Printing apparatus, printing method, printing data generation program, and dither mask generation method

摘要

A printing apparatus which forms dots, according to dot data generated through comparison of a grayscale value of each of pixels with each of threshold values of a dither mask. The printing apparatus forms the dots through division into a plurality of pixel groups having different printing conditions and performs at least a part of the dot formation by the pixel groups in a common region. The dither mask has a second threshold value disposition, with respect to a first threshold value disposition which is each of dispositions of the respective threshold values set such that distribution of dots formed in the common region has noise characteristics having a peak on a high frequency side, in a case where a relative position of the dots between the pixel groups is formed in a target positional relationship which is a target in at least a part of a printing grayscale region.

主权项

1. A printing apparatus which forms dots on a printing medium and prints an image, comprising:
a printing portion that forms the dots on the printing medium and prints the image according to dot data, indicating whether or not the dots are formed, generated through comparison of a grayscale value of each of pixels based on image data of the image to be printed with each of threshold values of a dither mask which is prepared in advance, wherein the printing portion forms the dots through division into a plurality of pixel groups having different printing conditions and performs at least a part of the dot formation by the plurality of pixel groups in a common region, wherein the dither mask has a second threshold value disposition where threshold values corresponding to a part of groups of the plurality of pixel groups are shifted by a predetermined pixel in a predetermined direction, with respect to a first threshold value disposition which is each of dispositions of the respective threshold values set such that distribution of dots formed in the common region has noise characteristics having a peak on a high frequency side in the spatial frequency region, in a case where a relative position of the dots between the pixel groups is formed in a target positional relationship which is a target in at least a part of a printing grayscale region, wherein the predetermined direction is one or two directions, wherein the printing apparatus has singularity in a direction where a relative position of dots between the pixel groups is shifted from a target positional relationship which is a target, and wherein, in relation to a shift amount of the threshold value in the second threshold value disposition, a shift amount in a direction different from a specific direction having the easily shifted singularity is larger than a shift amount in the specific direction.