An improved algorithm to apply ROI coding in low bit rate image compression

Most significant bit-plane shift is an available method in low bit rate compression,but it changes the structure of high and low frequency of ROI so there is distortion in ROI,to avoid it an improved algorithm called according to resolution most significant bit-plane shift(ARMSBShift) is proposed in this paper.This algorithm can improve the qualities both of ROI and background than the old method.At bit-rate 0.8bpp the new algorithm increased the peak signal-to-noise(PSNR) of the ROI by 1.34dB and the background by 0.72dB at best.