Contour emphasizing circuit
US7321401B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 2005 |
| Grant date | Jan 22, 2008 |
| Priority date | — |
| Expiry date | Jul 20, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/208
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A contour emphasizing circuit which comprises a contour pick-up unit 10 for picking up a contour component HE from an input luminance signal Y, a level judging unit 15 for judging the luminance level of the input luminance signal Y, a coefficient control unit 17 for changing the coefficient in a plurality of steps depending upon a judgment signal and multiplying the contour component HE by the coefficient to output the product, and an adder 14 for adding the contour component outputted from the coefficient control unit 17 to the input luminance signal Y to output an emphasized-contour luminance signal. The coefficient to be multiplied by the contour component HE is changed in a plurality of steps depending upon the luminance level of the input luminance signal Y, and the contour component HE to be added to the input luminance signal Y is controlled to have a magnitude appropriate to the luminance level of the input luminance signal Y. As a result, the contour is emphasized according to the luminance level of the input luminance signal Y without causing excessive contour emphasis by adding a large contour component to a dark image of a small luminance level, thus preventing formatio…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.