Using cross-ratios to model curve data for aircraft recognition
This study proposes a novel method that utilizes the projective invariance of NURBS (nonuniform rational B-splines) and cross-ratios to recognize aircraft in images. An aircraft contour extracted from an image can be fitted by a NURBS curve in approximation, and a skew-symmetry detection method is employed to determine the start point of the contour for the fitting curve. The control points on the fitting curve are then utilized to calculate a set of cross-ratios to represent the aircraft contour, and a small database is established for aircraft recognition. Moreover, all real cross-ratios are converted to integral cross-ratios to increase the error tolerance and matching facilitation. The experimental results demonstrate that the proposed method is robust and effective in aircraft recognition.
cross-ratio projective invariant nurbs curve