Low Power Video Streaming for PDAs

摘要

In this paper, we propose an battery-aware video streaming system which can extend battery life of portable computing devices to a desired playback duration in streaming video playback. The proposed system transcodes a video stream from the content server to the lightweight stream to save power consumption. Our system includes another power saving mechanism where video data is received and stored in a buffer on the portable device at the maximum transmission speed, and the wireless NIC is powered off until the buffer becomes empty. We define a power consumption model on the portable device to determine several video parameters satisfying a user requirement. We have implemented the system and carried out several experiments. As a result, we have confirmed that our system can extend the battery life up to 2.5 times and that the predicted battery life can be estimated accuratery using our model.