Region-of-interest coding based on set partitioning in hierarchical trees

In many image coding applications, such as Web browsing, image database and telemedicine, it is useful to reconstruct only a region of interest (ROI) before the rest of the image is reconstructed. An ROI coding functionality is incorporated with the set partitioning in hierarchical trees (SPIHT) algorithm (see Said and Pearlman, IEEE Trans. Circuits and Systems for Video Technology, vol.6, p.243-50, 1996). By emphasizing the ROI coefficients, they are coded with higher fidelity than the rest of the image in early stages of progressive reconstruction. The main thrust of this research is how to identify necessary coefficients for the decoder to reconstruct the desired region. The proposed method provides better performance than the previous method