Did you validate that scripts which use this containers are not broken by this patch?

Did you validate that scripts which use this containers are not broken by this patch?

build is still pending , i think needed some approval .

From my side , this is apt-get package install optimization , this tweak doesn't let install unnecessary packages or recommended packages in simple straight forward way

install unnecessary packages or recommended packages

But these packages can be used by dependent scripts, so patch should be validated.

Unfortunately, there are no automatic tests on this stuff (it just a sample, no frequent updates are expected). So it requires manual validation on local machines.

By default, Ubuntu or Debian based "apt" or "apt-get" system installs recommended but not suggested packages .

By passing "--no-install-recommends" option, the user lets apt-get know not to consider recommended packages as a dependency to install.

This results in smaller downloads and installation of packages .

Refer to blog at Ubuntu Blog .

results in smaller image size.

Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

• I agree to contribute to the project under OpenCV (BSD) License.
• To the best of my knowledge, the proposed patch is not based on a code under GPL or other license that is incompatible with OpenCV
• The PR is proposed to proper branch
• There is reference to original bug report and related work
• There is accuracy test, performance test and test data in opencv_extra repository, if applicable
  Patch to opencv_extra has the same branch name.
• The feature is well documented and sample code can be built with the project CMake

As i mentioned and refered to the blog also . In general any apt package installation consist there a list of their main dependencies beside that there are some suggested packages , which "--no-install-recommends" prevent them from installing

@alalek It looks like the change does not introduce regressions.
Command: ./build_plugins.sh ./tmp/
Output:

libopencv_videoio_ffmpeg_shared_2.8.15.so
libopencv_videoio_ffmpeg_shared_4.1.so 
libopencv_videoio_ffmpeg_static_3.4.5.so
libopencv_videoio_ffmpeg_ubuntu_16.04.so
libopencv_videoio_gstreamer.so
libopencv_videoio_ffmpeg_shared_3.4.5.so
libopencv_videoio_ffmpeg_static_2.8.15.so
libopencv_videoio_ffmpeg_static_4.1.so
libopencv_videoio_ffmpeg_ubuntu_18.04.so

👍