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Buffer-Based Adaptive Bitrate Algorithm for Streaming over HTTP
( Waqas Ur Rahman ),( Kwangsue Chung ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.11
Video streaming services make up a large proportion of Internet traffic on both fixed and mobile access throughout the world. Adaptive streaming allows for dynamical adaptation of the bitrate with varying network conditions, to guarantee the best user experience. Adaptive bitrate algorithms face a significant challenge in correctly estimating the throughput as it varies widely over time. In this paper, we first evaluate the throughput estimation techniques and show that the method that we have used offers stable response to throughput fluctuations while maintaining a stable playback buffer. Then, we propose an adaptive bitrate scheme that intelligently selects the video bitrates based on the estimated throughput and buffer occupancy. We show that the proposed scheme improves viewing experience by achieving a high video rate without taking unnecessary risks and by minimizing the frequency of changes in the video quality. Furthermore, we show that it offers a stable response to short-term fluctuations and responds swiftly to large fluctuations. We evaluate our algorithm for both constant bitrate (CBR) and variable bitrate (VBR) video content by taking into account the segment sizes and show that it significantly improves the quality of video streaming.
A novel adaptive logic for dynamic adaptive streaming over HTTP
Rahman, Waqas ur,Chung, Kwangsue Elsevier 2017 Journal of visual communication and image represen Vol.49 No.-
<P><B>Abstract</B></P> <P>In this paper, we propose an estimation method that estimates the throughput of upcoming video segments based on variations in the network throughput observed during the download of previous video segments. Then, we propose a rate-adaptive algorithm for Hypertext Transfer Protocol (HTTP) streaming. The proposed algorithm selects the quality of the video based on the estimated throughput and playback buffer occupancy. The proposed method selects high-quality video segments, while minimizing video quality changes and the risk of playback interruption, improving user’s experience. We evaluate the algorithm for single- and multi-user environments and demonstrate that it performs remarkably well under varying network conditions. Furthermore, we determine that it efficiently utilizes network resources to achieve a high video rate; competing HTTP clients achieve equitable video rates. We also confirm that variations in the playback buffer size and segment duration do not affect the performance of the proposed algorithm.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Throughput estimation method based on the throughput observed over past segments. </LI> <LI> Rate adaptive algorithm based on the buffer occupancy and estimated throughput. </LI> <LI> Selects high-quality video segments, while minimizing video quality changes. </LI> <LI> Minimizes the risk of playback interruption. </LI> <LI> Competing HTTP clients achieve equitable video rates. </LI> </UL> </P>