针对短程无衍射激光图像特点,提出了一种由亮度梯度确定图像中心的方法。利用光斑图像边缘的亮度梯度,设定图像二值化阈值范围,根据二值化结果确定光斑图像边缘点,对于各边缘点,利用圆上两点直径最长的原理,通过直径的中点确定圆心,求出均值,作为光斑图像的中心。本方法速度快、精度高,适合于实时性要求较强的应用场合,已经在实际应用中取得了较好的效果。

Based on the features of the non-diffracting laser image at short distance, a method to center an image by brightness gradient is proposed. The binarization range is provided in acording to brightness gradient of laser circular image edge, the results are used to detect the edge points. The distance of two points on the edge of circle is maximum, the points are on the diameter. So we could find the center that is midpoint of the two points ahead. The mean of all the points is the center of laser circular image. This method is faster in speed and accurate, fitted into real time field. The method is used in practice and got satisfied results.