Real-time conversion of still-video to half-tone for hard copy output (such as on a facsimile machine)
US5193012A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 29, 1991 |
| Grant date | Mar 9, 1993 |
| Priority date | — |
| Expiry date | Apr 29, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/0067
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A real-time still-video to facsimile conversion system (FIG. 3) converts a still-video image frame into a half-tone facsimile reproduction without having to store an entire intermediated grey-scale image frame. Conversion of a still-video image to a half-tone facsimile output is accomplished by repeatedly transmitting the still-video image frame from a still-video source to a still-video input circuit (10), with a virtual facsimile page synchronization module (20) providing synchronization to a virtual facsimile page. In successive image frames, a video pixel grabber (34) grabs successive columns of image pixels, and provides them to a half-tone pixel converter (32) for conversion to facsimile lines--for the exemplary embodiment a 3.times.3 half-tone pixel format is used, so that the 525 raster lines of an image pixel column are transformed into three facsimile lines using a total of 1575 dots per line (out of the standard 1728 dot facsimile line). After conversion of each column of image pixels, the corresponding facsimile lines are buffered in a facsimile multi-line buffer (36) for conventional facsimile transmission by a half-tone facsimile output module (40) to a facsimile mach…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.