A new region-of-interest image compression method based on Wyner-Ziv coding

The JPEG2000 image coding standard defines two kinds of region of interest (ROI) compression methods--the general scaling based method and the maximum shift (maxshift) method. There are two major drawbacks of the two methods. First, they would significantly reduce the compression efficiency by increasing the dynamic range (or number of bitplanes) of wavelet coefficients. Second, they do not have the especial protection for the ROI against the bit errors in image communication application, i.e., remote medical treatment and Satellite Communication. When the bit errors occurred, the reconstruction quality of ROI and BG would reduce at the same time. In this paper, a new and flexible ROI image compression method is proposed according to the Wyner-Ziv theorem on source coding with side information. The reconstructed low quality ROI is regard as a noisy version of original ROI in the proposed method. So, along with the parity bits from the original ROI, the reconstructed low quality ROI as side information can be utilized to Turbo decoder to decode the high quality ROL Our experimental results show that the proposed method applying the Wyner-Ziv coding to ROI compression can highly improve the compression efficiency as well as efficiently protect the ROI against the bit errors.