There are provided a printing system, a method of generating a halftone processing rule, a method of acquiring a characteristic parameter, image processing device and method, a halftone processing rule, a halftone image, a method of manufacturing a printed material, an ink jet printing system, and a program which are capable of reducing an operation load of a user and acquiring a halftone processing rule appropriate for the printing system. A characteristic parameter acquisition chart including a pattern for acquiring characteristic parameters related to characteristics of the printing system is output, and the output characteristic parameter acquisition chart is read by image reading means. The characteristic parameters are acquired by analyzing the read image of the characteristic parameter acquisition chart, and halftone processing rules that define the processing contents of halftone processes used in the printing system are generated based on the acquired characteristic parameters.

A determination unit determines whether a difference between a maximum value and a minimum value of pixel values of a plurality of pixels in a region of interest in N-gradation multi-valued data, where N≥4, representing the pixel values of the plurality of pixels is less than a determination threshold value. A generation unit generates M-gradation quantization data represented by an M-gradation quantization value, where 3≤M<N, based on the N-gradation multi-valued data and the determination. In a case where the determination unit determines that the difference is less than the determination threshold value, the generation unit generates the M-gradation quantization data so that each of the plurality of pixels corresponding to the region has a value that is one of two consecutive values of the M-gradation quantization values in the generated M-gradation quantization data.

A method of printing authentication indicia by applying an at least amplitude-modulated halftone print in a detection zone to an object uses adjoining halftone cells, in each of which a halftone dot is printed from a matrix of printable halftone elements, individual tone values of the halftone print corresponding in each case to a halftone plane of a halftone mountain for a halftone dot. In this process, the assigned screen plane of the screen mountain is modified in the detection zone in a predetermined manner for a plurality of tone values of screen dots to be printed, so that a predetermined matrix image of the screen elements to be printed is assigned to it while the tone value of the print remains constant.

In an example, a machine-readable medium stores instructions which when executed by a processor cause the processor to determine a difference between a measured printed output and an expected printed output. Based on the difference, a first control instruction for controlling a drop size wherein the drop size is variable, and a second control instruction for controlling a dot density of a variable dot density may be determined.

Provided is quantization processing that can reduce color development defect due to dot overlapping and can output an image with reduced granularity when the image is printed by using multiple kinds of colorants. To this end, dot arrangement information for a colorant for which dot arrangement is already determined among multiple kinds of colorants is acquired for a predetermined region of the image, and an evaluation value of each pixel included in the predetermined region is derived based on the arrangement information. In addition, for the predetermined region, a target value for a predetermined colorant for which dot arrangement is yet to be determined is derived based on the image. Then, whether or not to arrange a dot of the predetermined colorant in the predetermined region is determined based on the target value and the evaluation value.

The present disclosure aims to provide a high quality image without conspicuous graininess and density unevenness. An embodiment of the present invention is an apparatus for printing a plurality of dot patterns on a printing medium, the dot patterns being formed by substantially same color and substantially same dot diameter, the apparatus including: a first creation unit configured to create, based on a first tone value, a first dot pattern and a second dot pattern printed and superimposed on the first dot pattern; and a second creation unit configured to create, based on a second tone value larger than the first tone value, a third dot pattern having an equal or larger number of dots compared to the first dot pattern and a fourth dot pattern printed and superimposed on the third dot pattern and having an equal or larger number of dots compared to the second dot pattern.

A quantized value for a pixel of interest in an input image is derived by using a predetermined threshold value matrix. Then, based on a pixel value group in a predetermined reference area including the pixel of interest in the input image and a threshold value group corresponding thereto, directionality of correction is determined. Further, based on the pixel value group and the threshold value group, whether or not the pixel of interest satisfies a predetermined condition for changing the quantized value is determined. Then, based on both the determination results, the quantized value is corrected.

An example operation method of an image forming apparatus includes forming a test image with respect to a pattern used for diagnosing an image-quality state of a printout output by the image forming apparatus, obtaining a test signal corresponding to the test image via a sensor of the image forming apparatus, obtaining image-quality state information indicating an image-quality state of the test image based on the test signal corresponding, identifying a type of a screen corresponding to halftone information indicating a resolution of the printout based on the image-quality state information, and performing a first image forming operation according to the type of the screen.

An image file is prepared for printing. The image file is received. The image file includes a cell having pixels. A pixel of the pixels of the cell corresponds with a command to apply a print substance to a medium. For the pixel, the command to apply the print substance is selectively replaced with a command to not apply the print substance.

Provided is quantization processing that can reduce color development defect due to dot overlapping and can output an image with reduced granularity when the image is printed by using multiple kinds of colorants. To this end, dot arrangement information for a colorant for which dot arrangement is already determined among multiple kinds of colorants is acquired for a predetermined region of the image, and an evaluation value of each pixel included in the predetermined region is derived based on the arrangement information. In addition, for the predetermined region, a target value for a predetermined colorant for which dot arrangement is yet to be determined is derived based on the image. Then, whether or not to arrange a dot of the predetermined colorant in the predetermined region is determined based on the target value and the evaluation value.