Image processing apparatus capable of setting characteristic information for converting target image data

A non-transitory computer readable storage medium storing a set of program instructions for an image processing apparatus comprising a controller, the set of program instructions, when executed by the controller, causing the image processing apparatus to perform:

• acquiring target image data representing a target image to be printed by a printer using a plurality of types of colorant, the target image data including a plurality of pixels, the plurality of types of colorant including a first colorant and a second colorant;
• acquiring a plurality of color component values in a specific color space of each of the plurality of pixels from the target image data, the specific color space being represented by a plurality of color components corresponding to respective ones of the plurality of types of colorant, the plurality of color components including a first color component corresponding to the first colorant and a second color component corresponding to the second colorant, the plurality of color component values including a first color component value for the first color component and a second color component value for the second color component;
• specifying a distribution of color values of the plurality of pixels in the target image data by analyzing the target image data;
• setting a specific range with respect to the plurality of color component values on the basis of the distribution of color values;
• specifying a plurality of index values corresponding to respective ones of the plurality of types of colorant, each of the plurality of index values being related to a quantity of corresponding type of colorant, the plurality of index values including a first index value and a second index value, the first index value being related to a quantity of the first colorant, the second index value being related to a quantity of the second colorant;
• setting characteristic information including first characteristic information and second characteristic information which correlate input values in the specific color space with output values in the specific color space on a one-to-one basis, the input values including a specific input value within the specific range, the specific input value being correlated with a first specific output value by the first characteristic information, the specific input value being correlated with a second specific output value by the second characteristic information, the first specific output value indicating that a colorant consumption quantity for the specific input value is changed from an original colorant consumption quantity for the specific input value by a first colorant quantity, the original colorant consumption quantity being a colorant consumption quantity when assuming that each of the output values is in coincidence with corresponding input value, the second specific output value indicating that the colorant consumption quantity for the specific input value is changed from the original colorant consumption quantity for the specific input value by a second colorant quantity different from the first colorant quantity, at least one of the first characteristic information and the second characteristic information being set on the basis of the specific range in the setting the characteristic information;
• and
• converting the target image data using the characteristic information for generating print data, the print data being supplied to the printer, the converting the target image data including changing the plurality of color component values of each of the plurality of pixels in the target image, the changing the plurality of color component values including:
• changing the first color component value of each of the plurality of pixels as the input value to a first output color component value as the output value according to the first characteristic information;
• and
• changing, when the second index value indicates that the quantity of the second colorant differs from the quantity of the first colorant, the second color component value of each of the plurality of pixels as the input value to a second output color component value as the output value according to the second characteristic information.