Method of producing color correction signals and color separation signals

Claim 1

A method for producing at least one color signal useful in multi-color printing, comprising the steps of generating trichromatic primary color separation signals, forming difference signals between pairs of the trichromatic primary color separation signals, separating the difference signals according to their polarity such that each of the separated difference signals predominantly represents two of the six basic colors of the color space to thereby produce partial signals, inverting the partial signals to form inverted partial signals with the same amplitude but of opposite polarity from the existing partial signals, selecting a pair of signals from said partial signals and said inverted partial signals which in part represent the same basic color with the same polarity, and comparing the amplitudes of the signals within the selected pair to select the signal having the smaller amplitude of the pair, which signal substantially represents a single basic color useful in multicolor printing.

Claim 2

A method for producing at least one color signal useful in multi-color printing, comprising the steps of generating trichromatic primary color separation signals, forming difference signals between pairs of the trichromatic primary color separation signals, separating the difference signals according to their polarity such that each of the separated difference signals predominantly represents two of the six basic colors of the color space to thereby produce partial signals, inverting the partial signals to form inverted partial signals with the same amplitude but of opposite polarity from the existing partial signals, selecting a pair of signals from said partial signals and said inverted partial signals which in part represent the same basic color with the same polarity, and comparing the amplitudes of the signals within the selected pair to select the signal having the smaller amplitude of the pair, which signal substantially represents a single basic color useful in multicolor printing.

Claim 3

A method for producing at least one color signal useful in multi-color printing, comprising the steps of generating trichromatic primary color separation signals, forming difference signals between pairs of the trichromatic primary color separation signals, separating the difference signals according to their polarity such that each of the separated difference signals predominantly represents two of the six basic colors of the color space to thereby produce partial signals, inverting the amplitudes of the partial signals to form inverted partial signals, selecting a pair of said inverted partial signals which in part represent the same basic color with the same polarity, and comparing the amplitudes of the signals within the selected pair to select the signal having the greater amplitude of the pair, which signal will then substantially represent a single basic color useful in multi-color printing.

Claim 4

A method for producing at least one color signal useful in multi-color printing, comprising the steps of generating trichromatic primary color separation signals, forming difference signals between pairs of the trichromatic primary color separation signals, separating the difference signals according to their polarity such that each of the separated difference signals predominantly represents two of the six basic colors of the color space to thereby produce partial signals, inverting the amplitudes of the partial signals to form inverted partial signals, selecting a pair of said inverted partial signals which in part represent the same basic color with the same polarity, and comparing the amplitudes of the signals within the selected pair to select the signal having the greater amplitude of the pair, which signal will then substantially represent a single basic color useful in multi-color printing.

Claim 6

A method of color correction for multi-color printing usiNg three primary color separation signals comprising the steps of separating each primary color separation signal into positive and negative primary color signals, forming first difference signals by adding to each of said positive primary color signals one of said negative primary color signals, separating said first difference signals into signals of positive and negative polarity, selecting six pairs of said separated first difference signals having signal components representing the same basic color but with different polarities, forming second difference signals of the selected pairs by adding the positive and negative first difference signals, separating said second difference signals into signals of positive and negative polarity, selecting pairs of the separated second difference signals with the same basic color but with different polarity, and adding said separated second signals to said primary color signals for color correction.

Claim 7

A method of color correction for multi-color printing usiNg three primary color separation signals comprising the steps of separating each primary color separation signal into positive and negative primary color signals, forming first difference signals by adding to each of said positive primary color signals one of said negative primary color signals, separating said first difference signals into signals of positive and negative polarity, selecting six pairs of said separated first difference signals having signal components representing the same basic color but with different polarities, forming second difference signals of the selected pairs by adding the positive and negative first difference signals, separating said second difference signals into signals of positive and negative polarity, selecting pairs of the separated second difference signals with the same basic color but with different polarity, and adding said separated second signals to said primary color signals for color correction.

Claim 8

A method of color correction for multi-color printing using three primary color separation signals comprising the steps of separating each primary color separation signal into a positive and negative primary color signal, forming first difference signals by adding to each of said positive primary color signals one of said negative primary color signals of another primary color but with a different polarity to remove one color components and the white value, separating said first difference signals into a positive and a negative first difference signals, selecting a pair of said positive and negative first difference signals which have signal components representing the same basic color with the same polarity, selecting one of the two signals of each said pair with regard to instantaneous amplitude, wherein said selected signals represent individual basic colors, and adding said selected signals to the primary color separation signals for color correction.

Claim 9

A method of color correction for multi-color printing using three primary color separation signals comprising the steps of separating each primary color separation signal into a positive and negative primary color signal, forming first difference signals by adding to each of said positive primary color signals one of said negative primary color signals of another primary color but with a different polarity to remove one color components and the white value, separating said first difference signals into a positive and a negative first difference signals, selecting a pair of said positive and negative first difference signals which have signal components representing the same basic color with the same polarity, selecting one of the two signals of each said pair with regard to instantaneous amplitude, wherein said selected signals represent individual basic colors, and adding said selected signals to the primary color separation signals for color correction.