Exploitation and extension of the region-of-interest coding functionalities in JPEG2000

The purpose of this paper is to present a technique to extend the functionality and the application fields of a spatially selective coding within a JPEG2000 framework. The image quality drop between the Regions of Interest (ROI) and the background (BG) is considered. From the conventional point of view, the reconstructed image quality steeply drops along the ROI boundary; however this effect can be considered or perceived to be objectionable in some situations. We here propose a simple quality decay management, which makes use of concentric ROI with different scaling factors. This allows the technique to be perfectly consistent with the JPEG2000 part 2 ROI definition and description. The proposed techniques may have a significant impact on applications where both coding rate minimization and coded image quality are important and/or become critical factors. Experiments and examples demonstrate the benefits of the presented approach(1).