System and method for updating a system time constant (STC) counter following a discontinuity in an MPEG-2 transport data stream
US5818539A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 1996 |
| Grant date | Oct 6, 1998 |
| Priority date | — |
| Expiry date | Mar 29, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/434
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A transport decoder 110, for receiving and processing a transport data stream using MPEG-2 formats, includes connections to a physical layer channel interface (channel interface) 112, a buffer memory 114, a host microprocessor 116, audio and video decoders 118/120, and clock signal circuitry 122. Upon receipt of a discontinuity indicator, the transport packet headers are parsed and transport packet payloads are stored in memory. Subsequently, upon receipt of a next program counter reference (PCR) value, a counter is loaded with the received program counter reference value. Next, the data stored in memory is searched for a time stamp and, when one is found, the time stamp is retrieved. Finally, a timer interrupt is set for a point in time approximately one frame time before the time stamp value, and, when the timer interrupt occurs, the program counter reference value is sent to the decoders, thereby providing sufficient time for the decoders to process data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.