[Vorbis-dev] Vorbis bistream definition / separation from ogg

[Nico Sabbi]

Hi,
I have some questions:

1) in the sources of the encoder_example (and of course in oggenc.c, 
too) I see a lot of dependance
on ogg. I want to get totally rid of ogg and use the vorbis bitstream 
alone.
 From this reason stems the second question:

2) is there a definition of the vorbis bitstream somewhere? I don't need 
to know every single
detail, just the informations necessary to isolate frame boundaries, 
frame size, and frame duration in ms.

3) does vorbis always use a variable number of samples per frame? If so, 
is there a way to know
from every frame how many samples are used? Is there any disadvantage at 
using a constant
number of samples per frame (as in mpeg audio, aac, musepack and so on) ?

Thanks,

    Nico