Category: OpenCV

CamCal 009 Stereo Geometry – Epipolar lines and Essential Matrix

Highlights: In this post we continue our talk about stereo geometry. We will show the relation between two calibrated cameras. The goal is to transform geometry into algebra, so then the computer can understand it. Tutorial Overview: This post covers the following topics: Intro Stereo Correspondence Stereo Geometry Cross Product 1 From Geometry to Algebra Cross Product 2 Essential Matrix 1. Intro Before we start, we have to remind ourself some things. So first thing…
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CamCal 003 Camera Transformation

Highlights: In this post we will talk about camera calibration technique, and rigid body transformations. You will also see how translation and rotation works. Tutorial Overview: Intro Geometric camera calibration Rigid body transformations Notation Rotation 1. Intro In this post, we’re going to talk about extrinsic camera calibration and here is the model that we are going to use. In particular, we had a system where we had a center of projection (COP) that was…
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Harris Corner Detector 013

OpenCV #013 Harris Corner Detector – Theory

Highlights: In this post we will learn about Harris Corner Detector and how can we use this method to detect corners. We will give a brief overview how this method works, but we’ll not go so seriously with mathematics. We promise 🙂 What is Harris Corner Detector? In many computer vision and machine learning applications we need some feature points which we will track or which will assist us to compare and detect objects or…
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CamCal #012 Stereo Geometry Code

Highlights: In this post we will finish our mini series on stereo geometry. We will wrap some things up, and go through the code related to this. In the last few posts we talked about stereo geometry. We covered many concepts, from basic stuff, such as essential matrix and epipolar lines to the fundamental matrix. Here, we will present a code that can help us to compute them. Tutorial Overview: Detecting key points (SIFT, SURF,…
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CamCal 010 Essential Matrix Computation – an example

Highlights: In this post we will show some essential matrix computation for the example of parallel cameras. In addition, you will see why it can be useful for. Tutorial Overview: This post covers the following topics: Computation The use of the Essential Matrix 1. Computation In the last post we talked about essential matrix and what it does. Now we are going to show how it is computed. So we have two parallel image planes,…
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