Quaternionic gabor filters for local structure classification

We introduce quaternionic Gabor filters for the classification of local image structure. These filters are constructed as windowed basis functions of the quaternionic Fourier transform. We show that-in contrast to the 2D complex Gabor filters-the quaternionic Gabor filters are intrinsically 2D filters. A generalized phase concept is introduced and compared to the classical one. It is shown how local image structure can be classified by the value of the local quaternionic phase.