An embedded 3D geometry score for mobile 3D visual search

The scoring function is a central component in mobile visual search. In this paper, we propose an embedded 3D geometry score for mobile 3D visual search (M3DVS). In contrast to conventional mobile visual search, M3DVS uses not only the visual appearance of query objects, but utilizes also the underlying 3D geometry. The proposed scoring function interprets visual search as a process that reduces uncertainty among candidate objects when observing a query. For M3DVS, the uncertainty is reduced by both appearance-based visual similarity and 3D geometric similarity. For the latter, we give an algorithm for estimating the query-dependent threshold for geometric similarity. In contrast to visual similarity, the threshold for geometric similarity is relative due to the constraints of image-based 3D reconstruction. The experimental results show that the embedded 3D geometry score improves the recall-data rate performance when compared to a conventional visual score or 3D geometry-based re-ranking.