Signal processor
US6983015B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 24, 2000 |
| Grant date | Jan 3, 2006 |
| Priority date | — |
| Expiry date | Aug 28, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/90
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Decoders A and B decode MPEG-2 bitstreams A and B. A switch (S1) switches from decoded stream A to decoded stream B to achieve a splice. The resulting bitstream is re-encoded in an encoder 4. A new transitional GOP is defined beginning at the splice. The new GOP is defined by picture type decision rules which may have the effect of changing the GOP compared to the GOPs of streams A and B. The new GOP provides an initial prediction of the position in stream B where the occupancy value of stream C should coincide with that of B. A target for the new number of bits in the new GOP is calculated as the sum of the normal allocation of bits for the new GOP plus the difference between the occupancy value of stream C at the splice and a prediction of the occupancy of stream B at the predicted position. The occupancy value of stream C is controlled in accordance with the target so that it tends towards the occupancy value of stream B at the predicted position.The target is updated regularly throughout the GOP on I and P frames. After the first update at the beginning of the transitional GOP, the target changes at the updates nominally by an amount VBV—diff which is the difference between occ…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.