osdnk/raspberry-pi-open-cv

raspberry-pi-open-cv

Small program allowing video manipulation using OpenCV along some popular image analyzing techniques.

Made for demonstration of Raspberry Pi possibilities.

Usage

General usage:

python3 record.py --func $FUN --width $WIDTH --height $HEIGHT

For example:

python3 record.py --func gauss-threshold --width 300 --height 400

Parameters

Provide params using --param_name.

fun – function that is applied on captured video data. One of:

• basic-threshold
• gauss-threshold
• sobel-det – sobel edge detection
• laplacian-det – laplacian edge detection
• canny-edge-det – Canny edge detection
• face-recognition – face recognition function
• cartoon
• none – no function is applied on video

Installation on Raspberry Pi 3B+

Installation instructions taking from plain Raspbian to OpenCV-equipped Raspberry. Tested on Raspberry Pi 3B+.

NOTE: you can also run the installation script from install.sh which will do the whole thing automatically.

Preparing the device

Expand filesystem

Make the filesystem take up the whole SD card.

raspi-config --expand-rootfs

Increase swap size

It will be handy for the installation that demands huge amounts of RAM.

export SWAPSIZE=2048

# Stop the swap.
sudo dphys-swapfile swapoff
# Make swap bigger (=> 2048MB).
sed -i "/CONF_SWAPSIZE=.*/CONF_SWAPSIZE=$SWAPSIZE/" /etc/dphys-swapfile
# Create and initialize the swapfile.
dphys-swapfile setup
# Start the swap.
sudo dphys-swapfile swapon

Dependencies

Note: commands are separated as there are layers of dependencies

sudo apt-get update && \
sudo apt-get upgrade && \
sudo apt-get install build-essential cmake pkg-config && \
sudo apt-get install libjpeg-dev libtiff5-dev libjasper-dev libpng12-dev && \
sudo apt-get install libavcodec-dev libavformat-dev libswscale-dev libv4l-dev && \
sudo apt-get install libxvidcore-dev libx264-dev && \
sudo apt-get install libgtk2.0-dev libgtk-3-dev && \
sudo apt-get install libatlas-base-dev gfortran && \
sudo apt-get install python3-dev

Installing OpenCV

Save library version as this appears several times later on.

export VERSION=3.4.3

cd ~
wget -O opencv.zip "https://github.com/Itseez/opencv/archive/$VERSION.zip"
unzip opencv.zip
wget -O opencv_contrib.zip "https://github.com/Itseez/opencv_contrib/archive/$VERSION.zip"
unzip opencv_contrib.zip

Virtual Python environment

sudo pip3 install virtualenv virtualenvwrapper
sudo rm -rf ~/.cache/pip

echo "export WORKON_HOME=$HOME/.virtualenvs" >> ~/.profile
echo "source /usr/local/bin/virtualenvwrapper.sh" >> ~/.profile

source ~/.profile

mkvirtualenv cv -p python3
workon cv

Preparation

pip3 install numpy

cd ~/opencv-$VERSION
mkdir build
cd build

Compiling

cmake \
  -D CMAKE_BUILD_TYPE=RELEASE \
  -D CMAKE_INSTALL_PREFIX=/usr/local \
  -D INSTALL_PYTHON_EXAMPLES=ON \
  -D OPENCV_EXTRA_MODULES_PATH=~/opencv_contrib-$VERSION/modules \
  -D BUILD_EXAMPLES=ON ..

Dis gonna b good

make

Installing

sudo make install
sudo ldconfig

Renaming the library

ls -l /usr/local/lib/python3.5/site-packages
# cv2.cpython-35m-arm-linux-gnueabihf.so -> cv2.so
# export FILENAME=cv2.cpython-35m-arm-linux-gnueabihf.so

cd /usr/local/lib/python3.5/site-packages/
sudo mv $FILENAME cv2.so

cd ~/.virtualenvs/cv/lib/python3.5/site-packages/
ln -s /usr/local/lib/python3.5/site-packages/cv2.so cv2.so

Verification

python3
import cv2
cv2.__version__

Sources

Installing OpenCV 3.4.3 on Raspberry Pi 3 Model B+

Install guide: Raspberry Pi 3 + Raspbian Jessie + OpenCV 3

OpenCV