3D reconstruction of intra-cavity objects using a catadioptric imaging system
3D object reconstruction refers to the process of creating a 3D digital model of physical objects using a set of 2D images. A full 360° image of an object can be obtained by taking multiple shots of the object at different angles, and by using photogrammetry software. The initial step of this process, which is image acquisition, already poses a challenge which would hinder the accurate reconstruction of the object. Particularly, when the object we intend to model in 3D is located within a camera-inaccessible cavity, difficulties arise in its 3D reconstruction. Several techniques can be employed to overcome this problem. In this paper, we demonstrate the use of a catadioptric imaging system to solve this image acquisition problem. A replicable workflow for the 3D reconstruction of intra-cavity objects is detailed using said imaging system, in conjunction with the use of only free and open-source software for processing. Following the workflow, results show a successful reconstruction illustrated by a robust 3D model of a spider conch shell.