Bede Liu, a digital signal processing pioneer, died on 7 Might. He was 91.
Liu was extensively thought to be one of many founders of contemporary digital signal processing, a subject that applies mathematical algorithms to investigate, modify, and transmit alerts together with sound, pictures, and video.
The IEEE Life Fellow taught electrical engineering at Princeton for greater than 50 years. From 1994 to 1997, he chaired the college’s electrical and computer engineering department.
Liu’s analysis aided the transition from analog to digital processing of sound, pictures, and video. His work helped set up lots of the mathematical and engineering methods that underpin trendy communications, multimedia methods, and consumer electronics.
Though little identified exterior engineering circles, his work is embedded in applied sciences utilized by billions of individuals. The low-power digital sign processors that make cellphone calls, streaming video, and Web communications doable may be traced to analysis he carried out within the Nineteen Seventies and ‘80s.
Liu acquired the 2018 IEEE Jack S. Kilby Signal Processing Medal for “sustained contributions to the evaluation and the event of low-complexity realizations of digital sign processing algorithms.”
“We stream music and video. We take pictures with our telephones, and we ship them round. We don’t even give it some thought,” IEEE Life Fellow H. Vincent Poor mentioned in an obituary for Liu. “Nevertheless it’s all due to the sign processing, image processing, and video processing that’s been developed over time, in addition to different applied sciences which have grown up beside it and enabled it, like semiconductors. The event of those processing advances was precisely what Bede was a serious a part of.” Poor is a professor {of electrical} and computer engineering at Princeton.
An impactful scholar and instructor
Liu was born in Shanghai in 1934. Throughout his childhood, his household relocated to Taiwan amid the upheaval of the Chinese Civil War. His father, Henry Liu Sr., was {an electrical} engineer.
Liu earned his bachelor’s diploma in electrical engineering in 1954 from the National Taiwan University, in Taipei. After graduating, he and his household moved to the United States. Liu and his father attended the Polytechnic Institute of Brooklyn (now the New York University Tandon School of Engineering) collectively. They earned their grasp’s levels in electrical engineering in 1956. Liu continued his research on the faculty, incomes a doctoral diploma in electrical engineering 4 years later.
In 1959 he was awarded a Bell Labs fellowship and labored on the firm’s Murray Hill, N.J., location till he joined Princeton in 1962.
“Liu was a extremely impactful scholar and instructor—at all times pondering forward of future wants and altering applied sciences,” mentioned IEEE Life Fellow Peter J. Ramadge, a Princeton professor emeritus of engineering.
Cellphones make use of a substantial quantity of digital sign processing, Liu as soon as famous. Most of the subject’s advances, he added, concerned making refined processing sensible on gadgets with restricted computing energy—which is the problem that confronted generations of engineers designing moveable electronics.
Liu’s analysis contributions helped form each the speculation and follow of digital sign processing. With Abe Peled, a former graduate pupil, he authored the 1976 textbook Digital Signal Processing: Theory, Design, and Implementation, which is a normal reference for engineers. Revealed earlier than digital sign processing had totally emerged as a definite self-discipline, it helped outline the topic for practitioners and college students around the globe.
Liu additionally revealed 250 technical papers and was granted 12 U.S. patents. His papers can be found to learn on the IEEE Xplore Digital Library.
The primary patent granted to him and Peled was in 1976 for a {hardware} design that processed bits in parallel, somewhat than in sequence. The innovation significantly elevated computing effectivity for information together with sound and communication alerts.
Peled says Liu “demonstrated an openness to new concepts and a willingness to problem the orthodoxy of the EE division at the moment—which leaned closely towards extra theoretical info principle.”
A mentor to well-known engineers
Liu’s affect prolonged past his personal analysis. He suggested 53 doctoral college students, a lot of whom went on to distinguished careers in academia and business, together with management positions at Google and IBM. One former pupil, laptop scientist Robert Kahn, helped create the structure of the fashionable Web. Kahn, an IEEE Life Fellow, acquired the 2024 IEEE Medal of Honor.
“His former college students have been very profitable,” Poor mentioned of Liu, “and I feel that’s a testomony to his talent as a mentor.”
“Liu was a extremely impactful scholar and instructor—at all times pondering forward of future wants and altering applied sciences.”—Peter J. Ramadge
Along with a number of Ph.D. college students, Liu developed strategies of filtering and compressing digital alerts to mitigate errors and dramatically cut back the computation wanted for sign processing.
As digital sign processing moved from laboratories into business merchandise, the influence of Liu’s concepts unfold throughout industries. His analysis helped spawn the event of lower-cost and lower-power electronics and contributed to advances in cell communications, multimedia expertise, industrial automation, and biomedical imaging.
A deal with media integrity and copyrights
Within the 2000s, Liu turned his consideration to media integrity and copyright points.
“With the rising accessibility of digital media supply materials, the safety of possession and the prevention of unauthorized alteration has turn out to be an necessary concern,” he wrote in his 2002 ebook, Multimedia Data Hiding. The ebook, which he co-wrote together with his former doctoral pupil IEEE Fellow Min Wu, mentioned the speculation, methods, functions, and safety of digital watermarking—hidden alerts that might establish a real copy of a tune, picture or video to stop unauthorized distribution or tampering.
A Princeton workforce that included Liu, Wu, and one other of his doctoral college students uncovered critical vulnerabilities in watermarking applied sciences being thought-about by an business consortium. They discovered that the standardization efforts have been immature and wouldn’t shield towards digital piracy.
“Now practically each copy of a Hollywood movie given to a critic or theater carries a singular digital forensic watermark to stop unauthorized redistribution,” mentioned Wu.
A power locally
Liu, an energetic IEEE volunteer, served on the IEEE Board of Directors in 1984 and 1985. He was the 1982 president of the IEEE Circuits and Systems Society.
He was a member of the U.S. National Academy of Engineering, an academician of China’s Academia Sinica, and a overseas member of the Chinese Academy of Sciences.
Outdoors the classroom, he was acknowledged for his humility, humor, enthusiasm, and generosity. When pondering of Liu, IEEE Life Fellow Kenneth Steiglitz says, cheer is the primary phrase that involves thoughts.
Liu was “at all times prepared with a optimistic comment, a fast smile or, possibly, some recommendations on the fitting option to cook dinner a duck,” says Steiglitz, professor emeritus of laptop science at Princeton.
Liu inspired his college students to tackle formidable, unconventional tasks, and he impressed college students and colleagues together with his adventurous spirit.
From Your Web site Articles
Associated Articles Across the Net
