Reversible EZWBased Image Compression Using BestTransform Selection and Selective Partial Embedding
Michael D. Adams and Andreas Antoniou
A besttransform selection method and a selective partial embedding technique are proposed for use in a reversible embedded
image compression system based on the embedded zerotree wavelet (EZW) coding scheme. Together, these approaches are shown
to yield significantly better compression performance than a baseline system employing fully embedded EZW coding in conjunction
with a single fixed transform such as the S+P transform.
Reversible embedded image compression, wavelet/subband coding.
In recent years, there has been a growing interest in reversible embedded image compression systems [1--3]. One
of the main advantages of such systems is their ability to efficiently handle progressive lossytolossless transmission
of images. In this paper, we describe two techniques for improving the lossless coding performance of a reversible
embedded image compression system based on the embedded zerotree wavelet (EZW) coding scheme . In Section II,
we propose a besttransform selection scheme, its main benefits being simplicity and compatibility with efficient lossless
compression. In Section III, we adapt the EZW scheme to handle reversible compression, and propose a selective partial
embedding technique that improves performance by relaxing the embedding constraint at high bit rates. In Section IV,
we combine these two techniques and analyze the performance of the resulting system. As will be seen, the performance
of our modified coder is much better than that of a baseline system employing the fully embedded EZW coding scheme