I was reading this story here in Wired.com about messages embedded in pop albums…
Going through Wired’s list of messages embedded in pop albums, i realized the author’s never heard of the image embedded on Aphex Twin’s track #2 on Windowlicker’s album..
The image can be seen by running the extracted WAV track in a spectrograph program using a logarithmic scale.
Other artists to use hidden images in audio tracks include Venetian Snares, Plaid and others.
more details here