| 摘要 |
In order to transmit an inter-frame coded video signal, such as an MPEG-coded video signal, over a packet-based network such as the Internet, the video signal associated with at least one video frame, is split into a high priority partition and a low priority partition. A systematic forward error erasure/correction (FEC) code, such as a Reed Solomon (n,k) code, is then applied to bytes in the high priority partition. The forward error/erasure corrected high priority partition bytes and the low priority partition bytes are then combined into n packets for transmission over the packet network to a receiver/decoder. Each of the n transmitted packets contains a combination of both high priority partition data bytes and low priority partition information bytes. In k of those packets the high priority partition data bytes are all high priority partition information bytes and in n-k of those packets all the high priority partition data byte are parity bytes produced by the FEC coding. More specifically, for each high priority partition byte position within the n packets, the forward error/erasure correction code is applied using one high priority partition information byte from the same byte position in each of those k packets to determine n-k parity bytes, which are arranged, one byte per packet, in then- k packets containing high priority partition parity bytes. If up to n-k packets are lost in transmission over the packet network to the receiver, then the high priority partition bytes in such lost packets can be recovered to applying FEC decoding to the high partition bytes in the received packets. The most visually significant information is thus protected against packet loss over the network.
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