Crate vision_calibration_linear 

Linear and closed-form calibration building blocks.

This crate provides deterministic, allocation-light solvers that are commonly used as initialization steps before non-linear refinement. The focus is on classic DLT-style methods and minimal solvers with clear numerical assumptions.

Algorithms

• Homography estimation (normalized DLT, optional RANSAC)
• Planar intrinsics (Zhang method from multiple homographies)
• Distortion estimation (Brown-Conrady from homography residuals)
• Iterative intrinsics refinement (alternating K and distortion estimation)
• Planar pose from homography + intrinsics
• Fundamental matrix: 8-point (normalized) and 7-point
• Essential matrix: 5-point minimal solver + decomposition to (R, t)
• Camera pose (PnP): DLT, P3P, EPnP, and DLT-in-RANSAC
• Camera matrix DLT and RQ decomposition
• Linear triangulation (DLT)
• Multi-camera rig extrinsics and hand-eye calibration
• Laserline plane estimation (SVD-based from ray-plane intersections)

Coordinate conventions

• Most solvers accept pixel coordinates directly.
• Essential matrix and P3P/EPnP expect calibrated image points; these functions take intrinsics or assume input is already normalized.
• Pose outputs are T_C_W: transform from world/board coordinates into the camera frame.

Example

use vision_calibration_linear::HomographySolver;
use vision_calibration_core::Pt2;

let world = vec![
    Pt2::new(0.0, 0.0),
    Pt2::new(1.0, 0.0),
    Pt2::new(1.0, 1.0),
    Pt2::new(0.0, 1.0),
];
let image = vec![
    Pt2::new(120.0, 200.0),
    Pt2::new(220.0, 198.0),
    Pt2::new(225.0, 300.0),
    Pt2::new(118.0, 302.0),
];

let h = HomographySolver::dlt(&world, &image).expect("homography failed");
println!("H = {h}");

Non-linear refinement and full pipelines live in vision-calibration-optim and vision-calibration-pipeline and are re-exported via the top-level vision-calibration crate.

Re-exports

pub use camera_matrix::*;

pub use distortion_fit::*;

pub use epipolar::*;

pub use extrinsics::*;

pub use handeye::*;

pub use homography::*;

pub use iterative_intrinsics::*;

pub use laserline::*;

pub use math::*;

pub use planar_pose::*;

pub use pnp::*;

pub use triangulation::*;

pub use zhang_intrinsics::*;

Modules

camera_matrix

Camera matrix estimation and decomposition utilities.

distortion_fit

Closed-form distortion coefficient estimation from homography residuals.

epipolar

Epipolar geometry solvers for fundamental and essential matrices.

extrinsics

Multi-camera rig extrinsics initialization.

handeye

Hand-eye calibration (AX = XB) using Tsai–Lenz.

homography

Homography estimation (plane-induced projective transform).

iterative_intrinsics

Iterative linear intrinsics estimation with distortion refinement.

laserline

Laserline plane estimation from planar target observations.

math

Mathematical utilities for linear calibration algorithms.

planar_pose

Planar pose estimation from a homography.

pnp

Perspective-n-Point (PnP) solvers for camera pose estimation.

prelude

Minimal imports for common planar initialization workflows.

triangulation

Linear triangulation of 3D points from multiple views.

zhang_intrinsics

Zhang-style planar intrinsics initialization.