1. Error Concealment For Fine Granularity Scalable Video Transmission Hua Cai; Guobin Shen; Feng Wu; Shipeng Li; Bing Zeng; Multimedia and Expo, 2002. Proceedings. 2002 IEEE International Conference on

2. Outline Introduction Temporal and Spatial Correlations Proposed Error Concealment Method Interleaving MBS Experimental Result Conclusion

3. Introduction Bandwidth fluctuation  Network heterogeneity  Competitions among traffic  Fine Granularity scalability (FGS) coding scheme Transmission Error  Error Resilience FEC, Data partition, Resynchronization mark  Error Concealment (EC)

4. Introduction (cont.) Error Concealment  To be implemented at the decoder side  Enhancement layer packets Contaminated regions

5. FGS encoded bitstream Two Bitstream  Base layer and Enhance layer Bits B (f) = E 。 Q B {DCT[O(f) – MC(R B (f-1))]} Bits E (f) = E 。 Q E {DCT[O(f) – R B (f)]}

6. Temporal Correlation Temporal correlation exists in the FGS bitstream R B (f)  R B (f-1) + DCT -1 {Q[Enh(f-1)]} if O(f) = O(f-1) O(f) = R B (f-1) + DCT -1 [Enh(f-1)] if O(f) = O(f-1)

7. Proposed Error Concealment Method Temporal correlation could be used to improve the quality of contaminated regions  is the interpolation ratio within the region [0,1] It reflect the intensity of the temporal correlation  Intra coded block,  approaches 1

8. Optimal Interpolation Ratio  0 For each 8x8 block, the optimal interpolation ratio  0 can be found by minimize the distortion between the origin and the interpolated one.

9. Optimal Interpolation Ratio  0 (cont.)

10. Spatial Correlation It is impossible to find  at the decoder side The spatial correlation could be used for predicting the contaminated regions’ temporal correlation 11 22 33 44 55 x1x1 x2x2 66 77 x3x3 x4x4 88 99  10  11  12

11. Spatial Correlation (cont.)

12. Interleaving MBS during Packetization 3055295428532752265125 7999789877977696759574 2450234922482147204619 7394729371927091699068 1845174416431542144113 6789668865876486638562 1240113910389378367 6184608359825881578056 6355344333322311 The Packetizing order for QCIF sequence

13. Experimental Result

14. Experimental Result (cont.)

15. Conclusion This paper presents an efficient EC method for FGS video transmission. Temporal redundancy is used to improve the quality of the contaminated regions. The intensity of the temporal correlation is estimated exploiting the spatial correlation in the surrounding high-quality regions.