Method and device for recreation of an analog luminance signal from a digital signal
US4670792A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 7, 1982 |
| Grant date | Jun 2, 1987 |
| Priority date | — |
| Expiry date | May 7, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/40068
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention concerns a process for the recreation of an analog luminance signal from a digital signal used for transmission after analog digital conversion of a luminance signal representative of a document to be transmitted, consisting in taking into consideration, before or after the D-A conversion of the reception, a number P of successive pixels P-2, P-1, P, P+1, p+2 and, as a function of their relative and absolute amplitudes, in processing the central pixel P, breaking it down into m sub-pixels having densities that are a function of those of the surrounding pixels. The present invention notably applies to the digital transmission of iconographic documents transmitted and received by a method of the "Belin" type.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.