Efficient corner detector for 3D point crowd data and application to 3D modeling of structures

Abstract

Recently, a laser scanner has been receiving more attention as a useful tool for real-time 3D data acquisition, and various applications such as city modeling, DTM generation and 3D modeling of cultural heritage were proposed. However, robust filtering for distinguish on- and off-terrain points from point cloud 3D data collected by airborne laser scanner is still issues. In particular, filtering of point cloud 3D data collected by terrestrial laser scanner has more severe problems caused by many occlusion parts, windows, few the deepest points, wall of buildings and so on. In order to perform 3D texture modeling of cultural heritage using terrestrial laser ranging data, texture modeling method are investigated in this paper, and proposed filtering method is based on flatness within 30*30cm. Flatness area (ground surface, wall of structures, etc.) and non-flatness area (trees, bushes, etc.) is classified using measurement result of many target., and non-flatness areas are interpolated using morphological procedure. The filtering method shows very robust result, and the most remarkable point of this filtering method is its ability to obtain break-lines which give important information for 3D modeling since 3D model of historical structure are consists of flatness areas (e.g. roof, wall, pillar). Therefore, surface patch of 3D model is identified by extracting a flatness area which is surrounded by break-line, and 3D model for the patch is generated using point cloud 3D data along the frame of the patch. Furthermore, curve points for surface patch are detected from break-line, and a surface patch is generated in automatically step-by-step, texture modeling will be done with the surface patch and digital image. Therefore, automatic detection of the curve point, which is necessary for model making, is very difficult. Because, break-line includes a lot of small curve points. In this paper, we particularly watched this problem and carried out promotion of efficiency of model making by developing a solution method. With these processes, efficient 3D representation using textured model is performed without any processes. This paper presents 3D textured modeling method for historical structure using terrestrial laser ranging data and break-line by flatness evaluation, detection method of curve point using break-line.