FutureComm 2010: Making Real-Time Video Work Over the Internet

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FutureComm 2010: Making Real-Time Video Work Over the Internet

  1. 1. Name: Title: Making Real-Time Video Work Over the Internet Yair Wiener CTO October 2010
  2. 2. Gopher, FTP WWW P2P Video Content Video Communication 1993-1995 1995-2000 2000-2013 2013-2025 2025+ 1995: Web overtakes Gopher, FTP 2000: Peer-to-Peer overtakes Web 2013: Video Content overtakes Peer-to-Peer 2025: Video Communication overtakes Video Content Source: Cisco 2010 Dominant Traffic Types
  3. 3. Video Compression The Good, The Bad, and The Ugly Uncompressed HD 720p30 Compressed HD 720p30
  4. 4. Typical IP Network Impairments Corruption Corrupted packet rejection Multi-path Collisions BER Congestion Dropped by router / switch Packet Loss
  5. 5. Typical IP Network Impairments Jitter TX RX T T+2Δ T+4Δ T+Δ
  6. 6. Handling IP Network Impairments Packet Loss - Corruption SVC + FEC Packet Loss - Congestion NetSense Jitter, Out of Order AJB
  7. 7. Handling Corruption 7
  8. 8. Scalable Video Coding – The Promise Generate a single video stream that can serve multiple users “One ring to rule them all” The Lord of the Rings, J.R.R Tolkein
  9. 9. Scalability of Video - Modalities Temporal - Change of frame rate (e.g 30 FPS, 15 FPS) Spatial - Change of resolution (e.g 720p, 480p, CIF) Fidelity / SNR - Change of quality (e.g 1 Mbps, 512 kbps) 0 20 40 0 500 1000 0 500 1000 1500 FPSResolution (H lines) Bitrate(Kbps)
  10. 10. Video Layered Structure Base Layer (e.g qCIF@15 FPS) Enhancement Layer (e.g CIF@30 FPS) Enhancement Layer (e.g 4CIF@30 FPS) Single Layer (e.g 4CIF@30 FPS) SVC H.264
  11. 11. SVC - Error Resiliency The layered structure of SVC allows Unequal Error Protection (UEP)
  12. 12. Reliable Transmission - FEC 0 1 1 0 0 0 0 1 a 0 1 1 0 0 0 0 1 1 0 0 1 1 1 1 0 0 0 0 0 0 0 1 10
  13. 13. Reliable Transmission - FEC Protect SVC base layer Dynamic FEC strength FEC-XOR, FEC-RS
  14. 14. Quality 20 25 30 35 40 45 0 1 2 3 4 5 6 7 8 9 PSNR(dB) Pakcet loss rate (%) PSNR Vs. Packet loss rate SVC H.264
  15. 15. Example SVC + FEC AVC
  16. 16. Handling Congestion 16
  17. 17. NetSense Classify network condition (congestion Vs. corruption) Estimate available BW Adapt bit rate to prevent congestion
  18. 18. Performance 0 128 256 384 512 640 768 0 10 20 30 40 50 60 70 Bandwidth(Kbps) Time (seconds)
  19. 19. Quality of Experience Latency Performance * G.1070 score - The higher the score, the better the quality * The lower the latency, the better the quality 1 1.5 2 2.5 3 3.5 4 4.5 Videoquality(1-5) NetSense Google Talk Microsoft OCS (2.0.6362.36) 1 10 100 1000 Latency(milliseconds) NetSense Google Talk Microsoft OCS (2.0.6362.36)
  20. 20. Handling Jitter 20
  21. 21. Adaptive Jitter Buffer Jitter TX RX Buffer = 4Δ RX delayed
  22. 22. Where to Find Us? Corporate site Community Blogs Newsletter twitter This seminar, online: http://community.radvision.com/page/futurecomm-2010/
  23. 23. Name: Title:Yair Wiener yairw@radvision.com CTO Thank you!

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