Real-time content analysis and adaptive transmission of lecture videos for mobile applications

Abstract

With the popularity of e-learning systems, there is an increasing demand on effectively utilizing instructional videos to augment distance learning experiences. This paper addresses some special issues in processing and streaming lecture videos, and provides a new approach for real-time content analysis and adaptive transmission of these videos over wireless networks. A content-based analysis method and a buffer-based model are provided to detect content regions and to select content significant key frames, and an adaptive feedback control scheme is applied to transmit properly compressed key frames to accommodate dynamically changing bandwidths in wireless environments, with consideration of the limitations of resolution and computing capability of mobile devices. We demonstrate the effectiveness and scalability of our system in experimental results of adaptive transmission of instructional videos over 802.11b wireless networks to mobile devices.