[packman] chromium-ffmpeg-extra in OpenSUSE Tumbleweed: how is libffmpeg.so loaded?

[Dimitrios Apostolou]

Hi Dave, thank you for looking into the issue!

On Sun, 17 Jan 2021, Dave Plater wrote:
>
> I'm not sure which codec is involved in "Microsoft Teams"

Unfortunately I'm not sure either. I get no relevant errors on the
terminal or on the javascript console. But I have seen Teams video calls
working in Chromium in the recent past (a month ago maybe). I suspect the
codec is MPEG-4 ASP because I get "not supported" when I visit on
html5test.com:

MPEG-4 ASP support      No ✘
H.264 support          Yes ✔
H.265 support           No ✘
Ogg Theora support     Yes ✔
WebM with VP8 support  Yes ✔
WebM with VP9 support  Yes ✔

Is anybody getting different results on Chromium?


> but the
> summery for chromium-ffmpeg-extra says "Extra ffmpeg codecs for
> browsers based on Chromium" the actual ffmpeg libraries libavcodec
> libavformat etc are required by chromium itself. If you know the
> specific codec you can find out what your ffmpeg provides with "ffmpeg
> -codecs"

I see a codec listed that can handle MPEG-4 AVC:

  DEV.LS h264                 H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10
(decoders: h264 h264_v4l2m2m h264_qsv h264_cuvid ) (encoders: libx264
libx264rgb h264_nvenc h264_qsv h264_v4l2m2m h264_vaapi nvenc nvenc_h264 )


> if you don't have the packman versions of libavcodec, the
> actual package that Tubleweed chromium uses is libavcodec58_91, then
> this may be your problem.

I just verified that I have it installed from Packman repo, here is what
`zypper search -v` shows:

  i+ | libavcodec58_91                 | package | 4.3.1-9.7  | x86_64 | Packman Repository


What remains as a mystery to me, is how the library
/usr/lib64/chromium-ffmpeg-extra/libffmpeg.so gets loaded by Chromium or
ffmpeg. I have grep'ed or strace'd my whole system with no results. That
path is not listed anywhere. I am starting to believe that this package is
not working any longer.


Thanks,
Dimitris