Chroma keyer with correction for background defects
US5400081A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 15, 1994 |
| Grant date | Mar 21, 1995 |
| Priority date | — |
| Expiry date | Feb 15, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/75
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A chroma keyer with correction for background defects generates a control signal that does not include variations associated with the background defects. The chroma magnitude of a reference signal that represents a chroma key set with a color background scene without a foreground object is used as a divisor for a hue select signal generated by a hue selector from a chrominance component of an input signal that represents the chroma key set with the foreground object to produce a chroma key control signal. The chroma key control signal is combined with the reference signal to produce a control signal for background suppression. The chroma key control signal also is input to a key circuit to produce a key signal for shaping a new background scene. The reference signal also may be combined with a uniform color signal from a reference matte generator to produce an error signal that is combined with the chroma key control signal to produce the control signal for correction of the background defects in the input signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.