What does "Guessed Channel Layout for Input Stream" mean? And is it bad?

[Guernsey]

I was using batch resizes using an FFMPEG command that I learned about from another forum but as FFMPEG was encoding for me, I get this line "Guessed Channel Layout for Input Stream #0.1: stereo" during the encoding process. I think I did everything everything as I input the command as instructed by the forum but I get that line and I wonder what it all means? Is it simply a function that allows FFMPEG to come up with an educated guess on what the sound input is like? Or is it an error?

[jagabo]

It means you didn't specify the audio channel layout (left, right, center, rear left rear, rear right, sub...). So ffmpeg guessed. If it guessed right, that's good. If it guessed wrong, that's bad.

[Guernsey]

What would be a good command to tell FFMPEG that is actually stereo, mono or otherwise so that it doesn't have to guess?

[aedipuss]

just a guess but was the original audio dolby atmos? ffmpeg just doesn't have a clue how to handle it and it ends up as screwed up stereo. use something else to convert/downsize to standard ac-3 5.1 like vidcoder/handbrake.

[Guernsey]

Looks like I will have to do that as FFMPEG native encoder messes up my audio unless I put in 128k or 320k.