Image-based refocusing by 3D filtering

Abstract

This paper presents a novel spatial-invariant filtering method for rendering focus effects without aliasing artifacts from undersampled light fields. The presented method does not require any scene analysis such as depth estimation and feature matching. First, we generate a series of images focused on multiple depths by using the conventional synthetic aperture reconstruction method and treat them as a 3D image. Second we convert it to the alias-free 3D image. This paper shows this conversion can be achieved simply by a 3D filtering in the frequency domain. The proposed filter can also produce depth-of-field effects. © Springer-Verlag Berlin Heidelberg 2007.