Image processing apparatus, printing apparatus, and image processing method

摘要

When an input image is shifted by 640 pixels from a test pattern with reference to the position of a nozzle, the remainder is obtained by dividing 640 pixels by pixels of the dither matrix in an x direction. For example, when the size of the dither matrix in the x direction is 256 pixels, the dither matrix is shifted by 128 pixels in a direction reverse to the x direction. In this manner, the phase of the dither matrix at the time of the quantization during test pattern printing matches the phase of the dither matrix at the time of the quantization during input image printing. Consequently, unevenness of the dither matrix at a position N becomes the same in both of the test pattern and the input image. The HS correction to density unevenness caused by the unevenness of the dither matrix becomes suitable for the input image.

主权项

1. An image processing apparatus that generates print data used for performing printing using one or more printing element arrays in each of which printing elements are arrayed, said apparatus comprising:
a determining unit configured to determine a correction parameter for each of unit areas in an array direction of the printing elements, based on a measurement result of a test pattern printed based on data that has been subjected to quantization using a dither matrix; a correction unit configured to apply the correction parameter to image data by switching the application of the correction parameter per unit area so as to correct the image data; and a quantization unit configured to quantize the image data corrected by said correction unit by using the dither matrix, for generating print data, wherein a phase of the dither matrix with respect to the printing element array in the quantization of the test pattern, to which the dither matrix is applied, matches a phase of the dither matrix with respect to the printing element array in the quantization of the image data, to which the dither matrix is applied.