The performance of video transmission over wireless channels is limited by the channel noise. Thus many error resilience tools have been incorporated into the MPEG-4 video compression method. In addition to these tools, the unequal error protection (UEP) technique has been proposed to protect the different parts in an MPEG-4 video packet with different channel coding rates based on the rate compatible punctured convolutional (RCPC) codes. However, it is still not powerful enough for the noisy channels. To provide more robust MPEG-4 video transmission, this paper proposes a modified unequal error protection technique based on the mutual information of two video frames. In the proposed technique, the dynamic channel coder rates are determined online based on the mutual information of two consecutive video frames. With this technique, irregular and high motion areas that are more sensitive to errors can get more protection. Simulation results show that the proposed technique enhances both subjective visual quality and average peak signal to noise ratio (PSNR) about 2.5 dB, comparing to the traditional UEP method.

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