Search results
Results From The WOW.Com Content Network
The Luhn algorithm or Luhn formula, also known as the " modulus 10" or "mod 10" algorithm, named after its creator, IBM scientist Hans Peter Luhn, is a simple check digit formula used to validate a variety of identification numbers. It is described in U.S. Patent No. 2,950,048, granted on August 23, 1960. [1]
A gray card is a middle gray reference, typically used together with a reflective light meter, as a way to produce consistent image exposure and/or color in video production, film, and photography . A gray card is a flat object of a neutral-gray color that derives from a flat reflectance spectrum.