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)

Scanning an image with neighbor access

In image processing, it is common to have a processing function that computes a value at each pixel location based on the value of the neighboring pixels. When this neighborhood includes pixels of the previous and next lines, you then need to scan several lines of the image simultaneously. This recipe shows you how to do it.

Getting ready

To illustrate this recipe, we will apply a processing function that sharpens an image. It is based on the Laplace operator (which will be discussed in Chapter 6, Filtering the Images). It is indeed a well-known result in image processing that if you subtract its Laplacian from an image, the image edges are amplified, thereby giving a sharper image. This...