Portal de Periódicos da CAPES

The hardware of digital image handling

2020; Academic Press; Linguagem: Inglês

10.1016/bs.aiep.2020.04.008

1076-5670

W. O. Saxton,

Image Processing Techniques and Applications

Reviews the hardware available for converting images to/from digital form, and the capabilities of computers, at the time of writing. (i) Laser-optical benches versus digital computing. (ii) Input/output of images: microdensitometry of photographic emulsions; quasi-TV-camera systems (low quality); sampling apertures, noise levels; filmwriters (high quality); low-quality expedients using text printers, dot matrix printers, storage oscilloscopes, pen-plotters. (iii) Processors, representation, storage—most computers being too small to hold images in main memory (RAM); integer versus floating-point values (rare at the time); secondary memory (two magnetic tapes; a small disc); special arithmetic units; description of a DEC PDP 8/e system at the Cavendish Laboratory, Cambridge—requiring 9 min to transform a 2562 image at a time—when an IBM 370 mainframe (with ample RAM) required about 7 sec.