A study of error robustness evaluation for H.264 video coding system
| Autor: | Chi-wei Tung, 董棋偉 |
|---|---|
| Rok vydání: | 2006 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 94 In this thesis, we study the robustness of the recently ratified video compression standard H.264/AVC against channel errors. We first analysis the abilities of error resilience for the parameters in the video coding layer (VCL) including the header information, prediction modes, motion vectors and intra data over error-prone channels. Single bit and burst errors are likely to propagate through the bit stream, and then cause the error propagation to many subsequently decoded pictures. Because errors remain visible for much longer than a single picture display period, the resulting artifacts are particularly annoying to viewer. Therefore, we develop an approach toward joint source-channel coding for H.264/AVC system. In many cases, the errors of transmission channels can be efficiently corrected by classic channel coding methods such that forward error correction (FEC) and automatic repeat request (ARQ) or a mixture of them. However, this is achieved at the cost of reduced throughput and increased delay. In order to overcome the problem, we utilize universal rate distortion characteristics which are obtained experimentally and show the sensitivity of the source encoder and channel encoder to channel errors. We employ the rate allocation of source encoder and channel encoder by the Lagrangian multiplier. Further, we can use the results of this rate allocation algorithm for video transmission over an error prone-channel using H.264/AVC for source coding and rate-compatible punctured convolutional codes (RCPC) for channel coding. The proposed scheme is tested for the transmission of video over noise channel. Experimental results clearly demonstrate the superior robustness of the proposed joint source-channel coding in comparison with the default scheme for H.264/AVC system. Moreover, simulation results also show that the proposed H.264/AVC scheme provide acceptable image quality even in high bit error rate environments. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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