Computer vision systems are deployed in the Arctic Ocean to spot icebergs at night. They are flown over the Amazon rainforest to create aerial maps of fires, blights, and illegal logging. They are set up in ports and airports worldwide to scan for suspects and contraband. They are sent to the depths of the Marianas Trench to guide autonomous submarines. They are used in operating rooms to help surgeons visualize the planned procedure and the patient's current condition. They are launched from battlefields as the steering systems of heat-seeking, anti-aircraft rockets.
We might seldom—or never—visit these places. However, stories often encourage us to imagine extreme environments and a person's dependence on tools in these unforgiving conditions. Perhaps fittingly, one of contemporary fiction's most popular characters is an almost ordinary man (handsome but not too handsome, clever but not too clever) who wears a suit, works for the British Government, always chooses the same drink, the same kind of woman, the same tone for delivering a pun, and is sent to do dangerous jobs with a peculiar collection of gadgets.
Bond. James Bond.
This book teaches seriously useful technologies and techniques with a healthy dose of inspiration from spy fiction. The Bond franchise is rich in ideas about detection, disguise, smart devices, image capture, and sometimes even computer vision specifically. With imagination, plus dedication of learning new skills, we can become the next generation of gadget makers to rival Bond's engineer, Q!
Chapter 1, Preparing for the Mission helps us to install OpenCV, a Python development environment, and an Android development environment on Windows, Mac, or Linux systems. In this chapter, we also install a Unity development environment on Windows or Mac.
Chapter 2, Searching for Luxury Accommodations Worldwide helps us to classify images of real estate based on color schemes. Are we outside a luxury dwelling or inside a Stalinist apartment? In this chapter, we use the classifier in a search engine that labels its image results.
Chapter 3, Training a Smart Alarm to Recognize the Villain and His Cat helps us to detect and recognize human faces and cat faces as a means of controlling an alarm. Has Ernst Stavro Blofeld returned with his blue-eyed Angora cat?
Chapter 4, Controlling a Phone App with Your Suave Gestures helps us to detect motion and recognize gestures as a means of controlling a guessing game on a smartphone. The phone knows why Bond is nodding even if no one else does.
Chapter 5, Equipping Your Car with a Rearview Camera and Hazard Detection helps us to detect car headlights, classify their color, estimate distances to them, and provide feedback to a driver. Is that car tailing us?
Chapter 6, Seeing a Heartbeat with a Motion Amplifying Camera helps us to amplify motion in live video, in real time, so that a person's heartbeat and breathing become clearly visible. See the passion!
Chapter 7, Creating a Physics Simulation Based on a Pen and Paper Sketch helps us to draw a ball-in-a-maze puzzle on paper and see it come to life as a physics simulation on a smartphone. Physics and timing are everything!
This book supports several operating systems as development environments, including Windows XP or a later version, Mac OS X 10.6 or a later version, Debian Wheezy, Raspbian, Ubuntu 12.04 or a later version, Linux Mint 13 or a later version, Fedora 18 or a later version, CentOS 7 or a later version, and openSUSE 13.1 or a later version.
The book contains six projects with the following requirements:
Four of these six projects run on Windows, Mac, or Linux and require a webcam. Optionally, these projects can use Raspberry Pi or another single-board computer that runs Linux.
One project runs on Android 2.2 or a later version and requires a front-facing camera (which most Android devices have).
One project runs on Android 2.3 or a later version and requires a rear-facing camera and gravity sensor (which most Android devices have). For development, it requires a Windows or Mac machine and approximately $75 worth of game development software.
Setup instructions for all required libraries and tools are covered in the book. Optional setup instructions for Raspberry Pi are also included.
This book is for tinkerers (and spies) who want to make computer vision a practical and fun part of their lifestyle. You should already be comfortable with 2D graphic concepts, object-oriented languages, GUIs, networking, and command line. This book does not assume experience with any specific libraries or platforms. Detailed instructions cover everything from setting up the development environment to deploying finished apps.
A desire to learn multiple technologies and techniques and to integrate them is highly beneficial! This book will help you branch out to understand several types of systems and application domains where computer vision is relevant, and it will help you to apply several approaches to detect, recognize, track, and augment faces, objects, and motions.
In this book, you will find a number of text styles that distinguish between different kinds of information. Here are some examples of these styles and an explanation of their meaning.
Code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles are shown as follows: "You can edit /etc/modules to check whether bcm2835-v4l2 is already listed there."
A block of code is set as follows:
set PYINSTALLER=C:\PyInstaller\pyinstaller.py REM Remove any previous build of the app. rmdir build /s /q rmdir dist /s /q REM Train the classifier. python HistogramClassifier.py
When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:
<activity
android:name="com.nummist.goldgesture.CameraActivity"
android:label="@string/app_name"
android:screenOrientation="landscape"
android:theme="@android:style/Theme.NoTitleBar.Fullscreen">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name=
"android.intent.category.LAUNCHER" />
</intent-filter>
</activity>Any command-line input or output is written as follows:
$ echo "bcm2835-v4l2" | sudo tee -a /etc/modules
New terms and important words are shown in bold. Words that you see on the screen, for example, in menus or dialog boxes, appear in the text like this: "Click on the link for Bing Search API (not any variant such as Bing Search API – Web Results Only)."
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