Linux build and install

Follow a video session for building C++ and python on Pi

Build dependencies

Make sure these are installed first and that their executables are in your path:

  • cmake - should already be installed since you built OpenCV by yourself.
  • git (optional) - you can also download the sources from GitHub.
  • swig (optional) - needed for building the python extension.

Prepare to build

git clone https://github.com/sagi-z/BackgroundSubtractorCNT.git --single-branch
cd BackgroundSubtractorCNT
mkdir build
cd build

By default cmake is building for release, static lib, without the C++ demo and without the python extension

cmake ..
make

Here is how to alter the defaults

cmake -DBUILD_TEST=ON -DBUILD_SHARED_LIBS=ON -DPYTHON_EXTENSION=ON -DCMAKE_BUILD_TYPE=DEBUG ..
make

(note that these are now the new defaults until you delete the build/CMakeCache.txt file)

Here is how to build for a specific python interpreter

cmake -DPYTHON_EXTENSION=ON -DPYTHON=/usr/bin/python3.5 ..
make

(note that these are now the new defaults until you delete the build/CMakeCache.txt file)

C++ Install simplest option 1 (Win/Linux/Mac):

copy/move the bgsubcnt.cpp to your sources and bgsubcnt.h to your headers.

C++/Python Install option 1 for Linux (from the build directory):

sudo make install

C++/Python Install option 2 for Linux - cleaner (from the build directory):

cpack -G DEB
sudo dpkg -i ./bgsubcnt-1.1.3-Linux.deb

Windows build and install

Follow a video session for building C++ and python on windows

Build dependencies

Make sure these are installed first and that their executables are in your path:

  • cmake - should already be installed if you built OpenCV by yourself (configure OPENCV_DIR as required for build using OpenCV with cmake).
  • Visual Studio - a C++ compiler - I’m using Visual Studio 2015.
  • git (optional) - you can also download the sources from GitHub.
  • swig (optional) - needed for building the python extension.
  • NSIS (optional) - if you want to build a package installer.
  • Python (optional) - if you want to build the python extension.
  • Python compiler for your python version (optional) - needed for building the python extension (i.e. for python2.7 you need to install Microsoft Visual C++ 2008 Express Edition).

Building

  • This should be done from a “Developer Command Prompt for VS2015” (Open it from the Start menu):
REM check dependencies are in path/exist
REM ====================================
cd c:\users\sagiz
where git
where swig
where cmake
echo %OPENCV_DIR%
where msbuild
where python
dir "c:\Program Files (x86)\NSIS\NSIS.exe"

REM get the sources
REM ===============
cd c:\users\sagiz
git clone https://github.com/sagi-z/BackgroundSubtractorCNT.git --single-branch
cd BackgroundSubtractorCNT
mkdir build
cd build

REM configure the build
REM ===================
cmake -G "Visual Studio 14 2015 Win64" -DBUILD_TEST=ON -DPYTHON_EXTENSION=ON ..

REM build the sources
REM =================
msbuild ALL_BUILD.vcxproj /p:Configuration=Release

REM build the installer
REM ===================
msbuild PACKAGE.vcxproj

REM run the installer
REM =================
.\bgsubcnt-1.1.3-win64.exe /p:Configuration=Release

REM check if we can load the module
REM ===============================
set PYTHONPATH=C:\Program Files\bgsubcnt 1.1.3\lib\site-packages
cd ..
python -c "import cv2, bgsubcnt; fgbg = bgsubcnt.createBackgroundSubtractor(); print fgbg"

  • Here is an example command line session in a “Developer Command Prompt for VS2015” with outputs:
REM check dependencies are in path/exist
REM ====================================
c:\Users\sagiz>where git
C:\Program Files\Git\cmd\git.exe

c:\Users\sagiz>where swig
C:\swigwin-3.0.10\swig.exe

c:\Users\sagiz>where cmake
C:\Program Files\CMake\bin\cmake.exe

c:\Users\sagiz>echo %OPENCV_DIR%
C:\opencv-3.1.0\build

c:\Users\sagiz>dir %OPENCV_DIR%
 Volume in drive C has no label.
 Volume Serial Number is 6431-83A8

 Directory of C:\opencv-3.1.0\build

12/24/2016  05:08 PM    <DIR>          .
12/24/2016  05:08 PM    <DIR>          ..
12/18/2015  05:15 PM    <DIR>          bin
12/18/2015  05:15 PM    <DIR>          etc
12/18/2015  05:15 PM    <DIR>          include
12/18/2015  05:13 PM    <DIR>          java
12/18/2015  03:16 PM             2,224 LICENSE
12/18/2015  05:10 PM               433 OpenCVConfig-version.cmake
12/18/2015  03:16 PM             6,916 OpenCVConfig.cmake
12/18/2015  05:15 PM    <DIR>          python
12/24/2016  05:07 PM    <DIR>          x64
               3 File(s)          9,573 bytes
               8 Dir(s)  14,000,812,032 bytes free

c:\Users\sagiz>where msbuild
C:\Program Files (x86)\MSBuild\14.0\Bin\MSBuild.exe
C:\Windows\Microsoft.NET\Framework\v4.0.30319\MSBuild.exe

c:\Users\sagiz>where python
C:\Python27\python.exe

c:\Users\sagiz>dir "c:\Program Files (x86)\NSIS\NSIS.exe"
 Volume in drive C has no label.
 Volume Serial Number is 6431-83A8

 Directory of c:\Program Files (x86)\NSIS

12/11/2016  11:50 PM         1,026,048 NSIS.exe
               1 File(s)      1,026,048 bytes
               0 Dir(s)  14,001,606,656 bytes free

REM get the sources
REM ===============
c:\Users\sagiz>git clone https://github.com/sagi-z/BackgroundSubtractorCNT.git --single-branch
Cloning into 'BackgroundSubtractorCNT'...
… (didn’t copy-paste all the output lines)...

c:\Users\sagiz>cd BackgroundSubtractorCNT

c:\Users\sagiz\BackgroundSubtractorCNT>mkdir build

c:\Users\sagiz\BackgroundSubtractorCNT>cd build


REM configure the build
REM ===================
c:\Users\sagiz\BackgroundSubtractorCNT\build>cmake -G "Visual Studio 14 2015 Win64" -DBUILD_TEST=ON -DPYTHON_EXTENSION=ON ..
… (didn’t copy-paste all the output lines). ..
-- Configuring done
-- Generating done
-- Build files have been written to: C:/Users/sagiz/BackgroundSubtractorCNT/build

REM build the sources
REM =================
c:\Users\sagiz\BackgroundSubtractorCNT\build>msbuild ALL_BUILD.vcxproj /p:Configuration=Release
… (didn’t copy-paste all the output lines). ..
    0 Error(s)

Time Elapsed 00:00:08.51

REM build the installer
REM ===================
c:\Users\sagiz\BackgroundSubtractorCNT\build>msbuild PACKAGE.vcxproj /p:Configuration=Release
… (didn’t copy-paste all the output lines). ..
Build succeeded.
    0 Warning(s)
    0 Error(s)

Time Elapsed 00:00:13.33

REM run the installer
REM =================
c:\Users\sagiz\BackgroundSubtractorCNT\build>.\bgsubcnt-1.1.3-win64.exe

REM check if we can load the module
REM ===============================
c:\Users\sagiz\BackgroundSubtractorCNT\build>set PYTHONPATH=C:\Program Files\bgsubcnt 1.1.3\lib\site-packages

c:\Users\sagiz\BackgroundSubtractorCNT\build>cd ..

c:\Users\sagiz\BackgroundSubtractorCNT>python -c "import cv2, bgsubcnt; fgbg = bgsubcnt.createBackgroundSubtractor(); print fgbg"
<Swig Object of type 'BackgroundSubtractorCNT *' at 0x0000000003891110>

Install

Update/add the environment variable PYTHONPATH to point to where the python extension was installed (in the example above it was added to C:\Program Files\bgsubcnt 1.1.3\lib\site-packages). In the File Explorer, right-click on This PC and coose properties. Then choose Advanced system settings and press the “Environment Variables …” button.

C++ Usage

Linux

Assuming installation in ‘/usr/local’, add to cflags ‘-I/usr/local/include’ and to link flags ‘-L/usr/local/lib -lbgsubcnt’

Here is a minimal CMakeLists.txt example:

CMAKE_MINIMUM_REQUIRED(VERSION 2.8)

PROJECT(myapp)

FIND_PACKAGE(OpenCV 3.1.0 REQUIRED)

INCLUDE_DIRECTORIES(${OpenCV_INCLUDE_DIRS} "/usr/local/include")

ADD_EXECUTABLE(myapp main.cpp)

FIND_LIBRARY(BGSUBCNT_LIB bgsubcnt "/usr/local/lib")
TARGET_LINK_LIBRARIES (myapp ${BGSUBCNT_LIB} ${OpenCV_LIBS})

Windows

make sure the include path and link path and library are set correctly.

C++ drop in replacement code example:

// Example from main.cpp, which is built if you supply -DBUILD_TEST=ON to cmake
#include <opencv2/opencv.hpp>
#include "bgsubcnt.h"
...

    string type = parser.get<string>("type"); // get the BackgroundSubtractor type somehow

    cv::Ptr<cv::BackgroundSubtractor> pBgSub; // THE SAME BASE CLASS

    if (type == "CNT")
    {
        int fps = 15;
        if (hasFile)
        {
            fps = capture.get(CAP_PROP_FPS);
        }
        pBgSub = cv::bgsubcnt::createBackgroundSubtractorCNT(fps, true, fps*60);
    }
    else if (type == "MOG2")
    {
        cv::Ptr<cv::BackgroundSubtractorMOG2> pBgSubMOG2 = cv::createBackgroundSubtractorMOG2();
        pBgSubMOG2->setDetectShadows(false);
        pBgSub = pBgSubMOG2;
    }

...

    // THIS CODE DOESN'T CHANGE
    for(;;)
    {
        cv::Mat frame;
        cap >> frame;
        if( frame.empty() )
        {
            break;
        }
        cv::Mat gray;
        cv::cvtColor(frame, gray, cv::COLOR_BGR2GRAY);

        cv::Mat fgMask;
        pBgSub->apply(gray, fgMask);
...
    }

Python Usage

import bgsubcnt                               # 1. New import
fgbg = bgsubcnt.createBackgroundSubtractor()  # 2. New background subtractor

Python drop in replacement code example:

import numpy as np
import cv2
import bgsubcnt                               # 1. New import

# A temporary solution to OpenCV 3.1.0 bug
#  with background subtractors
cv2.ocl.setUseOpenCL(False)

cap = cv2.VideoCapture('/home/userName/Downloads/opencv-3.1.0/samples/data/768x576.avi')

#fgbg = cv2.createBackgroundSubtractorMOG2()
fgbg = bgsubcnt.createBackgroundSubtractor()  # 2. New background subtractor

while(1):
    ret, frame = cap.read()
    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)

    fgmask = fgbg.apply(gray)

    cv2.imshow('frame',fgmask)
    k = cv2.waitKey(30)
    if k == 27:
        break

cap.release()
cv2.destroyAllWindows()

Using the C++ demo (from the ‘build’ directory)

  • help message
    pi@pilab2:~/tmp/mnt/build_pi3 $ ./demo -h
    BackgroundSubtractorCNT demo/benchmark/comparison
    Usage: demo [params] 
    
      -?, -h, --help, --usage (value:true)
          print this message
      --bg
          calculate also the background
      --file
          use file (default is system camera)
      --nogui
          run without GUI to measure times
      --type (value:CNT)
          bg subtraction type from - CNT/MOG2/KNN
    
  • For benchmarking, use ‘-nogui’, this was executed on Raspberry Pi3:
    pi@pilab2:~/tmp/mnt/build_pi3 $ ./demo -file=/home/pi/tmp/mnt2/samples/data/768x576.avi -nogui -type="MOG2"
    Execution took 40.964450 seconds.
    pi@pilab2:~/tmp/mnt/build_pi3 $ ./demo -file=/home/pi/tmp/mnt2/samples/data/768x576.avi -nogui -type="CNT"
    Execution took 17.633301 seconds.
    
  • For seeing the ‘fg’ quality use these:
    ./demo -file=/home/pi/tmp/mnt2/samples/data/768x576.avi -type="CNT"
    
  • For seeing the ‘fg’ and ‘bg’ quality use these:
    ./demo -file=/home/pi/tmp/mnt2/samples/data/768x576.avi -type="CNT" -bg
    

Using the python demo (from the ‘python’ directory)

  • help message
    pi@pilab2:~/BackgroundSubtractorCNT $ python python/demo.py -h
    BackgroundSubtractorCNT demo/benchmark/comparison
    Usage: demo.py [params] 
    
      -h, --help
          print this message
          --bg    
          calculate also the background
      --file
          use file (default is system camera)
      --nogui 
          run without GUI to measure times
      --type (default:CNT)
          bg subtraction type from - CNT/MOG2/KNN
    
  • For benchmarking, use ‘–nogui’, this was executed on Raspberry Pi3:
    pi@pilab2:~/BackgroundSubtractorCNT $ python python/demo.py --file=/home/pi/tmp/mnt2/samples/data/768x576.avi --nogui --type="MOG2"
    Execution took 40.964450 seconds.
    pi@pilab2:~/BackgroundSubtractorCNT $ python python/demo --file=/home/pi/tmp/mnt2/samples/data/768x576.avi --nogui --type="CNT"
    Execution took 17.633301 seconds.
    
  • For seeing the ‘fg’ quality use these:
    python demo.py --file=/home/pi/tmp/mnt2/samples/data/768x576.avi --type="CNT"
    
  • For seeing the ‘fg’ and ‘bg’ quality use these:
    python demo.py --file=/home/pi/tmp/mnt2/samples/data/768x576.avi --type="CNT" --bg