A simple, intuitive camera calibration tool for natural images


A simple, intuitive camera calibration tool for natural images

A D Worrall, G D Sullivan and K D Baker

Department of Computer Science

The University of Reading, Berkshire, RG6 2AY, UK

Anthony.Worrall@Reading.ac.uk

Abstract

The paper reports an interactive tool for calibrating a camera, suitable for use in outdoor scenes. The motivation for the tool was the need to obtain an approximate calibration for images taken with no explicit calibration data. Such images are frequently presented to research laboratories, especially in surveillance applications, with a request to demonstrate algorithms. The method decomposes the calibration parameters into intuitively simple components, and relies on the operator interactively adjusting the parameter settings to achieve a visually acceptable agreement between a rectilinear calibration model and his own perception of the scene. Using the tool, we have been able to calibrate images of unknown scenes, taken with unknown cameras, in a matter of minutes. The standard of calibration has proved to be sufficient for model-based pose recovery and tracking of vehicles.

Postscript (2.5Mb)


Last Modified: 05:59pm BST, July 14, 1997