Method of detecting boundary structures in a video signal
US4896364A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 1, 1986 |
| Grant date | Jan 23, 1990 |
| Priority date | — |
| Expiry date | Dec 1, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/10016
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of detecting edge structures in a video signal, with a decision criterion being derived from the environment pixels of an image pixel so as to realize image coding with the least number of bits possible. The object of detecting all of the oblique edges i.e. edges which are not horizontal or vertical, is accomplished in that an average is formed from the environment pixels of an image pixel and this average is then compared with each environment pixel so as to obtain an output signal having one of three-values (1, 0, -1) dependiing on whether the luminance or chrominance values of the particular environment pixel is above, within or below a given tolerance range. A conclusion as to the existence of an edge and its orientation is then drawn from the number of immediately consecutive identical positive or negative values (1 or -1) of this possible three-valued signal for an image pixel and from the position of the changes in value within the sequence of environment pixels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.