 
Summary: Reversible IntegertoInteger Wavelet Transforms
With Improved Approximation Properties
Peter W. van Vugt and Michael D. Adams
Dept. of Elec. and Comp. Eng., University of Victoria, Victoria, BC, Canada
Abstract Reversible integertointeger (ITI) transforms that
approximate linear wavelet transforms have proven extremely
useful in signal coding applications. The coding efficiency achiev
able with such reversible transforms, however, depends on how
well they approximate their parent linear transforms. In this
paper, a simple but effective method for constructing reversible
ITI wavelet transforms which better approximate their parent
linear transforms is proposed. Furthermore, the transforms
obtained with this new method are shown to have superior
performance for signal coding applications.
I. INTRODUCTION
Reversible integertointeger (ITI) wavelet transforms have
proven to be extremely useful in both lossless and lossy
signal coding applications, finding use in many practical
systems (e.g., the JPEG2000 codec [1]). Such transforms are
invertible in finiteprecision arithmetic (i.e., reversible), map
