Partial light field tomographic reconstruction from a fixed-camera focal stack

TL;DR

This paper introduces a method for reconstructing high-resolution 4D light fields from a fixed-camera focus stack by estimating focus and depth maps and applying masked back-projection for partial light field reconstruction, enabling perspective shifts from a single viewpoint.

Contribution

A novel approach combining focus map estimation, depth calibration, and masked back-projection for partial light field reconstruction from fixed-camera images.

Findings

Achieves high angular resolution with a fixed camera setup.

Enables rendering of perspective shifts from a single viewpoint.

Demonstrates effective partial light field reconstruction using focus stacks.

Abstract

This paper describes a novel approach to partially reconstruct high-resolution 4D light fields from a stack of differently focused photographs taken with a fixed camera. First, a focus map is calculated from this stack using a simple approach combining gradient detection and region expansion with graph-cut. Then, this focus map is converted into a depth map thanks to the calibration of the camera. We proceed after this with the tomographic reconstruction of the epipolar images by back-projecting the focused regions of the scene only. We call it masked back-projection. The angles of back-projection are calculated from the depth map. Thanks to the high angular resolution we achieve by suitably exploiting the image content captured over a large interval of focus distances, we are able to render puzzling perspective shifts although the original photographs were taken from a single fixed camera at a fixed position.