A 4D frequency-planar IIR filter and its application to light field processing

A 4D frequency-planar filter is described, having a steady-state frequency response with a pass band that approximates that of a 4D plane. It is shown that a light field containing Lambertian surfaces with no occlusions may be selectively filtered for depth using such a filter. Examples are given showing the effectiveness of the filter in scenes with and without occlusions. A technique for effectively reducing the length of the transient response of the filter is also proposed and the effectiveness of this technique is demonstrated.