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

Binary images


The images that we have been dealing with so far are grayscale images. Programmatically, we have represented them using a Mat object having the equivalent of an unsigned char type. This means that each pixel value was permitted to be an integer between 0 and 255 (inclusive). This allowed us to represent not only black and white but also all the intermediate shades of gray as well. If you show these images to a layman (or anyone who isn't familiar with image processing parlance), they would no doubt label them as black-and-white. After all, grayscale images resemble the kind of pictures that you would expect to see on a black-and-white television.

However, this chapter will make a clear distinction between grayscale and black-and-white images. You will learn that in computer vision jargon, these two terms signify substantially different things. When we talk of black-and-white images in the context of image processing, we literally mean to say that the only allowable colors are...