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
About the Author
About the Reviewers


In this chapter, we will introduce primary datatypes of the OpenNI and the NiTE along with some basic information about how to access and select a data stream. Then we will try to show you some examples of events triggered by devices such as connecting or disconnecting an OpenNI supported device from computer.

But first, let's get some background about the whole OpenNI's principle first.

The OpenNI object

OpenNI object is the starting point of everything in the framework. Using the OpenNI class we can access a list of connected devices as well as the version of OpenNI itself. Then using this information we can access a device object and read data.

This class uses the singleton pattern, which means there is only one instance of this class and all of its methods are static.

Also in OpenNI 2 we have the ability to register two callback functions by OpenNI object for capturing device connected and device disconnected events.

The device object

Device object is representing the actual physical...