Patent ID: 9661181
Date: 2017-05-23
CPC Classifications: B41J,G06K,H04N

Claim:
1. An image processing apparatus for printing an image on a print medium with use of multiple inks, the image processing apparatus comprising one or more processors and one or more computer-readable medias storing a program, the one or more processors and one or more computer-readable media executing the program to function as: a data acquisition unit configured to, for a target pixel, acquire first multi-valued data corresponding to a first ink, second multi-valued data corresponding to a second ink and third multi-valued data corresponding to a third ink; a threshold value acquisition unit configured to acquire a first threshold value corresponding to the target pixel from a threshold value matrix that indicates an array of multiple threshold values; a calculating unit configured to calculate a second threshold value by offsetting the first threshold value with use of the first multi-valued data, and a third threshold value by offsetting the first threshold value with use of the first multi-valued data and the second multi-valued data; and a generating unit configured to generate first quantized data for printing a dot of the first ink by comparing the first multi-valued data and the first threshold value, generate second quantized data for printing a dot of the second ink by comparing the second multi-valued data and the second threshold value, and generate third quantized data for printing a dot of the third ink by comparing the third multi-valued data and the third threshold value, wherein: the threshold value matrix is characterized in that dispersibility of dots printed at positions corresponding to threshold values being continuous from a minimum value to a predetermined value is higher than dispersibility of dots printed at positions corresponding to threshold values being continuous except for from the minimum value to the predetermined value; and the first ink is an ink of a color different from black, and the second ink is a black ink.