【摘要】 提出了一个基于MPEG 4精细可分级编码技术的视频流式传输系统。介绍了系统中主要模块的作用,并重点研究了速率控制模块。速率控制模块采用了适合视频流式传输的动态带宽分配方法。它可以根据实时的网络通道波动状况来动态调整滑动参数,以适应网络波动和高效地利用网络的有限资源。实验结果表明,动态带宽分配方法在动态带宽波动条件下不仅可以使相邻帧间的视频质量更加平滑,而且可以大大提高解码视频图像的总体质量,也就是说可同时改善解码视频的主客观性能。更多还原

【Abstract】 A video streaming system based on MPEG4 fine granularity scalability (FGS) is presented. Main modules are introduced, and rate control module is heavily analyzed. The rate control module adopts a dynamical bandwidth allocation method for video streaming, which can scale dynamically sliding parameter according to network variation condition in order to adapt to network variation and to utilize network resource with high efficiency. Experimental results show that under dynamic bandwidth conditions, the proposed method not only can make quality fluctuations between adjacent frames much smoother, but also can improve average peak signal to noise ratio (PSNR) of the whole video sequence greatly,it’s to say, the proposed method can improve subjective and objective visual quality at the same time.更多还原