Patent ID: 6674896
Filing Date: 2004-01-06
Classification: G01N,G06T,G09G

Abstract:
An apparatus comprising:a plurality of color channels, each color channel corresponding to a different component color value, and comprising a subtractor to subtract a component color value of a background color from a component value of a pixel color to produce an adjusted color value; a divider to divide at least one of said component color values by another of said component color values to produce a color ratio; a keyed color indicator to generate a signal in response to each of the adjusted color value and the color ratio falling within an associated range of values corresponding to a keyed color; a first subtractor in a first color channel to subtract a first color component of a background color from a first color component of an input pixel color to produce a first adjusted value; a second subtractor in a second color channel to subtract a second color component of the background color from a second color component of the input pixel color to produce a second adjusted value; a divider to divide the first adjusted value by the second adjusted value to produce a first color ratio; a first comparison circuit to determine if the first color ratio falls in a first range of values; a second comparison circuit to determine if the second adjusted color falls in a second range of values; and a logic circuit to output a signal indicative of a keyed color in response to the first color ratio falling within the first range and the second adjusted color falling within the second range.