Image Representation Based on the Affine Symmetry GroupA. D Calway, Image Representation Based on the Affine Symmetry Group. Proceedings of the IEEE International Conference on Image Processing. ISBN 0-7803-3258-X, pp. 189–192. September 1996. PDF, 151 Kbytes.
The representation of 2-D signals which are symmetric under the affine group of transformations is considered. An extension of the Multiresolution Fourier Transform (MFT) is presented and shown to have a predictable redistribution of energy as a result of affine transformations of the input signal. An approximation based on the discrete MFT then forms the basis of a computationally efficient algorithm for estimating local affine coordinate transformations between pairs of image regions. Results of applying the technique to an image registration problem illustrate its potential.