Image filing method
US5068745A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 29, 1990 |
| Grant date | Nov 26, 1991 |
| Priority date | — |
| Expiry date | Mar 29, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/2166
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Image signals are subjected to a first signal compression processing which is carried out with a small factor of compression. The compressed image signals, which are obtained from the first signal compression processing, are recorded on a first recording medium. When a predetermined period has elapsed after a compressed image signal obtained from the first signal compression processing was recorded on the first recording medium, or when the frequency with which the compressed image signal is read from the first recording medium has become lower than a predetermined value, the compressed image signal is read out from the first recording medium. The image signal, which has been read out from the first recording medium, is subjected to a second signal compression processing which is carried out with a large factor of compression. The compressed image signal, which is obtained from the second signal compression processing, is recorded on a second recording medium. Thereafter, the compressed image signal, for which the predetermined period has elapsed after it was recorded on the first recording medium or for which the frequency has become lower than the predetermined value, is erased f…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.