[theora] Loseless Video Codec

Philip Jägenstedt philip at foolip.org
Tue Jan 5 11:35:34 PST 2010

On Tue, Jan 5, 2010 at 01:29, Benjamin M. Schwartz
<bmschwar at fas.harvard.edu> wrote:
> Daniel Hendrycks wrote:
>> Is there a Lossless video codec developed by Xiph? Is one in the works? There is
>> already a losseless audio codec available by Xiph: FLAC.
> You can do lossless video in Ogg using Ogg Dirac.  Dirac has a lossless
> mode, and the Ogg embedding of Dirac is well supported.  This is much like
> the situation with FLAC.

Incidentally I've been experimenting with lossless Dirac the past few
days, using GStreamer schroenc rate-control=3. The idea was to convert
some lossless mjpeg to something that could be muxed with FLAC for a
master copy of kinds. Unfortunately, it turned out that resulting
dirac video was bigger than the original mjpeg by perhaps 10% (didn't
check carefully).

Perhaps there are some extra options I should have used, otherwise it
seems that lossless Dirac isn't (size-wise) the best option for
lossless video just yet.

Philip Jägenstedt

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