Perceptual Evaluation of Video Quality (PEVQ) is an end-to-end (E2E) measurement algorithm to score the
picture quality of a video presentation by means of a 5-point
mean opinion score Mean opinion score (MOS) is a measure used in the domain of Quality of Experience and telecommunications engineering, representing overall quality of a stimulus or system. It is the arithmetic mean over all individual "values on a predefined scale t ...
(MOS). It is, therefore, a video quality model. PEVQ was benchmarked by the
Video Quality Experts Group (VQEG) in the course of the Multimedia Test Phase 2007–2008. Based on the performance results, in which the accuracy of PEVQ was tested against
ratings obtained by human viewers, PEVQ became part of the new International Standard.
[ITU-T Rec. J. 247]
(2008)
Application
The measurement algorithm can be applied to analyze visible artifacts caused by a digital video encoding/decoding (or transcoding) process, radio- or IP-based transmission networks and end-user devices. Application scenarios address
next generation networking
The next-generation network (NGN) is a body of key architectural changes in telecommunication core and access networks. The general idea behind the NGN is that one network transports all information and services (voice, data, and all sorts of med ...
and mobile services and include
IPTV
Internet Protocol television (IPTV) is the delivery of television content over Internet Protocol (IP) networks. This is in contrast to delivery through traditional terrestrial, satellite, and cable television formats. Unlike downloaded med ...
(
Standard-definition television and
HDTV
High-definition television (HD or HDTV) describes a television system which provides a substantially higher image resolution than the previous generation of technologies. The term has been used since 1936; in more recent times, it refers to the g ...
),
streaming video,
Mobile TV
Mobile television is television watched on a small handheld or mobile device. It includes service delivered via mobile phone networks, received free-to-air via terrestrial television stations, or via satellite broadcast. Regular broadcast stand ...
,
video telephony
Videotelephony, also known as videoconferencing and video teleconferencing, is the two-way or multipoint reception and transmission of audio signal, audio and video signals by people in different locations for Real-time, real time communication. ...
,
video conferencing
Videotelephony, also known as videoconferencing and video teleconferencing, is the two-way or multipoint reception and transmission of audio signal, audio and video signals by people in different locations for Real-time, real time communication. ...
and
video messaging.
The measurement paradigm is to assess degradations of a decoded video sequence output from the network (for example as received by a TV set top box) in comparison to the original reference picture (broadcast from the studio). Consequently, the setup is referred to as end-to-end (E2E) quality testing.
Algorithm
The development for picture quality analysis algorithms available today started with still image models which were later enhanced to also cover motion pictures. PEVQ is full-reference algorithm (see the classification of models in
video quality
Video quality is a characteristic of a video passed through a video transmission or processing system that describes perceived video degradation (typically, compared to the original video). Video processing systems may introduce some amount of dist ...
) and analyzes the picture pixel-by-pixel after a temporal alignment (also referred to as 'temporal registration') of corresponding frames of reference and test signal. PEVQ MOS results range from 1 (bad) to 5 (excellent) and indicate the perceived quality of the decoded sequence.
PEVQ is based on modeling the behavior of the human visual system. In addition to an overall MOS score, PEVQ quantifies abnormalities in the video signal by a variety of
KPIs, including
PSNR
Peak signal-to-noise ratio (PSNR) is an engineering term for the ratio between the maximum possible power of a Signal (information theory), signal and the power of corrupting noise that affects the fidelity of its representation. Because many sign ...
, distortion indicators and lip-sync delay.
See also
*
Mean opinion score Mean opinion score (MOS) is a measure used in the domain of Quality of Experience and telecommunications engineering, representing overall quality of a stimulus or system. It is the arithmetic mean over all individual "values on a predefined scale t ...
*
Peak signal-to-noise ratio
Peak signal-to-noise ratio (PSNR) is an engineering term for the ratio between the maximum possible power of a signal and the power of corrupting noise that affects the fidelity of its representation. Because many signals have a very wide dynamic ...
(PSNR)
*
Subjective video quality
Subjective video quality is video quality as experienced by humans. It is concerned with how video is perceived by a viewer (also called "observer" or "subject") and designates their opinion on a particular video sequence. It is related to the fiel ...
*
Video quality
Video quality is a characteristic of a video passed through a video transmission or processing system that describes perceived video degradation (typically, compared to the original video). Video processing systems may introduce some amount of dist ...
References
Further reading
ITU-T Rec. P.910 Subjective video quality assessment methods for multimedia applications
Wiley, March 2005,
PEVQ Paper MMSP 2007, IEEE 9th Workshop on Multimedia Signal Processing{dead link, date=August 2016
VQEG Multimedia Test Plan and Final ReportTesting MPEG based IP video QoE/QoS
External links
Film and video technology
Digital television
Video codecs
Codecs
Videotelephony
de:PEXQ#Perceptual Evaluation of Video Quality (PEVQ)