针对水下非平行双目成像系统图像匹配时无法进行平行校正，并且不再满足空气中的极线约束条件这一问题，推导出一种适用于水下的极线约束模型。根据摄像机和防水罩间相对位置关系的不同，把水下双目成像方式分为平行成像、共用折射面成像和独立折射面成像三种情况，并推导了后两种情况的极线约束模型。对摄像机进行标定，利用尺度不变特征变换(SIFT)进行立体匹配，推导了参考图上特征点在待匹配图上所对应的曲线，根据待匹配图上特征点是否在曲线上，剔除误匹配点，提高匹配精度。实验结果表明，利用所推导出的水下曲线约束模型，可以有效地剔除误匹配点，降低误匹配率。

In terms of underwater non-parallel binocular image matching not being parallel correction, and no longer satisfying the epipolar constraint in the air, a kind of epipolar constraint model that suitable for underwater is presented. According to the differences of relative position between the camera and waterproof cover, the underwater imaging ways of binocular vision is divided into parallel imaging, common reflection surface imaging and independent reflection surface imaging. And the epipolar constraint model of the last two are deduced. The camera is calibrated. The scale invariant feature transform (SIFT) algorithm can help to match stereo. And corresponding curve of the feature points on reference image is derived. According to whether the corresponding feature is on the curve, the false matching points are eliminated and the matching accuracy are improved. Experimental results show that the underwater curve constraint model can effectively eliminate false matching points, and reduce the error matching rate.