Image processor and image processing method generating first and second multi-value density data or performing quantization based on an image characteristic

摘要

Provided is an image processor and image processing method that are capable of suppressing both density unevenness and graininess that occur due to deviation of the printing position of dots that are printed by a plurality of relative movements (or a plurality of printing element groups). In order to accomplish this, the dot overlap rate of an image characteristic in which density unevenness stands out is made higher than the dot overlap rate of an image characteristic in which other defects stand out more than the density unevenness. By doing so, it is possible to suitably adjust the dot overlap rate according to an image characteristic, and to output an image having no density unevenness or graininess.

主权项

1. An image processor for processing input image data of an image to be printed on a unit area which corresponds to a plurality of dots on a printing medium in order to print in the unit area by a plurality of relative movements, including a first relative movement and a second relative movement which is different to the first relative movement, between a printing unit that prints the dots and the printing medium, comprising:
an obtaining unit configured to obtain information about an image characteristic of the image from the input image data; a generation unit configured to perform a generation process for generating from the input image data at least first multi-value density data that corresponds to the first relative movement excluding the second relative movement, and second multi-value density data that corresponds to the second relative movement excluding the first relative movement; and a quantization unit configured to perform a quantization process on each of the first multi-value density data and the second multi-value density data to generate each of a first quantized data which is used for printing in the first relative movement and a second quantized data which is used for printing in the second relative movement, wherein the generation unit performs the generation process or the quantization unit performs the quantization process, based on the information about the image characteristic of the image obtained by the obtaining unit so that a ratio in a case that the obtaining unit obtains an information about a first image characteristic is lower than the ratio in a case that the obtaining unit obtains an information about a second image characteristic which is different to the first image characteristic, the ratio being a ratio of the number of dots that are printed in a same position in the unit area by both of the first and second relative movements on the basis of the first and second quantized data to the total number of dots that are printed in the unit area by the first and second relative movements on the basis of the first and second quantized data.