Recognition in the wavelet domain: A survey

The use of wavelets has grown enormously since their original inception in the mid-1980s. Since the wavelet data representation combines spatial, freq uency, and scale information in a sparse data representation, they are very useful in a number of image processing applications. This paper discusses current work in applying wavelets to object and pattern recognition. Featur e extraction methods and search algorithms for matching images are discusse d. Some important issues are the search for invariant representations, simi larities between existing applications and the human visual system, and the derivation of wavelets that match specific targets. Results from several e xisting systems and areas for future research are presented. (C) 2001 SPIE and IS&T.