1972. The space shuttle program began; the CD, the digital watch, Fortran and C programming languages were invented; and the Atari Company released an explosively popular new product called Pong. In the midst of this, 40 years ago at USC, three remarkable institutions were born. Here are the stories from then and now: the USC Distance Education Network, the Signal and Image Processing Institute, and the Information Sciences Institute, all about big promises made – and delivered.
Signal and Image Processing Institute (SIPI) The cover of the December 1972 issue of USC Engineer contains a blurred image of Earth over the line “image processing.” Almost the entire issue that follows is dedicated to the achievements of a remarkable group of researchers who found each other at USC in the 60’s — led by alumnus William Pratt (EE M.S. ’61 Ph.D. ’65) — and went on to history, a history that included embedding the face of a Playboy model as an icon in the literature. In 1972, a major grant to Pratt led to the founding of the USC Image Processing Institute (IPI), which subsequently transformed the discipline, creating software that remains in daily use today, as the ubiquitous file label JPEG illustrates. IPI was later re-named as the Signal and Image Processing Institute (SIPI) to reflect its expanded research activities. Pratt, now at Pixelsoft, began as a USC graduate student under Irving Reed, a pioneer in the field of information theory. Reed steered him to research in video coding, which became his Ph.D. thesis, one that opened the field to research. At the time, simply capturing an image — either video or a still, electronically — had already been solved. Pratt and his backers created SIPI to solve three related problems: “image coding, 28 Fall 2012
image restoration and enhancement, and image data extraction.” Coding involves reducing the amount of information required to transmit or reproduce video or photos so that, for example, a space satellite could send back volumes of usable images despite severe weight, space and energy limitations. Lots of the initial work was done on a single image: Lena — half a picture from Playboy, scanned by a student, wound up being propagated around the research community and was the prototype subject for a type of coding that is now ubiquitous: the JPEG. The invention of JPEG was not an isolated achievement for SIPI. Other outstanding achievements, many by faculty still at the Viterbi School, include: • MPEG, the moving image equivalent to JPEG in economic recording and transmission of video, with major innovations in fast motion search and rate control contributed by C.-C. Jay Kuo and Antonio Ortega, respectively. • Image recognition and detection, pioneered by Pratt’s close colleague Harry Andrews. • Medical imaging developments, including the “Brainstorm” software system created by Richard Leahy.
PIN UP In 1973, Alexander Sawchuk and the SIPI lab manager needed a glossy color image for a conference paper, and just then, he recalls, somebody happened to walk in with a recent issue of Playboy. “Lena” became the international standard test image for image processing algorithms.
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