The sound of pictures...
refreq is a really customable music player. I mean really. You can load music files into refreq, but also images (bitmaps, imgs, pngs). When you load a song, first the program analyzes the track, then it draws its frequency spectrum. After tracking, you can generate the spectral image / bitmap back into music.
At this point, it’s getting really interesting. After you have the image of the track, how you want to play it depends on you, You can play with the timeline, to play the sound from another aspect.