Video transcoding for wireless gateway system

In this paper we study the problem of accessing video streams through handheld devices and wireless networks. We first review and discuss the major technologies of video transcoding. Then, we introduce a wireless video transcoding gateway system to handle the heterogeneous mobile devices and the smallness capability of the handheld devices. To gain higher video quality and lower complexity, we propose an efficient video transcoding structure based on close-loop model and a fast motion vector re-estimation algorithm. Based on this, we design a novel service scheme, which can provide better video content access service on current mobile communication systems. Moreover, we implement a test prototype of MPEG2-to-H264 transcoding system and simulate the video streams access service in a wireless LAN.