Book Image

OpenCV 4 Computer Vision Application Programming Cookbook - Fourth Edition

By : David Millán Escrivá, Robert Laganiere
Book Image

OpenCV 4 Computer Vision Application Programming Cookbook - Fourth Edition

By: David Millán Escrivá, Robert Laganiere

Overview of this book

OpenCV is an image and video processing library used for all types of image and video analysis. Throughout the book, you'll work with recipes to implement a variety of tasks. With 70 self-contained tutorials, this book examines common pain points and best practices for computer vision (CV) developers. Each recipe addresses a specific problem and offers a proven, best-practice solution with insights into how it works, so that you can copy the code and configuration files and modify them to suit your needs. This book begins by guiding you through setting up OpenCV, and explaining how to manipulate pixels. You'll understand how you can process images with classes and count pixels with histograms. You'll also learn detecting, describing, and matching interest points. As you advance through the chapters, you'll get to grips with estimating projective relations in images, reconstructing 3D scenes, processing video sequences, and tracking visual motion. In the final chapters, you'll cover deep learning concepts such as face and object detection. By the end of this book, you'll have the skills you need to confidently implement a range of computer vision algorithms to meet the technical requirements of your complex CV projects.
Table of Contents (17 chapters)

Computing depth from a stereo image

Humans view the world in three dimensions using their two eyes. Robots can do the same when they are equipped with two cameras; this is called stereo vision. A stereo rig is a pair of cameras mounted on a device, looking at the same scene and separated by a fixed baseline (that is, the distance between the two cameras). This recipe will demonstrate how a depth map can be computed from two stereo images by computing the depth correspondence between the two views.

Getting ready

A stereo vision system is generally made of two side-by-side cameras looking toward the same direction. The following diagram illustrates such a stereo system in a perfectly-aligned configuration:

Under this ideal...