WiVision: a wireless video system for real-time distribution and on-demand playback

The ability to deliver digital video over wireless networks is an enabling technology for many useful applications, ranging from home entertainment and security monitoring to enterprise messaging and military reconnaissance, and thus represents the holy grail of wireless technology development. We describe a wireless video delivery system, WiVision, which uses IEEE 802.11 wireless LANs as the last mile for both real-time video distribution and on-demand video playback. WiVision can air both live events, such as on-campus seminars and sports activities, and prestored video streams, such as course lectures and financial analysis sessions, to mobile users, who can tune in to selected channels of their choice from their laptops or PDAs. An innovative feature of WiVision is the support for random video access based on keyword-search, where keywords are extracted from the closed-caption text embedded in TV programs. In addition, WiVision is able to broadcast video streams on the wireless link while seamlessly working with commercially available media players. The paper presents the implementation details of the real-time acquisition and network transport components of a fully operational WiVision prototype, and the results of a performance evaluation study on that prototype.