A Syntax Aware Error-Tolerant Encryption for Secure Multimedia Communications

Over the last few decades, a variety of multimedia services have become increasingly popular among various business and personal users. The security of multimedia is an important and challenging issue due to the large data volume of multimedia video and audio. The traditional data encryption framework, which encrypts the entire multimedia files, is not only slow, but also unable to tolerant any uncorrectable channel errors. This problem is especially severe for wireless communications that is more prone to multipath distortion and fading. Generally, if errors remain after error decoding of a received data packet, a request for retransmission is sent back to the transmitter. The retransmission could significantly reduce the system throughput when the channel is lousy since many retransmissions could be possible though the errors that remain could be very small. To solve this problem, in this paper we propose a syntax aware encryption framework for selective error-tolerant encryption. The proposed scheme can be applied to applied in both time domain and frequency domain alike to significantly improve network throughput, while quality degradation of the multimedia video and audio can barely be a problem for human eyes and ears even for extremely bad communication channels.