Revolutionizing photogrammetry: using mirrors in single-image photogrammetry

Abstract

The present work introduces a new low-cost prototype® designed for photogrammetric surveys of small objects, using a single photographic shot. The prototype® utilizes the different perspectives of the object presented by a series of mirrors strategically placed in the camera sensor. The set of specular reflections projected on our camera sensor simulates the same effect as taking pictures from equivalent points of each mirror.

The v1 prototype® was presented at the 7th International Workshop "Low-Cost 3D Sensors, Algorithms, Applications" in Würzburg on December 15–16, 2022. It consists of a set of eighteen common mirrors conveniently placed around the object to be digitized, making its reflections converge towards the camera lens. The v2 prototype® presented here is an evolution of the previous one, which replaces the common mirrors with precision ones that have a metallic reflective surface on the front. This modification eliminates the double image formed by the reflective layer and the protective glass.

These prototypes® allow for faster surveys of small inert objects (such as small cultural heritage artefacts like sculptures, engravings, rings, coins, etc.) as well as photogrammetric surveys of small living beings, such as insects, which cannot remain still during traditional photography.