Multilevel screening mapping tone values to control signal values for greater color or shade fidelity and reduced print aberrations
US7969617B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 4, 2008 |
| Grant date | Jun 28, 2011 |
| Priority date | — |
| Expiry date | Jan 16, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/52
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of producing a printed output on a substrate is provided using a drop emitting device which is adapted to emit a plurality of ink quantities in response to a control signal. The method comprises the steps of receiving image data corresponding to a pixel of an image to be printed, the received image data comprising a tone value; generating a threshold value for use in a screening operation based on the location of the pixel within the image to be printed; mapping the received tone value to a mapped tone value using a first tone mapping, the mapped tone value being generated based on the received tone value; performing the screening operation by comparing the mapped tone value with the threshold value; mapping the received tone value to a control signal value using a first control mapping if the output of the comparison performed in the previous step indicates a first relationship, the control signal value being generated based on the received tone value; and repeating the previous three steps if the output of the comparison performed in the previous step indicates a second relationship, wherein the first mapping step comprises using an alternate tone mapping and the second …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.