2 Scriptable tone detection and audio analysis
7 * Does all the dirty work using Goertzel algorithm
8 * http://en.wikipedia.org/wiki/Goertzel_algorithm
9 * Detect specified tones and print their levels
10 * Filter tones using tresholds
11 * Eg.: Print levels only when treshold is crossed (=event detection)
15 * Sample scripts using goertzel.c
16 * **dtmf.sh**: decodes DTMF signals in audio
17 * **histogram.pl**: shows goertzel output in ASCII graphs
18 * **histogram.sh**: example using histogram.pl to draw realtime equalizer
19 * **sleepmon.sh**: Generates frequency on soundcard output and detects it on input
20 * Can be used to detect and log motion using soundcard and PIR sensor or NC switch
21 * **sleepplot.sh*: Generates gnuplot graph from sleeplog