互相关法实现距离选通远距离目标的三维重建

针对距离选通激光主动成像二维切片图像无法提供远距离目标全面空间位置信息的问题，提出了采用阈值法截断灰度级曲线与互相关法提取距离信息相结合的算法对远距离目标进行高精度三维重建。首先，利用阈值法剔除实测灰度级曲线中零值点，从而消除对后续互相关法计算距离值的影响；然后，将每一像素点实测截断灰度级曲线与理想灰度级曲线进行互相关，利用各像素点相关峰值对应的延迟时间推算各点距离值，并结合成像系统参数计算每一像素点的三维坐标；最后，对距离1.2 km处凉亭切片图像进行处理，得到了凉亭目标的三维图像。

Three-dimensional reconstruction for long-range target based on range-gated system realized by Cross-correlation method

One of the greatest drawbacks of range-gated laser active imaging system lies in the plight that the two-dimensional slice could not provide complete spatial information on some remote objects. Aiming at this problem, a three-dimensional reconstruction method that combines the threshold method to cut off the measured gray-scale curve and cross-correlation method to draw range information and could provide relatively high precision was proposed. In the paper, threshold method was firstly utilized to remove the zero points from the measured gray-scale curve to mitigate the following effect on the distance computation that adopts cross-correlation method. Correlate the interceptive measured gray-scale curve of every pixel and the ideal gray-scale curve, the distance of each pixel with the time delay corresponding to the peak value could be deduced and the three-dimensional coordinates of each pixel with the combination of the system parameters were computed. Finally, the three-dimensional reconstruction of the arbor from 1.2 km could be obtained with the procession of the slices.