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Algorithm of invariant image description by the use of a modified Gabor transform
Abstract:
A scale-invariant algorithm of image description that is derived from the investigations of the neural structure of striate complex modules is proposed. First an image is preprocessed by difference-of-Gaussians functions, then the Gabor expansion in modules of different scales is used, and a group of the most excited modules is looked for with the help of scale weighting functions (SWF's). Finally, the image code is calculated as a linear combination of the output signals from the Gabor modules. The coefficients of this linear combination correspond to the SWF selected in the previous step. The scales of Gabor modules are chosen to be a logarithmic sequence with a half-octave step. Because of the SWF method, the described algorithm takes into account all the image sizes on a continuum between the minimum and the maximum scales of the Gabor modules.
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