A Video Communication System Based on Spatial Rewriting and ROI Rewriting

Scalable Video Coding (SVC), as an extension of H.264/AVC, has been designed to provide H.264/AVC compatible base layer and spatial, temporal and quality enhancement layers. Bit-stream rewriting in SVC standard makes it possible to convert a quality enhancement layer to a H.264/AVC bit- stream. So that H.264/AVC decoder users could also experience high quality video content when network condition and hardware permits. In this paper, we present a scalable video rewriting system which is featured by the ability to rewrite spatial enhancement layers and range-of-interest (ROI) of enhancement layers. Compared to traditional rewriting, the proposed system is suitable for more application scenarios and is more flexible.