Computer Vision is one of the popular areas in computer science that have gained widespread importance lately. Besides, the power of personal computers has grown, thus opening the gate for developers to use Computer Vision algorithms directly on end user machines using client-side scripting. Nowadays, the most popular programming language for the web is JavaScript. It allows us to develop complex algorithms and run them directly in a web browser; this solves several major problems—the user needs nothing but a browser to run a web application, and as a developer, you get a lower load on your server. In this book, we will provide a comprehensive overview of the most popular JavaScript libraries and discuss the techniques they provide to help you in your initial steps in exciting fields, such as image processing and Computer Vision. This book covers Computer Vision methods by providing an intuitive overview of each algorithm and showing clear examples of the usage of libraries.
Chapter 1, Math Never Was So Simple! covers most of the necessary math operations that you need for using Computer Vision libraries and developing your own application.
Chapter 2, Turning Your Browser into Photoshop, introduces the most popular image processing techniques that are commonly used in the Computer Vision area.
Chapter 3, Easy Object Detection for Everyone, provides a detailed overview of object detection in photos and videos, starting from the basic examples, such as detecting objects by color, to the more complex examples such as feature detection.
Chapter 4, Smile and Wave, Your Face Has Been Tracked! covers detection of the face and face particles. In addition to this, it gives you an example of head tracking.
Chapter 5, May JS Be with You! Control Your Browser with Motion, extends the topic of object detection to object tracking and provides exhaustive examples. It also demonstrates how to create a human interface using gestures or head motion.
Chapter 6, What's Next? summarizes all that we will do throughout this book. Moreover, it provides references to several libraries that are not presented here.
This book provides an overview of various methods in the Computer Vision area using JavaScript. Knowledge of JavaScript at the beginner level is required. It is totally fine if you know nothing about Computer Vision. However, you will need some basic math knowledge to understand the concepts in the book. To start with, you just need a web browser and your favorite text editor. This book will guide you from the basics of Computer Vision to the most complex algorithms in the JavaScript world.
You will find this book interesting if you want a much easier way to use the power of Computer Vision in web applications. It will also be beneficial for those who want to implement a human interface on their websites, for example, to create a game. Even if you do not want to add the Computer Vision functionality to your website, take a look at what we have here—websites with Computer Vision algorithms will probably be a trend in the future. Even now you can benefit from using client-side scripting for Computer Vision—you will not need to buy extra machines for your backend.
In this book, you will find a number of styles of text that distinguish between different kinds of information. Here are some examples of these styles, and an explanation of their meaning.
Code words in text are shown as follows: "The installation of a JavaScript library is straightforward. You just need to add a script file to your <head> tag."
A block of code is set as follows:
var dataBuffer = new jsfeat.data_t(cols * rows, imageData.data.buffer); var mat = new jsfeat.matrix_t(cols, rows, jsfeat.U8C4_t, dataBuffer); var gray = tracking.Image.grayscale(mat.data, cols, rows, true);
New terms and important words are shown in bold.
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