電機工程學系 ; In this paper, a novel error-resilient coding technique, named multiple description scalar quantization for fine granularity scalability (MDSQ-FGS), is presented to enhance error resilience capability and to improve the temporal prediction efficiency for video coding over lossy packet networks and wireless channels. MDSQ-FGS video coding scheme based on multiple descriptions coding (MDC) with modified multiple description scalar quantization (MDSQ) and partial predictions are proposed to control drifting error without too much reduction in efficiency. We also combine the benefits of multiple stream coding and multiple path transmission to maintain best constant video quality despite packet loss when roaming in wireless LANs (WLANs). Simulation results indicate that the proposed coding system outperforms the normal MPEG-4 FGS coder for coding efficiency, and can significantly improve the quality of streamed video when mobile client roams in WLAN.