[M-IS05] Geomaterials in cultural heritage: weathering, investigation techniques, and conservation

[MIS05-02] Clarification of obscure characters by using SfM 3D photogrammetry on disaster memorial stelae

Reon Goto², *Chiaki T. Oguchi¹ (1.Institute for Environmental Science and Technology, Graduate School of Science and Engineering, Saitama University, 2.Department of Engineering, Saitama University)

Keywords:disaster memorial stelae, SfM

One of the essential roles of disaster memorial stelae is to convey the events that happened the last time. When considering the protection of such stelae, one of the most important must be keeping the values of the text expressed in the inscription. However, those inscriptions tend to weather for a long time, and sometimes cannot interpret anymore. Therefore, the present study tries to create a 3D model of outdoor stelae in their current state. SfM (Structure from Motion) photogrammetry is used to create a three-dimensional structure by extracting feature points in captured images and analyzing common points between adjacent images. By storing it as a 3D digital image and using the coordinates of the obtained 3D data, inscriptions on the stelae can be reproduced. In addition, the method helps decipher obscure characters in the handheld and less expensive easy apparatus without any effects by colour information such as moss and mould.