There are many programs to conver image to sound:
1) Audio Paint
2) Metasynth
3) Virtual ANS Visual Synthesizer
And the last one, is an i-Phone Application, check on i-Tunes Store:
4) Audible Ink (PocketChirp)
Aphex Twin Used his face's spectrogram to reproduce a sound:

When playing Aphex twin's #2 (the long formula) on their "Windowlicker" album, through a "Spectrogram", an image appears, of what is first thought; a demon!
Aphex Twin is notorious for sneaking in an image of himself in various music videos, CD covers, promotional art, etc. It's a face scary enough to give you nightmares.
