random note generator

music.sh

# based on http://blog.robertelder.org/bash-one-liner-compose-music/
# with overflow, channels, timing, etc. bugs fixed

< /dev/urandom hexdump -v -e '/1 "%u\n"' |
gawk 'BEGIN { split("0,2,4,5,7,9,11,12",a,",")}
            { for (i = 0; i < 0.3125; i += 0.0000625)
                printf("%02X\n", 100*sin(1382*exp((a[$1 % 8]/12)*log(2))*i)) }' |
sed -e 's/.*\(..\)$/\1/g' |
xxd -r -p |
sox -traw -c 1 -r16000 -b8 -e signed-integer - -tcoreaudio