[mythtv] Lame bitrate?

[Torbjörn Jansson]

I have a question about lame and mp3.

The directshow filtes that im working on need to do some calculations based
on the bitrate. It looks like all audio encoded with mp3 in mythtv uses
128Kbit. Is it safe to asume that its always 128Kbit? Or is there any way of
detecting it by looking at the file header?
I have looked at the source for mythtv and i didn't find any specific
bitrate being used only that it uses CBR (i think).

The struct i need it in (MPEGLAYER3WAVEFORMAT) is very badly documented and
the closest to documentation i found was in lame and the acm/dshow filter
source.

Using MPEGLAYER3WAVEFORMAT seems to have fixed the problem with the avi mux
filter not accepting audio.