Koji Imura

Error resilient video coding schemes for real-time and low-bitrate mobile communications

In this paper, we present self error resilient video coding schemes for low-bitrate mobile communication. They are the dual forward prediction and the adaptive refreshing. If a coded bit stream suffers from transmission error, the reconstructed image is degraded and the degradation is propagated temporally. The dual forward prediction minimizes the degradation by using two prediction images selectively. Also, the adaptive refreshing quickly eliminates the degradation by concentrating the cyclic intra refreshing on the moving area of image. The simulations are conducted on MPEG-4 test sequences at 24 k and 48 kbps. Experiment results show that the dual forward prediction is effective for the bursty error and it improves the coding efficiency for some sequences. Concerning the adaptive refreshing, it is shown that both PSNR and subjective quality are improved. In conclusion, the proposed schemes are highly error resilient and suitable for low-bitrate mobile communication.