Patent ID: 8315312
Filing Date: 2012-11-20
Classification: H04L,H04N

Abstract:
1. An IP stream communicating system having a receiving apparatus which, when a reception IP (Internet Protocol) stream is inputted, performs at a reception processing timing at least FEC (Forward Error Correction) decoding processing that takes place immediately after reception of the reception IP stream, the IP stream receiving apparatus comprising: a PCR extracting circuit which extracts a PCR (Program Clock Reference) that has been periodically added into the reception IP stream; an RTP (Real-time Transport Protocol) information extracting circuit which extracts RTP information from an RTP header in the reception IP stream; and a sync calculating circuit which generates block sync of the FEC decoding processing based on PCR information extracted by the PCR extracting circuit and the RTP information extracted by the RTP information extracting circuit, wherein the RTP information includes at least a sequence number of an RTP packet containing the PCR extracted by the PCR extracting circuit and a position in a payload portion of the RTP packet containing the extracted PCR, and wherein the sync calculating circuit calculates a difference between an nth PCR and an (n+1)th PCR (where n is a positive integer), a number of TS packets between the nth PCR and the (n+1)th PCR, and a single RTP packet period, and calculates a single FEC block period based on the calculated results.