Shape description of MR brain images

The paper provides a classification of shape representation and description techniques and areview of some of the most important techniques. We examine shape description techniques on thereconstructed boundaries of brain structures (white matter) in the magnetic-resonance (MR)images using the Fourier descriptors for various frequency components in order to characterizebrain structures

Polygonal Approximation of Closed Curves across Multiple Views

Polygon approximation is an important step in the recognition of planar shapes. Traditional polygonal approximation algorithms handle only images that are related by a similarity transformation. The transformation of a planar shape as the viewpoint changes with a perspective camera is a general projective one. In this paper, we present a novel method for polygonal approximation of closed curves that is invariant to projective transformation. The polygons generated by our algorithm from two images, related by a projective homography, are isomorphic. We also describe an application of this in the form of numeral recognition. We demonstrate the importance of this algorithm for real-life applications like number plate recognition and aircraft recognition