[theora] oggplay vorbis stream and theora seeking

[fungos]

I'm very new to video decoding and I'm trying to implement a clean
theora player for games and I liked oggplay, it is clean, plain and
simple.

1. I already have a vorbis decoding implementation and I would like to
know if there is a way to get the vorbis stream and use it directly in
(a custom) vorbis decoding when using oggplay?
2. When trying to seek using oggplay I get video artifacts, reading
theora samples there is comment marked with HACK that says something
about correcting keyframes so some artifacts will not appear. How can
I achieve the same but using oggplay?

Thank you,
Danny