Image-reproduction apparatus
US4346402A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 28, 1980 |
| Grant date | Aug 24, 1982 |
| Priority date | — |
| Expiry date | May 28, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/6025
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A color scanner for the graphic arts of the kind in which three uncorrected color-component analogue signals from the scanner are converted into digital form and are applied to the inputs of a three-dimensional look-up table or read-only memory in which are stored corresponding color-corrected signal values for the three colors and, if desired, for black. Individual one-dimensional color-component look-up tables are interposed between the analogue-digital converter and the three-dimensional look-up table. The functions performed by the one-dimensional tables may include logarithmic conversion of the input signals, for example. Preferably, further individual one-dimensional look-up tables are inserted between the outputs of the three-dimensional table and a digital-analogue converter preceding an output scanner.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.