Super-Resolved Fourier-Slice Refocusing in Plenoptic Cameras

Plenoptic cameras are a new type of sensors that capture the four-dimensional lightfield of a scene. Processing the recorded lightfield, these cameras extend the capabilities of current commercial cameras offering the possibility of focusing the scene after the shot or obtaining 3D information. Conventional photographs focused on certain planes can be obtained through projections of the four-dimensional lightfield onto two spatial dimensions. These photographs can be efficiently computed using the Fourier Slice technique, but their resolution is limited since a plenoptic camera trades off spatial resolution for angular resolution. In order to remove this limitation, several super-resolution methods have been recently developed to increase the spatial resolution of plenoptic cameras. In this paper, we study the super-resolution problem in plenoptic cameras and show how to efficiently compute super-resolved photographs using the Fourier Slice technique. We also show how several existing super-resolution methods can be seen as particular cases of this approach. Experimental results are provided to show the validity of the approach and its extension to super-resolved all-in-focus image computation and 3D processing is studied.