Patent ID: 8896883

Claim:
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.