Knee correction
US5729299A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 14, 1995 |
| Grant date | Mar 17, 1998 |
| Priority date | — |
| Expiry date | Apr 14, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/68
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A knee circuit in which the hue on the output side does not differ from the hue on the input side. The knee circuit includes a virtual luminance signal generator for generating a virtual luminance signal Y based on at least one input color signal Rin, Gin and Bin, a virtual correction value generator for monitoring whether the virtual luminance signal Y is equal to or greater than a knee point NP and for generating a virtual correction value Yk by performing a knee correction with respect to the virtual luminance signal Y when it is equal to or greater than the knee point NP. A proportional value generator generates a proportional value Kk showing a ratio of the virtual correction value Yk to the virtual luminance signal Y by dividing the virtual correction value Yk by the virtual luminance signal Y. A correction color signal generator multiplies each of the input color signals Rin, Gin and Bin by the proportional value and outputs a multiplication result as corrected color signals Rout, Gout and Bout, that is, color signals on which knee correction has been performed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.