Book Image

Learning OpenCV 3 Application Development

By : Samyak Datta
Book Image

Learning OpenCV 3 Application Development

By: Samyak Datta

Overview of this book

Computer vision and machine learning concepts are frequently used in practical computer vision based projects. If you’re a novice, this book provides the steps to build and deploy an end-to-end application in the domain of computer vision using OpenCV/C++. At the outset, we explain how to install OpenCV and demonstrate how to run some simple programs. You will start with images (the building blocks of image processing applications), and see how they are stored and processed by OpenCV. You’ll get comfortable with OpenCV-specific jargon (Mat Point, Scalar, and more), and get to know how to traverse images and perform basic pixel-wise operations. Building upon this, we introduce slightly more advanced image processing concepts such as filtering, thresholding, and edge detection. In the latter parts, the book touches upon more complex and ubiquitous concepts such as face detection (using Haar cascade classifiers), interest point detection algorithms, and feature descriptors. You will now begin to appreciate the true power of the library in how it reduces mathematically non-trivial algorithms to a single line of code! The concluding sections touch upon OpenCV’s Machine Learning module. You will witness not only how OpenCV helps you pre-process and extract features from images that are relevant to the problems you are trying to solve, but also how to use Machine Learning algorithms that work on these features to make intelligent predictions from visual data!
Table of Contents (16 chapters)
Learning OpenCV 3 Application Development
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface

Histograms in OpenCV


We have just seen the implementation of a very basic and minimalistic histogram using the first principles in OpenCV. The image histogram was basic in the sense that all the bins were uniform in size and comprised only a single pixel intensity. This made our lives simple when we designed our code for the implementation; there wasn't any need to explicitly check the membership of a data point (the intensity value of a pixel) with all the bins of our histograms. However, we know that a histogram can have bins whose sizes span more than one. Can you think of the changes that we might need to make in the code that we recently wrote to accommodate for bin sizes larger than 1? If this change seems doable to you, try to figure out how to incorporate the possibility of non-uniform bin sizes or multidimensional histograms. By now, things might have started to get a little overwhelming for you. No need to worry. As always, OpenCV has you covered!

The developers at OpenCV have provided...