Theora är en fri videocodec som trivs bra i en Ogg bitstream.
- http://theora.org/
- http://en.wikipedia.org/wiki/Theora
- svn co http://svn.xiph.org/branches/theora-mmx/
Tyvärr står det inte hur codecen funkar på dessa sidor!
Titta på Theora-videos
Lista över videos enkodade med Theora
Patentproblem
Inga kända patentproblem hävdar utvecklarna, men det finns de som hävdar att det inte är så enkelt:
»The Xiph people go around promoting theora is if it had some major ideological advantage over other codecs (particularly mpeg4). They claim it is non-patent-encumbered and thus 'more free'. This is a blatent lie. Virtually every single patented algorithm used in mpeg* codecs is also used in theora. Now, by prior art and obviousness, ALL of these patents are blatently invalid and should be ignored. But the point is that as far as patents go, theora is on equal ground with all other modern codecs: either all of them infringe, or none of them do. This issue has been discussed numerous times on the mplayer and ffmpeg lists, and all the codec experts seem to agree.«
Källa: D Richard Felker III på e-postlistan MEncoder-users 2005–03–05
»Having read quite a few patents I tend to agree with Richard: Software patents are very broad and even if I have not read the source code of Theora I would be surprised if it did not infringe several patents.
However, I believe the argument that On2 has not been sued for infringing the MPEG-patents is a very strong argument. This indicates that you will not be sued if you use Theora which basically is what people are interested in knowing.«
Källa: Ole Tange på e-postlistan MEncoder-users 2005–03–29