Who shot the picture and when?

Abstract

Consider a set of images corresponding to a dynamic scene captured using multiple hand-held cameras. Assuming that we do not have any other information about the camera settings and the dynamic scene, we would like to identify the cameras which captured each of these images. Further, we would like to estimate the order in which these images were captured by each of the cameras. We address this challenging problem using principles derived from multiple view geometry and unsupervised learning techniques. We show that the camera identification problem can be modelled as clustering of the affine camera matrices estimated from the images. We show that homography estimation from the static regions of the scene enables us to order the images captured by each camera individually. Apart from discussing the advantages of the proposed approach, we conclude the paper providing the limitations of the approach and future directions.