Apparatus for transmission of chrominance signals during blanking period
US4084181A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 21, 1977 |
| Grant date | Apr 11, 1978 |
| Priority date | — |
| Expiry date | Jan 21, 1997 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/81
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A color television signal processing apparatus is provided for reproducing a chrominance signal from a color television signal transmitted or recorded in such a manner that the chrominance signal is compressed in time scale and that the compressed chrominance signal is superposed on the horizontal blanking period signal of the color television signal in a time division manner. This apparatus includes a circuit for generating a clock pulse used for expanding the time scale of the compressed chrominance signal comprising a signal generator driven by a sample pulse derived from a reference signal in a color television signal and producing low and high frequency signals, a reset pulse generating circuit which compares a reference reset pulse derived from the reference signal with a comparison reset pulse generated from selfoscillating circuit, and a clock pulse generator driven by the output signals of the signal generator and the reset pulse generator. In this way, a correct clock pulse which may be used for expanding the compressed chrominance signal is obtained even when the reference signal in the color television signal temporarily disappears.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.