Optimal seamline detection is a key step when composing digital orthophotomaps (DOM) of extensive areas from overlapping ortho‐images. To avoid seamlines passing through buildings when mosaicking, seamline detection between adjacent ortho‐images is casted as a graph‐cut problem. To avoid buildings, colour differences and gradient magnitude derived from the ortho‐images, together with approximate object heights derived from a digital surface model (DSM), are combined for constructing the cost term of the graph. To efficiently obtain an approximate height value for each DOM unit, an expanded normalised DSM is proposed. Furthermore, the designed cost term for final composite ortho‐image merging is weighted to prioritise pixels closest to the nadir point. Experiments with strips of aerial images show that the proposed method obtains seamless mosaicking of ortho‐images without manual work.

中文翻译：

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使用图割优化城市空中正射影像拼接的接缝线优化

从重叠的正射影像组成大面积数字正射影像图（DOM）时，最佳的接缝线检测是关键的一步。为了避免在镶嵌时接缝线穿过建筑物，将相邻正射影像之间的接缝线检测强制转换为图形剪切问题。为了避免建筑物，将正交图像得出的色差和梯度幅度，以及从数字表面模型（DSM）得出的近似物体高度结合在一起，以构建图形的成本项。为了有效地获得每个DOM单元的近似高度值，提出了扩展的归一化DSM。此外，对最终合成正射影像合并的设计成本项进行加权，以优先处理最接近最低点的像素。