Can not build the project in W11 on ARM64

[alexwan7]

I failed to install the package directly from PIP or manual build.
I found a related issue opened at #644 (comment) from two years ago. I installed all the tools and dependencies mentioned in the comment and repository's Manual Build section. However, I see bunch of error messages related to the cmake building.

I am wondering if ARM64 on W11 is supported? Could you please add the ARM64 on windows wheel to the CI?

[khmyznikov]

Please provide native wheel for WoA. GitHub Actions now supports win-arm64 for free.

Due to the library's popularity, a native version for the growing number of Windows on ARM (WoA) devices offers a better user experience

[khmyznikov]

Latest info about the build process I have:

• VS22 with v143 toolkits. No success.
• VS19 with v142 toolkits. No success. Issue with virtual memory. Couldn't make it work.
• Got back to VS22 to debug those errors. Issues are related to FP16 support or better to say non-support. MSVC++ doesn't support FP16 identifiers used all across opencv-python codebase. Tried replacing them with known data types, but it would take some time considering how deep some of them are inside modules.
• Had to turn off NEON flag. Take a look at the snippet
• After carefully examining all problematic paths, turned out they are related to only two files - Winograd convolution and standard convolution. Both part of so-called DNN module.
• I simply turned DNN modules build off and build it without them.

cmake_args.append("-DBUILD_opencv_dnn=OFF")
cmake_args.append("-DENABLE_NEON=OFF")

[khmyznikov]

related #806

[Avasam]

• I simply turned DNN modules build off and build it without them.

cmake_args.append("-DBUILD_opencv_dnn=OFF")
cmake_args.append("-DENABLE_NEON=OFF")

Thanks!

So in GitHub action, this is how I achieved it:

env:
  # https://github.com/opencv/opencv-python#source-distributions
  # Allows building OpenCV on Windows ARM64
  # https://github.com/opencv/opencv-python/issues/1092#issuecomment-2862538656
  CMAKE_ARGS: "-DBUILD_opencv_dnn=OFF -DENABLE_NEON=OFF"

jobs:
  Build:
    runs-on: windows-11-arm
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-python@v5
        with:
          python-version: 3.13
      - run: pip install opencv-contrib-python-headless