In the proposed detection method, a single image was used for the rapid quantitative measurement of the damage area of a building. By using cross-ratio invariability between real and image coordinates, the damage area and the side lengths of the selected region were measured using the vanishing point, the vanishing line, and a line segment with a known length. Perspective transformation and image binarisation were performed on the selected frame to convert the length into area information. The damage area was obtained rapidly from the proportion of pixels in the damage region to pixels in the selected region. Corner detection and subpixel methods were combined to determine measurement errors because of the selection of measurement points. The experimental results from the example test revealed that quantitative area measurement of surface damage on buildings could be realised using the proposed method.

中文翻译：

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使用单个图像测量明显的建筑物损坏

在所提出的检测方法中，使用单个图像对建筑物的损坏区域进行快速定量测量。通过使用实坐标和图像坐标之间的交叉比不变性，使用消失点、消失线和已知长度的线段测量所选区域的损伤面积和边长。对选定的帧进行透视变换和图像二值化，将长度转换为面积信息。根据损伤区域的像素与选定区域的像素的比例，快速得到损伤区域。由于测量点的选择，将角点检测和亚像素方法结合起来确定测量误差。