Zone coding of DCT coefficients for very low bit-rate video coding

A method for decreasing the output bit-rate of video transmission over limited bandwidth in communication networks is proposed in this paper. To increase the efficiency of video transmission, the method based on a concept of zone coding of discrete cosine transform (DCT) coefficients is used in video coding scheme to achieve a lower output bit-rate of encoded video. The experiments are carried out by implementing the proposed method with a low bit-rate video coding standard i.e. H.263. The performance of the coding scheme is measured in term of peak signal to noise ratio (PSNR), output bit-rate and quality of the decoded video sequence. The experimental results show significant improvements in term of output bit-rate. Although the quality of resultant image frames is slightly degraded, it is difficult to notice by the human visual system (HVS), and hence considered being in an acceptable level.