A 4-D dual-fan filter bank for depth filtering in light fields

A light field is a four-dimensional (4-D) representation of the light permeating a scene-it parameterizes light rays as a function of position and direction. Such a structure can be measured using a specialized camera and can be used to render novel views of the scene it represents. It has previously been shown that the light field model of a scene may be filtered for a single depth by employing frequency-planar filters. Here, we show how a light field may be selectively filtered for a range of depths by forming a 4-D frequency passband that surrounds the intersection of two 4-D fans. A newly proposed cascaded filter bank is shown to approximate this passband, and its effectiveness is demonstrated on two scenes, both of which contain occlusions. Results are compared with those previously obtained using 4-D frequency-planar filters.