Abstract: An example of apparatus to align media. The apparatus includes a printer assembly to form markings a first side of a media. The apparatus also includes a sensor to detect a backside pattern on each pass at multiple locations. The apparatus includes a processor in communication with the sensor. The processor is to compare the backside pattern measured on multiple passes to determine offset amounts. The apparatus also includes a controller to adjust the media relative to the printer assembly based on the offset values.

Abstract: An example of a print media can include a substrate, a removable layer coupled to a surface of the substrate, and an object on a surface of the removable layer, the object including tracking markings to permit determination of a velocity of the print media.

Abstract: An example system for a thermal printing device may comprise a printhead comprising a heat source, where the printhead is to transmit heat from the heat source onto a thermally activated print medium to form markings on a plurality of regions of the thermally activated print medium to form a pixel, and a controller to determine a plurality of voltage pulse patterns prior to formation of the markings on the plurality of regions, determine which of the plurality of regions the plurality of voltage pulse patterns are to activate prior to formation of the markings on the plurality of regions, where the plurality of regions comprise regions with overlapping color layers onto which markings are to be formed with an individual pulse pattern of the plurality of voltage pulse patterns, and send a voltage pulse pattern information to the printhead.

Abstract: Example implementations applying thermal energy to sub-lines. In some examples, a printing device can include a processing resource and a memory resource storing non-transitory machine-readable instructions to cause the processing resource to receive print data about a line to be formed on a thermally activated print medium, divide the line into a plurality of sub-lines, determine a threshold colorant density level of a first sub-line and a third sub-line of the plurality of sub-lines based on the received print data, and cause a print head of the printing device to apply thermal energy to the first sub-line and the third sub-line on the thermally activated print medium using the received print data.

Abstract: In some examples, a system may include a thermal print head including a plurality of print head elements to heat a print medium. The system may include a controller to determine a tri-color tuple of a pixel of an image to be printed; determine an input temperature at a specific print head element, of the plurality of print head element s, printing the pixel on thermal print medium; and determine a voltage pulse pattern for printing the tri-color tuple at the input temperature based on a previously printed pixel.

Abstract: In some examples, luminance-biased sharpening for thermal media printing may include converting an input image to a grayscale luminance representation. For each pixel of a plurality of specified pixels of the converted input image, a sharpening lightness value may be determined. Further, for each pixel of the plurality of specified pixels of the converted input image, a ratio of the sharpening lightness value to a corresponding original lightness value may be determined. Based on the determined ratio, a sharpened output image corresponding to the input image may be generated.

Abstract: Color values are measured for a set of color targets printed by a reference printing device on a medium of a reference media type. A different printing device prints a subset of the set of color targets on another medium of this reference media type. The color values of the subset of color targets printed by the different printing device are measured, and the different device calibrated based on the measured color values for both the set that the reference printing device printed and the subset that the different device printed. The different printing device can then also be calibrated for a different media type, based on a transformation of the set of color targets printed by the reference printing device on a medium of the different media type relative to the set of color targets printed by the reference device on the medium of the reference media type.

Abstract: A transform wrapper is stored on a memory device and the memory device may be included in a printer cartridge. The transform wrapper may dynamically build a transform map for a printer based on metadata stored at the memory device. The metadata may indicate at least one of a type of depositing material, transform map, print media and printer.

Abstract: In some examples, with respect to three-dimensional printer color management, three-dimensional printer native space coordinates of a three-dimensional printer may be mapped to three-dimensional printer printing agent space coordinates of the three-dimensional printer. The three-dimensional printer printing agent space coordinates may be mapped to color space coordinates. The color space coordinates may be mapped to two-dimensional printer printing agent space coordinates of a two-dimensional printer. The two-dimensional printer printing agent space coordinates may be mapped to two-dimensional printer native space coordinates of the two-dimensional printer. A color management protocol of the two-dimensional printer may be utilized, based on the mapping of the three-dimensional printer native space coordinates to the two-dimensional printer native space coordinates, for the three-dimensional printer to print a three-dimensional object.

Abstract: A transform wrapper is stored on a memory device and the memory device may be included in a printer cartridge. The transform wrapper may dynamically build a transform map for a printer based on metadata stored at the memory device. The metadata may indicate at least one of a type of depositing material, transform map, print media and printer.

Abstract: A transform wrapper is stored on a memory device and the memory device may be included in a printer cartridge. The transform wrapper may dynamically build a transform map for a printer based on metadata stored at the memory device. The metadata may indicate at least one of a type of depositing material, transform map, print media and printer.

Abstract: A transform wrapper is stored on a memory device and the memory device may be included in a printer cartridge. The transform wrapper may dynamically build a transform map for a printer based on metadata stored at the memory device. The metadata may indicate at least one of a type of depositing material, transform map, print media and printer.

Abstract: A device includes memory and a processor connected to the memory to execute instructions. The instructions are to determine luminance values of pixels of an original image and to determine chrominance values of pixels of a processed image obtained from performance of an image processing operation on the original image. The instructions are further to combine the luminance values of the pixels of the original image and the chrominance values of the pixels of the processed image to obtain a resultant image.

Abstract: Certain examples described herein relate to the preprocessing of object data for the manufacture of a three-dimensional object. In one case, the object data represents at least a first and a second object portion, the first object portion being associated with a first production material composition and the second object portion being associated with a second production material composition. The first and the second object portions may be arranged such that they comprise a contiguous interface. In certain described cases, the object data is modified by modulating the contiguous interface. Said modulating the contiguous interface may comprise modulating data defining at least one of the first and the second object parts such that a portion of at least one of the first and second production material compositions extends into object space occupied by a respective one of the second and first object parts. The resultant modified object data may be used to manufacture the three-dimensional object.

Abstract: In some examples, a print cartridge includes a memory device comprising quantized coefficients derived from a lossy compression, at a selected step size, of a difference color table including a plurality of difference nodes in which each difference node represents a difference value that is a difference of a value of a node of a color table and a value of a corresponding node of a reference table, the quantized coefficients useable to produce a reconstructed difference color table including a first set of difference nodes each representing a difference value that is within an error threshold at the selected step size, and a second set of difference nodes each representing a difference value that is outside an error threshold at the selected step size. The memory device further comprises corrective information to correct the second set of difference nodes of the reconstructed difference color table.

Abstract: According to examples, area coverage vectors for each pixel on each slice of a digital representation of an object may be determined and a two-dimensional halftone matrix including threshold values may be subdivided into a plurality of sub-matrices, each sub-matrix including threshold values of the halftone matrix in a respective value sub-range. In addition, for each of the slices, a sub-matrix of the plurality of sub-matrices may be selected and the area coverage vectors for the pixels in the slice may be halftoned using respective threshold values of the selected sub-matrix.

Abstract: In some examples, luminance-biased sharpening for thermal media printing may include converting an input image to a grayscale luminance representation. For each pixel of a plurality of specified pixels of the converted input image, a sharpening lightness value may be determined. Further, for each pixel of the plurality of specified pixels of the converted input image, a ratio of the sharpening lightness value to a corresponding original lightness value may be determined. Based on the determined ratio, a sharpened output image corresponding to the input image may be generated.

Abstract: In some examples, dynamic threshold based error diffusion may include determining whether a pixel associated with a pattern to be printed includes a lighter tone or a darker tone compared to an adjacent pixel. In response to a determination that the pixel associated with the pattern to be printed includes the lighter tone or the darker tone compared to the adjacent pixel, a firing threshold may be respectively increased or decreased to respectively decrease or increase a likelihood of printing of the pattern.

Abstract: A memory device includes a compressed color table and corrective information. The compressed color table includes a first set of nodes of the color table compressed with a lossy compression at a selected compression ratio. The first set of nodes include a color difference within an error threshold at the selected compression ratio. Corrective information is included for a second set of nodes of the color table. The second set of nodes have a color difference outside the error threshold.

Abstract: In some examples, dynamic threshold based error diffusion may include determining whether a pixel associated with a pattern to be printed includes a lighter tone or a darker tone compared to an adjacent pixel. In response to a determination that the pixel associated with the pattern to be printed includes the lighter tone or the darker tone compared to the adjacent pixel, a firing threshold may be respectively increased or decreased to respectively decrease or increase a likelihood of printing of the pattern.