[FFmpeg-devel] [PATCHv4] ffplay: add support for interactive volume control

Ganesh Ajjanagadde gajjanag at mit.edu
Wed Sep 30 01:50:59 CEST 2015

On Sun, Sep 27, 2015 at 5:09 PM, Marton Balint <cus at passwd.hu> wrote:
> On Sun, 27 Sep 2015, Ganesh Ajjanagadde wrote:
>> This is a feature heavily inspired by the mpv player. At the moment,
>> methods
>> for adjusting volume in ffplay are rather clumsy: either one needs to set
>> it
>> system-wide, or one needs to set it via the volume filter.
>> This patch adds key bindings identical to the mpv defaults for
>> muting/unmuting
>> and increasing/decreasing the volume interactively without any
>> introduction of
>> external dependencies.
>> TODO: doc update, possible mouse button bindings (mpv has this).
>> Signed-off-by: Ganesh Ajjanagadde <gajjanagadde at gmail.com>
>> ---
>> ffplay.c | 36 +++++++++++++++++++++++++++++++++++-
>> 1 file changed, 35 insertions(+), 1 deletion(-)
> Applied, thanks.

BTW, just a heads up: I won't be writing code for mouse wheel
bindings. The reason is that it is more annoying to support:
https://wiki.libsdl.org/MigrationGuide - basically old SDL 1.2 (which
is what many users use) treated it as a button, a mistake corrected in
2.0. I think the code will need to differ accordingly. Thus, configure
will need to export the SDL version, some ifdefry will need to be
done, and all that is gained is a feature which many users in fact
find annoying and explicitly disable:
https://forum.videolan.org/viewtopic.php?f=12&t=108470 (the very first
link in a search for "vlc mouse volume control" :D ).

However, I won't object to a patch as long as it handles both SDL
versions correctly and by default disables mouse volume control.

Another side note on this business: VLC allows "boosting" volume to
125% (I recall even 400% in the past, not sure right now). I regard
this as a misfeature; even their devs later regretted it - maybe
that's why the 400 was toned down to 125. Note that ffplay still
supports such "boosting", but that needs to be done by a -af
volume=+xdB or something like that. I consider it a good thing: if
someone wants something extreme (which can clip the audio), they need
to explicitly enable it via a filter. Thus, I definitely did not
implement this and will object to a modification to ffplay trying to
do such a thing.

I will add a Changelog entry after a week, once bugs/issues with this
(if any) are handled.

> Marton
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel

More information about the ffmpeg-devel mailing list