Digital Image Correction and Enhancement is a set of technologies related to producing an altered image in a variety of frequency spectra. The objective of these technologies is to render an image more usable by Fourier or other filtering techniques. These technologies were most actively advanced in the 1960s and early 1970s in the fields of strategic reconnaissance and medical electronics. The term "Digital ICE" initially applied specifically to a proprietary technology developed by Kodak's Austin Development Center (formerly Applied Science Fiction) that automatically removes surface defects, such as dust and scratches, from scanned images. The ICE technology works from within the scanner, so unlike the software-only solutions it does not alter any underlying details of the image. Subsequent to the original "Digital Ice" technology which used infrared cleaning, additional image enhancement technologies were marketed by Applied Science Fiction and Kodak under similar and related names, often as part of a suite of compatible technologies. Digital ICE is used to detect scratches and dust during film scan and not applicable for document scanning. The technology uses a scanner with a pair of light sources, a normal RGB lamp and an IR lamp, and scans twice, once with each lamp. The IR lamp detects the dust locations with its unique detection method and then software corrections are applied based on this data afterwards. The general concept is to subtract the position of scratches and dust from the RGB image.
