Automated encoded signal color image compositing
US4589013A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 13, 1983 |
| Grant date | May 13, 1986 |
| Priority date | — |
| Expiry date | Jun 13, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/75
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus to cause a colored backing to be replaced by a background scene, such that the composite scene shows no loss of detail, no edge anomalies, no evidence of a colored backing having been present, and no evidence that the final scene is a composite, even when the foreground scene contains fine strands of hair, glassware, smoke, fog, or other semitransparent subjects. Control signals E.sub.b and E.sub.c are created to cause the foreground and background scenes to mutually interact in a natural manner, so that shadows on the colored backing appear as shadows on the background scene, and the luminance of the background selectively causes back and edge lighting of foreground subjects. The hue and luminance of the colored backing are continuously and automatically tracked and removed by a subtraction process. The background level is automatically held constant even though backing illumination changes. Hue and luminance removal and background level are controlled by comparators (35,36) and digital counters (39,40). Levels set by the automatic circuits are retained when the camera pans off of the (blue) backing. No disturbance occurs to the picture when the camera retur…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.