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SCALABLE VIDEO CODING GUIDELINES AND PERFORMANCE EVALUATIONS

FOR ADAPTIVE MEDIA DELIVERY

OF HIGH-DEFINITION CONTENT

Michael Grafl et al.SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of

HD Content

Michael Grafl, Christian Timmerer, Hermann Hellwagner, Wael Cherif, Daniel Negru, Stefano Battista

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OUTLINE Introduction

Scalable Video Coding Objectives

Encoding Recommendations Multi-Bitrate Streaming of Single-Layer Formats Deduced Recommendations for SVC

High-Definition SVC Encoding Performance Test-bed Setup Rate Control Modes Combining of Spatial and Quality Scalability Number of Quality Layers Requantization of Quality Layers

ConclusionsMichael Grafl et al.

SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of HD Content

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INTRODUCTION Scalable Video Coding (SVC) extension of H.264/AVC

Enables easy (in-network) adaptation of videos Temporal scalability (inherited from AVC) Spatial scalability Quality (SNR) scalability

Layered video coding Base layer (AVC-compatible) + enhancement layers

~10% coding overhead per layer compared to AVC

Encoding configurations must be chosen carefully Existing SVC studies rarely consider configurations of real

industry streaming systemsMichael Grafl et al.

SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of HD Content

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SCALABLE VIDEO CODING FRAMEWORK

Michael Grafl et al.SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of

HD Content

Quality

ResolutionFrame rate Which bitrates?

Which resolutions?

Number of layers?

Combination of layers?

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OBJECTIVES Devise SVC encoding guidelines

Deduce common resolutions and bitrates from industry solutions

Focus on HD content for adaptive media streaming

Evaluate various SVC configurations and encoders

Michael Grafl et al.SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of

HD Content

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MULTI-BITRATE STREAMING SOLUTIONS

Prominent streaming solutions providing AVC encoding recommendations Apple HTTP Live Streaming Adobe HTTP Dynamic Streaming Microsoft Smooth Streaming YouTube MTV

Recommendations were analyzed, aggregated and adjusted for SVC streaming

Full list of 26 resolutions & (even more) bitrates: http://alicante.itec.aau.at/am1.html

Michael Grafl et al.SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of

HD Content

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BITRATE RECOMMENDATIONS FOR AVC

ResolutionSuggested bitrates (4 streams) [Mbps]

Suggested bitrates

(2 streams) [Mbps]

1920x1080 8, 6, 5, 4 8, 5.5

1280x720 6, 4, 2.5, 1.5 4.5, 2.5

704x576  [Intentionally left blank] 2, 1.2

960x540 [Intentionally left blank] 2.25, 1.8

640x360 [Intentionally left blank] 1.6, 0.6

352x288 1.5, 0.9, 0.45, 0.25 1.2, 0.3

176x144  [Intentionally left blank] 0.1, 0.05

Michael Grafl et al.SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of

HD Content

For SVC add: +0%+10%+20%+30% +10% +10%

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BITRATE RECOMMENDATIONS FOR SVC

ResolutionSuggested bitrates (4 bitrates) [Mbps]

Suggested bitrates

(2 bitrates) [Mbps]

1920x1080 10.4, 7.2, 5.5, 4 8.8, 6.05

1280x720 7.8, 4.8, 2.75, 1.5 5, 2.75

704x576  [Intentionally left blank] 2.2, 1.35

960x540 [Intentionally left blank] 2.5, 2

640x360 [Intentionally left blank] 1.75, 0.65

352x288 1.95, 1.1, 0.5, 0.25 1.3, 0.3

176x144  [Intentionally left blank] 0.1, 0.05

Michael Grafl et al.SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of

HD Content

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HD SVC ENCODING PERFORMANCE Evaluate different SVC layer configurations

Rate control modes (constant bitrate vs. fixed quantization parameter)

• Validate bitrate recommendations Combination of spatial and quality scalability (multiple

resolutions & multiple quality layers)• Pack everything into one stream or prefer one stream per

resolution? Number of quality layers

• How many layers are useful? Requantization of quality layers for fixed QP mode

(deltaQP between layers)Michael Grafl et al.

SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of HD Content

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} Industry solutions

HD SVC ENCODING SETUP 4 test sequences (1080p, 25 fps)

PedestrianArea, Dinner, DucksTakeOff, CrowdRun

4 test scenarios 2 quality metrics

PSNR Video Quality Metric (VQM): Better correlation with human

visual system

4 encoders JSVM (i.e., MPEG reference software) MainConcept Vanguard Software Solutions (VSS) bSoft

Michael Grafl et al.SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of

HD Content

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ENCODER COMPARISON & RATE CONTROL MODES

Michael Grafl et al.SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of

HD Content

PSNR VQM

fixed QP

CBR

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1920x10801280x720352x288176x144

ENCODER COMPARISON & BITRATE VALIDATION

Michael Grafl et al.SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of

HD Content

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COMBINING SPATIAL & QUALITY SCALABILITY

Michael Grafl et al.SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of

HD Content

960x528 1920x1056single stream

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NUMBER OF QUALITY LAYERS

Avg. bitrate overhead per layer: JSVM: 11.7% MainConcept: 15.2% VSS: 19.7% bSoft: 8.2%

Michael Grafl et al.SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of

HD Content

1 layer2 layers

3 layers4 layers

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REQUANTIZATION OF QUALITY LAYERS Bitrate distance between quality layers

Michael Grafl et al.SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of

HD Content

VQM VQM vs. PSNR

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CONCLUSIONS Investigated industry AVC encoding guidelines Devised SVC bitrate recommendations

Stable quality at all resolutions Number of quality layers influences coding overhead Several configurations and encoders evaluated

Future Work Integration in end-to-end streaming system Performance studies of Scalable HEVC (SHVC)

Follow-up paper targeting adaptive HTTP streaming: M. Grafl et al., "Hybrid Scalable Video Coding for HTTP-based Adaptive Media Streaming with High-Definition Content", Proc. IEEE WoWMoM, Madrid, Spain, June 2013.

Michael Grafl et al.SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of

HD Content

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THANKS FOR YOUR ATTENTION!

Questions?

Michael Grafl et al.SVC Guidelines & Performance Evaluations for Adaptive Media Delivery of

HD Content

http://itec.aau.at/~mgrafl | @MyKey_ – http://aau.at/tewi/inf/itec/mmc/ | @itecMMC