Distributed Video Transcoding for Live and Interactive Multimedia Applications

Abstract

One of the major challenges of video service providers is offering high Quality of Experience (QoE). Satisfying high QoE is a challenging problem given the diversity in end-device characteristics and network conditions as well as the increased popularity of live and interactive streaming applications. For a user to have acceptable QoE, the streaming services need to adapt video quality to device specifications and network quality at runtime. Runtime adaptation, i.e., transcoding, is a challenging problem due to the computationally intensive nature of the transcoding process. In particular, novel techniques are needed for maintaining the real-time property of a video stream in spite of this high computational demand. This thesis proposes Stride and Contrast, two different distributed transcoding approaches that address this challenge. We outline the design and performance optimization of these approaches. Results show that our approaches outperform other similar techniques used in practice and proposed by other researchers.