Method of separation and formation of a color component of a color image and apparatus therefor

Claim 1

A method of producing a synthesized color output from a color image original, comprising the steps of: exposing the color image original to a light source; generating a first color input and a second color input from the light-exposed color image original, wherein said first and second color inputs represent respective exposures of the color image original in two different ranges of light wavelengths; converting said first color input to a first output level signal having a plurality of component level signals representing converted output levels of selected chromatic components and black and white components of said first color input; converting said second color input to a second output level signal having a matching plurality of component level signals as said first output level signal representing converted output levels of the selected chromatic components and black and white components of said second color input; processing said first and second output level signals to produce a synthesized output level signal having a matching plurality of synthesized component level signals by multiplying said first output level signal by a selected first constant "a " and multiplying the inverse of said second output level signal by a selected second constant "b " and adding said multiplied output level signals together, wherein said first constant and said second constant are selected in the predetermined ratio: a:b=k:(1-k), where 0<k<1, such that the output levels of at least some of the selected synthesized chromatic components are separated in levels higher or lower than the output levels of the synthesized black and white components; and producing a synthesized color output based upon the synthesized chromatic components of said synthesized output level signal in accordance with their respective levels of separation from the synthesized black and white components.

Claim 2

A method of producing a synthesized color output from a color image original, comprising the steps of: exposing the color image original to a light source; generating a first color input and a second color input from the light-exposed color image original, wherein said first and second color inputs represent respective exposures of the color image original in two different ranges of light wavelengths; converting said first color input to a first output level signal having a plurality of component level signals representing converted output levels of selected chromatic components and black and white components of said first color input; converting said second color input to a second output level signal having a matching plurality of component level signals as said first output level signal representing converted output levels of the selected chromatic components and black and white components of said second color input; processing said first and second output level signals to produce a synthesized output level signal having a matching plurality of synthesized component level signals by multiplying said first output level signal by a selected first constant "a " and multiplying the inverse of said second output level signal by a selected second constant "b " and adding said multiplied output level signals together, wherein said first constant and said second constant are selected in the predetermined ratio: a:b=k:(1-k), where 0<k<1, such that the output levels of at least some of the selected synthesized chromatic components are separated in levels higher or lower than the output levels of the synthesized black and white components; and producing a synthesized color output based upon the synthesized chromatic components of said synthesized output level signal in accordance with their respective levels of separation from the synthesized black and white components.