自动化学报
自動化學報
자동화학보
ACTA AUTOMATICA SINICA
2008年
3期
337-343
,共7页
张源海%李凯慧%许长桥%孙利民
張源海%李凱慧%許長橋%孫利民
장원해%리개혜%허장교%손이민
Variable-bit-rate (VBR)%video streaming%program clock reference (PCR)%buffer management%proportional-integra controller
In this paper we present an adaptive video transmission framework that integrates rate allocation and buffer control at the source with the playback adjustment mechanism at the receiver. A transmission rate is determined by a rate allocation algorithm which uses the program clock reference (PCR) embedded in the video streams to regulate the transmission rate in a refined way.The server side also maintains multiple buffers for packets of different importance levels to trade off random loss for controlled loss according to the source buffer size, the visual impact, and the playback deadline. An over-boundary playback adjustment mechanismbased on proportional-integra (PI) controller is adopted at the receiver to maximize the visual quality of the displayed video according to the overall loss and the receiver buffer occupancy. The performance of our proposed framework is evaluated in terms of peak signal-to-noise ratio (PSNR) in the simulations, and the simulation results demonstrate the improvement of the average PSNR values as well as the better quality of the decoded frames.