Study On Region-Of-Interest Image Coding In JPEG2000 Standard

Region-Of-Interest (ROI) image coding is a new feature in the newly published JPEG2000 still image compression standard, which allows ROIs to be coded with better quality than the rest of an image, i.e., background. This paper focuses on ROI image coding methods and their application in the JPEG2000 still image compression standard. The main work can be summarized as follows:1. The general information of the JPEG2000 still image compression standard is introduced, and each part of the JPEG2000 coder is discussed in detail according to the JPEG2000 encoding order.2. The Region-Of-Interest image coding and Foveal Processing theory are discussed. Some of their applications are also introduced.3. A so called Active Shift ROI coding method is proposed. By actively removing part of the high frequency wavelet coefficients, the method can make an acceptable image compression result for both coder and decoder.4. An ROI coding method realized by foveation technology and two of its extended applications are presented. By unevenly upscaling the wavelet coefficients, the method can not only reconstruct the ROI data priorly in a low bit-rate codestream, but make the progressive reconstruction of the image data more convenient for the human vision system.