This paper presents an implementation of a visual odometry system as described by David Nister\ud
using Videre Design's STH-DCSG Firewire stereo video head, which runs on an AMD Athlon-based\ud
workstation with 1 GB RAM. The system tracks the 3D position of a calibrated stereo head\ud
as it moves through the environment. Harris corner features are identified in the video stream,\ud
and are then matched and triangulated into 3D points. A RANSAC implementation with a quaternion motion estimation method as its hypothesis generator, is used for pose estimation.\ud
The system is able to estimate movement in the camera's x and y planes with a maximum error\ud
of 12cm for a duration of a minute or longer: A persistent drift in the z dimension (along the\ud
camera optical ray) prevents the extraction of useful movement data along that axis
