Simple ANSI terminal K-20 meter[1] for JACK[2].

The averaging meter is a 2nd order filter to emulate a VU meter[3].

The peak is instant-rise and falls linearly at 26 dB / 3 sec.

The over count is the number of overs, where an over is a period of 3 or more
samples at 0dB FS or greater (JACK can have positive dB FS because it's
floating point; 0dB == 1.0).

Hit enter to reset peaks/overs.

-d invokes dump mode, which instead of displaying a meter dumps data to a file
suitable for e.g. gnuplot. See k20.gp for an example plot, i.e.

    k20 -d system:capture_1 > k20.dat
    gnuplot k20.gp

In dump mode, there is no peak falloff (peaks are instantaneous), and values
are plotted once per JACK period.

1. http://www.digido.com/index.php?option=com_content&task=view&id=21&Itemid=2
2. http://jackaudio.org
3. http://tinyurl.com/rmslpf