Hewlett-packard Development Company, L.p.

Digital Equipment Corporation

Compaq Computer Corporation, Inc.

Purdue Research Foundation

Other

Compaq Information Technologies Group, L.p.

Robert Alan Ulichney

Matthew Donald Gaubatz

Steven J Simske

Stephen Bernard Pollard

Shiufun Cheung

Robert MacNamara

Giridharan Iyengar

Jan Philip Allebach

Robert Stephen McNamara

Daniel R Tretter

Niranjan Damera-Venkata

Utpal Kumar Sarkar

Lluis Abello Rosello

Himanshu Arora

Sing Bing Kang

William James Allen

Jason S Aronoff

Ingeborg Tastl

Andrew E Fitzhugh

Joan Vidal Fortia

John Ludd Recker

Tal Frank

Shivaun Albright

Frederic Dufaux

Rahul Sukthankar

Yotam Ben-Shoshan

William Hallahan

Yafei Mao

Sekhar Muni Sirigiri

Patrick D Charles

Greg S Smith, Jr

Wanling Jiang

Altyngul Jumabayeva

Paramvir Bahl

David Rouse

Christopher J Cheng

Ruiyi Mao

Stephen Pollard

A method of forming a data-hiding watermark on a surface may include encoding data within an image using the chrominance data of the of the image, adjusting at least one characteristic of the image to enhance the prominence of the encoded data within the image, and printing the adjusted, encoded image onto the surface.

Encoded monochrome images of data-hiding watermarks

In an example method, a first dot pattern of shadow dots and second dot pattern of highlight dots is generated. The first dot pattern and second dot pattern include information to be encoded across the image. The first dot pattern and the second dot pattern are mapped to a corresponding subset of the greyscale source pixels, the greyscale source pixels corresponding to an image to be printed. A value of a greyscale pixel in the subset of the greyscale source pixels is modified based on a predetermined threshold pixel value. The value of the greyscale pixel is set to a highlight dot value in response to detecting that the predetermined threshold pixel value is exceeded or set to a shadow dot value in response to detecting that the predetermined threshold value is not exceeded. The image including the subset of pixels with modified values is printed.

Encoding information using disjoint highlight and shadow dot patterns

Examples disclosed herein relate to determining image capture position information based on a quasi-periodic pattern. For example, a processor may determine whether a target area is within a captured image based on the detection of a quasi-periodic pattern in a first detection area and in a second detection area of the captured image.

Determine image capture position information based on a quasi-periodic pattern

According to an example, density rank matrix normalization for three dimensional printing may include receiving a density rank matrix. The density rank matrix may include elements that include rank values, and the rank values may specify an order by which a voxel is to be turned on to generate an output object. A normalization specification of maximum and minimum structure sizes for structures that are to form the output object may be received. Further, each of the rank values may be converted, according to the normalization specification, to a corresponding threshold value to generate a density threshold matrix.

Density rank matrix normalization for three-dimensional printing

One example includes a three-dimensional (3D) printed object including a first lattice structure and a second lattice structure. The first lattice structure includes a first matrix having a first length, a first width, and a first height. The second lattice structure includes a second matrix having a second length, a second width, and a second height. The second length times two is a factor of the first length, the second width times two is a factor of the first width, and the second height times two is a factor of the first height.

Multiscale density threshold matrices for 3D printing

A data-bearing medium is disclosed. The data-bearing medium includes a section of cells having a set of opposite-shifted clusters. The cells include a combination of opposite shifts of the set of opposite-shifted clusters, which represent a single value.

Data-bearing medium

An example system in accordance with an aspect of the present disclosure includes a halftone engine and a gray value engine. The halftone engine is to apply halftoning to an image recursively across a plurality of levels of image scales and spatial resolutions, to generate a pattern that is at least quasi-periodic across the plurality of levels. The gray value engine is to substitute gray values recursively for at least a portion of the halftoning.

Recursive halftoning and gray value substitution

In an example method, a set of source pixels corresponding to an image to be printed and a dot pattern of pixels including information to be encoded across the image are received. The dot pattern of pixels is mapped to a corresponding subset of the source pixels. A value of a clipping channel color in the subset of the source pixels is modified based on an original value of the clipping channel color for each pixel in the subset. The clipping channel color is used to detect the dot pattern of pixels. The image including the subset of pixels with modified clipping channel colors is printed.

Encoding dot patterns into printed images based on source pixel color

According to an example, density rank matrix generation for three-dimensional printing may include determining dimensions of a density rank matrix based on a skeleton line specification of a lattice structure and a density rank matrix size specification. A number of elements of the density rank matrix may be determined based on the dimensions of the density rank matrix. The elements may be sorted based on an analysis of a property of each of the elements relative to the lattice structure. The density rank matrix may be generated based on the sorting of the elements.

Density rank matrix generation for three-dimensional printing

An omnidirectional barcode may include a graphical representation of a one-dimensional barcode wherein the graphical representation of the one-dimensional barcode is extended circumferentially around a three-dimensional (3D) object. A method of forming an omnidirectional barcode may include creating a graphical representation of a one-dimensional barcode and extending the one-dimensional representation in at least one dimension.

Omnidirectional barcode

An example system to represent data with multi-dimensional cyclic symbols is provided. The system includes a representation engine, a symbol engine, and a translation engine. The representation engine is to provide a plurality of display symbols. Display symbols are selected from a set of multi-dimensional cyclic symbols. The symbol engine is to receive a plurality of received symbols. The translation engine is to convert the plurality of received symbols into a plurality of display symbols.

Multi-dimensional cyclic symbols

An example method is described in which a processor receives a first plurality of symbols selected from a first set of symbols, translates the first plurality of symbols into a second plurality of symbols selected from an M-ary cyclic symbol set, and writes the second plurality of symbols to a surface. An additional example method is described in which a processor captures an image of at least a portion of a surface, detects a first plurality of symbols from the image, where the first plurality of symbols comprises symbols selected from an M-ary cyclic symbol set, translates the first plurality of symbols into a second plurality of symbols selected from a second set of symbols, and performs at least one task responsive to the second plurality of symbols.

M-ary cyclic coding

In an example method, a dot pattern of pixels including information to be encoded across an image is mapped to a corresponding subset of the grayscale source pixels corresponding to the image to be printed. A value of a grayscale pixel in the subset of the grayscale source pixels is modified based on based on a predetermined threshold pixel value. The value of the grayscale pixel is decreased in response to detecting that the predetermined threshold pixel value is exceeded. The clipping channel color is used to detect the dot pattern of pixels. The image including the subset of pixels with modified values is printed.

Encoding information in printed images by decreasing grayscale pixel values exceeding threshold

In some examples, an imaging device may include a controller including processing circuitry to detect, a first quantity of rows of pixels to be included as a first band of a contone image, process the pixels of each row of the first band in parallel raster order, detect a second quantity of rows of pixels to be included as a second band of the contone image; and process the pixels of each row of the second band in response to the completion of the pixels of the first band, where the rows of the second band are processed in parallel in serpentine order with respect to the first band.

Parallel image processes

Growing community of inventors

Marlborough, MA, United States of America

Robert Alan Ulichney