Epipolar Geometry

Projective Constraints and Spatial Reconstruction in Stereo Vision

Vol. I · Part 04

The Fundamental Constraint FF

The Fundamental Matrix F encapsulates the algebraic representation of epipolar geometry between two uncalibrated views. It relates corresponding points in stereo images through a rigorous projective constraint.

Given a point in the primary image plane, its correspondence in the secondary view is constrained to a singular Epipolar Line. This search-space reduction is the cornerstone of efficient stereo matching algorithms.

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Awaiting Matrix Computation

Plate 4.1 — Visualization of Epipolar Line Constraints

Principles of Triangulation

To reconstruct the depth of a scene, we must reverse the projection process. Through Triangulation, we project rays from the optical centers through matching image coordinates. The intersection of these rays in Euclidean space defines the 3D position of the point.

Fig. 4.B — Ray-Intersection Simulation

Plate 4.2 — Ray Intersection and Coordinate Crystallization

Spatial Reconstruction via EE

When camera intrinsics are known, we employ the Essential Matrix E to recover the precise relative pose of the stereo pair. This enabling step allows for the generation of metric 3D point clouds.

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Awaiting Stereo Epipolar Geometry

Plate 4.3 — Sparse 3D Point Cloud Generation