Book Image

Building Computer Vision Projects with OpenCV 4 and C++

By : David Millán Escrivá, Prateek Joshi, Vinícius G. Mendonça, Roy Shilkrot
Book Image

Building Computer Vision Projects with OpenCV 4 and C++

By: David Millán Escrivá, Prateek Joshi, Vinícius G. Mendonça, Roy Shilkrot

Overview of this book

OpenCV is one of the best open source libraries available and can help you focus on constructing complete projects on image processing, motion detection, and image segmentation. This Learning Path is your guide to understanding OpenCV concepts and algorithms through real-world examples and activities. Through various projects, you'll also discover how to use complex computer vision and machine learning algorithms and face detection to extract the maximum amount of information from images and videos. In later chapters, you'll learn to enhance your videos and images with optical flow analysis and background subtraction. Sections in the Learning Path will help you get to grips with text segmentation and recognition, in addition to guiding you through the basics of the new and improved deep learning modules. By the end of this Learning Path, you will have mastered commonly used computer vision techniques to build OpenCV projects from scratch. This Learning Path includes content from the following Packt books: •Mastering OpenCV 4 - Third Edition by Roy Shilkrot and David Millán Escrivá •Learn OpenCV 4 By Building Projects - Second Edition by David Millán Escrivá, Vinícius G. Mendonça, and Prateek Joshi
Table of Contents (28 chapters)
Title Page
Copyright and Credits
About Packt
Contributors
Preface
Index

Chapter 3. Learning Graphical User Interfaces

In Chapter 2An Introduction to the Basics of OpenCV, we learned the basic classes and structures of OpenCV and the most important class, called Mat. We learned how to read and save images and videos and the internal structure in the memory of images. We are now ready to work with OpenCV, but, in most cases, we need to show our image results and retrieve user interaction with our images using a number of user interfaces. OpenCV provides us with a few basic user interfaces to facilitate the creation of our applications and prototypes. To better understand how the user interface works, we are going to create a small application called PhotoTool at the end of this chapter. In this application, we will learn how to use filters and color conversions.

This chapter introduces the following topics:

  • The OpenCV basic user interface
  • The OpenCV Qt interface
  • Sliders and buttons
  • An advanced user interface – OpenGL
  • Color conversion
  • Basic filters