VORBIS OGG support is provided by LIBVORBIS and LIBOGG 

Decoder	VORBIS OGG
File extension	ogg
Description	VORBIS encoding + OGG bitstream format. Use only first logical bitstream. See Remarks.
Supported by	LIBVORBIS library and LIBOGG library.
Web	http://www.vorbis.com/
Email	feedback@vorbis.com
Copyright ©	2002-2004 Xiph.org Foundation VORBIS BSD-STYLE SOURCE License
Info tags	Supported by VORBIS COMMENT.
Reverse playing	Supported.
Accurate length	Supported.
Accurate seek	Supported.
BPM detection	Supported.
Gapless playing	Supported.
Dynamic streams	Supported.
Format autodetection	Supported by analyzing file extension and detecting VORBIS COMMENT tag at stream beginning.
Audio autodetection	Supported.
Recording/Encoder	Supported by LIBVORBIS library and LIBOGG library.
Supported channels	1 channel (mono), 2 channels (stereo)

This decoder will only decode first logical bitstream from ogg stream. So, if ogg stream contains multiple logical bitstreams, only first logical bitstream will be decoded. You can't access other logical bitstreams. 

Supported formats