Predictive ordering and linear approximation for image data compression

A method of efficient image coding called predictive ordering and linear approximation (POLA) is presented. By taking as reference the previously-received scan line, the pixels of the present scan line are placed in order of decreasing amplitudes. The regression line of the ordered pixels is estimated. The linear approximation is refined by computing the one-bit error pattern and by preserving the first two sample moments of the scan line. Simulation results are given showing good image quality at a low bit rate of about 1 bit/pixel