Patent ID: 8576441

Claim:
A profile correcting method comprising: acquiring a device profile indicating correspondence relationships between a plurality of input values and a plurality of sets of first output values, each first output value set corresponding to one of the plurality of input values, each input value representing an achromatic color having a density level, each first output value set including a plurality of chromatic values each representing a chromatic color, the achromatic color being reproduced by mixing the chromatic color; and performing a process for each input value, the process comprising: forming a test patch based on one first output value set corresponding to the each input value; measuring color of the test patch, the color being represented by a set of a*b* values, the a*b* value set including a first a* value and a first b* value which are defined in a CIEL*a*b* color space; determining whether or not the one first output value set is a to-be-corrected first output value set, the to-be-corrected first output value set corresponding to a test patch whose color is represented by an a* b* value set including at least one of the first a* value greater than an a* prescribed value and the first b* value greater than a b* prescribed value, the a* prescribed value and the b* prescribed value being smaller than zero; and correcting, if the one first output value set is the to-be-corrected first output value set, the one first output value set to a second output value set which is to form color that is represented by an a* b* value set including a second a* value and a second b* value, the second a* value being smaller than or equal to the a* prescribed value, the second b* value being smaller than or equal to the b* prescribed value.