Docker-stacks: Following Debian upstream in adopting ffmeg over libav-tools

[taqtiqa-mark]

Hi! Thanks for all the effort making Jupyter's docker-stacks images.

libav-tools (jupyter/scipy-notebook)

I'm porting the Jupyter stacks to Apline Linux containers. As part of that, while building jupyter/scipy-notebook I discovered libav is not available on Alpine Linux, but ffmeg is. The libav team was not very responsive/proactive about the patch to try make it work, and things seem to have stalled. I don't see any evidence to expect this to change.

On further digging I discovered that, unfortunately, there has been some ping-pong in Debian around libav vs ffmeg.
Having dropped ffmeg at one point they seem now to have now dropped libav and picked ffmpeg back up.
Previously this affected this project per issue #90, where ffmpeg was not available in a ubuntu distribution.
Some detail behind the change is set out in a LWN article. It seems the reasons (security) for switching back to ffmeg are not trivial. The announcement is here

Any chance you'd consider following upstream and using ffmpeg in place of libav-tools?

If not that is fine, I will just need to include a notice in the README.md.

[parente]

Previously this affected this project per issue #90, where ffmpeg was not available in a ubuntu distribution.

I believe the images here were based on Debian Jessie at the time. Now they derive from Ubuntu 16.04, so switching to ffmpeg shouldn't be all that difficult. If you'd like to submit a PR with the change, along with a notebook showing that matplotlib animation still works properly, I think we can merge it.

[jakirkham]

There’s also ffmpeg in conda-forge, which could be used to this end.

[taqtiqa-mark]

Unfortunately, I'm going to have to leave this to someone else. The Alpine build is taking all my spare cycles. I'll try to remember to report any issues I encounter over here, in case it helps you ease the transition.

I'll go ahead and use ffmpeg with the hope/expectation that at some point the switch from libav-tools will be made.

Happy for you to close this or leave it open. As you wish.

[parente]

No problem, @taqtiqa-mark. Please leave the issue open.

[jakirkham]

If it's any help, I use ffmpeg from conda-forge to generate videos either with matplotlib or moviepy (primarily on our Linux-based cluster). Don't know what bar you had in mind for testing, but maybe that provides some assurance that this does work.

[Bidek56]

I have attempted to build the stack using Ubuntu 18.04 but Mesos is not available for 18.04 yet.
I should be available in few weeks according to the forum.

[parente]

This was closed by #641. The images now include ffmpeg instead of libav-tools.