Calibration Guide Overview
MetriCal's calibration is a joint process, which includes calibrating intrinsics and extrinsics at the same time. This overview provides general guidelines for calibration before diving into the specific calibration guides.
General Calibration Principles
The following principles apply to all camera calibration scenarios:
Target Selection
MetriCal supports various calibration targets. Choose a target appropriate for your sensor setup and ensure its measurements are precise and specified in meters.
You can now purchase calibration targets directly from our online store. This store holds all the targets necessary to run through these calibration guides. If you are a company or facility that needs a more sophisticated target setup for automation or production line purposes, contact us at info@tangramvision.com.
That being said, you can always make your own! Find examples for AprilGrid, Markerboard, and Lidar targets in the MetriCal Premade Targets repository on GitLab.
Valid Data Formats
MetriCal takes a number of different input data types, but there are some special considerations that every user should know of. Reference the Valid Data Formats documentation for more details.
Data Quality Considerations
For all camera calibrations, regardless of how many cameras you're calibrating:
- Image Focus: Always ensure targets are in focus
- Field of View Coverage: Capture the target across the entire field of view
- Target Orientations: When using multiple targets, rotate each one a different orientation
- Convergence Angles: Vary the viewing angle to improve parameter estimation
- Motion Clarity: Avoid motion blur by pausing between poses
- Depth Variation: When possible, use non-planar targets or multiple targets at different depths
Sensor Calibration Guides
Good sensor calibration is key to building accurate perception systems. MetriCal helps you calibrate many types of sensors—from a single camera to complex multi-sensor setups, including local navigation systems. Our guides take you through each step of the process, from collecting data to checking your results. We cover single cameras, multiple cameras, camera-LiDAR combinations, and indoor positioning systems with clear instructions and practical tips. Full multi-modal calibrations are also possible in MetriCal. These multi-modal calibrations follow all the same guidelines as their more specialized guides.
Choose the guide below that matches your setup to get started.
Calibration Workflow
- Setup: Prepare your sensor(s) and calibration target(s)
- Data Capture: Follow the guidelines in the specific calibration guide
- Processing: Run MetriCal on the captured data
- Validation: Review the calibration results and data diagnostics
- Refinement: If needed, capture additional data to improve results
For detailed instructions on each calibration type, refer to the specific guides linked above.