Sanix-Darker / OpenCvCpp-with-Conan

This is a sample project explaining how to use conan in a cpp with an external library such as openCv. and generate a dynamic library in cpp for python

OpenCvCpp with Conan

This is a sample project explaining how to use conan in a cpp with an external library such as openCv.

Requirements

• python (3.x is recommended)
• pip (Install it by running sudo apt-get install python3-pip)
• C++11 (recommended)
• Conan (install it by running pip install conan)
• Boost C++ Python 3.7 (Install it by running : sudo apt-get install cmake libblkid-dev e2fslibs-dev libboost-all-dev libaudit-dev)

Ho to test this project

1- Install pre-requirements

Just run: sh ./shells/install.sh What is done behind the scene:

pip install conan

2- You need to configure your conanfile.txt like this sample:

Sample content :

[requires]
opencv/2.4.13.5@conan/stable

[generators]
cmake

you can also do a conan search your-lib --remote=conan-center and then select in the list what you want to use

3- Config your CMakeLists.txt, conan-packages as follow:

The content of the file :

cmake_minimum_required(VERSION 3.12)

project(opcv)

add_definitions("-std=c++11")
find_package(Boost COMPONENTS python37 REQUIRED)
find_package(PythonInterp 3.7)
find_package(PythonLibs 3.7)

include("./build/conanbuildinfo.cmake")
conan_basic_setup()

add_library(${PROJECT_NAME} 
    SHARED
    module.cpp
    opcv.cpp)

file(
  GLOB
  headers
  *.hpp
)

target_include_directories(${PROJECT_NAME} PRIVATE ${Boost_INCLUDE_DIRS} ${PYTHON_INCLUDE_DIRS})
target_link_libraries(${PROJECT_NAME} ${Boost_LIBRARIES} ${PYTHON_LIBRARIES} ${CONAN_LIBS})

# To build an eecutable
# add_executable(${PROJECT_NAME} opcv.cpp)
target_link_libraries(${PROJECT_NAME} ${CONAN_LIBS})
set_target_properties(${PROJECT_NAME} PROPERTIES PREFIX "")

message("install ${Python_SITELIB}")

Now, we are set-up and we can build our sample app for streaming the camera of our laptop :

4- Check up our code :

Sample code for openCv, this is the tree :

.
├── CMakeLists.txt
├── conanfile.txt
├── MANIFEST.in
├── module.cpp
├── opcv.cpp
├── opcv.hpp
├── README.md
├── setup.py
├── shells
│   ├── build.sh
│   ├── build_whl.sh
│   ├── install_build_start.sh
│   ├── install.sh
│   └── start.sh
├── test.py
├── TO_CREATE_LIB.md
└── WHEN_WAS_NOT_WORKING.md

5- We can now build it to get our .so shared library.

Just run: sh ./shells/build.sh What is done behind the scene:

rm -rf build
mkdir build && cd build
conan install ..
cmake .. -G "Unix Makefiles" -DCMAKE_BUILD_TYPE=Release
cmake --build .

Some files will be added in ./build + the portable of our application in ./build/bin or the lib in ./build/lib :-)

6- if it was an executable we can run our application :

Just run: sh ./start.sh What is done behind the scene:

./build/bin/----

If it was a library we want to call it in our python source code

Just run: sh ./shells/build_whl.sh What is done behind the scene:

pip3 install wheel
pip3 uninstall ./dist/*
rm -rf ./dist/*
python3 setup.py bdist_wheel
pip3 install ./dist/*

In the Cpp sour-code we have :

#include <iostream>
#include "opcv.hpp" 

void printt(std::string strr)
{
    std::cout << "Working Fine!" << std::endl;
    std::cout << "You said : " << strr;
}
.
.
.

We can call it in our python sourcode like this :

from opcv import printt
print(printt("AMAZING !!!"))

Or just run python3 test.py to test it your self.

Output

Author

• Sanix-darker