Low-latency dynamic adaptive video streaming

Abstract

Accurate, dynamic rate selection is considered a hard problem in stream switching video applications over Internet Protocol. Not only the feedback delay but also the unawareness about the dynamics of the underlying HTTP/TCP transport layer require streaming applications to implement huge receiver buffers in the order of tens of seconds so as to maintain continuous video rendering with acceptable quality and bandwidth utilization. In order to achieve low-latency adaptive video streaming with a buffering delay as low as the chunk size, we present a streaming architecture under the implementation of media transport with predictably reliable transport and delay-based congestion control. A key component of our solution is a server-side simulation of the streaming client's buffer, which provides low-delay feedback for the video rate selection. The receiver buffer is being controlled via an open-loop synchronization mechanism relying on a reference clock that is transmitted within the media packets. We demonstrate the performance of our approach by evaluating the stability of the receiver buffer under low-latency and highdefinition adaptive video streaming with variable bit rate encoding over an emulated wide area network link.