Hewlett-packard Development Company, L.p.

Hewlett-packard Company

Other

Purdue Research Foundation

Jay Stephen Gondek

Jefferson Patrick Ward

Stephen J Nichols

Morgan Thomas Schramm

Jan Morovic

Peter Morovic

Jason M Quintana

Matthew Allen Shepherd

Jan Philip Allebach

Ranjit Bhaskar

Kevin R Hudson

Amy Ruth Reibman

Mark Q Shaw

Steven O Miller

Chuohao Tang

Sean Michael Collison

Thomas Berge

Alexey S Kabalnov

Charles Addison Bouman

Brian J Atkins

William James Allen

Kent E Biggs

Juan Manuel Garcia Reyero Vinas

Thomas B Pritchard

Charles G Dupuy

John F Meyer

Miguel Angel Lopez Alvarez

Milan Justel

Je-Ho Lee

Frank W Sliz

Otto Kenneth Sievert

Stephen William Bauer

Thomas J Flynn

Guo Li

Weiyun Sun

Philip Cowan

C Brian Atkins

Hsue-Yang Liu

Luanne J Rolly

Xin Cheng

David Walter Childs

Philip B Cowan

Jeho Lee

Woonyoung Jang

Julie Hong Ouyang

Soda Heng

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.

Transform map at printer cartridge

Example implementations relate to adjust sharpness parameters. 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 comprising color channels corresponding to print pixels to be formed on a multi-layer thermally activated print medium, determine a characteristic of a corresponding layer of the multi-layer thermally activated print medium for color channels of the received print data, adjust sharpness parameters of the color channels based on the determined characteristic of the corresponding layer of the multi-layer thermally activated print medium, and cause a print head of the printing device to apply thermal energy to an area of the multi-layer thermally activated print medium including the print pixels using the adjusted sharpness parameters.

Adjust sharpness parameters

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.

Three-dimensional printer color management

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.

Printing system calibration using reference printing device

In some examples, dithering based color conversion may include ascertaining an input color value. Based on conversion of the input color value to an output color space representation, a set of nodes that are to be analyzed to control operation of a printer may be determined. Based on a position of the input color value from each node of the set of nodes, a corresponding probability associated with each node of the set of nodes may be determined. Further, the operation of the printer may be controlled based on the determined probability associated with each node of the set of nodes.

Dithering based color conversion

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.

Alignments of media using multiple passes

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, a ratio of the sharpening lightness value to a corresponding original lightness value may be determined. A resulting sharpened pixel may be determined by applying a corresponding value of the determined ratio to each of the specified pixels. A dark correction factor may be applied to the resulting sharpened pixels that are darkened and a light correction factor may be applied to the resulting sharpened pixels that are lightened. Based on application of the dark correction factor and the light correction factor, a sharpened output image corresponding to the input image may be generated.

Luminance-biased sharpening for thermal media printing

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.

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.

Processing object part data for a three-dimensionsal object

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.

Color table compression

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.

Three-dimensional halftoning area coverage vectors for pixels in each slice of object using selected sub-matrix

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.

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Camas, WA, United States of America

Jay Stephen Gondek