Data collection guide for Overlapping Camera Calibration (Multiple-Targets)
Display surface
The surface used for displaying the charuco board should be completely flat, i.e. zero curve
We should select a surface with zero/minimal edge, i.e. non display area
There should be no distortion or changes made by the display to the charuco boards while displaying if using a digital display
The brightness/ligth reflected from the surface should be balanced to have clear image. not too low or not too high.
Target
The target should be generated to match perfectly fit the surface to maximize the target display and get the measurements precise.
All the charuco boards should be of different dictionaries for better detection
Use the targets in pdf form to avoid any scaling done by the display app if using a digital display
Surroundings and Setup
The room should be lit in a balanced way such that the clarity of captured images is maximum
The complex dictionary should be nearer for better detection. The order of preference is 7×7 > 6×6 > 5×5 > original.
Place the camera such that to 1. Avoid including areas without charuco displayed. 2. The number of common detected points between the left and right camera is maximum
The Angles between the targets should be such that it covers the complete field of view of both the cameras depending on the distance between the monitor and the cameras and size of the targets
The cameras should be placed on a stable platform and image clicks should be triggered wireless/ with utmost care to avoid any disturbance that can change the setup's ground truth.
Beneath are examples of good Setup images:
Beneath are examples of bad data collection:
Square Length Calculation when using monitors
These formulas are useful when the charuco board generated fits precisely to the display used both in length and width with no padding
If the manufacturer doesn't provide the length and width of the display but provides the diagonal length (dl) and the ratio of the length and width ( i.e L : W) then the total display area is
Last updated