IEEE
International Conference on Image Processing, September 2002
Generalized
Bitplane-by-Bitplane Shift Method for JPEG2000 ROI Coding
Zhou
Wang, S. Banerjee, B. L. Evans
and Alan C. Bovik
Laboratory for Image and Video Engineering (LIVE),
Department of Electrical and Computer Engineering, The University of Texas at
Austin, Austin, TX 78712-1084
Abstract: One interesting feature of the upcoming JPEG2000
image coding standard is support of region of interest (ROI) coding using the
maximum shift (Maxshift) method, which allows for arbitrarily shaped ROI image
compression without shape coding or explicitly transmitting any shape
information to the decoder. The major disadvantage of the Maxshift method is
that it cannot adjust the scaling value which determines the degree of relative
importance between the ROI and the background wavelet coefficients. The
bitplane-by-bitplane shift (BbBShift) method was introduced to support both
arbitrary ROI shape and arbitrary scaling without shape coding. In this paper,
we propose a generalize BbBShift (GBbBShift) method, which delivers much more
flexibility than both Maxshift and BbBShift for ``degree-of-interest" adjustment
of the ROI with trivial reduction of coding efficiency and increase of
computational complexity. Experiments show that it can provide significantly
better visual quality than Maxshift at low bit rates. GBbBShift is not
compliant with the current JPEG2000 definitions. In order to use it, a new ROI
coding mode would need to be added to the standard.