1. Minimum Cost Scheduling of Stored Video in Dynamic Bandwidth Allocation Networks Reporter ： M9756003 張益瑞 IEEE Transactions on Consumer Electronics, Vol. 53, No. 2, MAY 2007 Myeong-jin Lee, Member, IEEE 2016/3/81

2. Outline Introduction Service Cost Minimization Framework for Stored Video Transmission Problems in Conventional Optimal Video Streaming Algorithms Proposed Algorithm for Minimum Cost Scheduling Experimental Results Conclusion 2016/3/82

3. Introduction Most current and future video applications will require the playback of stored video over a high- speed network. Dynamic bandwidth allocation methods. Renegotiated constant bit-rate (RCBR) 2016/3/83

4. Service Cost Minimization Framework for Stored Video Transmission Dynamic Bandwidth Allocation for Video Streaming Cost for RCBR Service of Stored Video 2016/3/84

5. Dynamic Bandwidth Allocation for Video Streaming Compressed video sources show burstiness over multiple time-scales, periods of milliseconds to several seconds. RCBR has the key advantage that the signaling cost and the network function for renegotiations are as simple as those of the constant bit-rate (CBR) service. 2016/3/85

6. Cost for RCBR Service of Stored Video S=segment R=transmission rate L=segment length C=cost S*=scheduled result α=bandwidth cost parameter β= renegotiation cost parameter N=the number of transmission segments in S* 2016/3/86

7. Problems in Conventional Optimal Video Streaming Algorithms Cost Functions for Transmission Segments The Need for Minimum Cost Scheduling for Video Streaming 2016/3/87

8. Cost Functions for Transmission Segments The transmission cost of a single isolated segment α=bandwidth cost parameter β= renegotiation cost parameter the transmission cost of a group of successive segments from S k to S k+n can be represented as follows. 2016/3/88

9. Cost Functions for Transmission Segments To show the effect of short transmission segments on the cost, the cumulative cost ratio is defined as follows. This represents the ratio of the transmission cost for short segments to the overall cost for the whole video sequence. 2016/3/89

10. The Need for Minimum Cost Scheduling for Video Streaming Cumulative number of renegotiations for video streaming under RCBR service. 2016/3/810

11. The Need for Minimum Cost Scheduling for Video Streaming Service cost for stored video under RCBR service 2016/3/811

12. Proposed Algorithm for Minimum Cost Scheduling Segment Merging as a Tool for Cost Minimization Relative Cost Flags for Segment Merging Proposed Minimum Cost Scheduling Algorithm 2016/3/812

13. Segment Merging as a Tool for Cost Minimization We define ⊕ as the segment merging operator, the new segment after merging successive segments is represented by the algorithm. The new transmission rate should be the maximum between those two segments in order to satisfy the decoder buffer underflow constraint. 2016/3/813

14. Relative Cost Flags for Segment Merging To determine the segment merging, relative cost flags are defined for each segment. They are calculated using (7) and (8). 2016/3/814

15. Relative Cost Flags for Segment Merging Merging of neighboring segments for minimum cost scheduling based on relative cost flags There are three possible combinations of the left-hand and the right-hand relative cost flags. 2016/3/815

16. Relative Cost Flags for Segment Merging Merging of neighboring segments for minimum cost scheduling based on relative cost flags There are three cases of segment merging. 1.Not merged 2.merged into the left-hand segment. 3.merged into the right-hand segment. 2016/3/816

17. Proposed Minimum Cost Scheduling Algorithm Video traffic smoothing algorithm for the minimum service cost 2016/3/817

18. Experimental Results Mpeg video 40,000frame GOP pattern is IBBPBBPBBPBB We assumed that renegotiation requests are always accepted by networks. 2016/3/818

19. Experimental Results Service cost reduction during execution of the proposed minimum cost scheduling algorithm. 2016/3/819

20. Experimental Results Scheduled results of the proposed algorithm. Bond sequence 2016/3/820

21. Experimental Results Overall service cost of the proposed algorithm. Bond and news sequence. 2016/3/821

22. Experimental Results Overall service cost of the proposed algorithm. Bond and news sequence. 2016/3/822

23. Experimental Results Overall service cost of the proposed algorithm. Bond and news sequence. 2016/3/823

24. Experimental Results Characteristics of the scheduled traffic. Bond and news sequence. 2016/3/824

25. Experimental Results Characteristics of the scheduled traffic. Bond and news sequence. 2016/3/825

26. Experimental Results Characteristics of the scheduled traffic. Bond and news sequence. 2016/3/826

27. Conclusion A minimum cost scheduling algorithm is proposed for high-quality video streaming in dynamic bandwidth allocation networks. The proposed algorithm can be easily extended to other service environments with different service pricing models. 2016/3/827