Table of Contents
Advertisement
APPENDIX G: AVAILABLE FEC
FEC (Forward Error Correction) is a mechanism which consists in sending redundant information (redundant
frames) to the decoder so that it can compensate packet transmission errors on unreliable networks.
An FEC can be selected when defining the parameters of the stream to be generated and/or to be received.
FEC requiring no additional stream
Redundant frames are sent in the same stream as the IP audio stream.
The FEC to be selected is "+50% bandwidth, recovery 2, 1 stream (audio)".
Its characteristics are: +50% bandwidth, additional delay of 2 frames, recovers 1 lost packet at 100%, recovers 2
consecutive lost packets at 75%.
FEC requiring an additional stream
Redundant frames are sent as a second stream of data. The used port is by default: port of the IP audio stream + 2.
Selectable FECs are:
●
+100% bandwidth, recovery 3, 2 streams (audio + FEC)
+100% bandwidth, additional delay of 1 frame, recovers 2 consecutive lost packet at 100%, recovers 3
consecutive lost packet at 75%
●
+100% bandwidth, recovery 4, 2 streams (audio + FEC)
+100% bandwidth, additional delay of 4 frames, recovers 3 lost packet at 100%, recovers 4 consecutive
lost packet at 80%
●
+50% bandwidth, recovery 1/2, 2 streams (audio + FEC)
+50% bandwidth, additional delay of 1 frame, recovers 1 lost packet over 2 consecutive packets.
●
+33% bandwidth, recovery 1/3, 2 streams (audio + FEC)
+33% bandwidth, additional delay of 3 frames, recovers 1 lost packet over 3 consecutive packets.
●
+25% bandwidth, recovery 1/4, 2 streams (audio + FEC)
+25% bandwidth, additional delay of 4 frames, recovers 1 lost packet over 4 consecutive packets.
●
+20% bandwidth, recovery 1/5, 2 streams (audio + FEC)
+20% bandwidth, additional delay of 5 frames, recovers 1 lost packet over 5 consecutive packets.
●
+10% bandwidth, recovery 1/10, 2 streams (audio + FEC) – From firmware 2.31
+10% bandwidth, additional delay of 10 frames, recovers 1 lost packet over 10 consecutive packets.
I QOYA *CALL - IQOYA *CALL/LE
User Manual v0.99
76 / 77
Advertisement
Table of Contents
