Performance of a Source/Channel Encoded Imagery Transmission System

摘要

The performance of an image transmission system which combines an image source encoding technique with communication channel codes is theoretically calculated and measured by simulation. The theoretical and simulated results show that replacing source data bits with error correction coding bits can reduce the distortion in the received image. The magnitude of the reduction depends on the transmission rate, the code rate (N/K) of the channel code, the procedures used to apply the channel code and the error rate of the communication channel. The image source encoding technique used is the two dimensional Discrete Cosine Transform. This technique is combined with both block and convolutional channel codes to form the source/channel encoded imagery transmission system. The distortion in the received image is measured using a weighted mean square error criterion in which the weighting is related to the frequency sensitivity characteristics of the human visual system. (Author)