Hybrid non-linear filters for locating speckled contaminants in grain

This paper discusses the possible application of morphological operators to the inspection of grain. The particular task that is involved is that of locating contaminants such as rodent droppings. In the following section we describe the background to the problem and show the result of applying morphological operators and nonlinear filters to grain images in order to locate contaminants. We analyse the situation in more detail and show quite where the basic morphological approach needs supplementation.