[theora] Number of frames

[Morten Winkler Jørgensen]

Hi Michael

> That's approximately right. Because Ogg is designed as a streaming
> format, it doesn't contain information about the length of the stream
> in the header.
In that case it makes sense.

> So basically, you need to find the final frame in the file, and get
> the frame number of that. You'll also probably want to read the start
> of the file, to check what frame number it starts from (it might be
> non-zero if the file has been captured from a stream, or edited out of
> a larger file, etc.)
Good point. I'll pay attention to that. 

Thank you,
   Morten