Dongju Lee and Hwangjun Song IEEE TRANSACTIONS ON MULTIMEDIA, VOL. 13, NO. 4, AUGUST 2011

1. A Robust Luby Transform Encoding Pattern-Aware Symbol Packetization Algorithm for Video Streaming Over Wireless Network DongjuLee and Hwangjun Song IEEE TRANSACTIONS ON MULTIMEDIA, VOL. 13, NO. 4, AUGUST 2011

2. Outline • Introduction • LT Encoding Pattern-Aware Symbol Relationship Analysis • Packetization Algorithm of LT Encoded Symbols • Performance Analysis • Experimental Results • Conclusion

3. Introduction • To minimize the quality degradation of video streaming service caused by packet losses over wireless network. • Minimize packet loss effects by reducing the dependency among packets conveying Lubytransform encoded symbols. • The LT decoding success rate can be improved at the receiver by minimizing the effect of a lost packet.

4. Introduction

5. LT Encoding Pattern-Aware Symbol Relationship Analysis and the element of have a strong dependency on each other.

6. LT Encoding Pattern-Aware Symbol Relationship Analysis • Property1：The decoding success rate of the root can be improved by assigning {, 1} to different packets. • Property2 ：The decoding success rate of the source symbols in can be increased if more symbols of are available. • Property3：The decoding success rate of the root can be enhanced by packetizing and the elements of its into the same packet.

7. Packetization Algorithm of LT Encoded Symbols • The proposed packetization algorithm is designed to insert more elements of and into the same packet. ：the subset of are put into the same packet with ：determine the number of elements of that are packetized with min{() , ||} and

8. Packetization Algorithm of LT Encoded Symbols • Step 0: Select the first source symbol as a root. • Step 1 :Select a with in { ,1} of the root thathas not been assigned to any packet until now (if all , 1 are already packetized, go directly to Step 4). • Step 2 : Put the into the target packet chosen by the following rules (Rule ihas a higher priority than Rule (i+1)). If any packet is not chosen by the rules below, go to Step 4.

9. Packetization Algorithm of LT Encoded Symbols • Rule 1: If an empty packet exists, choose the packet as the target packet. • Rule 2:If the available space at a packet is not less than (e.g., if and elements of can be inserted into the same packet), then choose the packet as the target packet. • Rule 3: when andelements of cannot be inserted into the same packet, if is less than and the available space at a packet is not less than , then choose the packet as the target packet with = in order to insert and elements in into the same packet as the best alternative policy of Rule 2

10. Packetization Algorithm of LT Encoded Symbols • Step 4 : Sequentially selected next source symbol as a root and repeat Step 1-3 with new root and the initial until no more root exist, go to Step 5. • Step 5 : Randomly distribute the remaining encoded symbols into residual spaces of the packets.

11. Packetization Algorithm of LT Encoded Symbols • Step 3:Determine a by randomly choosing elements in . Put into the target packet as shown in Fig. 3. • Step 4: Select source symbol sequentially as a root and repeat Step 1–3 with the new root and the initial until no more root exit, go to Step 5. • Step 5:Randomly distribute the remaining encoded symbols into the residual spaces of the packets.

12. Performance Analysis • Performance measure：The number of the successfully received elements of with . • Claim：|| > || ：the number of transmitted packets (> ) ： the number of encoded symbols the average number of symbols in the target packet when the remaining symbols are randomly allocated to packet.

13. Performance Analysis • To guarantee || > ||： > - (4) • Combining (3) and (4) >(5) then, = , for (6) (7)

14. Experimental Results-setup • Implemented by using Java and C/C++. • H.264/AVC JM Software is used as a video codec. • Test video sequences：Harbour and Soccer of CIF size and 15 fps. • The GOP structure is set to include one I-frame and 29 P-frames. • Every simulation is repeated 1000 times and averaging values of the repeated simulations • LT codes：robust soliton distribution and two parameters of this degree probability distribution are set to 0.03 and 0.5, respectively

15. Performance Verification of the Proposed PacketizationAlgorithm

16. Performance Verification of the Proposed Packetization Algorithm

17. Performance Verification of the Proposed Packetization Algorithm

18. Performance Verification of the Proposed Packetization Algorithm

19. Video Quality Comparison When Packet Loss Pattern Is Random

20. Video Quality Comparison When Packet Loss Pattern Is Random

21. Video Quality Comparison When Packet Loss Pattern Is Random

22. Video Quality Comparison When Packet Loss Pattern Is Burst

23. Video Quality Comparison When Packet Loss Pattern Is Burst

24. Video Quality Comparison When Packet Loss Pattern Is Burst

25. Video Quality Comparison When Packet Loss Pattern Is Burst

26. Video Quality Comparison When Packet Loss Pattern Is Burst

27. Conclusion • An efficient LT encoding pattern-aware packetization algorithm for LT encoded symbols to provide a robust video streaming service over error-prone wireless network. • The basic concept of the proposed packetization algorithm may be extended to other fountain codes with some modifications.