Circuit for generating a digital, deleted data, blinking cross signal which is stored in a deleted track and selectively displayed for detection
US4130842A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 4, 1977 |
| Grant date | Dec 19, 1978 |
| Priority date | — |
| Expiry date | Feb 4, 1997 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/214
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A circuit for generating a deleted data signal, which is reproduced as a blinking cross in a television picture, to provide thereby visual indication that a storage location in a video frame store is unoccupied, and available for recording therein. The blinking effect is created by interlacing one diagonal line generated in one field with an opposing diagonal line generated in a second field at the 30 Hertz frame rate. The deleted data signal corresponding to the blinking cross is recorded in the deleted track, e.g., the still location thereof, whereby the store can be interrogated and the deleted data signal suitably displayed to indicate the availability and location of the track for subsequent recording.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.