Irwin Sobel

Irwin Sobel is a scientist and researcher in digital image processing, born on 12 September 1940 in New York City. He graduated from the Massachusetts Institute of Technology in 1961 and completed his doctoral research at the Stanford Artificial Intelligence Project, known as SAIL, with a thesis titled Camera Models and Machine Perception; his doctoral advisor was Jerome A. Feldman. From 1973 he spent nine years in postdoctoral research at Columbia University, and after 1982 he worked as a senior researcher at HP Labs. He is remembered for the image gradient method that carries his name. In 1968 he gave a talk at SAIL entitled An Isotropic 3x3 Image Gradient Operator, and the technique became known as the Sobel operator. It was developed jointly with a colleague at SAIL, Gary Feldman.