Light field

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Small survey over light fields

Introduction

A light field describes all light in a scene.
Given a position \(\displaystyle (x,y,z)\) and angle \(\displaystyle (\theta, \phi)\) describing a ray, the 5D function \(\displaystyle L(x,y,z,\theta,\phi)\) is the radiance at that point.

For reasonable scenes, the radiance is consistent along the ray so light fields are actually 4D functions.

Representations

Lightfields can be represented as a set of images along a 2D grid. Each image is captured from a slightly different viewpoint but faces the same object using a sheer projection or rotation.

The easiest way to collect light field data is to simulate it from within a virtual environment using software.

Resources