[FFmpeg-user] Fwd: "Guessed Channel Layout for Input Stream" - how to assign channels? (FL+FR+FC+LFE+BL+BR)

Carl Eugen Hoyos cehoyos at ag.or.at
Tue Apr 2 13:26:13 CEST 2013

Steve C <natgeo.operations <at> gmail.com> writes:

> do you think there is some way to apply the -channel_layout 
> twice, so to cover all 16 tracks?

I don't understand this question;-(
Did you already test the option?
If not, that would explain your question and 
why I cannot answer it.
(You have to specify the option 16 - or at least 
14 - times.)

> if no, is there some way to prevent FFMPEG from guessing 
> the channel layout and making all channels 
> "Channel positions : Front: C"

The fact that FFmpeg tries hard to guess a channel_layout 
for every audio input is a regression; it couldn't be 
fixed until very recently because of some (very broken) 
changes to FFmpeg, I believe this has been fixed now (ie 
audio without channel layouts should be supported again).

I am not convinced anybody is working on reverting 
"always guess a channel layout", probably because 
developers do not see this as a bug.

Carl Eugen

More information about the ffmpeg-user mailing list