 In order to perfectly match the singing with the movements of the actors' lips on the screen, he transcribed all the lines and meticulously located them so that the music perfectly matched the image.Glass thus timed each word of the film's dialogues by electronic tracking of the film and placed them mathematically in the score, then synchronized music and film using a computer which, in charge of sorting the delays and advances of the spoken and sung words, recalculated the digital signals of the audio tape on the film's digital circuit.A stage production requires three different levels