Install dlib and face_recognition on a Raspberry Pi

Instructions tested with a Raspberry Pi 2 with an 8GB memory card. Probably also works fine on a Raspberry Pi 3.

Steps
Download the latest Raspbian Jessie Light image. Earlier versions of Raspbian won’t work.

Write it to a memory card using Etcher, put the memory card in the RPi and boot it up.

Log in. Default username / password is pi / raspberry.

Set up Wifi (if you are using Wifi) according to the Raspberry Pi instructions.

Run sudo raspi-config and configure the basics:

Set up your keyboard layout (It defaults to a British keyboard layout)
Change default user password
Enable the Raspberry Pi camera (if you have one attached)
Configure gpu memory split under ‘Advanced’. Set it up ‘16’.
Save changes and reboot.
Install required libraries with these commands:

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install build-essential
cmake
gfortran
git
wget
curl
graphicsmagick
libgraphicsmagick1-dev
libatlas-dev
libavcodec-dev
libavformat-dev
libboost-all-dev
libgtk2.0-dev
libjpeg-dev
liblapack-dev
libswscale-dev
pkg-config
python3-dev
python3-numpy
python3-pip
zip
sudo apt-get clean
Install the picamera python library with array support (if you are using a camera):

sudo apt-get install python3-picamera
sudo pip3 install --upgrade picamera[array]
Temporarily enable a larger swap file size (so the dlib compile won’t fail due to limited memory):

sudo nano /etc/dphys-swapfile

< change CONF_SWAPSIZE=100 to CONF_SWAPSIZE=1024 and save / exit nano >

sudo /etc/init.d/dphys-swapfile restart
Download and install dlib v19.6:

mkdir -p dlib
git clone -b ‘v19.6’ --single-branch https://github.com/davisking/dlib.git dlib/
cd ./dlib
sudo python3 setup.py install --compiler-flags “-mfpu=neon”
Install face_recognition:

sudo pip3 install face_recognition
Revert the swap file size change now that dlib is installed:

sudo nano /etc/dphys-swapfile

< change CONF_SWAPSIZE=1024 to CONF_SWAPSIZE=100 and save / exit nano >

sudo /etc/init.d/dphys-swapfile restart
Download the face recognition code examples:

git clone --single-branch https://github.com/ageitgey/face_recognition.git
cd ./face_recognition/examples
python3 facerec_on_raspberry_pi.py
Totally Optional: If you want a desktop GUI, install PIXEL:

sudo apt-get install --no-install-recommends xserver-xorg xinit raspberrypi-ui-mods