Shape Recovery from Noisy Images by Curve Evolution
نویسنده
چکیده
1: A new approach is presented for recovering shapes from noisy images. First, an edge-strength function, v, at every pixel is determined by implementing a segmentation functional. Then, the zero-crossings of the laplacian of the smoothed image are allowed to evolve under the influence of v. Each point on the zero-crossings moves in the direction of the normal with a velocity consisting of two components, a component proportional to the directional derivative of v in the direction of the normal and a component proportional to curvature. The former pulls the zero-crossings towards the true object boundaries while the latter smooths them, eliminating at the same time extraneous edges. The final result is a representation of the shape outline in the form of a collection of closed curves.
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