Imprecise computation scheduling on scalable media stream delivery

Scalable media streaming provides a layered representation for transmitting media contents over the Internet with packet loss and variable delay. It is an important problem about how to select and schedule packet delivery of a scalable streaming media server. In this paper, we propose a real-time scheduling algorithm based on imprecise computation model for real-time scalable media streams. The scheduling task of a scalable media stream is partitioned into two sub tasks: the mandatory subtask and the optional subtask. The mandatory subtask is for the substream of base layer and the optional subtask is for the substreams of enhancement layers. The imprecise computer model and scheduling algorithm provide scheduling flexibility by trading off video quality reconstructed in client to meet playback deadline. Thus, the better usage of available bandwidth and the smoother playback are achieved. Simulated results show that, with the proposed approach, the playback quality has an obvious improvement.