Book Image

Raspberry Pi 3 Cookbook for Python Programmers - Third Edition

By : Steven Lawrence Fernandes, Tim Cox
Book Image

Raspberry Pi 3 Cookbook for Python Programmers - Third Edition

By: Steven Lawrence Fernandes, Tim Cox

Overview of this book

Raspberry Pi 3 Cookbook for Python Programmers – Third Edition begins by guiding you through setting up Raspberry Pi 3, performing tasks using Python 3.6, and introducing the first steps to interface with electronics. As you work through each chapter, you will build your skills and apply them as you progress. You will learn how to build text classifiers, predict sentiments in words, develop applications using the popular Tkinter library, and create games by controlling graphics on your screen. You will harness the power of a built in graphics processor using Pi3D to generate your own high-quality 3D graphics and environments. You will understand how to connect Raspberry Pi’s hardware pins directly to control electronics, from switching on LEDs and responding to push buttons to driving motors and servos. Get to grips with monitoring sensors to gather real-life data, using it to control other devices, and viewing the results over the internet. You will apply what you have learned by creating your own Pi-Rover or Pi-Hexipod robots. You will also learn about sentiment analysis, face recognition techniques, and building neural network modules for optical character recognition. Finally, you will learn to build movie recommendations system on Raspberry Pi 3.
Table of Contents (23 chapters)
Title Page
Copyright and Credits
Dedication
Packt Upsell
Contributors
Preface
Index

Displaying photo information in an application


In this example, we shall create a utility class to handle photos that can be used by other applications (as modules) to access photo metadata and display preview images easily.

Getting ready

The following script makes use of Python Image Library (PIL); a compatible version for Python 3 is Pillow.

Pillow has not been included in the Raspbian repository (used by apt-get); therefore, we will need to install Pillow using a Python Package Manager called PIP.

To install packages for Python 3, we will use the Python 3 version of PIP (this requires 50 MB of available space).

The following commands can be used to install PIP:

sudo apt-get updatesudo apt-get install python3-pip

Before you use PIP, ensure that you have installed libjpeg-dev to allow Pillow to handle JPEG files. You can do this using the following command:

sudo apt-get install libjpeg-dev

Now you can install Pillow using the following PIP command:

sudo pip-3.2 install pillow

PIP also makes it easy...