Hewlett-Packard Development Company, L.p.

Hewlett-Packard Company

Lluis Abello

Mike Steed

Steven J Simske

Paolo Faraboschi

Roland John Burns

Andrew Mackenzie

Emiliano Bartolome

Manuel Gonzalez

Jorge Martinez De Salinas Vazquez

Ronald J Burns

Andreu Gonzalez

Albert Serra

Joan Vidal, Jr

Virginia Palacios

A number of colors in a predefined region of an image to be compressed are determined. The predefined region has a plurality of pixels. In response to determining that the number of colors is greater than a first predefined threshold, a lossy compression process is selected dependent on a number of pixels in the predefined region having a predefined color. The selected lossy compression process is applied to the predefined region.

Image compression

A method of recirculating fluid in a printhead die is provided. The recirculation is performed for at least one nozzle, such that the recirculation finishes before the corresponding at least one nozzle completed ejection of a drop.

Printhead recirculation

In some examples herein, control data is for application of treatment fluid on a treatment substrate location surrounding a substrate dot corresponding to a first pixel of the digital image. Treatment fluid is ejected on the treatment substrate location if a metric value computed from pixel values of a set of pixels in the neighborhood of the first pixel is above a threshold level.

Control of printing systems to apply treatment

A page-wide array inkjet printer allocates the processing tasks for individual printheads within the array to separate halftoning processors. Each halftoning processor processes the information relating to a strip of the image, with the boundaries between strips running parallel to the print medium advance direction. In a preferred embodiment, the pixels within each strip are processed using a forward error diffusion algorithm operating along columns of pixels parallel to the strip boundaries. The resulting halftone data is supplied from each halftoning processor to one or more uniquely associated printing component controllers, and these controllers generate print instructions for printing components (e.g. inkjet printheads) connected to the printing component controllers via a dedicated communications channel.

Printing image slices in parallel by print engines

Methods and means for imaging on paper media are provided. A data file of an image to be printed is analyzed. A pattern for a clear fluid is determined according to the analysis. The pattern of clear fluid is applied to a paper media traveling in a particular direction, wherein the pattern is generally elongated along the direction of travel. The pattern of clear fluid is defined by a maximum width that is generally equal to the maximum width of the image to be formed. One or more colored inks are applied such that the image is formed and is supported by the paper media. The paper media exhibits reduced cockle as a result of the pattern of clear fluid.

Clear fluid patterning on paper media

A method and apparatus for producing a document having human-readable content and a position identifying encoding pattern. A printer places text or other content onto a substrate, such as paper, and a filter material application system applies transparent filter material to at least a portion of that content to only modify the reflectivity of the content at a predetermined wavelength. Because the reflectivity of the position identifying encoding pattern remains unchanged, it is distinguishable from the content and can be read at the predetermined wavelength. The position identifying pattern can take a number of forms including a number of dots printed at predetermined positions on the substrate on an imaginary grid.

Products with data-encoding pattern

A method of halftoning monochrome contone image data with a color pixel processor, the processor being arranged to halftone substantially simultaneously a plurality of image data corresponding to a plurality of different colors, the method comprising the step of: halftoning substantially simultaneously a plurality of monochrome image data corresponding to a plurality of separate pixel positions of a print job.

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Tarragona, Spain

Lluis Abello