Tag: c++

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 ­čÖé 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 002 Weak Perspective

Highlights: In this post we will talk about how human vision can be tricked with a Perspective Projection model, and we will present one new model, which is called Weak Perspective. Tutorial Overview: Human vision Weak perspective 1. Human vision Humans are very sensitive to this structure of parallel lines and what they convey to us. Probably most of you have seen this Muller-Lyer illusion. Which one of these lines is longer? And you probably…
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OpenCV #010 Circle Detection Using Hough Transform

Highlights: In this post we will learn about analysing a given image to find circles detected in that image. Tutorial Overview: Intro Detecting Circles with Hough Hough Transform for Circles Code 1. Intro In the previous post, we saw how we can detect and find lines on images using Hough Transform. Now let’s move to something just a little bit more complicated, circles. Let’s start with the equation of a circle: $$ ( x_{i}-a )^{2}+(…
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OpenCV #009 Line Detection Using Hough Transform

  Highlights: In this post, we will learn how to analyze images and detect basic features: lines! We will describe a well known Hough transform that will help us to do this task. Let’s roll! Tutorial Overview: Line Detection Hough Space Polar Representation for Lines Code for Detecting Lines in Python and C++ 1. Line Detection Human driver on a regular day performs lane detection. This is a crucial task in order to keep the…
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