Feature Extraction and Image Processing

278 Feature Extraction and Image Processing

function). 3D Fourier descriptors were introduced for analysis of simple shapes (Staib,

1992) and have recently been found to give good performance in application (Undrill,

1997). Fourier descriptors have been also used to model shapes in computer graphics

(Aguado, 2000). Naturally, Fourier descriptors cannot be used for occluded or mixed

shapes, relying on extraction techniques with known indifference to occlusion (the HT,

say). However, there have been approaches aimed to classify partial shapes using Fourier

descriptors (Lin, 1987).

7.3 Region descriptors

So far, we have concentrated on descriptions of the ...