1. Advances in Network-adaptive Video Streaming Bernd Girod J. Chakareski, M. Kalman, Y. J. Liang, E. Setton, R. Zhang Information Systems Laboratory Department of Electrical Engineering Stanford University

5. Adaptive Media Playout Fixed deadline Flexible deadline Idea: reduce latency and packet loss simultaneously by continuously adapting playout deadline to network conditions 5% packet loss 2 sec average receiver buffer [Steinbach, F ärber, Girod, ICIP 2001]

8. Reduced Pre-roll Time for Stored Streams  G =1.092,  B =0.42, T G =20 sec, T B =2 sec, T RTT =220 ms Probability of buffer underflow < 1% [ Kalman, Steinbach , Girod, ISCAS 200 2 ]

9. Rate Scalability by Playout Speed Adjustment Server 20 kbps 50 kbps 95 kbps 25 kbps 55 kbps 100 kbps Channel (mean throughput) 85 kbps (29.2 dB, 53.3 kbps) (33.1 dB, 93.6*0.9=84.2 kbps)

10. First Things First: Smart Prefetching Idea: Send more important packets earlier to allow for more retransmissions Server Client Internet Request stream Rate-distortion preamble Prefetch times Video data Repeat request Repeat request Repeat request

12. Markov Decision Tree for One Packet ... N transmission opportunities before deadline send: 1 ack: 1 0 0 0 send: 1 0 send: 1 0 ack: 1 0 1 0 1 0 0 1 1 1 0 0 0 0 t current t current +  t t current +2  t Action Observation “ Policy“ minimizing J = D +  R

13. Packet Delay Jitter and Loss delay     pdf loss lead-time loss probability lead-time loss probability

17. R-D Optimized Streaming with a Proxy Server Last hop [Chakareski, Chou, Girod, Asilomar 2002, MMSP 2002] Media Server Switch/ Router Proxy Server Client Backbone Network Packet Receiver-driven RaDiO streaming Sender-driven RaDiO streaming Buffer packets

19. Streaming with Diversity Client Channel 1 Channel 2 Channel N Packet Path Diversity Server Diversity Media Server Client Channel 1 Channel 2 Channel N Media Server 1 Media Server 2 Media Server N

21. R-D Optimized Streaming with Accelerated Retroactive Decoding (ARD) Latency: 100 ms RTT: 100 ms PSNR, in dB Bit-Rate, in kbps 3 dB 47 %

22. R-D Optimized Streaming with Accelerated Retroactive Decoding (ARD) Latency: 100ms R-D Optimized Streaming with Accelerated Retroactive Decoding (ARD) Multiple Deadlines Rate: 68.8 kbps Mean PSNR: 27.0 dB Single Deadline Rate: 89.0 kbps Mean PSNR: 23.9 dB

24. Error Resilience vs. Coding Efficiency I P5 230 frames of Foreman coded using H.26L TML8.5. Average PSNR=33.4dB P1 P2

25. Rate-Distortion Optimal Reference Picture Selection [Wiegand, Färber, Girod, 2000] [Liang, Girod, 2002]

27. ORPS Performance over Time Axis

28. MaD Sequence at 10% packet loss No Retransmissions Optimal Reference Picture Selection Rate: 320 kbps Mean PSNR: 39.2 dB Adaptive I-Frame Insertion Rate: 320 kbps Mean PSNR: 38.2 dB