An object is to print a high quality image with resistance to print misalignment. To this end, the image processing apparatus generates quantized data for printing a first dot pattern and a second dot pattern in an overlapping manner. The first dot pattern and the second dot pattern are lattice patterns varying in a combination of two basis vectors. In a combined dot pattern obtained by combining the first and second dot patterns, there is a neighboring dot in which a dot in the first dot pattern and a dot in the second dot pattern are arranged at an interval smaller than a lattice spacing. The neighboring dot includes multiple neighboring dots varying in an approach direction.

A first dot pattern printed according to a result of quantization performed on a multi-valued grayscale value by using a first threshold matrix and a second dot pattern printed according to a result of quantization performed on multi-valued grayscale value by using a second threshold matrix are printed on a print medium in an overlapping manner. In order to generate the threshold matrices, a first initial pattern being a dot pattern corresponding to a first grayscale value and a second initial pattern being a dot pattern corresponding to a second grayscale value lower than the first grayscale value are generated for pixel regions of the first and second threshold matrices. Then, thresholds of the first and second threshold matrices are set such that dot patterns having continuity with the first and second initial patterns are obtained at grayscale values between the first and second grayscale values.

A technique capable of suppressing a color shift caused by a variation in ejection characteristics among nozzles is to be provided. A generating unit configured to generate print data which is configured with a printing pixel, which represents that a printing agent is applied, or a non-printing pixel, which represents that a printing agent is not applied, generates the print data as follows: (i) the first quantization data is obtained by quantizing the first image data; and (ii) by applying a correction value based on the ejection characteristics related to a plurality of printing elements for applying a printing agent, a value representing that a printing agent is applied a plurality of times is set for at least one target printing pixel in the first quantization data.

In a printing apparatus configured to print an image by bidirectional multipass printing while using multiple print element rows that apply color material of the same color, a high-quality image suppressed in hue unevenness and density unevenness is printed. To this end, the printing apparatus forms first and second dot patterns on a print medium in an overlapping manner. In the first dot pattern, dot arrays in which first dot groups are arranged at an interval B1 are arranged in a nozzle arrangement direction while being shifted from each other by C1 in a scanning direction of a print head. In the second dot pattern, dot arrays in which the first dot groups are arranged at the interval B1 are arranged in a nozzle arrangement direction while being shifted from each other by C2 in the scanning direction of the print head. Here, values of C1 and C2 are different.

In a printing chip overlapping area being an area in which a first printing chip and a second printing chip overlap with each other when viewed from a second direction, ink is discharged so that a first overlapping area and a second overlapping area at least partially do not overlap with each other when viewed from the second direction. In the first overlapping area, a nozzle usage ratio of a first nozzle row and a nozzle usage ratio of a third nozzle row are neither 0% nor 100%. In the second overlapping area, a nozzle usage ratio of a second nozzle row and a nozzle usage ratio of a fourth nozzle row are neither 0% nor 100%.

A first mask region is a dot recording region including a pixel position on which a dot is recorded, a second mask region is a dot non-recording region including only a pixel position on which a dot is not recorded, recording of dots is performed so as to overlap the first mask regions with each other in a state where the first mask regions of two masks or more among the P masks are shifted from each other on the recording medium, and D1<D3<D2 is satisfied, when a dot charge rate which is a ratio of dots that are recorded in one pass of the entirety of the dots in a first region A1 on an inner side of boundary lines that form an outer edge of the first mask region in the first mask regions is D1.

A printing device includes a printing head with nozzles, a movement mechanism that moves the printing head, and at least one processor. The processor controls the printing head to eject ink from each of the nozzles and to print on each position in a printing target area while causing the movement mechanism to move the printing head; and upon superposing printings in the printing target area based on pieces of data that are different from each other, controls the printing head to eject ink from at least one of the nozzles in each printing onto a different position from a position in a previous printing based on a different piece of data among the pieces of data for each of the superposing printings. The pieces of data is used in specifying from which of the nozzles ink is ejected onto each position in a printable area of the printing device.

A printing apparatus includes a print execution section and a controller. The print execution section includes a printing head which has nozzles for discharging ink of specified color, the nozzles being aligned in a first direction; a head driver which drives the printing head to discharge the ink of the specified color thereby forming dots of the specified color on a printing medium; and a conveyor which conveys the printing medium relative to the printing head in any direction of the first direction and a second direction intersecting with the first direction. The controller is configured to: acquire object image data; generate a plurality of pieces of dot data, which represent formation states of the dots of the specified color, for a plurality of pixels by using the object image data; and print a printing image on the printing medium by using the plurality of pieces of dot data.

An image processing method includes a first conversion step, a second conversion step that, using a second conversion table for converting input image data represented by a second color space to output image data represented by the second color space, converts image data of a second region for which recording conditions are different from a first region in a second image data, and a recording data generating step that generates recording data based on third image data including image data of a first region in the second image data and image data of the second region after conversion using the second conversion table. When adjusting an ink amount, the ink amount is not adjusted in the second conversion step and is adjusted in the first conversion step.

One of printing modes including a first mode in which printing is performed by an even number of scans and a second mode in which printing is performed by an odd number of scans, the odd number being three or more, is executed. In the first mode, printing is performed using a first mask pattern in which the nozzle array is divided into a plurality of blocks each including a first number of continuous nozzles and an ink ejection area or non-ejection area is set for each of the blocks. In the second mode, printing is performed using a second mask pattern in which the nozzle array is divided into a plurality of blocks each including a second number of continuous nozzles, the second number being less than the first number, and an ink ejection area or non-ejection area is set for each of the blocks.