Trouble installing opencv in docker container using pip : <p>I want to build a python docker container that has scikit-learn, opencv, and numpy. Unfortunately, I couldn't find a pre-built container that contained all these, but I did find the one below that contains numpy and scikit-learn.</p>

<p><a href="https://hub.docker.com/r/frolvlad/alpine-python-machinelearning/" rel="noreferrer">https://hub.docker.com/r/frolvlad/alpine-python-machinelearning/</a></p>

<p>I still needed to install opencv, so within my docker file I included a <code>RUN pip install opencv-python</code>. However, I keep on getting the error below: </p>

<p><code>Could not find a version that satisfies the requirement opencv-python (from version: ) 
No matching distribution found for opencv-python</code></p>

<p>Every single thing I have read online says that a <code>pip install opencv-python</code> will work, but it isn't working for me for some reason. Is it a problem with the python package maybe?</p>

<p>Any help is appreciated</p>

<p>Also, I will include my full Dockerfile below, I am aiming to use openFaas, which is a serverless framework, so my Dockerfile might look odd: </p>

<pre><code>FROM frolvlad/alpine-python-machinelearning

RUN apk update
RUN apk upgrade

# Alternatively use ADD https:// (which will not be cached by Docker builder)
RUN apk --no-cache add curl \
    &amp;&amp; echo "Pulling watchdog binary from Github." \
    &amp;&amp; curl -sSL         
https://github.com/openfaas/faas/releases/download/0.8.0/fwatchdog &gt; /usr/bin/fwatchdog \
    &amp;&amp; chmod +x /usr/bin/fwatchdog \
    &amp;&amp; apk del curl --no-cache

# Add non root user
RUN addgroup -S app &amp;&amp; adduser -S -g app app
RUN chown app /home/app

RUN pip install -U pip

USER app

ENV PATH=$PATH:/home/app/.local/bin

WORKDIR /home/app/

RUN pip install opencv-python

RUN mkdir -p function
RUN touch ./function/__init__.py
WORKDIR /home/app/function/
RUN pip install --user app opencv-python

WORKDIR /home/app/
COPY function           function

ENV fprocess="python index.py"

HEALTHCHECK --interval=1s CMD [ -e /tmp/.lock ] || exit 1

CMD ["fwatchdog"]
</code></pre>
