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 J.343.5 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (11/2014) SERIES J: CABLE NETWORKS AND TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS Measurement of the quality of service Part 3 Hybrid-FRe
2、 objective perceptual video quality measurement for HDTV and multimedia IP-based video services in the presence of a full reference signal and encrypted bitstream data Recommendation ITU-T J.343.5 Rec. ITU-T J.343.5 (11/2014) i Recommendation ITU-T J.343.5 Hybrid-FRe objective perceptual video quali
3、ty measurement for HDTV and multimedia IP-based video services in the presence of a full reference signal and encrypted bitstream data Summary Recommendation ITU-T J.343.5 provides hybrid full-reference encrypted (Hybrid-FRe) objective perceptual video quality measurement methods for HDTV and multim
4、edia when a full reference signal and encrypted bitstream data are available. The following are example applications that can use this Recommendation: potentially real-time, in-service quality monitoring at the headend; video television streams over cable/IPTV networks including those transmitted ov
5、er the Internet using Internet protocol; video quality monitoring at the receiver when a full reference signal and encrypted bitstream data are available; video quality monitoring at measurement nodes located between point of transmission and point of reception when a full reference signal and encry
6、pted bitstream data are available; quality measurement for monitoring of a transmission system that utilizes video compression and decompression techniques, either a single pass or a concatenation of such techniques; lab testing of video transmission systems. This Recommendation includes an electron
7、ic attachment containing test vectors, including video sequences, bitstream files and predicted objective model scores. History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T J.343.5 2014-11-29 9 11.1002/1000/12320 _ * To access the Recommendation, type the URL http:/handle.itu.int
8、/ 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 J.343.5 (11/2014) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommun
9、ications, 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 Recommendations on them with a view to standardizing telecommunic
10、ations 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 approval of ITU-T Recommendations is covered by the procedur
11、e 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 “Administration“ is used for conciseness to indicate both a telecomm
12、unication 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 compliance with the Recommendation is achieved when all of these
13、 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 required of any party. INTELLECTUAL PROPERTY RIGHTSITU dr
14、aws 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 Intellectual Property Rights, whether asserted by ITU members
15、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. However, implementers are cautioned that this may not repres
16、ent 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 prior written permission of ITU. Rec. ITU-T J.343.5 (11/20
17、14) iii Table of Contents Page 1 Scope . 1 1.1 Applications 2 1.2 Limitations 2 2 References . 3 3 Definitions 3 3.1 Terms defined elsewhere 3 3.2 Terms defined in this Recommendation . 3 4 Abbreviations and acronyms 3 5 Conventions 4 6 Performance metrics . 4 7 Description of the hybrid full-refere
18、nce methodology . 4 8 Models 5 Annex A Description of video quality measure PEVQ-S (e) . 6 A.1 Introduction 6 A.2 Description of the PEVQ-S (e) algorithm 6 Annex B YHyFRe . 37 B.1 Introduction 37 B.2 Hybrid-FRe VQM computation . 37 Bibliography. 41 Electronic attachment: Test vectors, including vide
19、o sequences, bitstream files and predicted objective model scores. Rec. ITU-T J.343.5 (11/2014) 1 Recommendation ITU-T J.343.5 Hybrid-FRe objective perceptual video quality measurement for HDTV and multimedia IP-based video services in the presence of a full reference signal and encrypted bitstream
20、data 1 Scope This Recommendation1 describes algorithmic models for measuring the visual quality of IP-based video services. The models are hybrid full-reference encrypted (Hybrid-FRe) models, which use the unimpaired reference video signal, packet header information, and video image data captured at
21、 the video player. The models operate without parsing or decoding the packet payload. Thus, these models can be used with encrypted bitstream data as well as non-encrypted bitstream data. As output the models provide an estimate of visual quality on the 1,5 difference mean opinion score (DMOS) scale
22、, derived from five-point absolute category rating (ACR) as in ITU-T P.910. The models address low-resolution (VGA/WVGA) application areas, including services such as mobile TV, as well as high-resolution (HD) application areas, including services such as IPTV. This Recommendation is to be used with
23、 videos encoded using ITU-T H.264 and media payload encapsulated in RTP/UDP/IP packets for the low resolution and encapsulated in MPEG-TS/RTP/UDP/IP for the high resolution. The models in this Recommendation measure the visual effect of spatial and temporal degradations as a result of video coding,
24、erroneous transmission or video rescaling. The models may be used for applications such as to monitor the quality of deployed networks to ensure their operational readiness or to benchmark service quality. The models in this Recommendation can also be used for lab testing of video transmission syste
25、ms. The models identified in this Recommendation have limited precision. Therefore, directly comparing model results can be misleading. The accuracy of models has to be understood and taken into account (e.g., using ITU-T J.149). The validation test material consisted of video encoded using differen
26、t implementations of ITU-T H.264. It included media transmitted over wired and wireless networks, such as WIFI and 3G mobile networks. The transmission impairments included error conditions such as dropped packets, packet delay, both from simulations and from transmission over commercially operated
27、networks. The following source reference channel (SRC) conditions were included in the validation test: 1080i 60 Hz (29.97 fps); 1080p (25 fps); 1080i 50 Hz (25 fps); 1080p (29.97 fps); SRC duration: HD: 10s, VGA/WVGA: 10 s or 15 s (rebuffering); VGA at 25 and 30 fps; WVGA at 25 and 30 fps. _ 1 This
28、 Recommendation includes an electronic attachment containing test vectors, including video sequences, bitstream files and predicted objective model scores. 2 Rec. ITU-T J.343.5 (11/2014) The following hypothetical reference circuit (HRC) conditions were included in the validation test for each resol
29、ution: Test factors Video resolution: 1920x1080 interlaced and progressive Video frame rates 29.97 and 25 fps Video bitrates: 1 to 30 Mbit/s (HD), 100kbit/s to 3 Mbit/s (VGA/WVGA) Temporal frame freezing (pausing with skipping) of up to 50% of video duration Transmission errors with packet loss Rebu
30、ffering (VGQ/WVGA only): up to 50% of SRC Coding technologies ITU-T H.264/AVC (MPEG-4 Part 10) Tandem coding 1.1 Applications The applications for the estimation model described in this Recommendation include, but are not limited to: potentially real-time, in-service quality monitoring at the headen
31、d; video television streams over cable/IPTV networks including those transmitted over the Internet using Internet protocol; video quality monitoring at the receiver when a copy of the unimpaired reference video and the encrypted bitstream data are available; video quality monitoring at measurement n
32、odes located between point of transmission and point of reception when a copy of the unimpaired reference video and the encrypted bitstream data are available; quality measurement for monitoring of transmission systems that utilize video compression and decompression techniques, including concatenat
33、ions of such techniques; lab testing of video transmission systems. 1.2 Limitations The video quality estimation models described in this Recommendation cannot be used to fully replace subjective testing. When frame freezing was present, the test conditions had frame freezing durations up to 50% of
34、SRC duration. The models in this Recommendation were validated for measuring video quality in a re-buffering condition (i.e., video that has a steadily increasing delay or freezing without skipping) only for VGA/WVGA. The models were not tested on other frame rates than those used in TV systems (i.e
35、., 29.97 fps and 25 fps, in interlaced or progressive mode). If forward error correction techniques are employed, the models in this Recommendation may not be used. It is important that no additional transmission errors occur between the collection point of the bitstream data and the capture point o
36、f the processed video sequence (PVS). It should be noted that in case of new coding and transmission technologies producing artifacts, which were not included in this evaluation, the objective model may produce erroneous results. Here, a subjective evaluation is required. Rec. ITU-T J.343.5 (11/2014
37、) 3 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 references are subject to rev
38、ision; 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 reference to a document within thi
39、s Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T H.264 Recommendation ITU-T H.264 (2014), Advanced video coding for generic audiovisual services. ITU-T J.149 Recommendation ITU-T J.149 (2004), Method for specifying accuracy and cross-calibration of
40、Video Quality Metrics (VQM). ITU-T J.342 Recommendation ITU-T J.342 (2011), Objective multimedia video quality measurement of HDTV for digital cable television in the presence of a reduced reference signal. ITU-T J.343 Recommendation ITU-T J.343 (2014), Hybrid perceptual bitstream models for objecti
41、ve video quality measurements. ITU-T P.910 Recommendation ITU-T P.910 (2008), Subjective video quality assessment methods for multimedia applications. ITU-R BT.601 Recommendation ITU-R BT.601 (2011), Studio encoding parameters of digital television for standard 4:3 and wide screen 16:9 aspect ratios
42、. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following terms defined elsewhere: 3.1.1 hybrid full reference model ITU-T J.343: An objective video quality model that predicts subjective quality using the reference video, the decoded video frames, packet headers, and the vi
43、deo payload. Such models cannot analyse encrypted video. 3.1.2 hybrid full reference encrypted model ITU-T J.343: An objective video quality model that predicts subjective quality using the reference video, the decoded video frames, and packet headers. Such models are suitable for use with encrypted
44、 video. 3.2 Terms defined in this Recommendation None. 4 Abbreviations and acronyms This Recommendation uses the following abbreviations and acronyms: CODEC Coder-Decoder DMOS Difference Mean Opinion Score DTS Decoding Time Stamp FR Full Reference HRC Hypothetical Reference Circuit HVS Human Visual
45、System 4 Rec. ITU-T J.343.5 (11/2014) Hybrid-FR Hybrid Full Reference Hybrid-FRe Hybrid Full Reference Encrypted LUT Look-Up Table MOS Mean Opinion Score MPEG Moving Picture Experts Group MSE Mean Square Error PES Packetized Elementary bitStream PEVQ-S Perceptual Evaluation of Video Quality for Stre
46、aming PTS Presentation Time Stamp PVS Processed Video Sequence ROI Region Of Interest SEQ Sequence index SRC Source Reference Channel (or Circuit) TS Transport Stream VQEG Video Quality Experts Group VQM Video Quality Metrics 5 Conventions None. 6 Performance metrics A summary of this and other hybr
47、id models may be found in ITU-T J.343. See b-VQEG Hybrid for the complete analysis of the models included in this Recommendation. 7 Description of the hybrid full-reference methodology This Recommendation specifies objective video quality measurement methods that use both processed video sequences a
48、nd bitstream data. The bitstream data may be provided in the forms of elementary bitstream (ES), packetized elementary bitstream (PES) or packet video (Figure 1). In addition, the Hybrid-FRe models also use reference video sequences. Figure 2 shows a Hybrid-FRe model. The Hybrid-FRe models need the
49、source video sequence (SRC). While the Hybrid-FR models have access to all of this data, the Hybrid-FRe models do not have access to the video payload. Therefore, these models can be used with encrypted bitstreams. Rec. ITU-T J.343.5 (11/2014) 5 .J. 3 4 3 . 5 (1 4 )_ F 0 1E n co d erC h an n el“E “l em en t ar y s t re am (E S)“ “or p ac k et i ze d el em en t ar y s t re am (PE S)“ “or p ac k et v i d eoD ec o d erH y b ri d p er ce p t u al /b i
