[vorbis-dev] Just looking for some information...

[Monty]

> In vorbis_info, is int rate; the sampling rate of the data being output or
> the bitrate of the encoded stream?  If it is the sampling rate, is there
> some way to get the bitrate? (or vice versa)

That's the sampling rate.  I've resisted putting in a 'bitrate' field because
it would be an artificial quantity.  Vorbis is variable bitrate by nature and,
like MPEG, you can write an encoder that adheres to certain bitrates, but as
soon as encoders begin navigating the gray waters inbetween, a bitrate field
becomes misleading at best.

> The only other thing I'm in need of is some way to determine (in seconds)
> the length of a stream...

If it's a true stream, you can't know; you're potentially decoding while
encoding may still be taking place.  When you *do* have access to a whole
stream, the PCM position that a page represents in the original stream is part
of the page header (frameno).  This is covered in the framing docs (I *think*
that one is up on the web site) but will probably be confusing without example
code once chaining is mixed in.  I'll write up something for this too (and get
some example bitstreams to test with), but I'm not going to be able to do that
today.  Tomorrow looks good tho...

BTW, the commit I was hoping to do yesterday didn't happen.  I've bugs left to 
hunt first.  I'll let you all know when it does.

Monty

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