Book Image

Qt 5 and OpenCV 4 Computer Vision Projects

By : Zhuo Qingliang
4 (1)
Book Image

Qt 5 and OpenCV 4 Computer Vision Projects

4 (1)
By: Zhuo Qingliang

Overview of this book

OpenCV and Qt have proven to be a winning combination for developing cross-platform computer vision applications. By leveraging their power, you can create robust applications with both an intuitive graphical user interface (GUI) and high-performance capabilities. This book will help you learn through a variety of real-world projects on image processing, face and text recognition, object detection, and high-performance computing. You’ll be able to progressively build on your skills by working on projects of increasing complexity. You’ll begin by creating an image viewer application, building a user interface from scratch by adding menus, performing actions based on key-presses, and applying other functions. As you progress, the book will guide you through using OpenCV image processing and modification functions to edit an image with filters and transformation features. In addition to this, you’ll explore the complex motion analysis and facial landmark detection algorithms, which you can use to build security and face detection applications. Finally, you’ll learn to use pretrained deep learning models in OpenCV and GPUs to filter images quickly. By the end of this book, you will have learned how to effectively develop full-fledged computer vision applications with OpenCV and Qt.
Table of Contents (11 chapters)

Summary

In this chapter, we created a new application named Literacy. In this application, we recognized characters on images using the Tesseract library. For images that have well-typeset characters, Tesseract worked well; but for the characters in photos of ordinary everyday life, it failed to recognize them. To fix this issue, we resorted to the EAST model with OpenCV. With a pretrained EAST model, we first detected the text areas in photos and then instructed the Tesseract library to only recognize the characters in the detected regions. At this point, Tesseract performed well again. In the last section, we learned how to grab the desktop as an image and how to select a region on it by dragging the mouse.

We used several pretrained neural network models in this and previous chapters. In the next chapter, we will learn more about them; for instance, how to use pretrained classifiers...