Monochromatic printer and image processing apparatus

An image processing apparatus that converts image data into an expression format based on an on-off state of various types of dots, said image processing apparatus comprising:

• an achromatic color dot creation determination module that determines an on-off state of multiple types of achromatic color dots having different densities, based on the image data;
• a monochromatic hue setting module that sets a monochromatic hue that a monochromatic image has as a whole when carrying out monochromatic printing;
• and
• a chromatic color dot creation module that creates at least one type of chromatic color dots at a predetermined density according to lightness information included in the image data, the chromatic color dot creation module further creating multiple types of achromatic color dots having different densities, wherein the at least one type of chromatic color dots is configured to be mixed with at least one of the multiple types of achromatic color dots so that a printed image has the monochromatic hue set by the monochromatic hue setting module.

An image processing method that converts image data into an expression format based on an on-off state of various types of dots, said image processing method comprising the steps of:

• determining an on-off state of multiple types of achromatic color dots having different densities, based on the image data;
• setting a monochromatic hue that a monochromatic image has as a whole when carrying out monochromatic printing;
• and
• creating at least one type of chromatic color dots at a predetermined density according to lightness information included in the image data and creating multiple types of achromatic color dots having different densities, wherein the at least one type of chromatic color dots is configured to be mixed with at least one of the multiple types of achromatic color dots so that a printed image has the monochromatic hue set by the monochromatic hue setting module.

A computer program embodied on a computer readable medium for converting image data into an expression format based on an on-off state of various types of dots, said computer program comprising:

• program instructions for determining an on-off state of multiple types of achromatic color dots having different densities, based on the image data;
• program instructions for setting a monochromatic hue that a monochromatic image has as a whole when carrying out monochromatic printing;
• and
• program instructions for creating at least one type of chromatic color dots at a predetermined density according to lightness information included in the image data and creating multiple types of achromatic color dots having different densities, wherein the at least one type of chromatic color dots is configured to be mixed with at least one of the multiple types of achromatic color dots so that a printed image has the monochromatic hue set by the monochromatic hue setting module.