Assignment 2: Structured Lighting for 3D Scanning

Instructor: Gabriel Taubin
Assignment developed by: Douglas Lanman

Figure 1: Structured Light for 3D Scanning. From left to right: a structured light scanning system containing a pair of digital cameras and a single projector, two images of an object illuminated by different bit planes of a Gray code structured light sequence, and a reconstructed 3D point cloud.

Downloads: handout, support code
Gray encoding: man, defocused man, boat, chiquita, drummer, osman, pig, urn
binary encoding: man, defocused man


Introduction

The goal of this assignment is to build a 3D scanner using one or more digital cameras and a single projector. While the "desktop scanner" implemented in the previous assignment is inexpensive, it has limited practical utility. The scanning process requires manual manipulation of the stick, and the time required to sweep the shadow plane across the scene limits the system to reconstructing static objects. Manual translation can be eliminated by using a digital projector to sequentially display patterns (e.g., a single stipe translated over time). Furthermore, various structured light illumination sequences, consisting of a series of projected images, can be used to efficiently solve for the camera pixel to projector column (or row) correspondences.