ChArUco Alignment

calib-targets-charuco aligns decoded marker IDs to a board layout and assigns ChArUco corner IDs. Alignment is discrete and fast: it tries a small set of grid transforms and selects the translation with the strongest inlier support.

Alignment pass

• Each decoded marker votes for a board translation under each candidate transform.
• The best translation wins (ties broken by inlier count).
• Inliers are the markers whose (sx, sy) map exactly to the expected board cell for their ID.

Inlier filtering

After alignment is chosen, the detector keeps only inlier markers and assigns ChArUco corner IDs based on the aligned grid coordinates. The final alignment in the result is a GridAlignment that maps detected grid coordinates into board coordinates.