使用 OpenCV 进行运动检测

$ sudo apt-get install libjpeg-dev libpng-dev libtiff-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 libgtk-3-dev 
$ sudo apt-get install libcanberra-gtk*

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

$ sudo apt-get install python3.7-dev
After installing to check if the dev files are installed in correct directory check using this command
$ python3.7-config --includes
-I/usr/include/python3.7m -I/usr/include/python3.7m
The first path is expected and second is current path. 
If they are not the same then you need to perform a copy command to change the current path
$ sudo cp /current/path/to/dev/file/pyconfig.h /usr/include/python3.7m
pyconfig.h is the dev file that you need to copy to correct directory

$ sudo apt-get install python3-pip
If this won't work then use the following commands
$ wget https://bootstrap.pypa.io/get-pip.py
$ sudo python3 get-pip.py
$ sudo apt autoremove
If pip is already installed then make sure it's the latest version 
$ pip --version
If not then - 
$ pip install --upgrade pip

$ sudo pip install virtualenv virtualenvwrapper
$ sudo rm -rf ~/get-pip.py ~/.cache/pip
Update .bashrc to finish installing the tools, use nano or similar text editor - 
# virtualenv and virtualenvwrapper
export WORKON_HOME=$HOME/.virtualenvs
export VIRTUALENVWRAPPER_PYTHON=/usr/bin/python3
source /usr/local/bin/virtualenvwrapper.sh
save and exit
And finally create the virtual environment- 
$ mkvirtualenv cv -p python3
Verify if cv environment is working or not - 
$ workon cv
(cv) pi@raspberrypi:~$
(cv) indicates that we are inside a virtual environment

Install Numpy
$ pip install numpy
Install imutils
$ pip install imutils

$ sudo nano /etc/dphys-swapfile
Edit CONF_SWAPSIZE as
CONF_SWAPSIZE=2048

$ free -m
$ swapon -s

$ pip install opencv-python
$ pip install opencv-contrib-python    // Ref.