THE DETAILS
I had an existing project with Arduino to implement a Home Automation system using the Ethernet Shield.
Then, I chanced upon the work of William Wu, who had used Hakim El Hattab's
reveal.js library and a JavaScript and HTML5 based gesture recognition script to change the slides in a sample slideshow.
The obvious step was to integrate the JS script by Wu into my existing Arduino system to give me gesture recognition on a plane and thus give me the
Gesture Controlled Home Automation System.
HOW IT WORKS
The JS script by Wu detects motion in a plane using the webcam and Chrome's HTML5 <video> tag.
It detects motion in UP, DOWN, LEFT and RIGHT directions and I could now command my Arduino to do the following set of actions :
UP = LIGHT ON
DOWN = LIGHT OFF
LEFT = FAN ON
RIGHT = FAN OFF
The JS script sends a JQuery POST request to a PHP script which in turn uses a switch-case block to send a cURL GET request to my Arduino.