Book Image

Computer Vision for the Web

By : Foat Akhmadeev
Book Image

Computer Vision for the Web

By: Foat Akhmadeev

Overview of this book

This book will give you an insight into controlling your applications with gestures and head motion and readying them for the web. Packed with real-world tasks, it begins with a walkthrough of the basic concepts of Computer Vision that the JavaScript world offers us, and you’ll implement various powerful algorithms in your own online application. Then, we move on to a comprehensive analysis of JavaScript functions and their applications. Furthermore, the book will show you how to implement filters and image segmentation, and use tracking.js and jsfeat libraries to convert your browser into Photoshop. Subjects such as object and custom detection, feature extraction, and object matching are covered to help you find an object in a photo. You will see how a complex object such as a face can be recognized by a browser as you move toward the end of the book. Finally, you will focus on algorithms to create a human interface. By the end of this book, you will be familiarized with the application of complex Computer Vision algorithms to develop your own applications, without spending much time learning sophisticated theory.
Table of Contents (13 chapters)

Introducing the tracking.js library


Let me give you a quick review of the tracking.js library. It is a great library that helps you with object detection, tracking, and image filtering. You can download it from http://trackingjs.com. In this section, we will focus on the the installation of the library and how both JSFeat and tracking.js libraries can be used together.

Installation and image loading

Actually, the installation of a JavaScript library is straightforward. You just need to add a script file to your <head> tag:

<script src="js/tracking.js"></script>

The image loading is done using the context, just like we did in the previous chapter:

var imageData = context.getImageData(0, 0, cols, rows);

In contrast to the JSFeat library, tracking.js works with arrays and it does not create a new object for images (as you remember, it is the matrix_t function for JSFeat). In that case, how do we apply a simple operation? Here is an example of how to convert a colored image to grayscale...