[theora] Lossless Video Codec

Ralph Giles giles at thaumas.net
Sat Jul 10 09:15:28 PDT 2010


On 10 July 2010 02:25, Lino Mastrodomenico <l.mastrodomenico at gmail.com> wrote:

> BTW, I'm surprised by how many of these open source (some with patent
> problems) lossless codecs are intra-only: FFV1, MPNG, lossless MJPEG.
> I think only Dirac offers inter frames for lossless compression.
>
> Why is that? The gain from inter frames is much smaller for lossless
> than lossy codecs?

I think it has more to do with editing requirements and simplicity.
Inter frame codecs are much more expensive to use in an editing
context, where one needs to scrub and cut between arbitrary frames.
Inter compression is really only useful for archiving, and I suspect
the additional space saving isn't considered worthwhile just for those
applications. See also the common film practice of just using a
directory full of image files.

MNG does have an inter frame mode, but I'm not aware of a
video-optimized encoder for it.

 -r


More information about the theora mailing list