英文摘要 |
Scalable video coding techniques, such as multiple description coding (MDC), not only effectively address the issue of delivering videos over error-prone networks but also provides solutions of servicing scalable videos for heterogeneous clients. When multiple description coded video chunks are received at a client, they must be buffered based on network condition and also be timely decoded and merged in order to provide smooth playback. In this paper, we present the design and implementation of a novel H.264 player for multiple description coded videos. There are two major buffers in our MDC player, which are decoded chunks buffer and merged chunks buffer. To avoid buffer overflow or underflow, merging control and transmitting rate control mechanisms are proposed. Experiment results show that with the aids of proposed control mechanisms, no buffer overflow or underflow was experienced during the playback. Most importantly, based on our measurement, the overheads of decoding a chunk and merging chunks are negligible compared to rendering time of one chunk, which would not affect the smoothness of playback at all. |