GitHub Repository

Camera calibration library with spline and parametric distortion models. Maximally powerful, minimally complex.

216 starsC++

Lensboy – Lightweight camera calibration with spline distortion models

Name: Lensboy – Lightweight camera calibration with spline distortion models
Availability: InStock
Author: robertleoj

by robertleoj·Mar 1, 2026·2 points·2 comments

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AI Analysis

●●●BangerNiche GemSolve My Problem

Spline distortion beats OpenCV for cheap lenses; swappable API outclasses mrcal's overhead.

Strengths

•Spline distortion models handle arbitrary lens distortion where OpenCV polynomial fails—solves real wide-angle/cheap lens problem
•Trivial pip install with zero-dependency runtime mode vs. mrcal's bloated dependency tree
•Notebook-friendly Python API with built-in analysis tools (board warp, outlier filtering) that save hours

Weaknesses

•Audience is narrow—only roboticists and CV engineers doing calibration will benefit
•Spline models are known in academic vision; novelty is in packaging, not method

Post Description

I do a lot camera calibration.

As my need for accuracy increased, I started using mrcal, a great camera calibration tool. But I found it didn't fit my workflow well in terms of workflow and as a software dependency.

What I wanted from a calibration library was:

Accuracy (obviously)

Trivial dependency, both calibration time and runtime

Simple and notebook-friendly python API

Support for both OpenCV and spline distortion models

Great built-in analysis tools

Board warp estimation

Outlier filtering

So that's what I built!

Would love feedback from other robotics / computer vision folks.