Programming Interactivity, 2nd Edition

Chapter 14. Motion and Gestures

This chapter is about capturing images and movement and turning them into meaningful information. One part of it is going to be largely about one library, OpenCV, and using the library in Processing and openFrameworks. The other part is going to be about different techniques for capturing different gestures and movements, both with OpenCV and without, and then deriving meaningful information from those. This is an important chapter because it is where you’ll learn how to turn the gestures and movements of a user, or other kinds of movement in an image, into meaningful input for an application. As anyone paying attention to the development of devices and the advancement of user interface and experience concepts over the past few years can tell you, this topic is one of the most interesting and important ideas in contemporary device design. Surfaces, tangible interaction devices, and free gesture interfaces have been incorporated in many different kinds of devices in the past few years.

Computer vision is a field of computing concerned with creating “seeing” applications by feeding an application a series of images, like a video, or a single image. Usually these images are analyzed for something in particular, such as looking for a light or for a face. Unlike human sight, a computer needs a good deal of instruction on what it should be looking for in an image. Computer vision techniques can be used to find fingertips, track gestures, find faces, or simply ...