midi to control volume, change title in amarok

[spm_gl]

Why would you want to control jack?

Simple, my controller has a wonderful shuttle wheel, which doensn't work in ardour, but now I can smoothly scroll the timeline of all jack-transport enabled programs (especially xjadeo) together, which is perfect for video sync work.

[raboof]

Why would you want to control jack?

Simple, my controller has a wonderful shuttle wheel, which doensn't work in ardour, but now I can smoothly scroll the timeline of all jack-transport enabled programs (especially xjadeo) together, which is perfect for video sync work.

Oh yes, jack transport is definitely useful - for a moment i thought you wanted to use it for controlling amarok.

[raboof]

I found 'aseqdump' for dumping ALSA midi data to stdout. With that, it's quite easy to whip together a small script that translates midi events into qdbus calls

Hmm, I found out that on some systems, this would introduce some unwanted buffering. The following version solves this, and requires aseqdump and IO::Pty (packaged as libio-pty-perl on debian):

Code: Select all

#!/usr/bin/perl

use strict;

use IO::Pty;
use IPC::Open2;

my $pty = IO::Pty->new;
open2(">&" . fileno($pty), my $in, "aseqdump");
my $s = $pty->slave;

while (<$s>)
{
        print $_;
        if ($_ =~ /controller 7, value (\d+)/)
        {
                my $ccValue = $1;
                my $volume = int($ccValue * 100 / 127);
                print "Setting volume to $volume\n";
                `qdbus org.kde.amarok /Player VolumeSet $volume`
        }
}

.. then start it with:

Code: Select all

./scriptfilename.pl