My Raspberry Pi 2 just arrived in the mail yesterday, and man is this berry sweet.

This tiny little PC packs a real punch with a 900mhz quadcore processor and 1gb of RAM. To give some perspective, the Raspberry Pi 2 is faster than the majority of the desktops in my high school computer lab.

Anyway, since the announcement of the Raspberry Pi 2 I’ve been getting a lot of requests to provide detailed installation instructions for OpenCV and Python.

So if you’re looking to get OpenCV and Python up-and-running on your Raspberry Pi, look no further!

In the rest of this blog post I provide detailed installation instructions for both the Raspberry Pi 2 and the Raspberry Pi B+.

I’ve also provided install timings for each step. Some of these steps require a lot of processing time. For example, compiling the OpenCV library on a Raspberry Pi 2 takes approximately 2.8 hours versus the 9.5 hours on the Raspberry Pi B+, so please plan your install accordingly.

Finally, it’s worth mentioning that we’ll be utilizing the Raspberry Pi inside the PyImageSearch Gurus computer vision course. Our projects will include home surveillance applications such as detecting motion and tracking people in a room.

Here’s a quick example of detecting motion and tracking myself as I walk around my apartment on the phone:

Install OpenCV and Python on your Raspberry Pi 2 and B+

UPDATE: The tutorial you are reading now covers how to install OpenCV 3 with Python 2.7 and Python 3 bindings on Raspbian Wheezy. Raspbian Jessie has now replaced Raspbian Wheezy and if this is the first time you are reading this tutorial then in all likelihood you are using Raspbian Jessie. Please use the following updated guides to help you install OpenCV + Python on your Raspberry Pi.

• How to install OpenCV 3.0 on Raspbian Jessie.
• Install guide: Raspberry Pi 3 + Raspbian Jessie + OpenCV 3.

I’m going to assume that you have either your Raspberry Pi 2 or Raspberry Pi B+ unboxed and setup. If you don’t have a Raspberry Pi yet, I definitely suggest picking one up. They are super cheap and a lot of fun to play with.

Personally, I prefer to spend a little extra money and purchase from Canakit — their shipping is fast and reliable, plus their complete ready-to-go bundles are really nice.

Anyway, let’s get into the OpenCV and Python install instructions.

Step 0:

Again, I’m going to assume that you have just unboxed your Raspberry Pi 2/B+. Open up a terminal and we’ll start by updating and upgrading installed packages, followed by updating the Raspberry Pi firmware:

$ sudo apt-get update
$ sudo apt-get upgrade
$ sudo rpi-update

Step 1:

Install the required developer tools and packages:

$ sudo apt-get install build-essential cmake pkg-config

Both build-essential and pkg-config are likely already installed, but just in case they are not, be sure to include them in your apt-get command.

Timings:

Raspberry Pi B+: < 2 minutes

Raspberry Pi 2: < 40 seconds

Step 2:

Install the necessary image I/O packages. These packages allow you to load various image file formats such as JPEG, PNG, TIFF, etc.

$ sudo apt-get install libjpeg8-dev libtiff4-dev libjasper-dev libpng12-dev

Timings:

Raspberry Pi B+: < 5 minutes

Raspberry Pi 2: < 30 seconds

Step 3:

Install the GTK development library. This library is used to build Graphical User Interfaces (GUIs) and is required for the highgui library of OpenCV which allows you to view images on your screen:

$ sudo apt-get install libgtk2.0-dev

Timings:

Raspberry Pi B+: < 10 minutes

Raspberry Pi 2: < 3 minutes

Step 4:

Install the necessary video I/O packages. These packages are used to load video files using OpenCV:

$ sudo apt-get install libavcodec-dev libavformat-dev libswscale-dev libv4l-dev

Timings:

Raspberry Pi B+: < 5 minutes

Raspberry Pi 2: < 30 seconds

Step 5:

Install libraries that are used to optimize various operations within OpenCV:

$ sudo apt-get install libatlas-base-dev gfortran

Timings:

Raspberry Pi B+: < 2 minutes

Raspberry Pi 2: < 30 seconds

Step 6:

Install pip :

$ wget https://bootstrap.pypa.io/get-pip.py
$ sudo python get-pip.py

Timings:

Raspberry Pi B+: < 2 minutes

Raspberry Pi 2: < 30 seconds

Step 7:

Install virtualenv and virtualenvwrapper :

$ sudo pip install virtualenv virtualenvwrapper
$ sudo rm -rf ~/.cache/pip

Then, update your ~/.profile file to include the following lines:

# virtualenv and virtualenvwrapper
export WORKON_HOME=$HOME/.virtualenvs
source /usr/local/bin/virtualenvwrapper.sh

Reload your .profile file:

$ source ~/.profile

Create your computer vision virtual environment:

$ mkvirtualenv cv

Timings:

Raspberry Pi B+: < 2 minutes

Raspberry Pi 2: < 2 minutes

Step 8:

Now we can install the Python 2.7 development tools:

$ sudo apt-get install python2.7-dev

Note: Yes, we are going to use Python 2.7. OpenCV 2.4.X does not yet support Python 3 and OpenCV 3.0 is still in beta. It’s also unclear when the Python bindings for OpenCV 3.0 will be complete so I advise to stick with OpenCV 2.4.X for the time being.

We also need to install NumPy since the OpenCV Python bindings represent images as multi-dimensional NumPy arrays:

$ pip install numpy

Timings:

Raspberry Pi B+: < 45 minutes

Raspberry Pi 2: < 15 minutes

Step 9:

Download OpenCV and unpack it:

$ wget -O opencv-2.4.10.zip http://sourceforge.net/projects/opencvlibrary/files/opencv-unix/2.4.10/opencv-2.4.10.zip/download
$ unzip opencv-2.4.10.zip
$ cd opencv-2.4.10

Setup the build:

$ mkdir build
$ cd build
$ cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local -D BUILD_NEW_PYTHON_SUPPORT=ON -D INSTALL_C_EXAMPLES=ON -D INSTALL_PYTHON_EXAMPLES=ON  -D BUILD_EXAMPLES=ON ..

Timings:

Raspberry Pi B+: < 3 minutes

Raspberry Pi 2: < 1.5 minutes

Compile OpenCV:

$ make

Important: Make sure you’re in the cv virtual environment so OpenCV is compiled against the virtual environment Python and NumPy. Otherwise, OpenCV will be compiled against the system Python and NumPy which can lead to problems down the line.

Timings:

Raspberry Pi B+: < 9.5 hours

Raspberry Pi 2: < 2.8 hours

Finally, we can install OpenCV:

$ sudo make install
$ sudo ldconfig

Timings:

Raspberry Pi B+: < 3 minutes

Raspberry Pi 2: < 1 minute

Step 10:

If you’ve gotten this far in the guide, OpenCV should now be installed in /usr/local/lib/python2.7/site-packages

But in order to utilize OpenCV within our cv virtual environment, we first need to sym-link OpenCV into our site-packages directory:

$ cd ~/.virtualenvs/cv/lib/python2.7/site-packages/
$ ln -s /usr/local/lib/python2.7/site-packages/cv2.so cv2.so
$ ln -s /usr/local/lib/python2.7/site-packages/cv.py cv.py

Step 11:

Finally, we can give our OpenCV and Python installation a test drive:

$ workon cv
$ python
>>> import cv2
>>> cv2.__version__
'2.4.10'

OpenCV and Python is now successfully installed on your Raspberry Pi!

Here is an example of me ssh’ing (with X11 forwarding) into my Raspberry Pi, followed by loading and displaying an image:

Summary

In this blog post I detailed how to install OpenCV and Python on your Raspberry Pi 2 or Raspberry Pi B+. Timings for each installation step were also provided so you could plan out the install accordingly.

As the Raspberry Pi (along with Raspbian/NOOBS) evolves the installation instructions will likely change. If you run across any edge cases or variations in the install instructions, please feel free to let me know. While I can’t promise that I can reply to every email, but I think it would be good to curate a list of methods to setup OpenCV and Python on Raspberry Pi systems.

And in future blog posts we’ll explore how to utilize the camera add-on for the Raspberry Pi.

Until then, take a look at the PyImageSearch Gurus computer vision course. We’ll be utilizing the Raspberry Pi inside the course for a few projects, including building a home surveillance application that can detect motion and people in rooms.