基于序列图像提高光斑质心定位精度

针对激光模拟射击系统对激光光斑进行快速、高精度质心定位的要求,提出了一种基于视频序列图像的光斑检测与高精度质心定位方法。该方法首先利用帧间差分图像和噪声估计参数对射击突发事件进行检测;然后利用噪声估计方法确定光斑的分割阈值,结合形态学滤波对目标光斑和背景噪声进行有效分割,提取光斑区域,同时降低窗口内外噪声。最后,用4帧差分图像合成1帧高分辨率的图像来抑制图像噪声和计算误差的影响,实现光斑质心的高精度定位。实验结果表明,本文方法的光斑质心定位精度与稳定性均优于传统的方法;其中光斑质心定位精度达到了亚像素级别,稳定性度量平均值为0.000 49,优于传统方法的0.002 97。得到的结果显示,提出的方法有助于提升激光射击系统的性能。

Improvement of localization accuracy of spot centroid based on sequential images

To meet the requirements of a laser firing simulation system for high speed and high accurate location of laser spot centroids , a novel method based on the video sequential images is proposed for the spot detection and spot centroid location .The method firstly detects the firing events by the subtraction image between every two sequential frames and by the estimated noise parameters . Then ,it uses the noise estimation to determine the segmenting threshold of the spot and combines morphologic filtering techniques to extract the spot region out from the background , meanwhile reducing the noises inside and outside of the window .Finally ,one high resolution image is generated from 4 subtraction images to decrease the image noise and computing errors and to improve the locating accuracy of the spot centroid .Experimental results indicate that the spot centroid localization precision of laser spot and the average measurement stability of the proposed method are superior to that of the conventional method .The spot centroid localization precision has been reached to sub-pixel level ,and the average measurement stability is 0 .000 49 ,far better than the conventional 0 .002 97 . The method in this study is conductive to improving the performance of laser firing simulation systems .