build_wheels_windows.yml

# GitHub Actions Workflow: Build opencv-python with CUDA support on Windows
#
# This workflow compiles opencv-python from source with CUDA enabled on a
# GitHub-hosted Windows runner. The resulting Python wheel is then uploaded
# as a build artifact.
#
# This is a complex and long-running process. It is configured to run only
# on manual trigger (workflow_dispatch).

name: Windows CUDA x64

on:
  workflow_dispatch:


jobs:
  Build:
    runs-on: windows-2025
    strategy:
      fail-fast: false
      matrix:
        python-version: ['3.9']
        platform: [x64]
    env:
      ACTIONS_ALLOW_UNSECURE_COMMANDS: true
      SDIST: 0
      ENABLE_HEADLESS: 0
      ENABLE_CONTRIB: 1
      OPENCV_TEST_DATA_PATH: ${{ github.workspace }}\opencv_extra\testdata
    steps:
    - name: Cleanup
      shell: bash
      run: |
        rm -rf ./* || true
        rm -rf ./.??* || true
      working-directory: ${{ github.workspace }}
    - name: Setup environment
      shell: bash
      run: |
        if [[ "${{ github.event_name }}" == "schedule" || "${{ github.event_name }}" == "workflow_dispatch" ]]; then
          echo "ENABLE_ROLLING=1" >> $GITHUB_ENV
        fi
    - name: Checkout
      uses: actions/checkout@v4
      with:
        submodules: false
        fetch-depth: 0
    - name: Set up Python ${{ matrix.python-version }}
      uses: actions/setup-python@v4
      with:
        python-version: ${{ matrix.python-version }}
        architecture: ${{ matrix.platform }}
    - name: Setup MSBuild.exe
      uses: microsoft/setup-msbuild@v1.1
    - name: Setup NASM
      uses: ilammy/setup-nasm@v1
    - name: Cache CUDA Toolkit Installer
      id: cache-cuda-installer
      uses: actions/cache@v3
      with:
        path: ./.cache/cuda_installer.exe
        key: cuda-installer-12.4.0
    - name: 🔧 Install NVIDIA CUDA Toolkit
      run: |
        $installer_path = "./.cache/cuda_installer.exe"
        if (-not (Test-Path $installer_path)) {
          echo "Downloading CUDA Toolkit..."
          $cuda_installer_url = "https://developer.download.nvidia.com/compute/cuda/12.4.0/network_installers/cuda_12.4.0_windows_network.exe"
          New-Item -Path (Split-Path $installer_path) -ItemType Directory -Force
          curl -L -o $installer_path $cuda_installer_url
        } else {
          echo "CUDA Toolkit installer found in cache."
        }
        echo "Installing CUDA Toolkit silently..."
        $arguments = "-s nvcc_12.4 cudart_12.4 cublas_12.4 cublas_dev_12.4 cufft_12.4 cufft_dev_12.4 npp_12.4 npp_dev_12.4"
        Start-Process -FilePath $installer_path -ArgumentList $arguments -Wait -NoNewWindow
        echo "Adding CUDA to PATH..."
        $CUDA_PATH = "C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v12.4"
        echo "CUDA_PATH=$CUDA_PATH" | Out-File -FilePath $env:GITHUB_ENV -Append
        Copy-Item -Path "$CUDA_PATH/bin/*" -Destination .  -Include "*.dll"
      shell: pwsh
    - name: Cache CuDNN Installer
      id: cache-cudnn-installer
      uses: actions/cache@v3
      with:
        path: ./.cache/cudnn.zip
        key: cudnn-8.9.7.29-cuda-12-windows
    - name: 🔧 Install NVIDIA CuDNN
      run: |
        $cudnn_path = "./.cache/cudnn.zip"
        if (-not (Test-Path $cudnn_path)) {
          echo "Downloading CuDNN..."
          $cudnn_installer_url = "https://developer.download.nvidia.com/compute/cudnn/redist/cudnn/windows-x86_64/cudnn-windows-x86_64-8.9.7.29_cuda12-archive.zip"
          New-Item -Path (Split-Path $cudnn_path) -ItemType Directory -Force
          curl -L -o $cudnn_path $cudnn_installer_url
        } else {
          echo "CuDNN installer found in cache."
        }
        echo "Installing CuDNN..."
        7z x $cudnn_path
        $CUDNN_PATH = "D:/a/opencv-python-cuda/opencv-python-cuda/cudnn-windows-x86_64-8.9.7.29_cuda12-archive"
        echo "CUDNN_LIBRARY=$CUDNN_PATH/lib/x64/cudnn.lib" | Out-File -FilePath $env:GITHUB_ENV -Append
        echo "CUDNN_INCLUDE_DIR=$CUDNN_PATH/include" | Out-File -FilePath $env:GITHUB_ENV -Append
        Copy-Item -Path "$CUDNN_PATH/bin/*" -Destination .  -Include "*.dll"
      shell: pwsh

    - name: Cache build artifacts
      uses: actions/cache@v3
      with:
        path: _skbuild
        key: ${{ runner.os }}-${{ matrix.python-version }}-${{ hashFiles('**/CMakeLists.txt') }}
        restore-keys: |
          ${{ runner.os }}-${{ matrix.python-version }}-
    - name: Build a package
      # CMake 3.25 regression fix. See https://stackoverflow.com/questions/74162633/problem-compiling-from-source-opencv-with-mvsc2019-in-64-bit-version
      run: |
        python --version
        python -m pip install --upgrade pip
        python -m pip install --upgrade setuptools
        python -m pip install cmake==3.24.2
        python -m pip install toml && python -c "import toml; c = toml.load('pyproject.toml'); print('\n'.join(c['build-system']['requires']))" >> requirements.txt | python -m pip install -r requirements.txt
        $CI_BUILD = 1
        if (Test-Path _skbuild) {
          $SKIP_CMAKE = "--skip-cmake"
        }
        python setup.py bdist_wheel --py-limited-api=cp37 --dist-dir="$PWD\wheelhouse" $SKIP_CMAKE -v
      shell: pwsh
    - name: Saving all wheels
      uses: actions/upload-artifact@v4
      with:
        name: wheel-cuda-${{ matrix.platform }}
        path: wheelhouse/opencv*

  Test:
    needs: [Build]
    runs-on: windows-2025
    defaults:
      run:
        shell: cmd
    strategy:
      fail-fast: false
      matrix:
        python-version: ['3.12']
        platform: [x64]
    env:
      ACTIONS_ALLOW_UNSECURE_COMMANDS: true
      OPENCV_TEST_DATA_PATH: ${{ github.workspace }}\opencv_extra\testdata
      PYLINT_TEST_FILE: ${{ github.workspace }}\opencv\samples\python\squares.py
      PlatformToolset: v143
    steps:
    - name: Cleanup
      shell: bash
      run: |
        rm -rf ./* || true
        rm -rf ./.??* || true
      working-directory: ${{ github.workspace }}
    - name: Checkout
      uses: actions/checkout@v4
      with:
        submodules: true
        fetch-depth: 0
    - name: Set up Python ${{ matrix.python-version }}
      uses: actions/setup-python@v4
      with:
        python-version: ${{ matrix.python-version }}
        architecture: ${{ matrix.platform }}
    - name: Download a wheel accordingly to matrix
      uses: actions/download-artifact@v4
      with:
        name: wheel-cuda-${{ matrix.platform }}
        path: wheelhouse/
    - name: Package installation
      run: |
        cd ${{ github.workspace }}/tests
        &python -m pip install --user --no-warn-script-location (ls "../wheelhouse/opencv*.whl")
        if ($LastExitCode -ne 0) {throw $LastExitCode}
        python get_build_info.py
      shell: powershell
    - name: Run tests
      run: |
        cd ${{ github.workspace }}/opencv
        python modules\python\test\test.py -v --repo .
    - name: Pylint test
      run: |
        python -m pip install pylint==2.15.9
        cd ${{ github.workspace }}\tests
        python -m pylint $PYLINT_TEST_FILE