Unequal Error Protection for Proxy-based Handheld Device Access to Live NASA Satellite Weather Images

摘要

We present a hybrid unequal protection scheme to a system for mobile wireless broadcasting of the Low Resolution Picture Taking (LRPT) weather image data. The image data is compressed by SPIHT source coder. The original bit stream of SPIHT is first demultiplexed into two substreams as location bit class (LBC) and value bit class (VBC) with different error resilience properties. The channel protection level to different bit planes of LBC is designed empirically based on the analysis of their error sensitivity. An end-to-end distortion (R-D) function of VBC is proposed. The threshold of SPIHT and channel protection levels to different bit planes of VBC is optimized based on the R-D function under the fixed remaining bit rate. Experimental results show the proposed scheme outperforms some of the state-of-the-art systems.