Opencv всегда возвращает False в функции cv2.VideoCapture("files/new.mp4")

Собрал докер с ffmpeg и opencv, когда пытаюсь запустить

python3.7 -c 'import cv2; cap = cv2.VideoCapture("files/new.mp4"); print(cap.isOpened());'

Выдает False. Но если на вход даю картинку, вместо видео

python3.7 -c 'import cv2; cap = cv2.VideoCapture("files/img.png"); print(cap.isOpened());'

То выдает размеры картинки и читает её. Как мне сделать так, что бы и видео читало. Код докера ниже:

FROM python:3.7

ENV NVIDIA_VISIBLE_DEVICES all
ENV NVIDIA_DRIVER_CAPABILITIES compute,utility

ENV NUM_CORES 4

RUN apt-get update -y
RUN apt install libgl1-mesa-glx nasm git yasm cmake libtheora-dev opus-tools -y

RUN python3.7 -m pip install --upgrade pip
RUN python3.7 -m pip install opencv-python
RUN python3.7 -m pip install easydict
RUN python3.7 -m pip install firebase_admin
RUN python3.7 -m pip install pyyaml
RUN python3.7 -m pip install tqdm
RUN python3.7 -m pip install google.cloud-storage google-api-python-client google-auth-httplib2 google-auth-oauthlib

WORKDIR /usr/local/src

RUN git clone https://github.com/l-smash/l-smash.git \
    && git clone https://code.videolan.org/videolan/x264.git \
    && git clone https://bitbucket.org/multicoreware/x265_git.git \
    && git clone https://git.ffmpeg.org/ffmpeg.git \
    #&& git clone https://github.com/Itseez/opencv.git \
    #&& git clone https://github.com/Itseez/opencv_contrib.git \
    && git clone --depth 1 git://github.com/mstorsjo/fdk-aac.git \
    && git clone --depth 1 https://chromium.googlesource.com/webm/libvpx \
    && git clone https://github.com/xiph/opus.git

RUN wget https://github.com/opencv/opencv/archive/4.5.1.zip -O opencv.zip --progress=bar:force:noscroll --no-check-certificate && \
    unzip -q opencv.zip && \
    rm opencv.zip && \
    wget https://github.com/opencv/opencv_contrib/archive/4.5.1.zip -O opencv_contrib.zip --progress=bar:force:noscroll --no-check-certificate && \
    unzip -q opencv_contrib.zip && \
    rm opencv_contrib.zip

# Build L-SMASH
# =================================
WORKDIR /usr/local/src/l-smash
RUN ./configure \
    && make -j ${NUM_CORES} \
    && make install
# =================================


# Build libx264
# =================================
WORKDIR /usr/local/src/x264
RUN ./configure --enable-static \
    && make -j ${NUM_CORES} \
    && make install
# =================================


# Build libx265
# =================================
WORKDIR  /usr/local/src/x265_git/build/linux
RUN cmake -DCMAKE_INSTALL_PREFIX:PATH=/usr ../../source \
    && make -j ${NUM_CORES} \
    && make install
# =================================

# Build libfdk-aac
# =================================
WORKDIR /usr/local/src/fdk-aac
RUN autoreconf -fiv \
    && ./configure --disable-shared \
    && make -j ${NUM_CORES} \
    && make install
# =================================

# Build libvpx
# =================================
WORKDIR /usr/local/src/libvpx
RUN ./configure --disable-examples \
    && make -j ${NUM_CORES} \
    && make install
# =================================

# Build libopus
# =================================
WORKDIR /usr/local/src/opus
RUN ./autogen.sh \
    && ./configure --disable-shared \
    && make -j ${NUM_CORES} \
    && make install
# =================================

WORKDIR /usr/local/src
RUN wget -c https://downloads.xiph.org/releases/ogg/libogg-1.3.4.tar.gz && tar zxvf libogg-1.3.4.tar.gz && cd libogg-1.3.4 && ./configure && make -j ${NUM_CORES} && make install && cd ..

WORKDIR /usr/local/src
RUN git clone https://github.com/gypified/libmp3lame.git && cd libmp3lame && ./configure && make -j ${NUM_CORES} && make install

WORKDIR /usr/local/src
RUN wget -c http://downloads.xiph.org/releases/vorbis/libvorbis-1.3.6.tar.gz && tar zxvf libvorbis-1.3.6.tar.gz && cd libvorbis-1.3.6 && ./configure && make -j ${NUM_CORES} && make install && cd ..

# Build OpenCV 3.x
# =================================
#RUN apt-get update -qq && apt-get install -y --force-yes libopencv-dev
RUN python3.7 -m pip install --no-cache-dir --upgrade numpy
WORKDIR /usr/local/src
RUN cd opencv-4.5.1 && mkdir release && cd release && cmake -D CMAKE_BUILD_TYPE=RELEASE \
          -D CMAKE_INSTALL_PREFIX=/usr/local \
          -D WITH_TBB=ON \
          -D BUILD_PYTHON_SUPPORT=ON \
          -D WITH_V4L=ON \
          -D WITH_FFMPEG=ON \
          -D WITH_LIBV4L=ON \
          -D OPENCV_EXTRA_MODULES_PATH=../../opencv_contrib-4.5.1/modules \
          ..

WORKDIR /usr/local/src/opencv-4.5.1/release
RUN make -j ${NUM_CORES} \
    && make install \
    && sh -c 'echo "/usr/local/lib" > /etc/ld.so.conf.d/opencv.conf' \
    && ldconfig


# =================================

# Build ffmpeg.
# =================================
RUN apt-get update -qq && apt-get install -y --force-yes \
    libass-dev



#            --enable-libx265 - Does not work on recent builds
WORKDIR /usr/local/src/ffmpeg
RUN ./configure --extra-libs="-ldl" \
            --enable-gpl \
            --enable-libass \
            --enable-libfdk-aac \
            --enable-libfontconfig \
            --enable-libfreetype \
            --enable-libfribidi \
            --enable-libmp3lame \
            #--enable-libopus \
            --enable-libtheora \
            --enable-libvorbis \
            --enable-libvpx \
            --enable-libx264 \
            --enable-nonfree \
    && make -j ${NUM_CORES} \
    && make install
# =================================


# Remove all tmpfile
# =================================
WORKDIR /usr/local/
RUN rm -rf /usr/local/src
# =================================


RUN python3.7 -m pip install torch==1.7.1+cu110 torchvision==0.8.2+cu110 -f https://download.pytorch.org/whl/torch_stable.html


COPY requirements.txt ./
RUN python3.7 -m pip install -r requirements.txt