Camera Calibration

Overview #

ZED cameras undergo an extensive and rigorous multi-step factory calibration process to ensure accurate camera parameter estimation. This calibration defines key characteristics such as focal length, field of view, and stereo alignment, which are essential for various computer vision and imaging applications.

The following parameters can be retrieved for each eye and resolution:

  • Focal length: fx, fy.
  • Principal points: cx, cy.
  • Lens distortion: k1, k2, k3, p1, p2.
  • Horizontal, vertical and diagonal field of view.
  • Stereo calibration: rotation and translation between left and right eye.

Using the API #

Camera parameters are available in CalibrationParameters. They can be retrieved using getCameraInformation().

CalibrationParameters calibration_params = zed.getCameraInformation().camera_configuration.calibration_parameters;
// Focal length of the left eye in pixels
float focal_left_x = calibration_params.left_cam.fx;
// First radial distortion coefficient
float k1 = calibration_params.left_cam.disto[0];
// Translation between left and right eye on x-axis
float tx = calibration_params.stereo_transform.getTranslation()[0];
// Horizontal field of view of the left eye in degrees
float h_fov = calibration_params.left_cam.h_fov;

calibration_params = zed.get_camera_information().camera_configuration.calibration_parameters
# Focal length of the left eye in pixels
focal_left_x = calibration_params.left_cam.fx
# First radial distortion coefficient
k1 = calibration_params.left_cam.disto[0]
# Translation between left and right eye on x-axis
tx = calibration_params.stereo_transform.get_translation().get()[0]
# Horizontal field of view of the left eye in degrees
h_fov = calibration_params.left_cam.h_fov

CalibrationParameters calibration_params = zed.getCameraInformation().cameraConfiguration.calibrationParameters;
// Focal length of the left eye in pixels
float focal_left_x = calibration_params.leftCam.fx;
// First radial distortion coefficient
float k1 = calibration_params.leftCam.disto[0];
// Translation between left and right eye on x-axis
float tz = calibration_params.Trans.x;
// Horizontal field of view of the left eye in degrees
float h_fov = calibration_params.leftCam.hFOV;

📌 Note: If self-calibration is enabled, calibration parameters can be re-estimated and refined by the ZED SDK at startup. Updated parameters will be available in CalibrationParameters.