To match two images some common features are needed. Low level image features like the image centroids, principle axes, edges and corners are often used. 16 same, these point sets must be the same. Belkasim et al. The order is p q.
Typical examples are recognition of objects in the scene against a database, template matching, etc.
Much effort has been spent to find invariants to imaging geometry, particularly to linear and projective transformations. On the other hand, only few invariants to convolution have been described in the literature. S. O. Belkasim, M. Shridhar, and M. Ahmadi. In a shorter form, this work was submitted to the journal Pattern Recognition Letters. In the case of a digital image, the double integral in eq.