Blurred Boundaries [From the Editor]

hat is signal processing and what isn’t? From time to time, I would come across comments related to this question from independent reviews regarding whether an article that was submitted to IEEE Signal Processing Magazine fit the scope. I have seen reviewers recommending an article surveying signal processing techniques for wireless communications to a communications-related publication instead, or an article related to imaging or image analysis to a computer visionrelated venue. This would have been commonly accepted several decades ago when various fields under the IEEE umbrella were well partitioned into different technical Societies. The IEEE Signal Processing Society (SPS) traces its roots to 1948 as the IEEE’s first Society, with the name and scope as the Professional Group on Audio of the then Institute of Radio Engineers (IRE), the predecessor of the IEEE. Looking at the historic roster of the SPS’s technical committees (TCs) (as shown in “SPS Technical Committees Then and Now: Evolved and Broadened Scope of Signal Processing”), we can see that just 40 years ago in 1976 when the Society’s first flagship conference, the International Conference on Acoustics, Speech, and Signal Processing (ICASSP), was launched, there were only five SPS TCs, and they were dealing with either signal processing theories and methods, or speech and acoustics. There was little mention of communications nor much presence of visual processing in the SPS TC structure, even though many fundamental signal processing theories and techniques had been used rather extensively in those areas and further extended and adapted to solve the problems there. Moving forward about ten years, we see that visual aspects in a more general sense of multidimensional signal processing were added to the TC list by the mid-1980s. And now, 40 years later, we see more than a dozen TCs in the SPS, with a diverse range of “new” areas explicitly embraced, including communications and networking, multimedia signal processing, biomedical-related signal processing, and information forensics and security. Year after year, signal processing, together with other fields, have evolved, and the boundaries between several traditionally separate fields have been blurred. Many colleagues have been actively involved in multiple technical societies, fostering interaction and bringing beneficial aspects between fields. Innovations have often happened at the boundaries between traditionally separate fields.