IEEE Spectrum

WikipediaKamisetty Ramamohan “K.R.” Rao died on 15 January 2021 at the age of 89. He co-invented the discrete cosine transform (DCT) technique, which is widely used in digital signal processing and data compression.Rao was a professor of electrical engineering at the University of Texas at Arlington for more than 50 years.This tribute is an excerpted version of an article dedicated to his memory written by three of his colleagues: IEEE Member Jae Jeong Hwang, Zoran M. Milicevic, and IEEE Life Senior Member Zoran S. Bojković. Hwang is a professor of IT convergence and communication engineering at Kunsan National University, in Korea; Miicevic is an assistant professor of telecommunications and IT at the University of Belgrade, in Serbia; and Bojković is a professor of electrical engineering, also at the University of Belgrade.Education and Early CareerRao received a bachelor’s degree in electrical engineering in 1952 from the College of Engineering, Guindy, in Chennai, India. He then moved to the United States and earned two master’s degrees from the University of Florida, in Gainesville: one in EE in 1959 and the other in nuclear engineering in 1960. He received a Ph.D. in 1966 in EE from the University of New Mexico, in Albuquerque.After graduating, he joined UT Arlington as a research professor. He was promoted to associate professor three years later and became a full professor in 1973.In the early 1970s, he began working with Nasir Ahmed, professor emeritus of electrical and computer engineering at the University of New Mexico, to develop DCT. They presented their results in the article “Discrete Cosine Transform,” published in the January 1974 IEEE Transactions on Computers.Similar to the discrete Fourier transform, the DCT converts a signal or image from the spatial domain (a matrix of pixels) to the frequency domain (in which images are represented by mathematical functions).DCT technology reduces the amount of data required to display, store, and transmit images by identifying parts of the image that contain significant amounts of energy—the ones that are most important to retaining image quality.Originally proposed as an image-compression technique, DCT is now an industry standard in image and video coding, commonly used to store and transmit JPEG images as well as MPEG video files. DCT also has applications in digital video and television, speech coding, satellite imaging, signal processing, and telecommunications.Rao went on to develop four different types of the technology: DCT-I, DCT-II (used in image and video compression including high-definition television), DCT-III, and DCT-IV (which has applications in audio coding algorithms).“HDTV would not have been possible without the research accomplished by K.R. Rao and his students and collaborators,” said Venkat Devarajan, a former Rao student who is now an EE professor at UT Arlington.Rao co-authored 22 books, some of which have been translated from English to Chinese, Japanese, Korean, Russian, and Spanish. He also published papers on Walsh functions and a variety of other topics related to image and signal processing.Lasting LegacyDuring his tenure at UT Arlington, he advised more than 100 graduate students. He was a member of the university’s Academy of Distinguished Scholars.He was a visiting professor at universities in Australia, India, Japan, Korea, Singapore, and Thailand. He also conducted workshops and tutorials on video and audio coding and standards around the world.“Everyone speaks about him in the highest regard—not just as a scholar but as a mentor, a friend, a person who helped them, and a person who encouraged them,” said Vistasp Karbhezi, an engineering professor and former president of UT Arlington. “I think that’s his legacy.”

University at BuffaloSargur “Hari” SrihariPioneer of computational forensicsLife Fellow, 72; died 8 MarchSrihari helped create an artificial intelligence system in 1991 that enabled machines to read handwritten letters. The U.S. Postal Service still uses the system to sort mail. Srihari was a pioneer in the field of computational forensics who in 2002 developed CEDAR-FOX, a software system that identifies people through their handwriting.He was a professor of computer science and engineering for more than 40 years. He taught at the State University of New York as well as the University of Buffalo, where he founded its Center of Excellence for Document Analysis and Recognition. The faculty and students use the CEDAR research lab to work on technologies involving pattern recognition, machine learning, data mining, information retrieval, and computational linguistics.It was at CEDAR where Srihari helped develop the AI system. The U.S. Postal Service provided the program with more than US $60 million in funding during the project’s 25 years.In 2002 Srihari created CEDAR-FOX, which has been updated to allow the system to identify people through their fingerprints and shoe prints.Srihari held seven U.S. patents.Because of his expertise, Srihari was asked in 2007 to serve on the U.S. National Academy of Sciences’ committee on identifying the needs of the forensic science community, the only computer scientist on the body. It produced a report in 2009 about how the U.S. criminal justice system could strengthen its use of forensic science.Srihari received bachelor’s degrees in physics and mathematics in 1967 from Bangalore University in India. He also earned a bachelor’s degree in electrical communication engineering in 1970 from the Indian Institute of Science, in Bangalore. Srihari went on to earn a Ph.D. in computer and information science in 1976 from Ohio State University, in Columbus.Charles H. GagerFormer head of Mitre’s space surveillance systemsMember, 91; died 24 MarchGager joined the research and engineering division of AIL, in St. James, N.Y., in 1951. There he conducted research in radar techniques and helped develop technologies such as moving-target identification equipment, monopulse radar, and high-resolution radar.He left the company in 1979 to join The Mitre Corp. in McLean, Va., where he helped develop surveillance sensors and technology for electronic warfare and tactical defense measures. He was promoted in 1984 to head the company’s space surveillance systems department.After he retired, he and his wife moved to Norwell, Mass., and he became an active IEEE volunteer. He also taught a course about the history and evolution of U.S. intelligence operations for Harvard’s Institute for Learning in Retirement.Gager received a bachelor’s degree in electrical engineering in 1950 from the Polytechnic Institute of Brooklyn (now the New York University Tandon School of Engineering).Thomas K. IshiiFounder of the IEEE Microwave Theory and Techniques Society’s Milwaukee SectionLife member, 94; died 27 DecemberIshii was an active IEEE volunteer who established the IEEE Microwave Theory and Techniques Society Milwaukee Section. He served as an associate editor of IEEE Transactions on Circuits and Systems from 1989 to 1991.He served as a consultant for several companies including Wisconsin Electric Power, Honeywell, and Johnson Controls, as well as a number of law firms.Ishii received a bachelor’s degree and a Ph.D. in engineering from Nihon University, in Tokyo. He stayed on as an electrical engineering professor after graduating in 1950. He left six years later to pursue a second master’s degree and a doctorate at the University of Wisconsin-Madison. He graduated in 1959 and joined Marquette University, in Milwaukee, as a professor. He retired in 1998 and was named professor emeritus.He held two U.S. patents and three Japanese patents for microwave devices.Ishii was honored with several awards including the 2000 IEEE Millennium Medal, the 1984 IEEE Centennial Medal, and the 1969 T.C. Burnum IEEE Milwaukee Section Memorial Award.Leland Ross MegargelElectrical engineerLife member, 93; died 13 NovemberMegargel worked as an electrical engineer for several companies including General Electric, Valley Forge, and International Signal and Control.After graduating in 1945 from Lake Ariel Consolidated School, in Pennsylvania, he enlisted in the U.S. Army. He was stationed in Japan and helped with the country’s reconstruction projects following World War II. He was honorably discharged in 1947.He was granted several U.S. patents.Megargel received a bachelor’s degree in electrical engineering in 1951 from Pennsylvania State University.Mirela Sechi Moretti Annoni NotareEditorial advisory board member of The InstituteSenior member, 53; died 14 April 2021Notare was a professor at the Universidade Federal de Santa Catarina, in Florianópolis, Brazil.She was an active IEEE member for 25 years, serving on several boards and committees including The Institute’s editorial advisory board. She was a member of the Region 9 NoticIEEEro newsletter committee and was on the editorial staff of IEEE Latin America Transactions.