| 摘要 |
FIELD: physics, computer engineering.SUBSTANCE: invention relates to data formats of multimedia applications which use hierarchical data layers. The method for encoding an audio or video signal has a base layer bit stream and an enhancement layer bit stream relating to the base layer bit stream. The base layer data and the enhancement layer data are structured into packets and packets of the base layer bit stream have corresponding packets of the enhancement layer bit stream. The method involves calculating a checksum of a packet of the base layer bit stream and a corresponding packet of the enhancement layer bit stream, as well as entropy encoding the packet of the base layer bit stream to obtain an entropy encoded, byte-aligned base layer packet starting with a synchronised word.EFFECT: enabling detection of synchronisation loss between enhancement layer data and base layer data during decoding, while the amount of synchronising information and check information in the enhancement layer data stream is kept low.13 cl, 7 dwg |
