Progressive image transmission with RCPT protection

In this paper, a joint source-channel coding scheme is proposed for progressive image transmission over channels with both random bit errors and packet loss by using rate-compatible punctured Turbo codes (RCPT) protection only. Two technical components which are different from existing methods are presented. First, a data frame is divided into multiple CRC blocks before being coded by a turbo code. This is to secure a high turbo coding gain which is proportional to the data frame size. In the mean time, the beginning blocks in a frame may still be usable although the decoding of the entire frame fails. Second, instead of employing product codes, we only use RCPT, along with an interleaver, to protect images over channels with combined distortion including random errors and packet loss. With this setting, the effect of packet loss is equivalent to randomly puncturing turbo codes. As a result, the optimal allocation of channel code rates is required for the random errors only, which largely reduces the complexity of the optimization process. The effectiveness of the proposed schemes is demonstrated with extensive simulation results.