Two weeks a go I was in a meeting – the issue was about CC error , since no one really knew what is "cc error" , I was asked to figure out what is CC error , well … this was a task with no real information in hand , actually I knew its something to do with video multicasting , so I was looking for some clue about cc error in UDP/RTP header , but ,,, found basically nothing , the problem was I did not know what 'cc' stands for . Then I assumed that may be CC error is related to the MPEG-2 frame - ..ha ha … yha I was correct , cc = 'continuity counter' …. so the cc error is "continuity counter error" , this is used for keeping a track of the sequence of the MPEG-2 frames , and if you are seeing "cc error" at the clients end when you are using some video stream analyzer like "IQmedia" , the error can be mainly due to ,
1) one packet repeat more than twice
2) packets out of sequence
3) packet loss
each UDP packet of 1316 bytes carry 7 MPEG-2 frames of 188bytes each – each MPEG-2 frames has 4 byte header and the last byte is for continuity counter .
ETH | IP | UDP | FR-1 | FR-2 | FR-3 | FR-4 | FR-5 | FR-6 | FR-7 | Eth… |
Frame – 1 (FR-1)
SYN(8) | TEI(1) | PUSI(1) | TP(1) | PID(13) | TSC(2) | AF(2) | CC (4) | Video |
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