Book Image

Computer Vision with OpenCV 3 and Qt5

By : Amin Ahmadi Tazehkandi
4 (1)
Book Image

Computer Vision with OpenCV 3 and Qt5

4 (1)
By: Amin Ahmadi Tazehkandi

Overview of this book

Developers have been using OpenCV library to develop computer vision applications for a long time. However, they now need a more effective tool to get the job done and in a much better and modern way. Qt is one of the major frameworks available for this task at the moment. This book will teach you to develop applications with the combination of OpenCV 3 and Qt5, and how to create cross-platform computer vision applications. We’ll begin by introducing Qt, its IDE, and its SDK. Next you’ll learn how to use the OpenCV API to integrate both tools, and see how to configure Qt to use OpenCV. You’ll go on to build a full-fledged computer vision application throughout the book. Later, you’ll create a stunning UI application using the Qt widgets technology, where you’ll display the images after they are processed in an efficient way. At the end of the book, you’ll learn how to convert OpenCV Mat to Qt QImage. You’ll also see how to efficiently process images to filter them, transform them, detect or track objects as well as analyze video. You’ll become better at developing OpenCV applications.
Table of Contents (19 chapters)
Title Page
Dedication
Packt Upsell
Foreword
Contributors
Preface

Understanding histograms


As was mentioned in the introductory part of this chapter, there are a concepts in computer vision that are especially important when dealing with video processing and the algorithms we'll talk about later on in this chapter. One of those concepts is histograms. Since understanding histograms is essential to understanding most of the video analysis topics, we'll go through quite a bit of information about them in this section, before moving on to the next topics. A histogram is often referred to as a way of representing the distribution of data. It is a very simple and complete description, but let's also describe what it means in terms of computer vision. In computer vision, a histogram is a graphical representation of the distribution of pixel values in an image. For example, in a grayscale image, a histogram will be a graph representing the number of pixels that contain each possible intensity in the grayscale (a value between 0 and 255). In an RGB color image...