ModuleNotFoundError: No module named 'mmcv._ext'

[crocis]

When I run app.py I on Ubuntu get the error message ModuleNotFoundError: No module named 'mmcv._ext'

I have tried to install mmcv with pip, mim, and from the source code, but I get the same error message.

I have tested both mmcv version 2.2.0 and 2.0.0

I have installed PyTorch 2.3.0 and CUDA 12.1

This is the list of the installed pip packages
Package Version

---

absl-py 2.1.0
addict 2.4.0
aiofiles 23.2.1
altair 5.3.0
annotated-types 0.6.0
anyio 4.3.0
attrs 23.2.0
av 12.0.0
beautifulsoup4 4.12.3
certifi 2024.2.2
charset-normalizer 3.3.2
click 8.1.7
colorama 0.4.6
contourpy 1.2.1
cycler 0.12.1
exceptiongroup 1.2.1
fastapi 0.110.3
ffmpy 0.3.2
filelock 3.14.0
fonttools 4.51.0
fsspec 2024.3.1
gdown 5.1.0
gitdb 4.0.11
GitPython 3.1.43
gradio 4.28.3
gradio_client 0.16.0
grpcio 1.63.0
h11 0.14.0
h5py 3.11.0
hickle 5.0.3
httpcore 1.0.5
httpx 0.27.0
huggingface-hub 0.23.0
idna 3.7
importlib_metadata 7.1.0
importlib_resources 6.4.0
Jinja2 3.1.3
jsonschema 4.22.0
jsonschema-specifications 2023.12.1
kiwisolver 1.4.5
Markdown 3.6
markdown-it-py 3.0.0
MarkupSafe 2.1.5
matplotlib 3.8.4
mdurl 0.1.2
mmcv 2.2.0
mmengine 0.10.4
model-index 0.1.11
mpmath 1.3.0
networkx 3.3
ninja 1.11.1.1
numpy 1.26.4
nvidia-cublas-cu12 12.1.3.1
nvidia-cuda-cupti-cu12 12.1.105
nvidia-cuda-nvrtc-cu12 12.1.105
nvidia-cuda-runtime-cu12 12.1.105
nvidia-cudnn-cu12 8.9.2.26
nvidia-cufft-cu12 11.0.2.54
nvidia-curand-cu12 10.3.2.106
nvidia-cusolver-cu12 11.4.5.107
nvidia-cusparse-cu12 12.1.0.106
nvidia-nccl-cu12 2.20.5
nvidia-nvjitlink-cu12 12.4.127
nvidia-nvtx-cu12 12.1.105
opencv-python 4.9.0.80
opendatalab 0.0.10
openmim 0.3.9
openxlab 0.0.11
ordered-set 4.1.0
orjson 3.10.2
packaging 24.0
pandas 2.2.2
pillow 10.3.0
pip 24.0
platformdirs 4.2.1
progressbar2 4.4.2
protobuf 5.26.1
psutil 5.9.8
pycryptodome 3.20.0
pydantic 2.7.1
pydantic_core 2.18.2
pydub 0.25.1
Pygments 2.17.2
pyparsing 3.1.2
PySocks 1.7.1
python-dateutil 2.9.0.post0
python-multipart 0.0.9
python-utils 3.8.2
pytz 2024.1
PyYAML 6.0.1
referencing 0.35.1
requests 2.31.0
rich 13.7.1
rpds-py 0.18.0
ruff 0.4.2
segment_anything 1.0
semantic-version 2.10.0
setuptools 59.6.0
shellingham 1.5.4
six 1.16.0
smmap 5.0.1
sniffio 1.3.1
soupsieve 2.5
starlette 0.37.2
sympy 1.12
tabulate 0.9.0
tensorboard 2.16.2
tensorboard-data-server 0.7.2
termcolor 2.4.0
thinplate 1.0.0
tomli 2.0.1
tomlkit 0.12.0
toolz 0.12.1
torch 2.3.0
torchvision 0.18.0
tqdm 4.66.2
triton 2.3.0
typer 0.12.3
typing_extensions 4.11.0
tzdata 2024.1
urllib3 2.2.1
uvicorn 0.29.0
websockets 11.0.3
Werkzeug 3.0.2
yapf 0.40.2
zipp 3.18.1

[jp-schneider]

Hey @crocis,

I got the same issue as you did. I solved it using a version of mmcv which matches the pytorch version and cuda release.
There is currently no build of mmcv for the pytorch version 2.3 so you would need 2.2.

You should be able to solve this by uninstalling you current version of mmcv and torch and reinstall them using a matching index:

pip uninstall mmcv torch torchvision torchaudio
pip install torch torchvision torchaudio --index-url https://download.pytorch.org/whl/cu121
pip install mmcv==2.2.0 -f https://download.openmmlab.com/mmcv/dist/cu121/torch2.2/index.html

Hope that helps!

[mteixeiraTecgraf]

For me it appears to be missing cuda and MSVC problems with compiler cl.exe.

I fixed the problem after reinstalling CUDA and Microsoft Visual Studio.

Could not resolve MSVC cl.exe problem on CONDA Environment.