Digital video generator
US4849746A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 7, 1986 |
| Grant date | Jul 18, 1989 |
| Priority date | — |
| Expiry date | Apr 7, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/2222
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A digital video generator provides for smooth scrolling of a video image across a video display device. A digital memory contains data to be displayed. Under control of a computer this data is transferred to a display memory as needed. The data is displayed with a gray scale intensity level for each pixel. Two successive pixels in the direction of movement are read out of the display memory, a current pixel and a next pixel, and are added together in a mixer with a weighting factor determined by the computer according to the scrolling speed selected to provide a weighted pixel. The weighted pixel is converted into analog video data or display. At intervals depending upon the selected scrolling speed the computer reloads the display memory from the digital memory to replace the data which has been displayed and scrolled off the monitor. Initial values for the top of the display field and the weighting factor are computed each display cycle. The result is the appearance of smooth partial pixel movement for each display cycle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.