The *.wav files in this directory contain a human voice speaking each
of the 16 hexadecimal digits.  If a captcha string consists of just
hexadecimal digits (as is the case for captchas generated by the
[../captcha.c module](../captcha.c)) then these WAV files can be
concatenated together to generate an audio reading of the captcha, which
enables visually impaired users to complete the captcha.

Each of the WAV files uses 8000 samples per second, 8 bytes per sample
and are 6000 samples in length.

The recordings are made by Philip Bennefall and are of his own voice.
Mr. Bennefall is himself blind and uses this system implemented with these
recordings to complete captchas for Fossil.
