I tried installing opencv-contrib-python but I'm unable to get it to work on docker. It says Could not find a version that satisfies the requirement opencv-contrib-python
I tried,
pip install opencv-contrib-python-headless
Then, I tired https://github.com/cassiobotaro/docker-opencv-contrib/blob/master/Dockerfile and I also tried,
FROM python:3.5-alpine COPY . /app WORKDIR /app RUN apk add --no-cache ca-certificates RUN apk add --no-cache git build-base musl-dev alpine-sdk cmake clang clang-dev make gcc g++ libc-dev linux-headers RUN mkdir /tmp/opencv WORKDIR /tmp/opencv RUN wget -O opencv.zip https://github.com/opencv/opencv/archive/3.4.1.zip RUN unzip opencv.zip RUN wget -O opencv_contrib.zip https://github.com/opencv/opencv_contrib/archive/3.4.1.zip RUN unzip opencv_contrib.zip RUN mkdir /tmp/opencv/opencv-3.4.1/build WORKDIR /tmp/opencv/opencv-3.4.1/build RUN cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local -D OPENCV_EXTRA_MODULES_PATH=/tmp/opencv/opencv_contrib-3.4.1/modules -D BUILD_DOCS=OFF BUILD_EXAMPLES=OFF -D BUILD_TESTS=OFF -D BUILD_PERF_TESTS=OFF -D BUILD_opencv_java=OFF -D BUILD_opencv_python=OFF -D BUILD_opencv_python2=OFF -D BUILD_opencv_python3=OFF .. RUN make -j4 RUN make install RUN rm -rf /tmp/opencv RUN pip3 install -r requirements.txt CMD ["app.py"]
But I cannot get either one of it to work. PLease let me know how can I install the above in docker by just the requirements file?
More references (Things that I've tried) : Unable to install/run docker with opencv
and
from .cv2 import * ImportError: libgthread-2.0.so.0: cannot open shared object file: No such file or directory
My guess is that you're seeing the failure on the -alpine version because the opencv package is a binary distribution (it's not just Python code), and it probably hasn't been built for Alpine. Alpine uses a C library that is different from everything else (Alpine uses MUSL libc while just about everthing else uses Glibc); there is some possibility that the opencv codebase won't even build for MUSL. Or maybe it's just that nobody has gotten around to building a binary package. In either case, you're better off with one of the following options:
If I use the stock python:3.5 image (not the Alpine one) it Just Works:
If I use the 3.5-slim tag, I see the same error you reported:
root@63dca11a527f:/# python Python 3.5.5 (default, May 5 2018, 03:17:29) [GCC 4.9.2] on linux Type "help", "copyright", "credits" or "license" for more information. >>> import cv2 Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/usr/local/lib/python3.5/site-packages/cv2/__init__.py", line 3, in <module> from .cv2 import * ImportError: libgthread-2.0.so.0: cannot open shared object file: No such file or directory >>>
As we can see from a package query, that library is owned by the libglib2.0 package, which is apparently not installed by default in the -slim version of the Python image. We can fix that:
# apt-get update # apt-get -y install libglib2.0
And now it runs as expected:
root@63dca11a527f:/# python Python 3.5.5 (default, May 5 2018, 03:17:29) [GCC 4.9.2] on linux Type "help", "copyright", "credits" or "license" for more information. >>> import cv2 >>>
You could build your own image incorporating this fix using a Dockerfile like:
FROM python:3.5-slim RUN apt-get update && apt-get -y install libglib2.0; apt-get clean RUN pip install opencv-contrib-python-headless
Update
Regarding your comment: if you want a package to be available to code running in your container then, yes, you have to install it. Where else will it come from?
If opencv-contrib-python-headless is included in your requirements.txt, then what have posted in the comments should work just fine:
FROM python:3.5 COPY . /app WORKDIR /app RUN pip3 install -r requirements.txt ENTRYPOINT ["python3"] CMD ["app.py"]
If you requirements.txt does not include this (why not?), you would need to explicitly install it:
FROM python:3.5 RUN pip install opencv-contrib-python-headless COPY . /app WORKDIR /app RUN pip3 install -r requirements.txt ENTRYPOINT ["python3"] CMD ["app.py"]
