Methods and apparatuses for printer calibration
AssigneeDigimarc Corporation
InventorAlastair M. Reed
Life of this patent
Estimating the term…
Abstract
A test pattern printed by a printer is assessed—without colorimetric equipment—to provide data used in recalibrating the printer. The assessment may be made by an unskilled operator, and can include discerning whether a particular pattern is visible in the printed test pattern, or whether a feature in the test pattern is relatively wider or narrower. From such assessment, needed changes to the printer's calibration data are inferred and implemented. A variety of other printer calibration techniques are disclosed. The technology is illustrated in the context of dye sublimation printers, and is particularly useful in optimizing printing of digitally-watermarked graphics.
Claims27
A method of calibrating the method comprising:
- instructing a printer to print a test graphic comprised of features, wherein each feature has a different tone value;
- receiving data based on an assessment of the appearance of the test graphic, as actually printed;
- and
- changing a tonal compensation parameter of the printer based on the received data;
- wherein the received data relates to a width dimension of one or more of the features.
A method of calibrating, the method comprising:
- printing, with a printer, a test pattern, the test pattern including a first visible feature that spans a plurality of pixels in both width and height;
- assessing a width of the first visible feature;
- and
- modifying a tonal compensation parameter of the printer based on the assessment.
A method of calibrating, the method comprising:
- printing, with a printer, a test pattern;
- receiving data indicating one of two possible and opposite assessments concerning the printed test pattern;
- making a first rote change to a tonal compensation parameter of the printer if the received data indicates a first of the assessments;
- and
- making a second, different, rote change to the tonal compensation parameter if the received data indicates a second of the assessments.
A method comprising:
- printing, with a printer, a test pattern comprising a plurality of patches, each patch being defined by a unique combination of colorant data signals;
- receiving an indication of which patch appears to most closely match a reference color;
- and
- modifying a tonal compensation parameter based on the indication;
- wherein certain ones of the plurality of patches are defined by unique combinations of three different colorant signals.
A method comprising:
- instructing a printer to print a test graphic comprised of elements that should differ slightly in tone value;
- receiving, from a sensor of the printer, data based on a difference between the visual appearance of a first and second of the elements, as actually printed;
- and
- changing a tonal compensation parameter of the printer based on the received data.
A method comprising:
- printing, with a printing apparatus, a test pattern comprising a plurality of patches, each patch being defined by a unique combination of colorant data signals;
- receiving an indication of which patch appears to most closely match a reference color;
- and
- modifying a tonal compensation parameter based on the indication;
- wherein the plurality of patches comprises three patches having different values of a first colorant data signal, and three patches having different values of a second colorant data signal.
An apparatus for calibration, the apparatus comprising:
- a processor configured to:
- instruct a printer to print a test graphic comprised of features, wherein each feature has a different tone value;
- receive data based on an assessment of the appearance of the test graphic, as actually printed;
- and
- change a tonal compensation parameter of the printer based on the received data;
- wherein the received data relates to a width dimension of one or more of the features.
A non-transitory computer-readable storage medium having instructions stored thereon that, if executed by a computing device, cause the computing device to perform operations comprising:
- instructing a printer to print a test graphic comprised of features, wherein each feature has a different tone value;
- receiving data based on an assessment of the appearance of the test graphic, as actually printed;
- and
- changing a tonal compensation parameter of the printer based on the received data;
- wherein the received data relates to a width dimension of one or more of the features.
Dependencies are inferred from the claim text.