Book Image

OpenNI Cookbook

By : Soroush Falahati
Book Image

OpenNI Cookbook

By: Soroush Falahati

Overview of this book

The release of Microsoft Kinect, then PrimeSense Sensor, and Asus Xtion opened new doors for developers to interact with users, re-design their application’s UI, and make them environment (context) aware. For this purpose, developers need a good framework which provides a complete application programming interface (API), and OpenNI is the first choice in this field. This book introduces the new version of OpenNI. "OpenNI Cookbook" will show you how to start developing a Natural Interaction UI for your applications or games with high level APIs and at the same time access RAW data from different sensors of different hardware supported by OpenNI using low level APIs. It also deals with expanding OpenNI by writing new modules and expanding applications using different OpenNI compatible middleware, including NITE. "OpenNI Cookbook" favors practical examples over plain theory, giving you a more hands-on experience to help you learn. OpenNI Cookbook starts with information about installing devices and retrieving RAW data from them, and then shows how to use this data in applications. You will learn how to access a device or how to read data from it and show them using OpenGL, or use middleware (especially NITE) to track and recognize users, hands, and guess the skeleton of a person in front of a device, all through examples.You also learn about more advanced aspects such as how to write a simple module or middleware for OpenNI itself. "OpenNI Cookbook" shows you how to start and experiment with both NIUI designs and OpenNI itself using examples.
Table of Contents (14 chapters)
OpenNI Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Tracking hands


In this recipe, we are going to expand on the previous recipe and add hand tracking after recognizing a gesture. Moreover, we will also show the location of a hand in the screen overlying the depth frame data.

Getting ready

Create a project in Visual Studio and prepare it for working with OpenNI and NiTE using the Create a project in Visual Studio 2010 recipe in Chapter 2, OpenNI and C++, and then configure Visual Studio to use OpenGL using the Configuring Visual Studio 2010 to use OpenGL recipe in Chapter 3, Using Low-level Data.

How to do it...

  1. Define the window_w, window_h, and gl_texture variables on top of your source code, below the #include lines, just as with the other examples we wrote using OpenGL and GLUT.

  2. Add the following code right below them:

    nite::HandTracker hTracker;
  3. Copy ReadLastCharOfLine() and HandleStatus() from the first recipe of this chapter and paste it here. Also, copy gl_IdleCallback() from the Initialize and prepare OpenGL recipe in Chapter 3, Using Low...