we need wheels for python 3.14, it's falling back to numpy which requires all the tools to compile from source

[Arthurvx]

opencv doesnt work with python 3.14 opencv wheels for python 3.14 opencv update needed opencv numpy

Using cached opencv_python-4.12.0.88-cp37-abi3-win_amd64.whl.metadata (19 kB) Collecting numpy<2.3.0,>=2 (from opencv-python) Using cached numpy-2.2.6.tar.gz (20.3 MB) Installing build dependencies ... done Getting requirements to build wheel ... done Installing backend dependencies ... done Preparing metadata (pyproject.toml) ... error error: subprocess-exited-with-error

× Preparing metadata (pyproject.toml) did not run successfully. │ exit code: 1 ╰─> [21 lines of output] + C:\Users\Arthur\AppData\Local\Programs\Python\Python314\python.exe C:\Users\Arthur\AppData\Local\Temp\pip-install-lo_d4nz9\numpy_5d32a18868064226ad139d5718fc80e4\vendored-meson\meson\meson.py setup C:\Users\Arthur\AppData\Local\Temp\pip-install-lo_d4nz9\numpy_5d32a18868064226ad139d5718fc80e4 C:\Users\Arthur\AppData\Local\Temp\pip-install-lo_d4nz9\numpy_5d32a18868064226ad139d5718fc80e4.mesonpy-u1w001bs -Dbuildtype=release -Db_ndebug=if-release -Db_vscrt=md --native-file=C:\Users\Arthur\AppData\Local\Temp\pip-install-lo_d4nz9\numpy_5d32a18868064226ad139d5718fc80e4.mesonpy-u1w001bs\meson-python-native-file.ini The Meson build system Version: 1.5.2 Source dir: C:\Users\Arthur\AppData\Local\Temp\pip-install-lo_d4nz9\numpy_5d32a18868064226ad139d5718fc80e4 Build dir: C:\Users\Arthur\AppData\Local\Temp\pip-install-lo_d4nz9\numpy_5d32a18868064226ad139d5718fc80e4.mesonpy-u1w001bs Build type: native build Project name: NumPy Project version: 2.2.6 WARNING: Failed to activate VS environment: Could not find C:\Program Files (x86)\Microsoft Visual Studio\Installer\vswhere.exe

  ..\meson.build:1:0: ERROR: Unknown compiler(s): [['icl'], ['cl'], ['cc'], ['gcc'], ['clang'], ['clang-cl'], ['pgcc']]
  The following exception(s) were encountered:
  Running `icl ""` gave "[WinError 2] O sistema não pode encontrar o arquivo especificado"
  Running `cl /?` gave "[WinError 2] O sistema não pode encontrar o arquivo especificado"
  Running `cc --version` gave "[WinError 2] O sistema não pode encontrar o arquivo especificado"
  Running `gcc --version` gave "[WinError 2] O sistema não pode encontrar o arquivo especificado"
  Running `clang --version` gave "[WinError 2] O sistema não pode encontrar o arquivo especificado"
  Running `clang-cl /?` gave "[WinError 2] O sistema não pode encontrar o arquivo especificado"
  Running `pgcc --version` gave "[WinError 2] O sistema não pode encontrar o arquivo especificado"

  A full log can be found at C:\Users\Arthur\AppData\Local\Temp\pip-install-lo_d4nz9\numpy_5d32a18868064226ad139d5718fc80e4\.mesonpy-u1w001bs\meson-logs\meson-log.txt
  [end of output]

note: This error originates from a subprocess, and is likely not a problem with pip. error: metadata-generation-failed

× Encountered error while generating package metadata. ╰─> numpy

note: This is an issue with the package mentioned above, not pip. hint: See above for details.

[lucalista]

Same error on macOS with arm64. As fallback solution, I had to do:

> pip3 install numpy
[ ... and so on, with all dependencies of my project ... ]
> pip3 install opencv-python --no-dep
> pip3 install -e . --no-deps

[Zian]

The workaround for @lucalista didn't exactly work on my Windows computer.

I ran these in a Command Prompt window with administrative rights: python -m pip install numpy python -m pip install opencv-python --no-deps

Later, I was able to run Python as a normal user and "import cv2" without any errors.