How can I verify if FEC is working? I am not hearing any changes with fec enabled vs disabled with 30% packet loss

[sumanth-murali-skydio]

I am running an opus encode decode pipelein. This takes in a raw pcm at 16 KHz mono and encodes with FEC enabled at 16 kbps and complexity = 10. The frame size is 40 ms and I am simulating packet loss by not dropping the encoded packets. The decoder then decodes with decode_fec = true if it sees a packet missing (using sequence numbers) and decodes the packet again with decode_fec = false. I dont hear any difference when I enable FEC or if I disable FEC. Are there specific settings for the encoder that allow the FEC to work??

[jmvalin]

I suggest you test with opus_demo. Also, make sure you're setting the -loss to something non-zero and using a high enough bitrate for FEC to get used.

[sumanth-murali-skydio]

What is the minimum bit rate needed??