Multi-resolution halftoning to process image data by determining whether
the image data corresponds to black image data or color image data,
performing a halftoning process of a first resolution on the black image
data, performing a halftoning process of a second resolution on the color
image data, and performing a smoothing process on the black image data.
The first resolution may be a low resolution and the second resolution may
be a high resolution and the black image data may be expanded into high
resolution data. Image data subjected to multi-resolution halftoning may
be printed by a print head with black nozzles having a faster printing
speed than color nozzles.
