A REAL-TIME ADAPTIVE IMAGE DATA COMPRESSION SYSTEM BY RIDPCM

摘要

In this paper a two-dimensional block coding system by RIDPCM (recursive interpolation differential pulse code modulation)is reported.This system executes real-time adaptive coding for image data.Maximum of absolute values of difference data and sum of absolute values of difference data are used as classification criteria.The system equips four kinds of bit assignment.Singal quantizer is used.Classification threshold can be obtained easily.Buantization accuracy of ali image blocks is same.Adaptive coding process is very simple since only comparasion calculation is needed during the classification.Coding time is saved because classification and coding are completed simultaneously.The number of IC chips used in the system is 240,system is small in volume and light in weight,the Highest coding data rate is 7.6 Mbits/s under the limitation of TTL and low speed MOS elements.When image "girl" is coded by this system MSE (mean square error) is 0.000628 with coding bit rate of 0.670 BPP (bits per pixel).