QoE Evaluation Methodology for HD Video Streaming using Social Networking 報告人:張景舜 作者:

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QoE Evaluation Methodology for HD Video
Streaming using Social Networking
報告人:張景舜
作者: Gardlo, B.; Ries, M. ; Rupp, M. ; Jarina, R.;Dept.
of Telecommun. & Multimedia, Univ. of Zilina, Zilina, Slovakia
I. INTRODUCTION
 Quality-of-Experience (QoE) and Social networks has gained
strong interest, both from a research and a commercial
perspective.
 Assessment methodologies are extremely time consuming
and poorly reflect ”real world” scenarios.
II. USER BASED ASSESSMENT
 Relationship between user, application and network.
 Absolute Category Rating (ACR)
II. USER BASED ASSESSMENT
 Influence factors of quality of experience(QoE)
III. CONTEXT INFLUENCE AND QOE
 Modern social networks rely not just on the messaging
concept
 46% of them are under 25 years old and another 26% is
under 35 years.
III. CONTEXT INFLUENCE AND QOE
 A. Audiovisual content
 SPATIAL AND TEMPORAL CHARACTERISTICS OF CONTENT CLASSES
 B. Social and Cultural Aspects
IV. TECHNICAL SYSTEM
 A. Encoder settings
 Audio content was encoded using an AAC codec with 48 kHz
sampling rate and 96 kbit/s bit rate.
 Each of these sequences was further encoded into five equally
distanced video bit rates, 2 Mbit/s for the best quality, and 800
kbit/s for the lowest quality (300 kbit/s step size).
IV. TECHNICAL SYSTEM
 B. End User Devices
 Targeting our QoE assessment application on the HD multimedia
content, we cannot guarantee that this content will be also
watched on native HD capable screens.
 About 50% of the users use resolutions of 1024x768, 1280x800
or similar.
V. QOE ASSESSMENT
A.
Statistical relevance of
obtained subjective
evaluations
V. QOE ASSESSMENT
 評估方法
 s : sample variance
 d : accuracy parameter
(allowed error in estimation)
 x^: sample mean
 μ : true population mean
 n : minimum sample size
V. QOE ASSESSMENT
 B. Assessment results
Action movie 800 kbit/s MOS Histogram. Action movie 2000kbit/s MOS Histogram.
V. QOE ASSESSMENT
 MOS values with their 95% confidence intervals.
VI. CONCLUSION
 The methodology provides a high applicability for subjective
testing of the multimedia services with respect to real usage
scenarios.
 With the social data available throughout the social network, we
can target certain specific user groups, with no need of
performing exhausting social studies.
 All these facts support the high statistical significance of the results.
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