更充分利用独立弯曲结构的线状要素Morphing变换方法

Morphing Transformation of Linear Features by Using Independent Bend Structures More Sufficiently

提出更充分利用独立弯曲结构的线状要素Morphing变换方法。该方法首先对不同比例尺表达的对应线状要素分别构建约束Delaunay三角网并建立弯曲森林,然后进行弯曲匹配以获得对应弯曲。鉴于对应弯曲"背面"的独立弯曲结构隐藏于更高层次的大弯曲中,将对应弯曲重新构建约束Delaunay三角网,进而建立其"背面"的弯曲森林,并进行弯曲匹配得到新的对应弯曲。依此递归,更充分地挖掘对应弯曲结构。在此基础上,将所有对应弯曲的对应起点和对应终点都作为断点切割原线状要素,获得对应线段。最后,采用线性插值算法建立各对应线段之间的对应点,并以对应点之间的直线段作为移位路径进行Morphing变换。通过实例分析,验证了本文充分利用独立弯曲结构的方法能够提高对应弯曲特征点的识别能力,从而能够更好地保持弯曲特征点并改善Morphing变换效果。

This paper proposes a morphing approach for linear features by using their independent bend structures more sufficiently.Firstly,the constrained Delaunay triangulations(CDT)of the pair of linear features are respectively constructed.Bend structures are identified and represented by bend forests.Secondly,corresponding bends are obtained by bend matching.To use independent bend structures more sufficiently,the CDT of every pair of the obtained corresponding bends are constructed.Then the new pairs of bend forests on the back-side of these corresponding bends are built.Again,bend matching is implemented on the new pairs of bend forests and new corresponding bends are obtained.This process is iteratively carried out until no more corresponding bends can be found.Thirdly,the starts and ends of all the pairs of corresponding bends are used to split the two original linear features so that corresponding segments are obtained.The linear interpolation algorithm is utilized to detect corresponding points for every pair of the corresponding segments.Lastly,straight-line trajectories are used for morphing.The experimental results show that the proposed approaches can improve the ability of identifying corresponding characteristic points and preserving characteristic points in the process of morphing.