Examples relate to a method to print a print job. The method comprise comparing an operational parameter of the print job with a reference operational parameter and determining to perform a maintenance task during the print job based on at least a result of comparing the operational parameter with the reference operational parameter. If the maintenance task is to be performed, the method further comprises determining a safety area on a printable medium and performing a maintenance task on a printable medium.

A method for compensating for failed printing nozzles in an inkjet printing machine uses a computer to provide an increased ink drop volume of adjacent nozzles. All existing printing nozzles are measured regarding print failure and deviation of a printed dot beyond a specific threshold, so that the printing nozzles are marked either as functioning, failed, or printing a dot deviating in a direction transverse to the printing direction, and the results are saved on the computer. The computer hides all functioning printing nozzles and marks all remaining isolated printing nozzles as failed nozzles. The computer groups adjacent remaining printing nozzles by marking nozzles printing a dot deviating in a direction transverse to the printing direction as functioning printing nozzles contributing to the compensation or as failed printing nozzles in accordance with a rule, and the computer compensates for all printing nozzles having been marked as failed.

A printing apparatus includes a printing head provided with a first nozzle row and a second nozzle row arranged shifted from the first nozzle row in a nozzle alignment direction, and a control unit configured to control ejection of ink from nozzles included in the printing head onto a medium based on print data. The control unit is configured to set an image to be complemented as a partial region of an image to be printed on the medium in accordance with a boundary portion between the first nozzle row and the second nozzle row, assign print data for printing the image to be completed to at least one of a first adjacent nozzle that is a nozzle in the first nozzle row and adjacent to the boundary portion and a second adjacent nozzle that is a nozzle in the second nozzle row and adjacent to the boundary portion, and complement the image to be complemented by ink ejection from at least one of the first adjacent nozzle and the second adjacent nozzle.

There is provided a liquid discharge apparatus including: a head having nozzles; a conveyer; and a controller. The controller is configured to carry out a conveyance process of conveying a recording medium in a conveyance direction, and a discharge process of discharging a liquid from the nozzles to the recording medium. The discharge process includes a plurality of discharge steps carried out to a unit area of the recording medium based on data obtained by decomposing an image data into complementary patterns. In at least one of the discharge steps corresponding to the unit area, a function of a discharge duty of the nozzles has an ascending portion or a descending portion. The controller is configured to carry out before the discharge process: a detection process of detecting a defect nozzle in the nozzles; and in a case that the defect nozzle is detected, a change process of changing the function.

A recording method for performing recording on a medium by forming dots by ejecting a liquid from nozzles during scanning. The recording method includes detecting an abnormal nozzle; disposing a normal nozzle in a row where dot missing occurs due to the abnormal nozzle by moving a medium by a first moving amount; performing first complementary recording in which at least a part of a dot missing region is complemented by a first dot which is recorded by the normal nozzle during the scanning; moving the medium by a second moving amount; and performing second complementary recording in which a second dot of which a size is greater than a size of a dot determined based on printing data is recorded on a row adjacent to a row of the abnormal nozzle by the normal nozzle that is positioned adjacent to the abnormal nozzle during the scanning.

A recording device includes a recording unit, a scanning unit, and a recording control unit. The recording unit includes first and second recording parts each having multiple discharge orifice rows that each have multiple discharge orifices arrayed in a predetermined direction. The first recording part and the second recording part are separated from each other in an intersecting direction that intersects the predetermined direction. The scanning unit performs recording scanning by moving the recording unit. The recording control unit performs recording of a region on the recording medium including one edge of the recording medium by the first recording part alone, recording of another region including the other edge of the recording medium by the second recording part alone, and recording of a region in between the two regions using both recording parts.

A printer includes an ejecting head, and a printing control section, in which the ejecting head ejects ink onto the sheet while performing scanning of a plurality of times with respect to a predetermined raster line which extends in the scanning direction. In addition, the printing control section sets a nozzle use rate of a first complementing nozzle which is higher than a nozzle use rate in normal operation as a nozzle use rate of a complementing nozzle which ejects ink to a pixel to which a defective nozzle should eject ink on the sheet, instead of the defective nozzle, when the defective nozzle is detected, and sets a nozzle use rate of a second complementing nozzle which is lower than that of the first complementing nozzle as a nozzle use rate of a supplementary complementing nozzle which is the peripheral nozzle of the complementing nozzle.

A method of printing an image with a printhead having spatially offset groups of drop ejectors, each group having a plurality of drop ejectors that are aligned substantially along a scan direction, includes enabling simultaneous firing of drop ejectors that are corresponding members of a first set of groups. Drop ejectors within each group of the first set are sequentially fired until each member of each group has had opportunity to fire. Corresponding drop ejectors of a second set of groups are simultaneously fired, and drop ejectors within each group of the second set are sequentially fired. Any additional groups of drop ejectors are likewise fired until all drop ejectors have had opportunity to fire during a first stroke. Drop ejectors are fired in subsequent strokes similar to the first stroke as the recording medium is moved relative to the printhead along the scan direction until printing is completed.

The present disclosure relates particularly but not exclusive to a method for printing in a multipass print mode using a first printhead (PT1) and a second printhead (PT2), the method including printing in a first pass a first image in a first area of a print medium using a first set (ST21) of nozzles (N5-N24) from the first printhead (PT1), printing in a second pass a coating layer over the first image using a second set (ST22) of nozzles (P4-P22) from the second printhead (PT2), and printing in a third pass a second image over the coating layer using a third set (ST23) of nozzles (N1-20) from the first printhead (PT1).

This invention provides an image processing apparatus for generating image data for recording in a recording apparatus including a recording unit including a plurality of nozzles discharging ink, comprising a converting unit which converts, based on characteristic information according to a characteristic of each nozzle included in the recording unit, image data corresponding to an input print job into image data to be used for recording by the recording unit; and a control unit which executes one of a plurality of correction processes based on image data obtained by reading an image recorded by the recording unit, wherein the plurality of correction processes include first correction processing that is performed after the recording of the image according to the print job is stopped, and second correction processing that is performed without stopping the recording of the image according to the print job.