針對H.264/SVC使用SCTP之可靠影音傳輸演算法

Abstract

近年來，在網路上收看各式各樣的電視節目及影片是一件相當普遍的行為。 為了要配合異質終端的能力和網路壅塞程度提供不同種解析度的影片，可適性視訊編碼(scalable video coding)使視訊傳輸更能適應在異質的網路環境。為了使影片的播放能更為流暢，避免在撥放途中發生影片中斷，在此篇論文中，我們對可視訊編碼提出一個的資源排程演算法。此演算法基於串流控制傳輸協議(Stream Control Transport Protocol, SCTP)在網路上傳輸可適性視訊編碼串流，並且透過一個機率模型估算對於重要的資訊至少要預留多少重傳的次數才能確保整體影片有一定程度的可靠性，藉此犧牲些微影片解析度換取影片的流暢度。在實驗的部分，我們將提出的演算法透過SCTP傳輸並與被廣泛使用的RTP/UDP方法和基本的SCTP做比較。可由結果看出，與基本的SCTP作比較，我們點算法將能夠被撥放影片的比例提升20%，畫質部分也提升13.5%。

In recent years, it is prevalent for people to watch television shows and videos on internet. Scalable Video Coding (SVC) comes as a solution that adapts to network congestion and terminals heterogeneity. In this paper, we proposed an adaptive resource scheduling algorithm to send SVC-based videos over Stream Control Transport Protocol (SCTP) in order to play the video smoothly without interruption. We developed a probabilistic model to estimate how much bandwidth should be preserved. The preserved bandwidth is used to retransmit the important information for a reliable video transmission. On the other hand, our approach can mitigate the reduction of video resolution when some bandwidth was reserved. Our transmission scheme is compared with the widely used RTP/UDP method and standard SCTP. Simulation results show that our algorithm has 20% improvement on decodable frame rate and 13.5% improvement on the video quality compared with the standard SCTP.