This project details work undertaken on the application of JPEG 2000, the recent
ISO/ITU-T image compression standard based on wavelet technology, to region of
interest (ROI) coding. The paper briefly outlines the JPEG 2000 encoding
algorithm and explains how the packet structure of the JPEG 2000 bit-stream
enables an encoded image to be decoded in a variety of ways dependent upon the
application. The three methods by which ROI coding can be achieved in JPEG 2000
(tiling; coefficient scaling ; and code block selection) are then outlined and
their relative performance empirically investigated. The experimental results
show that there are a number of parameters that control the effectiveness of ROI
coding, the most important being the size and number of regions of interest,
code-block size, and target bit rate. Finally, some initial results are
presented on the application of ROI coding to face images.
Comparison of default JP2K and maxshift ROI coding with two face ROI’s
(0.25bpp).