VAAL, Video Adaptation at Application Layer and Experiments using DCCP

Abstract

International audienceMore and more high definition and high quality videos are nowadays stored on Internet but they are not accessible for everybody because high and stable bandwidth is needed to stream them. A lower bitrate encoding is usually chosen but it leads to lower quality too. A solution is to use a TCP-friendly transport protocol and let the application itself choose for each user the bitrate of the video which matches the network bandwidth. This paper presents VAAL, a simple and efficient method designed to ameliorate user video experience. It involves only the application layer on the sender. The main idea of VAAL is that the sender application monitors the network conditions by checking transport protocol buffer overflows and adapts the video bitrate accordingly. Experimental results show that the video adaptation using VAAL performs very well compared to the currently widely-used static encoding