Mobile image transmission using combined source and channel coding with low complexity concealment

Abstract

In this paper, we propose an efficient image transmission system for reliable transmission of vulnerable compressed images over mobile radio channels. The image coder is fully compatible with the JPEG baseline coding standard. Its transmission system is designed based on lossy transmission with combined source and channel coding (CSCC) and low complexity error concealment. Specifically, the proposed CSCC uses block codes which are designed to match both the coded image characteristics and wireless channel statistics, thereby accomplishing efficient transmission along with good visual quality. Together with a block-shuffling scheme, a simple error-concealment technique is introduced to effectively reconstruct the damaged image blocks caused by the residual errors. It is shown that the proposed techniques are applicable to mobile image transmission with different compression ratios under various mobile channel conditions. Performance results based on images `LENA' and `AIRPLANE', which are coded at 0.85 and 0.90 bit/pixel, respectively, under the simulated GSM channel (Pan-European Cellular Standard) with an average SNR (signal-to-noise ratio) of 18 dB and various vehicle speeds (2–50 miles/h) indicate that the proposed system achieves a throughput as high as 70% with good visual quality at PSNRs (peak signal-to-noise ratio) around 30 dB for the reconstructed images.