Circuit and method for live switching of digital video programs containing embedded audio data
US7023488B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 2002 |
| Grant date | Apr 4, 2006 |
| Priority date | — |
| Expiry date | Jun 21, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/44016
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A circuit for detecting a transition in the content of a digital video stream containing embedded audio samples and providing a smooth transition from an old audio stream embedded before the transition to a new audio stream embedded after the transition. The circuit detects the transistion and in response it fades out the old audio stream and fades in the new audio stream. During the transition, the old and new audio signal are buffered. The old stream is not faded out until only a number of audio samples required for the fading process remain in the associated buffer. The new audio stream is not faded in until a selected number of audio samples have been stored I the associated buffer. The selected number of samples is typically smaller than the number of samples that is desirably stored in the associated buffer during steady state operation. An interpolation operation is used to allow the number of new audio samples in the associated buffer to build up to the desired number.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.