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

Event-based reading of users' data


You don't need to call nite::UserTracker::readFrame() and wait for it to return each time you want to read a frame of data from nite::UserTracker. This is because NiTE developers give us this ability to define a callback (also known as event listener) when a new frame becomes available, just as openni::VideoStream does. In this recipe, we are going to cover this feature and rewrite the first recipe of this chapter, this time based on events.

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++.

How to do it...

  1. Add the ReadLastCharOfLine() function from previous recipes to the top of your source code (just below #include lines).

  2. Then add the HandleStatus() function from the previous recipe, right after the ReadLastCharOfLine() function.

  3. Add these lines after the definition of the HandleStatus() function:

    struct uTrackerNewFrameListener...