摘要
针对激光三角测量系统得到的含局部弯曲的光带图像,提出了一种基于傅里叶-极坐标变换算法检测局部弯曲的方法。通过计算得到光带的法线方向,将空域图像在法线方向上进行灰度投影,直接得到了局部弯曲量。该方法计算过程简捷,对随机噪声与光带强度的不一致分布具有较好的免疫力。理论分析与实验测试证实了该方法的有效性。
Aiming at the laser stripe images with the local bending obtained by the laser triangulation measurement system,a method based on the Fourier-polar transformation algorithm to measure the local bending is proposed.Through the computing,the normal direction of laser stripe is obtained.The gray projection of the spatial-domain image along the normal direction is conducted,and the magnitude of the local bending is obtained directly.This method has advantages of a simple computing process and high immunity to random noises and the non-uniform intensity distribution of laser stripe.The theoretical analysis and experimental test verify the effectiveness of this method.
引文
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