Bidimensional shape detection using an invariant approach

摘要

Bidimensional shape detection is a process with high computational complexity. In this work, an algorithm, based on the generalized Hough transform (GHT), is presented in order to calculate the orientation, scale, and displacement of a image shape with respect to a template. To reduce the complexity, the uncoupled of the parameter calculation is carried out. The generation of the invariant information needed by the uncoupled is implemented by using three transformation functions that pair shape edge points. Differences between gradient vector angles are used to choose the paired points. An “a priori” study of the template shape is carried out to select the most suitable values for the difference angles.