Image processing apparatus and method to generate recording data

An image processing apparatus for, to record an image on a recording medium using a plurality of color materials including a first color material and a second color material which has a hue complementary to that of the first color material, processing image data corresponding to the image, the image processing apparatus comprising:

• a conversion unit configured to convert the image data into pieces of color material data corresponding to the plurality of color materials;
• and
• a generation unit configured to, based on the converted pieces of color material data and using a threshold matrix in which a threshold for determining whether a color material is to be recorded or not to be recorded is set for each pixel, generate recording data to be used to record the plurality of color materials,
• wherein the conversion unit converts predetermined image data indicating a color that is an achromatic color and has a gradation less than or equal to an intermediate gradation in a gradation range for color reproduction, into the pieces of color material data such that a recording amount of the first color material and a recording amount of the second color material are larger than a recording amount of a color material different from the first and second color materials among the plurality of color materials,
• wherein based on the color material data corresponding to the first color material and a first threshold matrix in which a threshold for determining whether a color material is to be recorded or not to be recorded is set for each pixel, the generation unit generates recording data corresponding to the first color material,
• wherein based on the color material data corresponding to the second color material and a second threshold matrix in which a threshold for determining whether a color material is to be recorded or not to be recorded is set for each pixel, the generation unit generates recording data corresponding to the second color material, and
• wherein sums of the thresholds set in the first threshold matrix and the thresholds set in the second threshold matrix that correspond to all the pixels are the same value.

An image processing apparatus for, to record an image on a recording medium using a plurality of inks including a yellow ink and a light blue ink, processing image data corresponding to the image, the image processing apparatus comprising:

• an acquisition unit configured to acquire the image data;
• a conversion unit configured to convert the image data into pieces of ink data corresponding to the plurality of inks;
• and
• a generation unit configured to, based on the pieces of ink data, generate recording data to be used to record the plurality of inks,
• wherein the generation unit generates the recording data such that, in a low gradation region of a black hue, a pixel where it is determined according to the recording data that the yellow ink is to be recorded and a pixel where it is determined according to the recording data that the light blue ink is to be recorded are at positions different from each other.

An image processing method for, to record an image on a recording medium using a plurality of color materials including a first color material and a second color material which has a hue complementary to that of the first color material, processing image data corresponding to the image, the image processing method comprising:

• converting the image data into pieces of color material data corresponding to the plurality of color materials;
• and
• based on the converted pieces of color material data, generating recording data to be used to record the plurality of color materials,
• wherein predetermined image data indicating a color that is an achromatic color and has a gradation less than or equal to an intermediate gradation in a gradation range for color reproduction is converted into the pieces of color material data such that a recording amount of the first color material and a recording amount of the second color material are larger than a recording amount of a color material different from the first and second color materials among the plurality of color materials, and
• wherein the recording data is generated such that a pixel where it is determined according to the recording data that the first color material is to be recorded and a pixel where it is determined according to the recording data that the second color material is to be recorded are at positions different from each other.