A hybrid image coder: adaptive intra-interframe prediction using motion compensation

A hybrid image predictive coding method is presented. The intraframe predictor is an adaptive FIR (finite impulse response) filter that uses the LMS (least mean squares) algorithm to track spatial local characteristics of the intensity continuously. The interframe predictor is motion-adaptive, using a pel-recursive method to estimate the displacement vector. A weight coefficient is adapted continuously in order to favor the prediction mode that performs better. For the sequence examined a significant improvement is obtained in comparison with either mode alone. A crucial problem in predictive coding, particularly with adaptive techniques, is that of sensitivity to transmission errors. A method ensuring the autoadjustment of the decoder in the presence of isolated transmission errors is proposed for the intraframe mode. Neither overhead information nor an error-correcting code are needed