Circuit for and method of detecting a color field sequence of a color video signal
US5012327A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 9, 1988 |
| Grant date | Apr 30, 1991 |
| Priority date | — |
| Expiry date | Sep 9, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N17/02
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A color field 1 detector includes analog and digital processor sections, wherein the analog processor section receives a video signal input and provides the digital signals necessary to drive the digital processor section. A timing generator receives a free-running reference clock and supplies an internal reference signal of subcarrier frequency starting at the falling edge of composite sync. A burst phase comparator compares the incoming color burst phase to the internal reference signal phase and generates logic signals indicative of the phase relationships therebetween to thus indicate whether the color burst is in phase, 180.degree. out of phase, or if any phase error exists. A state machine receives the logic signals and detects the sequence of occurrence of the states of the color burst relative to the internal reference signal. The sequence is indicative of the subcarrier-to-composite sync phase of the video signal input for the particular color television standard. The state machine provides a field reference signal in the form of a selected logic level which identifies the color field 1 of the color field sequence for the standard.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.