Content-aware rate adaptation scheme to improve stability in HTTP Adaptive Streaming
Myongwoo Kim, Jiwoo Park, Kwangsue Chung · 2017
HTTP-based adaptive streaming (HAS) has recently been widely deployed on the Internet. In the HAS approach, a video content is encoded at multiple bitrates and the encoded video content is segmented into small parts of fixed durations. The HAS client requests a video segment, and stores it in the playout buffer. Many studies have shown a robust rate adaptation algorithm is critical to ensuring quality-of-experience in HAS systems. However, most existing algorithms use a poorly designed bandwidth estimation method to adjust video bitrates. In this paper, we propose a novel content-aware rate adaptation algorithm that improves stability of the HAS system. In our method, the playout buffer is modeled with content characteristics. Different from previous works, we propose to adapt video bitrates based on the variance in playout buffer length, rather than static buffer information. We evaluate the performance of the proposed algorithm by simulation and subjective tests. Through extensive simulations, we demonstrate that the proposed scheme achieves very high quality smoothness, even under variations of network bandwidth.