Improved digital image transmission with turbo product codes

Digital image transmission without channel coding and with turbo product codes (TPCs) as channel coding scheme over AWGN channel is studied. We propose an improved decoding algorithm for TPCs based on computing extrinsic information for partial bits. In the proposed decoding algorithm, we neglect computing extrinsic information for those bits that are reliable enough for making decoding decisions. Simulation results indicate that the proposed algorithm can reduce the computational complexity and improve the decoding speed without performance degradation. In addition, we apply TPCs to digital image transmission system and study the effect of the reconstructed images. The results show that the TPCs have powerful error correction capability while greatly saving the system transmission power, which is an evidence of TPCs being suitable for digital image transmission.