Good group sparsity prior for light field interpolation
A light field, which is equivalent to a dense set of multi-view images, has various applications such as depth estimation and 3D display. One of the essential problems is light field interpolation, which is obtaining sufficiently dense views from sparser views. The accuracy of interpolation will be enhance by exploiting an inherent property of a light field. Specifically, an epipolar plane image (EPI), which is a 2D subset of the 4D light field, consists of many lines. This structure induces a sparse representation in the frequency domain, where most of the energy resides on a line passing through the origin. On the basis of this observation, we propose a group sparsity prior suitable for light fields to fully exploit their line structure for interpolation. Our experimental results show that the proposed method can achieve better quality than a state-of-the-art shearlet-based method.