An Edge-Preserving Filter Modeled After Structures In The Visual Cortex

A novel filter was designed that preserves signal edges better than a linear or a median filter when matched to attain the same amount of noise smoothing. This filter was modeled after well-known properties of neurons in the visual cortex that are only sensitive to visual stimuli of lines tilted in specific directions. Using a similar directional sensitivity, the presence of signal edges in the filter window can be detected and the smoothing applied only in directions that do not cross edges. In the presence of white, Gaussian noise, the minimum SNR must be at least 1/2 to attain superiority in terms of edge preservation of this new directional filter, for lower SNR values its performance may deteriorate ungracefully and a linear filter is the clear choice.