FFmpeg audio channels

[khaled22]

Hi

how can i re encode the audio stream from a video from 6ch to 2ch?

[davexnet]

Read through this thread (post #28 specifically):
https://forum.videohelp.com/threads/369941-Quiet-sound-on-youtube

[pandy]

Hi

how can i re encode the audio stream from a video from 6ch to 2ch?

You need perform operation called 'downmixing'

https://trac.ffmpeg.org/wiki/AudioChannelManipulation#a5.1stereo

or

custom downmixing

-af "pan=stereo|FL < FL+1.414FC+0.5BL+0.5SL+0.25LFE|FR < FR+1.414FC+0.5BR+0.5SR+0.25LFE"

[ProWo]

Hi

how can i re encode the audio stream from a video from 6ch to 2ch?

Use clever Ffmpeg-GUI.
Load your video, click main, click encode audiostream, select your 6ch audio stream, click go to the encoder, select the codec and the 5.1 to 2 channels, click the D-mix options button and select one of 4 formulas, click ok and click encode.
If finished, click multiplex, select the new created 2ch audiostream (in green), the videostream and other streams you want and click multiplex.
Done.

[khaled22]

thank you all for your replies..ill check them out..managed to do it also by using "pan=stereo|c0=FL|c1=FR"

[pandy]

thank you all for your replies..ill check them out..managed to do it also by using "pan=stereo|c0=FL|c1=FR"

This means you are loosing audio from other channels - for example if something was only in FC (like dialogue) then it will be not present in your stereo - proper downmixing trying to preserve audio from all channels in stereo.