Mplayer volume increasing

Teufel · 11-02-2014, 11:24 PM

I configured my desktop to fire up by RTC. It starts and loads the system. Once system has booted bash script launches mplayer - some kind of alarm clock

The issue is I'd like to get mplayer started not at full load.
I want to increase volume gradually, is it possible to increase volume when mplayer has started already?

eklavya · 11-02-2014, 11:52 PM

If you are playing an audio file using mplayer command, you can set loudness of the sound using -volume parameter.
Now play an mp3 file using

Code:

mplayer -volume 0 /path/of/audio/theme.mp3
and after that
mplayer -volume 150 /path/of/audio/theme.mp3

You can hear the difference.

If you want to increase the volume gradually. Create a loop and increase volume when it plays the file again.

Code:

i=50
while :
do
i=`expr $i + 10`
mplayer -volume $i /path/of/file.mp3
done

It will play the file until you kill the process. You can use `break` to stop playing file if `$i` reaches at it's sufficient value (you can not bear to listen the sound again).

But if your sound is a 5 minute song and you want it should increase the volume gradually for same file not for the loop.
This may be interesting. I do not know if mplayer provides any option like this.

Teufel · 11-03-2014, 04:13 AM

Thanks for reply!

Quote:

Originally Posted by eklavya

But if your sound is a 5 minute song and you want it should increase the volume gradually for same file not for the loop.
This may be interesting. I do not know if mplayer provides any option like this.

Yes, it's exactly what I want to do - increase a volume within a few seconds (10-15 secs)

GazL · 11-03-2014, 04:28 AM

Does it have to be mplayer? The sox suite will do this nicely.
0-100% over 5 seconds:

Code:

play mp3file.mp3 fade 5

Teufel · 11-03-2014, 05:17 AM

Mplayer just ignores "fade". Seems it's impossible for mplayer

Did it for KMix via QDbus. May be it will be interesting for something else:

Code:

#!/bin/bash
for i in `seq 1 33`;
do
    qdbus org.kde.kmix /kmix/KMixWindow/actions/decrease_volume org.qtproject.Qt.QAction.trigger
    sleep 0
done

mplayer /mnt/music/Accept-Predator/Run_Through_The_Night.mp3 -volume 100  > /dev/null 2>&1 &

for i in `seq 1 33`;
do
    qdbus org.kde.kmix /kmix/KMixWindow/actions/increase_volume org.qtproject.Qt.QAction.trigger
    sleep 1
done

script drops volume to zero, starts mplayer and increases volume to 100% within 33 seconds

No need to buy alarm clock

P.S.
Just forgot to mention for GazL: I have no sox installed.

GazL · 11-03-2014, 06:55 AM

Yeah 'fade' is one of the effects sox provides, it won't work on any other command.

You could probably use the lavfi af filter option, something like:

Code:

mplayer -af lavfi=[afade=t=in:ss=0:d=33] file.mp3

The syntax works on 'mpv' (which is what I have installed here), it may be slightly different for original mplayer (which I don't have installed so can't check).

Anyway, if you're happy with your qdbus solution, fair enough. There's more than one way of skinning a cat, as they say.

P.S. 'sox' is quite small and well worth keeping around. Often its much simpler in use than the equivalent mplayer/ffmpeg/libav commands.

Teufel · 11-03-2014, 02:26 PM

Thank you GazL, I think I'll go with mplayer+kmix. I have enough media players installed already

Anyway thanks for your suggestions!