Image contour enhancing apparatus which limits enhancement where signal components for contour enhancement in both horizontal and vertical directions are generated in overlapping relationship
US5432563A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 27, 1994 |
| Grant date | Jul 11, 1995 |
| Priority date | — |
| Expiry date | Jun 27, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/208
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image contour enhancing apparatus capable of minimizing excessive enhancement of the image contour in an image area where both a horizontal contour enhancing signal and a vertical contour enhancing signal are generated in overlapping relation. In the image contour enhancing apparatus, an image contour enhancing signal produced by deriving a horizontal contour enhancing signal from a video input signal by a high-pass filter, deriving a vertical contour enhancing signal from the video input signal by another high-pass filter and by adding these contour enhancing signals is added by an adder to the video input signal to improve the sharpness of the image contour, and circuits are provided for making variable the signal level of the image contour enhancing signal in the image area where both the horizontal and vertical contour enhancing signals are generated in overlapping relation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.