<img src="https://spectrum.ieee.org/media-library/portrait-of-an-elderly-asian-man-softly-smiling-in-a-suit-jacket-and-tie.jpg?id=67609508&width=1245&height=700&coordinates=0%2C62%2C0%2C63"/><br/><br/><p>Bede Liu, a digital signal processing pioneer, died on 7 May. He was 91.</p><p>Liu was widely re