The image is using two color channels, one red and one green. The red one is slightly different from the green one.
I modified a few things and made 3 images, one that uses the red channel, one that uses the green channel and another one that uses the red channel and the image from the green channel on the blue channel. The last image is able to be transformed into a stereo sound file, but it doesn't make much difference. I also transformed them into sound files using Bitmaps & Waves with the following configurations: Block size 512, Range 60, Sampling 44100 and Transpose 0. The single channel audio files has less noise
http://www.megaupload.com/?d=56DABTYD