Dynamic Adaptive Streaming over HTTP (DASH) is a convenient approach to transfer videos in an adaptive and dynamic way to the user. As a consequence, this system provides high bandwidth flexibility and is especially suitable for mobile use cases where the bandwidth variations are tremendous. In this paper we have integrated the Scalable Video Coding (SVC) extensions of the Advanced Video Coding (AVC) standard into the recently ratified MPEG-DASH standard. Furthermore, we have evaluated our solution under restricted conditions using bandwidth traces from mobile environments and compared it with an improved version of our MPEG-DASH implementation using AVC as well as major industry solutions.

1. USING SCALABLE VIDEO CODING FOR
DYNAMIC ADAPTIVE STREAMING OVER
HTTP IN MOBILE ENVIRONMENTS
Christopher Mueller, *Daniele Renzi, Stefan Lederer, *Stefano Battista and Christian Timmerer
Alpen-Adria Universität Klagenfurt (AAU)  Faculty of Technical Sciences (TEWI)
Institute of Information Technology (ITEC)  Multimedia Communication (MMC)
*bSoft ltd, Italy
EUSIPCO 2012 - 31.08.2012
Christopher Mueller Using SVC for DASH in Mobile Environments 1

2. OUTLINE
 Motivation
 Introduction of Dynamic Adaptive Streaming over HTTP
with Scalable Video Coding
 Integration of SVC into MPEG-DASH
 Adaptation Logic
 Methodology and Experimental Setup
 Evaluation Results and Comparison
 Conclusion
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3. MOTIVATION
 Real-Time Entertainment is accounting for more than 50% of the
whole internet traffic
 HTTP is the major protocol and used for a variety of services
 Already entered a Post-PC era even for fixed access networks
and mobile multimedia
traffic still grows tremendously
 Although problems exists:
 Firewall and NAT traversal
 No reuse of the internet
infrastructure, e.g., proxies, CDN’s
 Fluctuating bandwidth conditions
especially in mobile networks
 Multiple annoying rebuffering
events
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4. DYNAMIC ADAPTIVE STREAMING
OVER HTTP
 Media Presentation Description (MPD)
 Dynamic adaption to the network conditions
 Reuse of existing Internet infrastructure
 Has the potential to play a major role in future networks
optimizations are crucial
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5. INTRODUCTION DASH & SVC
 Integration of Scalable Video Coding into MPEG-DASH
 Potential advantages due to the layered architecture
 More flexibility for the segment selection (cancelation of segments)
 Adaptation logic based on an explorative specified buffer model
 Evaluation and comparison of MPEG-DASH SVC with the major
industry solutions (Microsoft, Apple, Adobe) and our MPEG-DASH
AVC implementation
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6. INTEGRATION OF SVC INTO DASH
 Content has been encoded with the BSoft SVC encoder at 14
different bitrates from 100kbps to 4500kbps
 Same source content has been used for all other experiments
 Media stored on the server without any further container
format to support media bitrates lower than 1Mbps [1]
 Reordering of the NAL units on the client side
This is more efficient than having the NAL units stored in
decoding order on the server
[1] I. Kofler, R. Kuschnig, H. Hellwagner, “Implications of the ISO Base Media File
Format on Adaptive HTTP Streaming of H.264/SVC,” In Proc. of 9th IEEE Consumer
Communications and Networking Conference, Los Alamitos, CA, USA, Jan. 2012.
Christopher Mueller Using SVC for DASH in Mobile Environments 6

7. ADAPTATION LOGIC
 Based on the available bandwidth and the current state of the
buffer – explorative specified
 The model must be fitted to the network conditions
 SVC model is more aggressive
Christopher Mueller Using SVC for DASH in Mobile Environments 7

8. METHODOLOGY AND EXPERIMENTAL
SETUP
 3 Tracks / Experiments based on mobile freeway traces
 Evaluation Network
 Bandwidth shaping with Linux tc
 Static RTT of 150ms
 Metrics
 Average bitrate
 Number of quality switches
 Buffer level
 Number of unsmooth seconds
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9. MPEG-DASH AVC
 Adaptation process is very stable
 Adaptation reacts accurately, e.g., Second 190
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10. MPEG-DASH SVC
 Better bandwidth utilization than AVC without stalls and a
quite stable buffer
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11. COMPARISON
Name Average Average Switches Average Unsmoothness
Bitrate [kbps] [Number of Switches] [Seconds]
Microsoft [2] 1522 51 0
Adobe [2] 1239 97 64
Apple [2] 1162 7 0
MPEG-DASH [2] 1464 166 0
MPEG-DASH AVC 2341 81 0
MPEG-DASH SVC 2738 101 0
[2] C. Mueller, S. Lederer and C. Timmerer, “An Evaluation of Dynamic Adaptive
Streaming over HTTP in Vehicular Environments”, In Proceedings of the 4th ACM
Workshop on Mobile Video, Chapel Hill, North Carolina, February 24, 2012.
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12. CONCLUSION
 SVC achieves a higher bandwidth utilization of
approximately 15% compared to AVC
 Mapping the adaption process smoothly to the buffer
increases the streaming performance
 However PSNR of SVC is quite low
 Future work
 will include a configuration with multiple baselayers (one for
each major device class/resolution)
 Improvement of the adaptation logic
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13. THANK YOU FOR YOUR ATTENTION
… questions, comments, etc. are welcome …
Christopher Mueller | dash.itec.aau.at
Alpen-Adria Universität Klagenfurt (AAU)  Faculty of Technical Sciences (TEWI)
Institute of Information Technology (ITEC)  Multimedia Communication (MMC)
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