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poor quality decode on sequential dropped frames.

Open weepy opened this issue 4 years ago • 4 comments

The audio quality of multiple (small) dropped frames is considerably worse than that of a single frame of similar size. Is there a reason for this or a way to work around it?

weepy avatar Jan 25 '21 13:01 weepy

E.g. If I decode 4 x 120 dropped frames - it's worse than 1 x 480 frame .

Is there a reason for this ?

weepy avatar Jan 26 '21 09:01 weepy

I was expecting some worse PLC but this looks like a bug to me (removing people)

Repro: Reference (no loss) Encode decode 24% packet loss single packet 10ms frames 48kHz audio mode 256000 bitrate lost = (((count + 1) % 4) == 0) ? 1 : 0; opus_demo audio 48000 1 256000 -framesize 10 five.pcm out.pcm Encode decode 24% packet loss 4 packet burst loss 2.5ms frames 48kHz audio mode 256000 bitrate lost = (((count + 4) % 16) < 4) ? 1 : 0; opus_demo audio 48000 1 256000 -framesize 2.5 five.pcm out.pcm

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xnorpx avatar Jan 28 '21 07:01 xnorpx

Should you also set OPUS_SET_PACKET_LOSS_PERC ?

weepy avatar Jan 28 '21 11:01 weepy

Right, that's true the setting control packet dependency so it makes sense. Can you share samples what you hear and the exact settings of the quality issue you experience?

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xnorpx avatar Jan 28 '21 19:01 xnorpx