ABSTRACT
It has been demonstrated previously that isotropy of wavelets is advantageous for the detection of pointwise singularities. The influence of the isotropy is studied here for a broader class of operators. We compare Gabor filters, which provide a relatively high directionality, the spherical wavelet and the Mexican Hat function, which is isotropic. From experiments on different backgrounds and with defects of varying size, we observe a clear influence of sphericity on the detection of small singularities.
