Audio clocking in video applications
US8378867B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 19, 2009 |
| Grant date | Feb 19, 2013 |
| Priority date | — |
| Expiry date | Nov 3, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/2562
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of operating an electronic video device such as a DVD player, wherein video clock signals and audio clock signals are derived from a system clock signal using two phase-lock loops, and these video and audio clock signals are used to process encoded video data and encoded audio data, but digital-to-analog conversion of the audio data stream is controlled by the system clock signal rather than the audio clock signals. By using the system clock signal to control the audio digital-to-analog converter (DAC), the DAC avoids the poor performance issues that can arise from jitter introduced into the audio clock signals by the PLL. The system clock signal may be divided by an integer to generate the sampling clock for the audio DAC. In the illustrative embodiment, the system clock signal has a rate which is not an integer multiple of the sample rate of the audio data stream.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.