Book Image

Raspberry Pi for Secret Agents

By : Stefan Sjogelid
Book Image

Raspberry Pi for Secret Agents

By: Stefan Sjogelid

Overview of this book

Ever wished you could play around with all the neat gadgets your favorite spies use (like James Bond or Michael Westen)? With the introduction of the remarkable Raspberry Pi and a few USB accessories, anybody can now join in on the action.Discover how to turn your Raspberry Pi into a multipurpose secret agent tool! Through a series of fun, easy-to-follow projects you'll learn how to set up audio/video surveillance, explore your Wi-Fi network, play pranks on your friends, and even learn how to free your Raspberry Pi from the constraints of the wall socket.Raspberry Pi for Secret Agents starts out with the initial setup of your Raspberry Pi, guides you through a number of pranks and secret agent techniques, and then shows you how to apply what you've learned out in the real world. Learn how to configure your operating system for maximum mischief and start exploring the audio, video, and Wi-Fi projects. Learn how to record, listen, or talk to people from a distance and how to distort your voice. You can even plug in your webcam and set up a motion detector with an alarm, or find out what the other computers on your Wi-Fi network are up to. Once you've mastered the techniques, combine them with a battery pack and GPS for the ultimate off-road spy kit.
Table of Contents (12 chapters)
Raspberry Pi for Secret Agents
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Detecting an intruder and setting off an alarm


Let's dive right in to the wonderful world of motion detection!

The basic idea of motion detection is pretty simple from a computer's point of view—the motion detection software processes a continuous stream of images and analyzes the positions of the pixels that make up the image. If a group of contiguous pixels above a certain threshold starts to change from one frame to the next, that must be something moving. The tricky part of motion detection is weeding out false positives triggered by naturally occurring changes in light and weather conditions.

  1. We'll be working with a motion detection application called Motion. Install it using the usual command:

    pi@raspberrypi ~ $ sudo apt-get install motion
    
  2. With Motion installed, the next step is to create a configuration file for our webcam. The Motion installation puts a sample configuration file inside the /etc/motion directory. We will use this configuration file as a template and modify it for our...