| 摘要 |
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 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 a 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 dependent on 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. <IMAGE> |
