A DPCM system with modulo limiters

The authors introduce a DPCM (differential pulse code modulation) system with modulo limiting (DPCM-ML). The ML in the DPCM system compresses the dynamic range of the prediction error by 6 dB. Therefore, fewer quantization levels are required to maintain the same level of quantization noise as in DPCM without ML. The reduced number of quantization levels translates to more efficient encoding and therefore lower data rate. The DPCM-ML system has a built-in self-correcting mechanism in which the ML at the receiver automatically tracks and corrects the DC offset applied to the prediction error by the ML at the transmitter. Experimental and simulation results on an interframe DPCM-ML for image sequence coding are presented.<>