Exporting calibration parameters¶
Choose Calibration → Export Parameters to save a calibration for use outside Calib GEOM. The JSON file contains camera models and parameters, the relationships between devices, and target and pose information.
Choose the right export¶
| You want to… | Use |
|---|---|
| Continue working in Calib GEOM Pro | A calibration project, together with the original input files |
| Use the calibration in your software | A parameter export |
| Document the calibration and its results | A calibration report |
| Undistort images without implementing the camera model | Lens distortion maps |
| Convert image points to viewing rays | Unprojection maps |
Project files and parameter exports serve different purposes and cannot be used interchangeably.
Project persistence is a Pro feature. In Web, export results before closing or reloading the page; a parameter export is not a session backup.
Using the parameters¶
Your receiving software must support the same camera model and coordinate conventions. Similar parameter names do not make different models compatible.
- For OpenCV's standard model, choose OpenCV in Calib GEOM and follow Using Calib GEOM parameters in OpenCV.
- For MATLAB's compatible model, choose Matlab and follow Using Calib GEOM parameters in MATLAB.
- For other models, use a compatible implementation or suitable exported maps.
The export records both parameter values and whether they were free, fixed, or disabled during optimization. Keep the stored values when using the model; the state is not an instruction to zero a coefficient.
Coordinates and units¶
Image coordinates are in pixels, starting at zero in the top-left corner, with X increasing rightward and Y downward.
Camera extrinsics describe the transform from the first camera to each other camera. Target poses describe the target rig relative to the first camera. These are different transforms; use the one your application requires.
Rotations use angle-scaled axis vectors in radians. Translations and target coordinates use the same length unit. Calib GEOM's target-spacing input is in millimetres and is converted to metres; externally supplied geometry must use a consistent scale.
Developer resources¶
libCalibGeom is Calib.io's calibration library for software integration. It is a separate product and is not included with Calib GEOM. Its documentation covers model APIs, file parsing, and integration examples.
Calib GEOM's parameter and map exports can also be used with compatible third-party software without libCalibGeom. The requirements depend on the integration you choose.