Filtering medical image using adaptive filter

To date various image filtering approaches are reported, most of them enhance the signal-to-noise ratio (SNR) in different levels with loss of some useful information. In this paper, an adaptive template filtering method is described which can be used to increase SNR and keep the important edge information of medical images. In the proposed method, for each pixel, an optimal template of different shape and coefficients is selected automatically depending on its neighbor pixels. Not being simple extension of the 2D method, sequential filtering of slices in three orthogonal directions implemented the 3D algorithm, which improved existing adaptive template filtering technique, avoiding a burden of enormous search. Simulation and MRI image tests, both 2D and 3D, show that the new adaptive template filter provides higher SNR and sharper edges.