针对传统最小二乘影像匹配受影像质量和初值条件限制的问题，结合铅垂线轨迹法（vertical line locus，VLL）与基于共线条件约束的多片最小二乘匹配算法（multiphoto geometrically constrained matching，MPGC）的特点，提出了一种顾及高程平面及视差约束的最小二乘影像匹配算法.该算法基于高程平面约束匹配，在匹配过程中顾及视差约束进行搜索匹配.视差偏移量可为最小二乘匹配提供可靠稳定的初值条件，能够实现影像的高精度匹配.为验证算法的有效性，分别采用铅垂线轨迹法、基于共线条件约束的多片最小二乘匹配算法与该算法进行对比分析实验.结果表明，该算法在匹配准确性以及后续空中三角测量解算方面比上述两种算法更有优势.
Aiming at the problem that the traditional least square image matching algorithm is limited by the image quality and the initial condition, this paper proposes a least square image matching algorithm considering elevation plane and parallax constraints by means of combining the characteristics of the vertical line locus and the multi-slice least square matching algorithm based on collinear constraints. The algorithm is based on elevation plane constraint matching where the parallax constraint is used in searching and matching process. The parallax offset can provide reliable and stable initial condition for the least square matching, realizing precisely matching of images. There experiments are conducted with the vertical line locus method, the multi-slice least square matching algorithm with collinear conditional constraints and with the proposed algorithm, respectively.Experimental results proof that the proposed algorithm has obvious advantages in matching accuracy and subsequent calculation of aerial triangulation, compard with the other two algorithms.
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