JP2012228855A5 - Image processing apparatus, image processing method, and image recording apparatus - Google Patents

Description

  The present invention relates to an image processing apparatus, an image processing method, and an image recording apparatus, and more particularly to image processing for generating recording data using a mask for so-called multi-pass recording.

  The present invention solves the above-described problems and can reduce density unevenness that can occur in a band where printing is completed by a plurality of scans when a mask with a non-uniform printing ratio is used, An object is to provide an image processing method and an image recording apparatus.

  Therefore, in the present invention, a recording head having a nozzle row in which a plurality of nozzles for ejecting ink are arranged in a predetermined direction is scanned with respect to the recording medium, and the scanning is performed a plurality of times with respect to the unit area of the recording medium According to each of a plurality of print data corresponding to each of a plurality of scans, the plurality of nozzles in the nozzle row are divided into groups, and ink is ejected to the unit region from each of the plurality of nozzle groups. An image processing apparatus that generates the plurality of recording data based on image data indicating an image to be recorded in order to record an image in a unit area, and that corresponds to an input value of the image data and an ink color. A conversion method for converting the image data into multi-value data corresponding to the ink color by using a conversion table that defines a correspondence relationship between the output values of the value data. And generating means for generating binary data based on each of the multivalued data converted by the converting means, and a print permitting pixel and print permitting corresponding to each of the plurality of scans Generating the plurality of print data by distributing the binary data generated by the generation means to the prints of the plurality of scans based on a plurality of mask patterns in which non-printing permissible pixels are arranged. Distributing means, and the conversion means converts the image data used for recording by a predetermined number of first nozzles arranged at positions corresponding to each other in each of the plurality of nozzle groups to the first Conversion to the multi-value data using the conversion table, and arrangement at positions corresponding to each other in each of the plurality of nozzle groups And image data used for recording by the predetermined number of second nozzles arranged at different positions in the predetermined direction from the predetermined number of first nozzles is different from the first conversion table. When the image data corresponding to the first nozzle and the image data corresponding to the second nozzle show the same color signal when converted into the multi-value data using a conversion table, the distribution Ink is ejected from the first nozzle based on a plurality of print data generated by distributing the first binary data to each of the plurality of scans by means, and is recorded in the unit area. And the second binary data is distributed to each of the plurality of scans by the distributing means, and the second nozzle is controlled by the second nozzle. Correspondences in the first and second conversion tables are defined so that a difference in density between the ink and the image recorded in the unit area is suppressed.

  According to the above configuration, it is possible to reduce density unevenness that may occur in a band in which printing is completed by a plurality of scans when a mask with a non-uniform printing ratio is used.

Claims (12)

A recording head having a nozzle array in which a plurality of nozzles for ejecting ink are arranged in a predetermined direction is scanned with respect to the recording medium, and each of the plurality of scannings is performed in a plurality of scannings with respect to a unit area of the recording medium. According to each of a plurality of corresponding recording data, an image is recorded on the unit area by ejecting ink to the unit area from each of a plurality of nozzle groups in which a plurality of nozzles in the nozzle row are divided into groups. An image processing apparatus that generates the plurality of recording data based on image data indicating an image to be recorded,
Conversion means for converting the image data into multi-value data corresponding to the ink color using a conversion table that defines a correspondence relationship between the input value of the image data and the output value of the multi-value data corresponding to the ink color; ,
Generating means for generating binary data based on each of the multivalued data converted by the converting means;
The binary value generated by the generating unit based on a plurality of mask patterns each corresponding to each of the plurality of scans, each having a print permission pixel that allows printing and a non-print permission pixel that does not allow printing. Distributing means for generating the plurality of print data by distributing data to the prints by each of the plurality of scans, and
The conversion means uses the first conversion table to convert the multi-valued image data used for recording by a predetermined number of first nozzles arranged at positions corresponding to each other in each of the plurality of nozzle groups. The predetermined number of second nozzles that are converted into data and are arranged at positions corresponding to each other in each of the plurality of nozzle groups, and are arranged at positions different from the predetermined number of first nozzles in the predetermined direction. Converting the image data used for recording by the multi-value data using the second conversion table different from the first conversion table,
When the image data corresponding to the first nozzle and the image data corresponding to the second nozzle indicate the same color signal, the first binary data is converted into the plurality of times by the distributing unit. An image in which ink is ejected from the first nozzle and recorded in the unit area based on a plurality of print data generated by being distributed to each of the scans, and the second 2 by the distributing means. Based on a plurality of print data generated by distributing the value data to each of the plurality of scans, the density of the image recorded on the unit area by ejecting ink from the second nozzle An image processing apparatus characterized in that a correspondence relationship in the first and second conversion tables is determined so that a difference is suppressed.   In the plurality of mask patterns, a recording ratio in a mask pattern corresponding to a first nozzle group of the plurality of nozzle groups is different from the first nozzle group of the plurality of nozzle groups in the predetermined direction. The image processing apparatus according to claim 1, wherein the image processing apparatus is set to be smaller than a recording ratio in a mask pattern corresponding to a second nozzle group configured at a position.   The image processing apparatus according to claim 2, wherein the first nozzle group is configured closer to an end side in the predetermined direction than the second nozzle group in the plurality of nozzle groups.   The plurality of mask patterns have a recording ratio in a region corresponding to a nozzle arranged at a first position in the predetermined direction among a plurality of nozzles in the nozzle row, among a plurality of nozzles in the nozzle row. In the predetermined direction, the recording ratio is set to be lower than the recording ratio in the region corresponding to the nozzle arranged at the second position farther from the end in the predetermined direction of the nozzle row than the first position. The image processing apparatus according to claim 1, wherein the image processing apparatus is an image processing apparatus.   The plurality of mask patterns are arranged at the first position in the predetermined direction from a region corresponding to the nozzle arranged at the second position in the predetermined direction among the plurality of nozzles in the nozzle row. The image processing apparatus according to claim 4, wherein the recording ratio is determined to gradually decrease as the position changes to the area corresponding to the nozzle.   The predetermined mask pattern of the plurality of mask patterns is determined such that a recording ratio in an area corresponding to the first nozzle and a recording ratio in an area corresponding to the second nozzle are different from each other. The image processing apparatus according to claim 1, wherein the image processing apparatus is an image processing apparatus.   Each of the plurality of mask patterns is determined such that a recording ratio in an area corresponding to the first nozzle and a recording ratio in an area corresponding to the second nozzle are different from each other. The image processing apparatus according to claim 6. Using a colorimetric conversion table corresponding commonly to the first nozzle and the second nozzle in the nozzle row, predetermined image data indicating the same color signal is output to the first nozzle corresponding to the first nozzle. Second conversion means for converting each of the colorimetric multivalue data and the second colorimetric multivalue data corresponding to the second nozzle;
The first and second colorimetric binary data corresponding to the ink color are generated based on the first and second colorimetric multivalued data converted by the second conversion unit. Two generating means;
By distributing the first and second colorimetric binary data generated by the second generation unit to each of the plurality of scans based on the plurality of mask patterns, a plurality of colorimetry is performed. Second distribution means for generating recording data for use;
Recording control means for controlling to record a colorimetric image on the recording medium by ejecting ink according to the plurality of colorimetric recording data generated by the second distribution means;
Acquiring means for acquiring the first and second conversion tables based on the colorimetric image recorded by the recording control means;
The image processing apparatus according to claim 1, wherein the conversion unit performs conversion using the conversion table acquired by the acquisition unit.   Of the colorimetric image recorded by the recording control unit, an area where ink is ejected from the first nozzle and an area where ink is ejected from the second nozzle are recorded. The image processing apparatus according to claim 8, wherein the densities are different from each other.   Each of the plurality of nozzle groups includes N nozzles, and each of the plurality of nozzle groups includes M (M is 1 ≦ M ≦ N / M) disposed at one end of each of the plurality of nozzle groups. 2 is a natural number satisfying 2), and the second nozzle is composed of M nozzles arranged at the other end of each of the plurality of nozzle groups. The image processing apparatus according to claim 1. A recording head having a nozzle array in which a plurality of nozzles for ejecting ink are arranged in a predetermined direction is scanned with respect to the recording medium, and each of the plurality of scannings is performed in a plurality of scannings with respect to a unit area of the recording medium. According to each of a plurality of corresponding recording data, an image is recorded on the unit area by ejecting ink to the unit area from each of a plurality of nozzle groups in which a plurality of nozzles in the nozzle row are divided into groups. An image processing method for generating the plurality of recording data based on image data indicating an image to be recorded,
Using the conversion table that defines the correspondence between the input value of the image data and the output value of the multi-value data corresponding to the ink color, the image data is converted into multi-value data corresponding to the ink color,
Generating binary data based on each of the converted multi-value data,
Corresponding to each of the plurality of scans, the plurality of binary data generated based on a plurality of mask patterns in which print permitting pixels that allow printing and non-printing allowance pixels that do not allow printing are arranged, respectively. Generating the plurality of print data by distributing the prints to each of the scans;
Converting image data used for recording by a predetermined number of first nozzles arranged at positions corresponding to each other in each of the plurality of nozzle groups into the multi-value data using the first conversion table; In addition, each of the plurality of nozzle groups is used for recording by a predetermined number of second nozzles that are disposed at positions corresponding to each other and that are disposed at positions different from the predetermined number of first nozzles in the predetermined direction. Converting image data into the multi-value data using a second conversion table different from the first conversion table;
In a case where the image data corresponding to the first nozzle and the image data corresponding to the second nozzle indicate the same color signal, the first binary data corresponds to each of the plurality of scans. An image in which ink is ejected from the first nozzle and recorded in the unit area based on a plurality of recording data generated by being distributed to the unit area, and the second binary data is scanned a plurality of times. In order to suppress a difference in density between the image recorded in the unit area by ejecting ink from the second nozzle based on a plurality of recording data generated by being distributed to each of An image processing method characterized in that a correspondence relationship in the first and second conversion tables is defined. An image recording apparatus for recording an image,
A recording head having a nozzle array in which a plurality of nozzles for ejecting ink are arranged in a predetermined direction is scanned with respect to the recording medium, and each of the plurality of scannings is performed in a plurality of scannings with respect to a unit area of the recording medium. An image is recorded in the unit area by ejecting ink to the unit area from each of the plurality of nozzle groups in which the plurality of nozzles in the nozzle row are divided into groups according to the corresponding plurality of recording data. Recording means to
Converts image data indicating an image to be recorded into multi-value data corresponding to the ink color using a conversion table that defines the correspondence between the input value of the image data and the output value of the multi-value data corresponding to the ink color. Conversion means to
Generating means for generating binary data based on each of the multivalued data converted by the converting means;
The binary value generated by the generating unit based on a plurality of mask patterns each corresponding to each of the plurality of scans, each having a print permission pixel that allows printing and a non-print permission pixel that does not allow printing. Distributing means for generating the plurality of print data by distributing data to the prints by each of the plurality of scans, and
The conversion means uses the first conversion table to convert the multi-valued image data used for recording by a predetermined number of first nozzles arranged at positions corresponding to each other in each of the plurality of nozzle groups. The predetermined number of second nozzles that are converted into data and are arranged at positions corresponding to each other in each of the plurality of nozzle groups, and are arranged at positions different from the predetermined number of first nozzles in the predetermined direction. Converting the image data used for recording by the multi-value data using the second conversion table different from the first conversion table,
When the image data corresponding to the first nozzle and the image data corresponding to the second nozzle indicate the same color signal, the first binary data is converted into the plurality of times by the distributing unit. An image in which ink is ejected from the first nozzle and recorded in the unit area based on a plurality of print data generated by being distributed to each of the scans, and the second 2 by the distributing means. Based on a plurality of print data generated by distributing the value data to each of the plurality of scans, the density of the image recorded on the unit area by ejecting ink from the second nozzle An image recording apparatus characterized in that a correspondence relationship in the first and second conversion tables is determined so that a difference is suppressed.