCD panel is not required.

– QCIF/QVGA: TCO 06 or later version– CRT: professional quality– LCD for HD: same as in the HDTV project

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Issues to be determined

• For the HD/SD testing, the video will use the full screen dimensions and no background panel or black border will be present.

• Decision: For the HD/SD testing, the video will use the full screen dimensions and no background panel or black border will be present.

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Issues to be determined

• How long will be the session length?• How many PVSs are there per session?

• Decision: For 10s PVS, the number of the total PVSs is about 168.

• For 15s PVS (SD/HD), the number of the total PVSs is about 130.

• New vote: 10s (5), 15s (5) => We will use 15s SRC/PVS for SD/HD.

• For 16-24s PVS, TBD

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Issues to be determined

• Randomization: maximum number of viewers per order?

• Decision: The max number of views for each order is 6 assuming 24 viewers for SD/HD. (full randomization is recommended if possible).

• For QCIF/QVGA, different ordering for each viewer as in the MM project.

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Issues to be determined

• Test design? Full matrix?

• Decision: TBD

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Issues to be determined

• SRC admissibility? (e.g., at least 4 in ACR scale or ILGs will decide?)

• Decision: “Good” or better. Final decision will be made by ILGs.

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Issues to be determined

• SRC length– Option #1: extra 2 seconds or 20 frames– Option #2 (see test plan)

• Decision: extra 2 seconds at the beginning and end for 10s and 15s SRC/PVS.

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Issues to be determined

• Cropping & Rescaling (help from Margaret?)

• Decision: Margaret will revise the table 2 (page 29).

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Issues to be determined

• Test materials– MM sources– RRNR sources– NTIA HD– NTIA SD– ITU SD (some of them)– SVT HD– Other materials (Elephant’s Dream, Big Buck Bunny)

• FYI

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Issues to be determined• Codec

– H.264– MPEG2 (SD & HD only)– MPEG4 (QCIF & QVGA only)

• HRC (bitrate, frame rate)– QVGA/VGA: same as MM– SD: same as RRNR– HD: same as HD

• Decision: – Codec: H.264 (HD, SD, QVGA), MPEG2 (SD)

• HRC (bitrate, frame rate) => agreed the following conditions.– QVGA/VGA: same as MM– SD: same as RRNR– HD: same as HD

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Issues to be determined • Max. length of freezing or skipping (10s PVS)?

– 40% of the total length?

• Decision: • maximum of freezing within 10s: 3s (mandatory 5s)• maximum of skipping within 10s: 3s (mandatory 5s)• max total loss (including beginning and end): 1s (mandatory 2s)• (max total loss=max loss at begin + max loss at end)• max total extra (including beginning and end): 1s (mandatory : the entire

PVS must be contained in the SRC).• Anything can happen in-between (freezing with/without skipping, skipping

as long they meet the aforementioned conditions).

SRC (10s)

PVS (10s)

max loss

PVS (10s)

max extra

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Issues to be determined • Max. length of freezing or skipping (15s PVS)?

– 40% of the total length?

• Decision: • maximum of freezing within 15s: 3s (mandatory 5s)• maximum of skipping within 15s: 3s (mandatory 5s)• max total loss (including beginning and end): 1s (mandatory 2s)• (max total loss=max loss at begin + max loss at end)• max total extra (including beginning and end): 1s (mandatory : the entire

PVS must be contained in the SRC).• Anything can happen in-between (freezing with/without skipping, skipping

as long they meet the aforementioned conditions

SRC (10s)

PVS (10s)

max loss

PVS (10s)

max extra

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Issues to be determined

• Are we going to use the 11 scale ACR (the same decision as the HD project)?

• Decision: TBD

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Issues to be determined

• Are we going to allow proponents to conduct subjective tests?

• Decision: Yes

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Issues to be determined• How about model entry (e.g., 1. per codec, per resolution)?• SD/HD (H.264, MPEG2):• QCIF/QVGA (H.264, MPEG4):

– => Different model entry for each codec– => Four models (each model also include FR, RR, NR).

• Decision: • Three codec-resolution combinations.

• H.264 (HD/SD): FR, RR, NR• H.264 (QVGA): FR, RR, NR• MPEG2 (SD): FR, RR, NR

• A different model is allowed for each codec-resolution. In other words, a proponent may submit model(s) for any one or all of the three types.

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Number of subjective tests (Jan. 2009)

BT 1Ericsson1DT 1Ghent Univ. 1KDDI 2Lancaster Univ 1LINK 0NEC 0NTT 2Opticom 1Psytechnics 0Symmetricom 1SQ 1TektronixYonsei 3 (QVGA, SD, HD60)

Total: 15 (QVGA, SD, HD50, HD60)

HD 60i 　

HD 30p 　

HD 50i 　

HD 25p 　

SD 525 　

SG 625 　

QVGA 　

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Number of subjective tests (ILG, Jan 2009)

• CRC 0• INTEL 1• Acreo 0 or possibly 1• IRCCyN 1• Nortel 0• FUB 1• NTIA 0• Verizon 1

• NOTE: ATIS option may be considered.• 4 or 5

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Issues to be determined• Currently, there codecs are considered (H.264, MPEG2, MPEG4).

– SD/HD: MPEG2, H.264– QCIF/QVGA: MPEG4, H.264

• Side Channels for RR – HD (56 kbps, 128 kbps, 256 kbps) <= HDTV project– SD (15 kbps, 80 kbps, 256 kbps) <= RRNR-TV– QCIF (1 kbps, 10 kbps) <= MM– CIF (10 kbps, 64 kbps) <= MM

• Side Channel [TBD]– SD/HD: 15 kbps, 56 kbps, 128 kbps, 256 kbps– QVGA/QCIF: 1kbps, 10 kbps, 64 kbps

• Took voting and decided option #1– Option #1 H.264 (SD/HD), MPEG2 (SD), H.264 (QVGA) => Ten votes– Option #2 H.264 (SD/HD), MPEG2 (SD), H.264 (QVGA), MPEG4 (QVGA) => T

hee votes

• Decision: Three codec-resolutions will be tested– H.264 (SD/HD)– MPEG2 (SD)– H.264 (QVGA)

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Decision from the last meeting

(Sep. 2008, Ghent)

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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? (+/- 0.25 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.

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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 ter

ms unless P.910rev is approved.• Proposal.• (1) Vittorio: Some concerns about ACR-HR, new subjecti

ve 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

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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)

headerextractor

bit-stream data(trace dump with arrival time) P.NAMS

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Proponents & Preferred input types

Text Bit-stream (trace dump with arrival time)

Don’t know

OPTICOM

Yonsei

NEC

Tektronix

Ghent Univ.

Symmetricom

NTTLancaster Univ

BT

KDDI

Psytechnics

SQ

(1) Hybrid models

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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.

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Proponents & Preferred input types

Text Bitstream Don’t know

Ericsson

Ghent Univ

DT

Symmetricom

NTT

BT

KDDI

Psytechnics

(3) P.NBAMS

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ILGs

• CRC

• INTEL

• Acreo

• IRCCyN

• Nortel

• FUB

• NTIA

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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)

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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??

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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(?)

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Inputs to the model

• Text file (Hybrid)

• Bit stream data (Bitstream/Hybrid)

network decoder

bit-streamcapture

DISPLAY

bit-stream data(trace dump with arrival time)

videocapture

PVS

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Inputs to the model

Hybrid modelsbit-stream data(trace dump with arrival time)

PVS

headerextractor

bit-stream data(trace dump with arrival time)

P.NBAMSbit-stream data(trace dump with arrival time)

P.NAMS

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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?

referencedecoder

bit-stream datawithout transmission errors

reference IPanalyzer &decoder

bit-stream datawith transmission errors

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IP analyzer: converter & decoder • We need to convert the captured bit stream data so that the ref

erence decoder can decode it.• programs??? (TCP replay, off-line simulator)• Free or open-source SW??• Hire professional developer??

refererenceencoder

bit stream data

player

channel

packetcapturer

container server

extracterrefererencedecoderPVS

network emulator

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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.

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Data Analysis

• Same as the multimedia project – tentatively agreed.

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Target usage (PLR): TBD

• SD/HD: (information from Broadband forum may be useful)

• QCIF/VGA - internet: - mobile: 0-15%

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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.

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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.

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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.

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Number of subjective tests (Proponents)

BT 1Ericson1DT 1Ghent Univ. 1KDDI 2Lancaster Univ 1NEC 1NTT 1Opticom 1Psytechnics 1Symmetricom 1SQ 1TektronixYonsei 3

Total: 16

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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.

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Remaining issues [TBD]

• Calibration limit: currently same as HDTV & Multimedia (will be decided over the reflector)

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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.