1、 I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n ITU-T G.1071 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (06/2015) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Multimedia Quality of Service and performance Generic and user-related aspects Opinion
2、model for network planning of video and audio streaming applications Recommendation ITU-T G.1071 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G.199 GENERAL CHARACTERISTICS COMMON TO ALL ANALOGUE CARR
3、IER-TRANSMISSION SYSTEMS G.200G.299 INDIVIDUAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINES G.300G.399 GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WITH METALLIC LINES G.400G.449 COORDINATION
4、OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.499 TRANSMISSION MEDIA AND OPTICAL SYSTEMS CHARACTERISTICS G.600G.699 DIGITAL TERMINAL EQUIPMENTS G.700G.799 DIGITAL NETWORKS G.800G.899 DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.900G.999 MULTIMEDIA QUALITY OF SERVICE AND PERFORMANCE GENERIC AND USER-RELA
5、TED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G.6000G.6999 DATA OVER TRANSPORT GENERIC ASPECTS G.7000G.7999 PACKET OVER TRANSPORT ASPECTS G.8000G.8999 ACCESS NETWORKS G.9000G.9999 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T G.1071 (06/2015) i Reco
6、mmendation ITU-T G.1071 Opinion model for network planning of video and audio streaming applications Summary Recommendation ITU-T G.1071 provides algorithmic models for network planning of IP-based video services. This Recommendation addresses two application areas: the higher resolution (HR) applic
7、ation area, including services such as IPTV; the lower resolution (LR) application area, including services such as mobile TV. The algorithmic model addressing the HR application area is described in Annex A. The algorithmic model addressing the LR application area is described in Annex B. The appli
8、cation of the models is limited to QoE/QoS planning. Other applications such as quality benchmarking and monitoring are outside the scope of this Recommendation. As input, the models take network planning assumptions, for example, the video resolution, the audio and video codec types and profiles, t
9、he audio and video bitrates, the packet-loss-rate and the packet-loss distribution. As output, the model algorithms provide individual estimates of audio, video and audiovisual quality in terms of the five-point absolute category rating (ACR) mean opinion score (MOS) scale. Further diagnostic inform
10、ation on causes of quality degradations can also be made available. History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T G.1071 2015-06-29 12 11.1002/1000/12512 Keywords Audio, audiovisual, IPTV, mean opinion score (MOS), mobile TV, network planning, quality, QoE, video. _ * To a
11、ccess the Recommendation, type the URL http:/handle.itu.int/ in the address field of your web browser, followed by the Recommendations unique ID. For example, http:/handle.itu.int/11.1002/1000/11830-en. ii Rec. ITU-T G.1071 (06/2015) FOREWORD The International Telecommunication Union (ITU) is the Un
12、ited Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recomme
13、ndations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The ap
14、proval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administr
15、ation“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compli
16、ance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is
17、 required of any party. INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Inte
18、llectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. Ho
19、wever, implementers are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2015 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the
20、prior written permission of ITU. Rec. ITU-T G.1071 (06/2015) iii Table of Contents Page 1 Scope . 1 2 References . 1 3 Definitions 2 3.1 Terms defined elsewhere 2 3.2 Terms defined in this Recommendation . 2 4 Abbreviations and acronyms 2 5 Conventions 3 6 Areas of application 4 7 Model framework .
21、7 8 Model output information and performance details . 7 Annex A Description of the ITU-T G.1071 model algorithm for HR application area 9 A.1 Audio module . 9 A.2 Video module . 11 A.3 Audiovisual module 16 Annex B Description of the ITU-T G.1071 model algorithm for LR application area 17 B.1 Audio
22、 module . 17 B.2 Video module . 19 B.3 Audiovisual module 24 Rec. ITU-T G.1071 (06/2015) 1 Recommendation ITU-T G.1071 Opinion model for network planning of video and audio streaming applications 1 Scope This Recommendation provides models which deliver estimates of the impact of typical IP network
23、impairments on the quality experienced by the end user in multimedia mobile streaming and IPTV applications over transport formats such as: RTP (over UDP), MPEG2-TS (over UDP or RTP/UDP), 3GPP-PSS (over RTP). The models are network planning tools. They are of help in selecting IP-network transmissio
24、n settings such as the audio and video format, the audio and video codecs and the audio and video bitrates, under the assumption that the network is prone to packet loss. This Recommendation targets the same services as ITU-T P.1201 and ITU-T P.1202. In particular, this Recommendation covers the sam
25、e coding technologies and unreliable network mechanisms such as user datagram protocol (UDP). However, this Recommendation is limited to QoE/QoS planning, while ITU-T P.1201 and ITU-T P.1202 are dedicated to service monitoring and benchmarking. The following Recommendations have also been developed
26、for QoE/QoS planning, but for different applications: ITU-T G.107: speech (telephone band) ITU-T G.107.1: speech (wideband) ITU-T G.1070: videophone ITU-T G.1030: Appendix II: web browsing For a summary of the services, encoding and network characteristics covered by the ITU-T G.1071 model algorithm
27、s, refer to Table 1 of clause 6. 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other
28、references are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The refer
29、ence to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T G.107 Recommendation ITU-T G.107 (2015), The E-model: a computational model for use in transmission planning. ITU-T G.1030 Recommendation ITU-T G.1030 (2014), Estimating e
30、nd-to-end performance in IP networks for data applications. ITU-T G.1070 Recommendation ITU-T G.1070 (2012), Opinion model for video-telephony applications. ITU-T H.264 Recommendation ITU-T H.264 (2014), Advanced video coding for generic audiovisual services. ITU-T P.800.1 Recommendation ITU-T P.800
31、.1 (2006), Mean Opinion Score (MOS) terminology. ITU-T P.910 Recommendation ITU-T P.910 (2008), Subjective video quality assessment methods for multimedia applications. 2 Rec. ITU-T G.1071 (06/2015) ITU-T P.911 Recommendation ITU-T P.911 (1998), Subjective audiovisual quality assessment methods for
32、multimedia applications. ITU-T P.1201 Recommendation ITU-T P.1201 (2012), Parametric non-intrusive assessment of audiovisual media streaming quality. ITU-T P.1202 Recommendation ITU-T P.1202 (2012), Parametric non-intrusive bitstream assessment of video media streaming quality. ITU-T P.1401 Recommen
33、dation ITU-T P.1401 (2012), Methods, metrics and procedures for statistical evaluation, qualification and comparison of objective quality prediction models. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following term defined elsewhere: 3.1.1 mean opinion score (MOS) ITU-T P
34、.800.1: The mean of opinion scores, i.e., of the values on a predefined scale that subjects assign to their opinion of the performance of the telephone transmission system used either for conversation or for listening to spoken material. 3.2 Terms defined in this Recommendation This Recommendation d
35、efines the following terms: 3.2.1 model, model algorithm: An algorithm used for estimating the subjective (perceived) quality of a media sequence. 3.2.2 sequence: A short decoded audio, video or audiovisual portion of a stream, typically shorter than 30 seconds. 3.2.3 compression artefacts: Artefact
36、s that are introduced due to lossy compression of the encoding process. 3.2.4 slicing artefacts: Artefacts that are introduced when packet losses are concealed through use of a packet loss concealment (PLC) scheme to repair erroneous frames. 3.2.5 freezing artefacts: Artefacts that are introduced wh
37、en the packet loss concealment (PLC) scheme of the receiver replaces the erroneous frames (either due to packet loss or error propagation) with the previous error-free frame until a decoded picture without errors has been received. Since the erroneous frames are not displayed, this type of artefact
38、is also referred to as freezing with skipping. 4 Abbreviations and acronyms This Recommendation uses the following abbreviations and acronyms: AAC Advanced Audio Coding AAC-LC Advanced Audio Coding Low Complexity AC3 Audio Coding 3 ACR Absolute Category Rating AMR-NB Adaptive Multi-Rate Narrowband A
39、MR-WB Adaptive Multi-Rate Wideband ARQ Automatic Repeat Request DASH Dynamic Adaptive Streaming over HTTP Rec. ITU-T G.1071 (06/2015) 3 FB Fullband FEC Forward Error Correction GOP Group Of Pictures HD High Definition (television) HE-AAC High-Efficiency Advanced Audio Coding HR Higher Resolution HRC
40、 Hypothetical Reference Circuit HTTP Hypertext Transfer Protocol HVGA Half Video Graphics Array LR Lower Resolution MBMS Multimedia Broadcast/Multicast Service MOS Mean Opinion Score MPEG Motion Pictures Expert Group NB Narrowband NTSC National Television Standard Committee PAL Phase Alternating Lin
41、e PCC Pearson Correlation Coefficient PES Packetized Elementary Stream PLC Packet Loss Concealment PVS Processed Video Sequence QCIF Quarter Common Intermediate Format QoE Quality of Experience QVGA Quarter Video Graphics Array RMSE Root Mean Square Error RTP Real-time Transport Protocol SD Standard
42、 Definition SRC Source Reference Channel or Circuit SWB Superwideband TS Transport Stream UDP User Datagram Protocol VSP Visual Simple Profile WB Wideband 5 Conventions None. 4 Rec. ITU-T G.1071 (06/2015) 6 Areas of application Table 1 below shows the application range of the models based on what th
43、e models have actually been developed for. Table 1 Factors and application ranges of the ITU-T G.1071 model algorithm ITU-T G.1071 Lower resolution (LR) ITU-T G.1071 Higher resolution (HR) Application information Value range, unit Sequence duration (Ts) It is expected that the model will give reliab
44、le prediction results for sequence durations within the range 8-24 seconds It is expected that the model will give reliable prediction results for sequence durations of approximately 8-16 seconds Packetization 3GPP MBMS, PSS or using RTSP directly (all three over RTP/UDP/IP) MPEG2-TS/RTP/UDP/IP RTP/
45、UDP/IP (Note 3) MPEG2-TS/UDP/IP (Note 3) Video codec MPEG4 visual simple profile (VSP) ITU-T H.264 baseline profile ITU-T H.264 main profile, ITU-T H.264 high profile Video size QCIF, QVGA, HVGA SD: PAL, NTSC HD: 720p, 1080p, 1080i (High profile: 1080; main profile: 720, SD) Audio codec AMR-NB, AMR-
46、WB+, AAC-LC, HE-AAC (v1, v2) MPEG-4 AAC-LC MPEG-4 HE-AAC (V1 and V2 = 3GPP enhanced AAC+) MPEG-1 Layer 2 AC3 Coded video bitrate ITU-T H.264 QCIF: 32-1000 kbit/s QVGA: 80-3000 kbit/s HVGA: 192-6000 kbit/s MPEG4 QCIF: 40-1500 kbit/s QVGA: 90-3500 kbit/s HVGA: 192-6000 kbit/s HD ITU-T H.264: 0.5 up to
47、 30 Mbit/s SD ITU-T H.264: 0.5 up to 9 Mbit/s Coded audio bitrate AMR-NB: 4.75-12.2 kbit/s AMR-WB+: 10.4-48 kbit/s AAC-LC: 16-128+ kbit/s HE-AAC (v1, v2): 32-128 kbit/s AAC-LC:32-576 kbit/s HE AACv2: 16-96 kbit/s MPEG-1 Layer 2: 64-384 kbit/s AC3:64-384 kbit/s Rec. ITU-T G.1071 (06/2015) 5 Table 1 F
48、actors and application ranges of the ITU-T G.1071 model algorithm ITU-T G.1071 Lower resolution (LR) ITU-T G.1071 Higher resolution (HR) Application information Value range, unit Video decoder packet loss concealment Two types of assumed decoder behaviour are covered: 1) freezing with skipping; 2) s
49、licing with: MPEG4: 1 slices/frame ITU-T H.264: 1 slice/packet Both MPEG4 and ITU-T H.264: Fixed PLC (using fixed decoder, details and settings) Types of decoder behaviour: two dimensions: slicing, PLC 1) freezing with skipping (duration(source)=duration(processed sequence); 2) slicing with 1 slice per frame; 3) slicing with 1 slice per macroblock row, PLC with zero-motion copy (temporal from same region of previous good frame). Audio decoder pac
