Fading of main video signal without affecting display of superimposed video signal
US6587155B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 27, 1999 |
| Grant date | Jul 1, 2003 |
| Priority date | — |
| Expiry date | Dec 27, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/85
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A fade circuit adjusts the luma as well as one or more chroma components of a main video so that the fade ins and fade outs of the main video do not change the color of an on-screen display image, such as the volume bar. In one embodiment, luma component (Y) is adjusted by subtracting a fade factor from the luma component to form a faded luma component. At the same time, one or more chroma components (Cb and Cr) are scaled by (1) subtracting a predetermined value from the chroma component to form a resultant, (2) multiplying the resultant with a scale factor to form a product, and (3) adding the predetermined value to the product to form a faded chroma component.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.