低照度双目立体显著目标距离测定方法与实现

针对位置已固定的双目立体装置,提出了一种基于非平行模式测距原理的双目系统光轴-光心参数标定方法,减小了光轴-光心位置误测量带来的测距误差;为解决低照度下双目立体视觉中存在的立体匹配误匹配点多、目标识别度低的问题,采取了最大熵法结合整体光强变化的阈值选取方法提取显著目标,提高了目标识别率,搭建了显著目标测距系统.结果表明:采用文中的系统标定与阈值选取方法的双目立体视觉装置在低照度下具有较高的测距精度及目标识别率.

Method and realization of significant target recognition and distance ranging in the binocular stereo vision under low illumination

A calibration method based on the principle of a non parallel ranging model was presented to obtain the parameters of the binocular stereo vision device. The ranging error caused by the non parallel optical axis and the measurement error of optical center distance were decreased. In order to slove the problem that there were lots of error matching pixels and target recognition rate was low under low illumination in the binocular stereo vision, the threshold selection method which combined the maximum entropy and change of light intensity was proposed to extract significant object, the recognition rate was improved. Finally, the significant target recognition system was build. The results show that the binocular stereo vision device, utilizing the method of camera calibration and threshold selection proposed in this paper, has a higher target recognition rate and ranging precision under low illumination.