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

Selecting a specific device for accessing depth stream

We discussed about how to retrieve a list of connected devices but we never used this data to select one of those devices; we always used ANY_DEVICE as the parameter for the openni::Device::open() method without even asking ourselves what this parameter is.

In this recipe, we will show you how to select your desired device and open it. Then create openni::VideoStream for the depth sensor of this device.

But first let's talk about the openni::Device::open() method. Actually this method has a parameter of type string (actually a character array) containing the hardware location (Uri) of the desired device. We always used ANY_DEVICE as the parameter of this method until now, but actually ANY_DEVICE is equal to null and is used only for better reading of code. When passing null as the parameter of this method, OpenNI automatically selects the first device in the list of loaded and recognized devices. So if we want to select our desired device...