A printing system and a printing method are provided. The user terminal includes a print content processing unit and a sliding print content conversion unit, and the handheld printer includes an inkjet printing unit that performs inkjet printing at a predetermined inkjet width in a sliding direction when performing sliding print. The print content processing unit determines the number of sliding print motions and sequentially generates bitmaps corresponding to the respective sliding print motions based on the respective print content mode and the inkjet width, and generates bitmap format instructions corresponding to the respective bitmaps. The sliding print content conversion unit converts pixels in the bitmaps into binary data to form sliding print content. The handheld printer sequentially prints the respective sliding print content based on the respective bitmap format instructions and the print content mode.

Provided are an image processing method, an image processing device, and an image recording apparatus capable of suppressing generation of beats, even in a case where streaky unevenness correction other than non-discharge correction of a recording element is performed, in any nozzle layout shapes. An image processing method comprises an abnormality detection step of detecting an abnormality for each recording element in a recording head in which a plurality of the recording elements are arranged; an invisibilization step of modulating densities of pixels to be recorded on a recording medium by the correction recording element including an abnormal recording element of which the abnormality has been detected to invisibilize a defect of an image, in order to correct the defect of the image resulting from the abnormal recording element depending on a detection result in the abnormality detection step; and a quantization step of quantizing an image to be recorded on the recording medium, and performing the quantization such that a peak frequency component of the quantization is located in a frequency band excluding a frequency band around a spatial frequency peak of a correction region that is a pixel group to be recorded on the recording medium by the correction recording element of which a density has been modulated by the invisibilization step.

An image processing apparatus that converts image data of a first resolution into image data of a second resolution lower than the first resolution. The image processing apparatus determines a small dot that is included in the image data of the first resolution and matches a first small dot pattern and performs conversion from the first resolution to the second resolution by switching a method of generating resolution-converted image data based on a result of the determination.

An object is to save a user's trouble in a case of printing correction charts and stabilization charts and performing automatic tone correction with the correction charts among the printed charts. An image processing apparatus performs: control for printing correction chart images along with identification images for respectively identifying the correction chart images on print media in a one-to-one correspondence; and control for printing a stabilization chart image on a print medium before the control for printing the correction chart images. Then, from among scan images obtained by reading correction charts and one or more stabilization charts, the apparatus identifies the scan images respectively corresponding to the correction charts based on the identification images appearing in the scan images, the correction charts each being obtained by printing a correction chart image along with the corresponding identification image, the stabilization charts each being obtained by printing the stabilization chart image.

Formed is a dither pattern that makes it possible to output an image with excellent dot dispersibility and reduced graininess regardless of controls after quantization processing. To this end, an extended pattern in which multiple divided pixels correspond to each of multiple pixels included in quantization data and one or more of the multiple divided pixels are determined as dot-arrangeable-pixels in which dots can be printed is generated. Thereafter, the thresholds of the dither pattern are set based on the extended pattern in which the dots are arranged to obtain predetermined dispersibility.

An image processing apparatus converts, based on a threshold matrix in which thresholds are arrayed, input image data into a first dot pattern representing dots recorded by a recording head, and obtains a second dot pattern representing dots recorded by each of L number of the nozzle arrays by assigning the dots of the first dot pattern to each of the nozzle arrays so that each nozzle of the recording head is used in a cycle of L. A power spectrum in a frequency domain of the first dot pattern has a blue noise characteristic or a green noise characteristic in which power in a low frequency band is suppressed, and power is suppressed at a frequency corresponding to the cycle of L and at frequencies of multiplications of the frequency.

Provided are an image processing apparatus, an image processing method, a dither mask set, and an image recording apparatus capable of suppressing occurrence of banding and color unevenness without productivity decrease. Halftone processing is performed with respect to image data of a first color, in a range of a part of a recording duty, using a dither mask that realizes a first nozzle jetting rate in which a nozzle jetting rate of an end part nozzle is suppressed to be smaller than a nozzle jetting rate of a central nozzle. Further, halftone processing is performed with respect to image data of a second color different from the first color, using a dither mask that realizes a second nozzle jetting rate having smaller difference between the nozzle jetting rate of the end part nozzle and the nozzle jetting rate of the central nozzle than that in the first nozzle jetting rate.

This image processing apparatus inputs a density value for each pixel of image data and an attribute indicating an object type to which the pixel belongs, processes one pixel of input image data as a pixel of interest in turn, and in accordance with at least the attributes of the pixel of interest and two pixels which sandwich the pixel of interest, executes image processing for replacing the density value of the pixel of interest with the density value of one pixel out of two pixels.

Threshold values in a dither matrix are arranged such that, in a case when screen processing is executed on a multi-tone image that has a first density, halftone dots are formed at a first screen angle, and, in a case when screen processing is executed on a multi-tone image that has a density being higher than a second density that is higher than the first density, halftone dots are formed at a second screen angle that is different from the first screen angle.

Provided are an image processing apparatus, an image processing method, a dither mask set, and an image recording apparatus capable of suppressing occurrence of banding and color unevenness without productivity decrease. Halftone processing is performed with respect to image data of a first color, in a range of a part of a recording duty, using a dither mask that realizes a first nozzle jetting rate in which a nozzle jetting rate of an end part nozzle is suppressed to be smaller than a nozzle jetting rate of a central nozzle. Further, halftone processing is performed with respect to image data of a second color different from the first color, using a dither mask that realizes a second nozzle jetting rate having smaller difference between the nozzle jetting rate of the end part nozzle and the nozzle jetting rate of the central nozzle than that in the first nozzle jetting rate.