The description on the Vimeo page:
Each note from the instruments is represented by a geometric shape in the animation; while these shapes move in sync with the song, they also form the parts that create the subway itself.
Starting off slowly, with drum-based percussion, followed by layers of synth, guitar, piano, subtle processed vocal effects and even spoken word, suggesting subway passenger chatter, the animation seems to, indeed, follow the composition note-by-note, building in complexity as the music does, from simple shapes to a symphony of lines in motion.
Of particular note to me was the obvious Japanese aesthetic, most noticeable in the black and white palette and the overriding precision of the piece.
The music and the animation are a perfect fit.