Photogrammetric and LiDAR integration for the Cultural Heritage metric surveys

In the last few years, LiDAR and image-matching techniques have been employed in many application fields because of their quickness in point cloud generation. Nevertheless, these techniques do not assure complete and reliable results, especially in complex applications such as cultural heritage surveys; furthermore, the use of the data provided by these techniques is limited to experienced users. For this reason, several authors have already suggested how to overcome these problems through a combined use of LiDAR data and image information to reach new interesting products. These works considers the integration as the possibility to share point clouds generated by these techniques but they do not propose a complete and automatic integration. In this paper, a new approach is proposed. This integration is focused on the possibility of overcoming the problems of each technique: LiDAR and multi-image matching techniques combine and share information in order to extract building breaklines in the space, perform the point cloud segmentation and speed up the modelling process in an automatic way. The goal of this work is to reduce the human intervention during these processes (thanks to the automated algorithms) simplifying the work of the users. The algorithm is still in progress; most of the steps have been fully implemented, while others needs of several improvements to show their full potential.