Patent ID: 6249358
Filing Date: 2001-06-19
Classification: H04N

Abstract:
A method of performing gain calibration in a film scanner to correct for pixel-by-pixel variations in scanning system response comprising:a. obtaining a pixel-by-pixel open gate response for the scanning system in which scanning illumination is active but without film present in the scanning system;b. establishing a pixel-by-pixel open gate gain profile in response to said open gate response;c. obtaining a pixel-by-pixel Dmin response for the scanning system in which scanning illumination is active and film is present in the scanning system;d. establishing a pixel-by-pixel Dmin gain profile in response to said Dmin responsee. establishing a pixel-by-pixel composite gain profile from selective combination of said open gate and Dmin gain profiles; andf. on a pixel-by-pixel basis, utilizing the composite gain profile for actual scanning of film images.