Automatic Recognition and Localization of Ground Marked Points Based on Template

Hui Cao
School of Remote Sensing and Information Engineering, Wuhan University, Wuhan 430079, China

Abstract. Distributing some ground marked points as ground control points is a common method in photogrammetry. In traditional photogrammetry measurement of the ground control point remains manual or semi-automatic measurement. This paper presents a method which is based on standards template and image matching principle of least squares. Based on the method, ground marked points are automatically detected by processing digital image with ground marked points. This method is based on the laid ground landmarks images which were obtained by the means of photogrammetry. According to different shapes on the ground signs, we can design the template image library. First, according to different marks we use template images to do difference operation for digital images to get energy images, so we can ensure the approximate position of the marks in digital images. Then we do precise orientation by using standard template images and the approximate object images to do least square image matching. Experiments show that method has higher object identification and location capabilities and it can effectively resolve the signs point of automatic identification and location, so to achieve the purpose of automatic measurement ground control points.

Keywords: object recognition, template match, object localization

In: Wan, Y. et al. (eds) Proceeding of the 8th international symposium on spatial accuracy assessment in natural resources and environmental sciences, World Academic Union (Press).

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