Adaptive control signal generator for an adaptive luminance/chrominance separator
US5231478A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 26, 1991 |
| Grant date | Jul 27, 1993 |
| Priority date | — |
| Expiry date | Dec 26, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/78
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An apparatus and method for producing improved adaptive control signals for a luminance and chrominance separation circuit employing adaptive filtering of a chrominance signal includes a vertical difference detector, a horizontal difference detector, and a combiner. The vertical difference detector contains upper difference detector and lower difference detector, each of which receives a horizontally filtered next line signal (L.sub.N), a horizontally filtered present line signal (L.sub.P), and a horizontally filtered last line signal (L.sub.L), and which produce, respectively, an upper difference signal and a lower difference signal. In a preferred embodiment, the lower and upper difference detectors implement, respectively, the expressions .vertline.2L.sub.L +L.sub.P -L.sub.N .vertline. and .vertline.2L.sub.N +L.sub.P -L.sub.L .vertline.. The vertical detector also contains a larger valve selector that receives the upper and lower difference signals and produces a vertical chrominance difference signal that is based on, and preferably is the larger of the upper and lower difference signals. The horizontal difference detector receives the present line signal and determines the abs…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.