I have also had the issue of struggling to render 5.1 audio from Cinelerra and
have it come out in the correct channels. I'm sorry to say that I don't have a
solution (being decidedly an end user and not particularly confident in
understanding what's going wrong), so if anyone else has an actual solution
rather than this rather convoluted workaround, please let me know. However, I
do have a workaround.
Basically I render each audio stream separately as a mono channel .wav file (to
do this, make sure you temporarily change your project settings so that there
is only a single audio track, then ensure only the appropriate audio channel is
set to play before rendering the audio).
I then use sox to create a mutlichannel .wav file. Use the following command
(with appropriate filename substitutions) for order for this to occur correctly
(the order you put the audio tracks in matters - it needs to be left, right,
centre, LFE, surround left, surround right):
sox -M left.wav right.wav centre.wav lowfrequencyevents.wav surroundleft.wav
surroundright.wav 51wavfile.wav
You now have a 5.1 .wav file, and my personal preference is to then convert
this to a 5.1 .ac3 file using aften. I find the following command does the
job:
aften -b 448 -dsur 2 -acmod 7 -lfe 1 51wavfile.wav finalaudio.ac3
I can then mux the .ac3 with a rendered .m2v file in mplex or drop straight
into a program like DVDStyler as the audio track.
As I said, it's a very long workaround and if anyone has a solution that is
faster, I would also be grateful to hear it, but without another solution, this
does at least work. :)
