Ma Yunpeng, Zhou Yaqin, Wang Chunkuan, Wu Yi, Zou Yang, Zhang Shan
Appl Opt. 2022 Mar 1;61(7):1675-1686. doi: 10.1364/AO.448184.
Underwater measurement based on stereo vision attaches great importance to camera calibration. However, it is challenging to perform accurate calibration due to the significant refraction presented at the interfaces of air and water. To solve this problem, a calibration method for an underwater binocular vision system based on the optimized refractive model is proposed. First, conventional calibration is performed to obtain basic initial camera parameters using checkerboard images collected in the air. Then, an evolutionary multi-objective function is established according to Snell's law, the refractive light propagation path, and checkerboard geometric relationship. Finally, precise camera parameters and involved refraction parameters are both obtained for underwater target positioning and size measurement by the non-dominated sorting genetic algorithm of the reference point. A group of experiments is performed, and the validity and effectiveness of the proposed calibration algorithm is demonstrated.
基于立体视觉的水下测量非常重视相机校准。然而，由于空气和水的界面处存在显著的折射，进行精确校准具有挑战性。为了解决这个问题，提出了一种基于优化折射模型的水下双目视觉系统校准方法。首先，使用在空气中采集的棋盘格图像进行传统校准，以获得基本的初始相机参数。然后，根据斯涅尔定律、折射光传播路径和棋盘格几何关系建立进化多目标函数。最后，通过参考点的非支配排序遗传算法获得精确的相机参数和相关折射参数，用于水下目标定位和尺寸测量。进行了一组实验，验证了所提校准算法的有效性和实用性。
