Vorbis - Aug 2008 - Tremor + upstream Ogg library

Hi vorbis experts!

I'd like ot write application under Symbian that use theora as video
codec & tremor as an audio one. I played at first with libogg &
theora on PC, then successfully ported them both. Next I decided
to port Tremor but I found that it use its own files from Ogg library.
The API is almost identical, so I tried to bind the Tremor with upstream
Ogg library (it actually consist of bitwise.c & framing.c), with a few
changes. I had no luck, the decoder_example.c from Vorbis packege
is built successfully, but didn't decode something properly, I got nothing
but noise (being linked with native vorbis lib it decodes perfectly).

I started to walk inside Ogg sources as well as its Tremor version, and found
that they use quite different version of data structures, oggpack_buffer for
instance. For another example, oggpack_readinit uses argument of `struct
ogg_reference' type, which lacks in upstream library at all. So I guess that
the functions despite from their identical name do not do identical things.

So the problem is: I need to use in my application the code from three
libraries: Ogg, Theora and Tremor. Theora relies on upstream Ogg, Tremor
is based on its own Ogg, and that Ogg's are seem to be imcompatible.

Finally, 2 question:

1) did anybody try to adjust Tremor for binding it with upstream Ogg library?
2) *why* it once was decided to leave Tremor with frozen Ogg code?

Much tthanks in advance.

Greetings,
Timur

Did you mean to send this twice?

Tremor uses a development copy of a revised libogg. It's got a smaller
memory footprint and fewer memcpy()s, which was the main motivation.
Tremor was targeted at hardware audio players, so building in the Ogg
parser wasn't an issue. The apis look similar, but the memory
discipline is completely different so you can't just link to the
normal libogg. Changing the code shouldn't be too hard though.

The revised libogg (see http://svn.xiph.org/trunk/ogg2/) was never
completed. Some of the alpha libtheora releases can build against it,
but the faster beta decoder can't.

So the easiest thing is to build a bridge demuxer that feeds pages to
either standard libogg->libtheora chain or to Tremor's internal
libogg2. The next less easy thing is to port Tremor or libtheora to
the other's ogg parser and bit(un)packer. Either way you'll have to do
some work, unfortunately. Does gstreamer have a symbian port? That
code already does the first option.

I don't know how the CSIRO symbian port handled this. Perhaps someone
who was involved can comment.

 -r