Abstract：Finding efficient features which are invariant under affine transformation is the key to recognizing the images captured at different angles. Affine invariants, such as affine Gaussian descriptors, are derived in this paper. The covariance matrix of the given image is computed at first. Then its eigenvalues and eigenvectors are calculated, by which a set of ellipses with the same center are generated. Finally, affine Gaussian descriptors are derived based on 2dimensional Gaussian function and image compactification theory. Numerical experiments are carried out and the results show that the performance of affine Gaussian descriptors is high.
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