[MEncoder-users] losing 5.1 audio on -oac copy transcode

[R.L. Horn]

On Tue, 23 Sep 2008, Wes Morgan wrote:

> If I use the "-channels 6" option when ripping, "file" reports that the 
> resulting AVI has the proper number of channels.

I see this as well.  It looks as though mencoder, directly or indirectly, 
is using a52_frame() to obtain stream information where it should be using 
a52_syncinfo().  The former returns information about a decoded frame 
_after_ mixing to the requested number of channels.  The latter, objective 
information about a frame (at least according to the a52dec 
documentation).

The end result is spurious information being placed in the avi file (auds 
chunk?).  The audio stream itself is unmodified.