Create a Command Line Tool using CMake on Windows#

This topic describes the steps needed to configure a CMake project for C++ Command Line Tool. These steps were tested on Windows 11, 23H2. Scripts are PowerShell.

Test that you have all tools installed#

CMake:

cmake --version

ninja:

ninja --version

If you don’t have those tools follow the steps in the Setup C++ development environment on Windows post to configure a C++ development environment.

Create the project directory#

mkdir ~/avblocks/cmake/simple-converter

Create the CMake project#

Switch to the project directory:

cd ~/avblocks/cmake/simple-converter

Add src/main.cpp:

#include <iostream>

int main() {
  std::cout << "Hello AVBlocks!\n";
}

Add CMakeLists.txt:

cmake_minimum_required(VERSION 3.20)

project(simple-converter)

add_executable(simple-converter src/main.cpp)

Add .gitignore:

.cache/
build/

Add build.ps1:

New-Item -Force -Path ./build/debug -ItemType Directory 
Push-Location ./build/debug
    cmake -G 'Ninja' -DCMAKE_BUILD_TYPE=debug ../..
    ninja
Pop-Location

Add configure.ps1:

$tempFile = [IO.Path]::GetTempFileName()

# get the path to Visual Studio 2022
$vs_install_dir = $(Get-VSSetupInstance | Select-VSSetupInstance -Version '[17.0,18.0]' | Select-Object -ExpandProperty InstallationPath)
$vs_common_tools = "${vs_install_dir}/Common7/Tools/"

# run VsDevCmd.bat for x64 C++ compiler and save the environment to a file
cmd /c " `"$vs_common_tools/VsDevCmd.bat`" -arch=amd64 -host_arch=amd64 && set > `"$tempFile`""

# set the environment into PowerShell
Get-Content $tempFile | Foreach-Object {
    if($_ -match "^(.*?)=(.*)$") {
        Set-Content "env:\$($matches[1])" $matches[2]
    }
}

Remove-Item $tempFile

You should end up with the following directory structure:

simple-converter
├── .gitignore
├── CMakeLists.txt
├── build.ps1
├── configure.ps1
└── src
    └── main.cpp

Test the build#

# source configure.ps1
. .\configure.ps1

# build
./build.ps1

Update for AVBlocks#

  1. Download the 64 bit version of AVBlocks for C++ (Windows). The file you need will have a name similar to avblocks-v3.0.1-demo.1-windows.zip except for the version number which may be different.

  2. Extract the archive in a location of your choice, then copy the include and lib directories to the avblocks subdirectory of the CMake project directory. The CMake project directory is the directory that contains the CMakeLists.txt file.

    You should end up with a directory structure similar to the following:

    simple-converter
    ├── .gitignore
    ├── CMakeLists.txt
    ├── avblocks
    │   ├── include
    │   └── lib
    ├── build.ps1
    ├── configure.ps1
    └── src
        └── main.cpp
    
  3. Replace the contents of .gitignore with this code:

    .cache/
    build/
    avblocks/
    
  4. Replace the contents of CMakeLists.txt with this code:

    cmake_minimum_required(VERSION 3.16)
    
    project(simple-converter)
    set (target simple-converter)
    
    add_executable(${target})
    
    # debug definitions
    target_compile_definitions(${target} PRIVATE  _DEBUG)
    
    # debug compile options
    target_compile_options(${target} PRIVATE /Zi /Od)
    
    # enable C++ 17 standard features
    target_compile_features(${target} PRIVATE cxx_std_17)
    
    # include dirs
    target_include_directories(${target} PRIVATE avblocks/include)
    
    # libs
    target_link_directories(${target} PRIVATE avblocks/lib/x64)
    target_link_libraries(${target} AVBlocks64.dll)
    
    # add /MTd or /MT compiler option 
    set_property(TARGET ${target} PROPERTY MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
    
    # sources
    file(GLOB source "src/*.cpp")
    target_sources(${target} PRIVATE ${source})
    
  5. Replace the contents of src/main.cpp with this code:

    #include <primo/avblocks/avb.h>
    #include <primo/platform/reference++.h>
    
    using namespace primo::codecs;
    using namespace primo::avblocks;
    
    int main(int argc, const char * argv[]) {
        // needed for WMV
        CoInitializeEx(nullptr, COINITBASE_MULTITHREADED);
    
        Library::initialize();
    
        auto inputInfo = primo::make_ref(Library::createMediaInfo());
        inputInfo->inputs()->at(0)->setFile(L"Wildlife.wmv");
    
        if (inputInfo->open()) {
            auto inputSocket = primo::make_ref(Library::createMediaSocket(inputInfo.get()));
            auto outputSocket = primo::make_ref(Library::createMediaSocket(Preset::Video::Generic::MP4::Base_H264_AAC));
            outputSocket->setFile(L"Wildlife.mp4");
    
            auto transcoder = primo::make_ref(Library::createTranscoder());
            transcoder->inputs()->add(inputSocket.get());
            transcoder->outputs()->add(outputSocket.get());
    
            if (transcoder->open()) {
                transcoder->run();
                transcoder->close();
            }
        }
    
        Library::shutdown();
    
        CoUninitialize();
    
        return 0;
    }
    
  6. Build the project

    . ./configure.ps1
    ./build.ps1
    

Run the application#

  1. Download the Wildlife.wmv HD movie from the Internet Archive and save it in the project directory.

  2. Copy the file AVBlocks64.dll from avblocks/lib/x64 to build/debug.

  3. Run the application:

    ./build/debug/simple-converter
    

    Wait for the Transcoder to finish - it will take a few seconds. The converted file Wildlife.mp4 will be in the project directory.

Troubleshooting#

  • You may get The program can't start because AVBlocks64.dll is missing from your computer. Try reinstalling the program to fix this problem. or a similar message. To fix that, copy the file AVBlocks64.dll from avblocks/lib/x64 to build/debug.

  • transcoder->open() may fail if there is already a file Wildlife.mp4 in the project directory. Delete Wildlife.mp4 to solve that.