دانلود رایگان مقاله بازسازی منحنی فضای Free - form با استفاده از NURBS-snakes

Abstract

In this study, we propose a robust algorithm for reconstructing free-form space curves in space using a Non-Uniform Rational B-Spline (NURBS)-snake model. Two perspective images of the required free-form curve are used as the input and a nonlinear optimization process is used to fit a NURBS-snake on the projected data in these images. Control points and weights are treated as decision variables in the optimization process. The Levenberg–Marquardt optimization algorithm is used to optimize the parameters of the NURBS-snake, where the initial solution is obtained using a two-step procedure. This makes the convergence faster and it stabilizes the optimization procedure. The curve reconstruction problem is reduced to a problem that comprises stereo reconstruction of the control points and computation of the corresponding weights. Several experiments were conducted to evaluate the performance of the proposed algorithm and comparisons were made with other existing approaches.

5. Conclusions

In this study, we proposed a method for reconstructing free-form space curves from their perspective projections using a NURBS-snake model. A nonlinear optimization problem is formulated to approximate the data using the NURBS-snake in the perspective images. We evaluated the performance of the proposed method based on synthetic and real data. We also compared the proposed method and triangulation-based approaches in terms of various types of error. We conclude that the proposed method performs better than the traditional point-based reconstruction approach with noisy images. We also found that the proposed NURBS-snake fitting process converges faster. Thus, the whole curve can be reconstructed