Method and apparatus for reproducing an original gray scale image
US4210936A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 27, 1977 |
| Grant date | Jul 1, 1980 |
| Priority date | — |
| Expiry date | Dec 27, 1997 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/4051
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus are disclosed for reproducing an original gray scale image that may be divided into an array of discrete picture elements. The method comprises the steps of scanning each of the picture elements in the array on the original image to determine its gray level and location in the array and generating sequential signals that contain data indicative of the gray level and location in the array of each of the scanned picture elements. The gray level of the entire array is calculated from the data on each of its individual picture elements in accordance with a gray scale function. On a reproduction medium in an array of reproduction locations corresponding to the picture element array, locations are sequentially darkened in order of decreasing gray level, beginning at the location that corresponds to the scanned picture element having the darkest gray level, until the gray level of the reproduction array substantially equals the calculated gray level of the scanned picture element array. Therefore, the gray level distribution of the picture element array is substantially duplicated on the reproduction array to provide maximum resolution within the capability of the s…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.