Bede Liu, a digital signal processing pioneer, died on 7 May at age 91. The IEEE Life Fellow taught electrical engineering at Princeton for more than 50 years and chaired its electrical and computer engineering department from 1994 to 1997. His research aided the transition from analog to digital processing of sound, images, and video, establishing mathematical techniques that underpin modern communications, multimedia systems, and consumer electronics. Low-power digital signal processors enabling cellphone calls, streaming video, and Internet communications trace to his 1970s and ’80s work.

Liu earned his bachelor’s from National Taiwan University in 1954, master’s from the Polytechnic Institute of Brooklyn in 1956, and doctorate in 1960. After a Bell Labs fellowship, he joined Princeton in 1962. With Abe Peled, he authored the 1976 textbook *Digital Signal Processing: Theory, Design, and Implementation*, published 250 technical papers, and held 12 U.S. patents. He advised 53 doctoral students, including Robert Kahn, who helped create the modern Internet architecture.

In the 2000s, Liu focused on media integrity and digital watermarking, co-authoring *Multimedia Data Hiding* with former student Min Wu. An active IEEE volunteer, he served on the IEEE Board of Directors and as president of the IEEE Circuits and Systems Society. Colleagues remember his humility, humor, and encouragement of ambitious, unconventional projects.