1. Name: Title:
Making Real-Time Video Work Over the Internet
Yair Wiener CTO October 2010

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. Video Compression
The Good, The Bad, and The Ugly
Uncompressed
HD 720p30
Compressed
HD 720p30

4. Typical IP Network Impairments
Corruption
Corrupted packet rejection
Multi-path
Collisions
BER
Congestion
Dropped by router / switch
Packet Loss

5. Typical IP Network Impairments
Jitter
TX
RX
T T+2Δ T+4Δ T+Δ

6. Handling IP Network Impairments
Packet Loss - Corruption
SVC + FEC
Packet Loss - Congestion
NetSense
Jitter, Out of Order
AJB

7. Handling Corruption
7

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. 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. 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. SVC - Error Resiliency
The layered structure of SVC allows Unequal Error
Protection (UEP)

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. Reliable Transmission - FEC
Protect SVC base layer
Dynamic FEC strength
FEC-XOR, FEC-RS

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. Example
SVC + FEC AVC

16. Handling Congestion
16

17. NetSense
Classify network condition (congestion Vs. corruption)
Estimate available BW
Adapt bit rate to prevent congestion

18. Performance
0
128
256
384
512
640
768
0 10 20 30 40 50 60 70
Bandwidth(Kbps)
Time (seconds)

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. Handling Jitter
20

21. Adaptive Jitter Buffer
Jitter
TX
RX
Buffer = 4Δ
RX
delayed

22. Where to Find Us?
Corporate site Community Blogs Newsletter twitter
This seminar, online:
http://community.radvision.com/page/futurecomm-2010/

23. Name: Title:Yair Wiener
yairw@radvision.com
CTO
Thank you!