Camera Calibration

You need a calibrated camera to run SVO. We use the Matrix Vision Bluefox cameras in our lab, which have VGA resolution and global shutter.

SVO supports three camera models:

1. The ATAN model - our preference - which is also used by PTAM. This model uses the FOV distortion model of "Devernay and Faugeras, Straight lines have to be straight, 2001". You can calibrate your camera with this model by using the calibration tool in this package: https://github.com/ethz-asl/ethzasl_ptam We prefer this model because the projection and unprojection can be computed faster than with the other models. Further, the industrial cameras that we use have neglectable tangential distortion.
2. The Pinhole model with three radial and two tangential distortion parameters. This model is standard in OpenCV and ROS. You can use the ROS camera calibration tool: http://wiki.ros.org/camera_calibration
3. The Ocam model by Davide Scaramuzza which can be used to model cameras with high field of view or even omnidirectional cameras. Use the OCamCalib toolbox to calibrate your camera: http://rpg.ifi.uzh.ch/software_datasets.html Although SVO can be used with this camera model, the algorithm does not work yet with omnidirectional cameras.

We save the calibration in YAML format (see examples in svo_ros/param) and include it in the launchfiles (see examples in svo_ros/launch).