Examples of curl compensation through selective ink depletion are described. In an example, whether printing in a region of a page is likely to produce curling of the page may be determined based on a page location and a print density of the region. The region of the page may be printed with a depleted amount of an ink in response to determining that printing the region at the page location with the print density is likely to produce curling of the page.

A liquid discharge apparatus includes: a head which discharges a plurality of kinds of liquids; and a controller. The controller is configured to: calculate a total discharge amount of the liquids for a unit area of a recording medium based on discharge data for the unit area; determine whether the total discharge amount exceeds a predefined amount; in a case that the controller has determined that the total discharge amount exceeds the predefined amount, divide the discharge data into a plurality of pieces of divided discharge data, each of the pieces of divided discharge data indicating the total discharge amount of not more than the predefined amount; and perform a plurality of divided discharges for the unit area based on the pieces of divided discharge data.

A halftone raster image suitable for rendering a continuous-tone image includes a plurality of spiral dots. The spiral dots include image pixels arranged as a first arc or as a plurality of arcs which together represent a first spiral, and non-image pixels arranged as a second arc or as a plurality of arcs which together represent a second spiral. The spiral dots enable a controlled spreading of the ink within the dot, resulting in a higher image quality, ink saving, and faster drying.

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.

The invention relates to a method for detecting a failing ejection unit in an array of ejection units during printing of a digital image with liquid ink in a printer wherein a medium is transported relative to the array. The printed image is captured to density values on print positions of the printed image. The invented method comprises a step of adapting a halftone mask that is used in preparation of the digital image, such that from a variation in the image density around the line shaped defect the exact nozzle number associated with the failing ejection unit can be determined.

A recording device includes a recording unit configured to execute recording on a recording medium using a color material of cyan, magenta, yellow, and black, and a control unit configured to control recording executed by the recording unit, wherein the control unit causes the recording unit to record an edge region of black data included in image data using at least the color material of black, causes the recording unit to record an inner region on an inner side of the edge region of the black data using at least the color material of cyan, magenta, and yellow, and sets the amount of the color material of black per unit area of the edge region to be greater than the amount of the color material of black per unit area of the inner region.

In an image processing device, a controller performs: acquiring target image data representing a target image; inputting first and second datasets into a machine learning model and causing the machine learning model to output first and second partial dot data; and generating dot data specifying a dot formation state for each of a plurality of pixels in a print image corresponding to the target image using the first and second partial dot data. The first dataset includes first partial image data and a first value for an input parameter. The second dataset includes second partial image data and a second value for the input parameter. The machine learning model outputs the second partial dot data different from the first partial dot data according to the second value being different from the first value even when the second partial image data is identical to the first partial image data.

A printing apparatus includes: a gloss forming unit that forms at least two regions having different gloss levels on a print medium; and a print image forming unit that forms a print image on the at least two regions having different gloss levels of the print medium after the gloss forming unit forms the at least two regions.

An ink printing process employs per-nozzle droplet volume measurement and processing software that plans droplet combinations to reach specific aggregate ink fills per target region, guaranteeing compliance with minimum and maximum ink fills set by specification. In various embodiments, different droplet combinations are produced through different print head/substrate scan offsets, offsets between print heads, the use of different nozzle drive waveforms, and/or other techniques. Optionally, patterns of fill variation can be introduced so as to mitigate observable line effects in a finished display device. The disclosed techniques have many other possible applications.

A printing apparatus includes a head that discharges ink droplets, and a control unit that performs discharge control of the head. When printing a boundary region formed by an end portion of a first image and an end portion of a second image that is lighter than the first image, in discharge control of a specific ink, among a plurality of inks for printing the end portion of the first image, that exhibits lightness, when forming the end portion of the first image, lower than lightness of the end portion of the second image by a predetermined value or more, the control unit performs specific ink discharge control to cause a number of dots per unit area constituting the end portion of the first image to be smaller than a number of dots per unit area constituting a normal portion, of the first image, that is adjacent to the end portion of the first image.