Abstract: A slicer in a material drop ejecting three-dimensional (3D) object printer determines the number of material drops to eject to form a perimeter in an object layer and distributes a quantization error over the layers forming the perimeter. The slicer also identifies the location for the first material drop ejected to form the perimeter using a blue noise generator.

Abstract: A slicer in a material drop ejecting three-dimensional (3D) object printer identifies the positions and local densities for a plurality of infill lines within a perimeter to be formed within a layer of an object to be formed by the printer. The local density of each infill line is filtered and a control law is applied to the filtered local density to identify an error in the local density compared to a target density. This process is performed iteratively until the error is within a predetermined tolerance range about the target local density. The error is used to generate machine ready instructions to operate the 3D object printer to achieve the target density for the infill lines.

Abstract: Examples of the preferred embodiments use an ink quantity metric (e.g., lightness L*, darkness, image density, line width) of printed content to determine thickness of fountain solution applied by a fountain solution applicator on an imaging member surface and/or determine image forming device real-time image forming modifications for subsequent printings. For example, in real-time during the printing of a print job, a sensor (e.g., spectrometer) may measure the ink quantity metric of the current printing on print substrate. Based on this measurement of printed content output from the image forming device, the image forming device may adjust image forming (e.g., fountain solution deposition flow rate) to reach or maintain a preferred fountain solution thickness on the imaging member surface for subsequent (e.g., next) printings of the print job.

Abstract: A method is disclosed. For example, the method executed by a processor of a multi-function device (MFD) includes tracking a machine state of the MFD, predicting a potential defect based on a determination that the machine state is associated with a defect class of a plurality of different defect classes, determining a maintenance routine associated with the defect class, and executing the maintenance routine to prevent the potential defect.

Abstract: A system and method are provided for registering source and target images. The method includes receiving a first source image and a first scanned image. The first scanned image is one that has been generated by scanning a printed page that has been generated by printing the first source image or a transformed first source image derived from the first source image. Locations of corners of a target image in the first scanned image are identified. With a first computed transform, the corners of the target image in the first scanned image are aligned to corners of the first source image to generate an aligned target image. Local features in the source image and aligned target image are detected. A second transform is computed to align the target image with the first source image, based on the detected local features.

Abstract: According to aspects of the embodiments, there is provided a method of measuring the amount of fountain solution using a hot wire anemometer. Fountain solution thickness is measured using the flow rate of vaporized fountain solution and comparing to baseline air only flow rate. The vaporized measurement is correlated with the baseline utilizing specific heat, density and enthalpy values and keeping velocity of fluid constant. Changes in the measurement will then be related to the specific heat, density and enthalpy. Density can be back calculated to yield volume and knowing the area of the image being printed give a real time thickness value.

Abstract: A system and method are provided for registering source and target images. The method includes receiving a first source image and a first scanned image. The first scanned image is one that has been generated by scanning a printed page that has been generated by printing the first source image or a transformed first source image derived from the first source image. Locations of corners of a target image in the first scanned image are identified. With a first computed transform, the corners of the target image in the first scanned image are aligned to corners of the first source image to generate an aligned target image. Local features in the source image and aligned target image are detected. A second transform is computed to align the target image with the first source image, based on the detected local features.

Abstract: Examples of the preferred embodiments use an ink quantity metric (e.g., lightness L*, darkness, image density, line width) of printed content to determine thickness of fountain solution applied by a fountain solution applicator on an imaging member surface and/or determine image forming device real-time image forming modifications for subsequent printings. For example, in real-time during the printing of a print job, a sensor (e.g., spectrometer) may measure the ink quantity metric of the current printing on print substrate. Based on this measurement of printed content output from the image forming device, the image forming device may adjust image forming (e.g., fountain solution deposition flow rate) to reach or maintain a preferred fountain solution thickness on the imaging member surface for subsequent (e.g., next) printings of the print job.

Abstract: A method of printer operation identifies inkjets to operate in each scanline to eject sneeze drops or, in an alternative approach, identifies the cross-process direction scanlines within a page to be printed by the printer where each inkjet ejects sneeze drops. The methods use a binary grayscale code counter that generates a sequence of binary grayscale code numbers and every other output of the sequence is bit reversed to spread the sneeze drops over the pages of the printer output so the sneeze drops are not perceptible to a human observer.

Abstract: An extruder head has an arrangement of multiple nozzles in the faceplate that avoids aligning the multiple nozzles at angular orientations from the 0°-180° axis and 90°-270° axis intersection at the center of the faceplate. The extruder head includes a housing having a faceplate with a plurality of nozzles that are equally spaced from one another when the nozzles are projected onto a first axis in a plane of the faceplate and the nozzles are equally spaced from one another when projected onto a second axis in the plane of the faceplate that is orthogonal to the first axis. Movement of the extruder head along any angular path from the intersection of the first axis and the second axis in the plane of the faceplate enables at least one nozzle in the plurality of nozzles to not be aligned with any other nozzle.

Abstract: Methods, apparatuses, devices, and systems are disclosed herein for upscaling an input image to a higher resolution while simultaneously converting the image data from a multi-drop state to a binary state. These systems and methods use a probabilistic combination of randomized and biased positioning of inkjet firings in order to yield perceptibly lower graininess in low-coverage areas of output prints without introducing new artefacts.

Abstract: Methods, apparatuses, devices, and systems are disclosed herein for upscaling an input image to a higher resolution while simultaneously converting the image data from a multi-drop state to a binary state. These systems and methods use a probabilistic combination of randomized and biased positioning of inkjet firings in order to yield perceptibly lower graininess in low-coverage areas of output prints without introducing new artefacts.

Abstract: A printer includes a plurality of printheads, a plurality of printhead drivers, and an optical sensor configured to generate image data of a substrate after the substrate has been printed by the plurality of printheads. A controller operates the printheads using the printhead drivers to print a pattern of ink drops on the substrate, determine from image data of the ink drop pattern received from the optical sensor whether a density response for the pattern of ink drops for each printhead is within a predetermined range about a reference density response for the pattern of ink drops, identify a peak voltage for each printhead determined to have the density response outside the predetermined range, and store the identified peak voltage in the printhead driver for the printhead. The printhead driver uses the identified peak voltage to generate firing signals for the printhead operatively connected to the printhead driver.

Abstract: A method of operating an inkjet printer that forms textual data with non-absorbing media ink on non-absorbing media forms the characters with structure that improves the integrity of the edges of the characters over previously known systems. The method includes modifying character pixels in image data used to generate firing signals for operating inkjets in a print head of an inkjet imaging device, generating firing signals for operating the inkjets from the modified character pixels, and operating the inkjets in the print head with the generated firing signals to eject drops of non-absorbing media ink onto non-absorbing media to form characters on the non-absorbing media. The character pixel modification reduces a number of character pixels in a connecting zone of a character that have a value that corresponds to a firing signal that activates an inkjet.

Abstract: A color management system acquires first color data for a color patch of a test pattern printed by a first image forming device on a recto side of a sheet, acquires second color data for the color patch in the test pattern printed by the first image forming device; and acquires third color data for a corresponding color patch in the test pattern printed by a second image forming device on a recto side of a sheet which has passed through the first image forming device. The system applies a correction to the third color data, which is a function of a difference between the first color data and the second color data and which may also be a function of a difference between the second color data and the third color data.

Abstract: A method for operating a three-dimensional object printer compensates for inoperative ejectors. The method identifies image data values associated with an inoperative ejector that stored in a memory with other image data values for a three-dimensional object to be printed by the three-dimensional object printer. The method replaces the image data values associated with the inoperative ejector with image data values associated with an operative ejector that correspond to a material that is different than a material ejected by the inoperative ejector and operates a plurality of ejectors with reference to the other image data values and the replaced image data values to enable the operative ejector to eject drops of the material that is different than the material ejected by the inoperative ejector into the three-dimensional object at positions where the inoperative ejector would have ejected material.

Abstract: An extruder head has an arrangement of multiple nozzles in the faceplate that avoids aligning the multiple nozzles at angular orientations from the 0°-180° axis and 90°-270° axis intersection at the center of the faceplate. The extruder head includes a housing having a faceplate with a plurality of nozzles that are equally spaced from one another when the nozzles are projected onto a first axis in a plane of the faceplate and the nozzles are equally spaced from one another when projected onto a second axis in the plane of the faceplate that is orthogonal to the first axis. Movement of the extruder head along any angular path from the intersection of the first axis and the second axis in the plane of the faceplate enables at least one nozzle in the plurality of nozzles to not be aligned with any other nozzle.

Abstract: A method for operating a three-dimensional object printer compensates for inoperative ejectors. The method identifies image data values associated with an inoperative ejector that stored in a memory with other image data values for a three-dimensional object to be printed by the three-dimensional object printer. The method replaces the image data values associated with the inoperative ejector with image data values associated with an operative ejector that correspond to a material that is different than a material ejected by the inoperative ejector and operates a plurality of ejectors with reference to the other image data values and the replaced image data values to enable the operative ejector to eject drops of the material that is different than the material ejected by the inoperative ejector into the three-dimensional object at positions where the inoperative ejector would have ejected material.

Abstract: A three-dimensional object printer has a controller that operates pluralities of ejectors ejecting drops of different materials having different colors, at least one color of which is white, to produce objects with different levels of color saturation. The controller operates the pluralities of ejectors with reference to a function of a sum of an average number of drops per voxel in each layer, a target value of an average number of drops per voxel of colorants other than white in each layer, and a distance from a closest surface of the object for each material ejected by the ejectors. At a predetermined distance from a closest surface and greater, the controller operates the pluralities of ejectors to form voxels in layers of the object with only clear and white drops. At distances less than the predetermined distance, the number of clear drops increases and the number of white drops decreases.

Abstract: A method of balancing responses of a plurality of sensor chips arranged generally in a linear array comprising: exposing the plurality of sensor chips to an absence of illumination; measuring a dark response of each photosensor of a plurality of photosensors; positioning a calibration piece within a field of view of the plurality of sensor chips other than a calibration sensor chip; illuminating a calibration standard and the calibration piece with a light source; measuring a light response of each photosensor of the plurality of photosensors; applying an offset to the light response of each photosensor of the plurality of photosensors by subtracting the dark response of each photosensor of the plurality of photosensors to obtain an offset light response for each photosensor of the plurality of photosensors; calculating a mean offset light response for each sensor chip of the plurality of sensor chips by averaging the offset light response for each photosensor of the plurality of photosensors in each sensor c