Precise estimation of the projection of a shape from a pixel coverage representation

Measuring width and diameter of a shape are problems well studied in the literature. A pixel coverage representation is one specific type of digital fuzzy representation of a continuous image object, where the (membership) value of each pixel is (approximately) equal to the relative area of the pixel which is covered by the continuous object. Lately a number of methods for shape analysis use pixel coverage for reducing error of estimation. We introduce a novel method for estimating the projection of a shape in a given direction. The method is based on utilizing pixel coverage representation of a shape. Performance of the method is evaluated by a number of tests on synthetic objects, confirming high precision and applicability for calculation of diameter and elongation of a shape.