Sami Osborn

Cheirality and Parallax Checks

Using positive-depth and baseline-angle checks to reject geometrically invalid reconstructions.

MonoSLAMTechnical note14 Mar 2026SLAMgeometric perception

A valid reconstruction requires positive depth in both camera frames and sufficient triangulation angle.

Practical checks in the pipeline:

  1. Positive depth ratio for triangulated points.
  2. Median parallax threshold to avoid near-degenerate solutions.
  3. Early rejection if reconstructed structure collapses onto a narrow depth band.

These checks prevent apparently successful bootstrap cases from degrading immediately in tracking.