[FFmpeg-devel] [PATCH] FFV1 2pass

Michael Niedermayer michaelni
Sun Oct 24 13:06:47 CEST 2010


On Sun, Oct 24, 2010 at 09:52:37AM +0000, Loren Merritt wrote:
> On Sat, 23 Oct 2010, Michael Niedermayer wrote:
>
>> The patches below add a 2pass mode to ffv1 that optimally sorts the range
>> coder states. The compression gain is for my test quite small but more things
>> can be added in the future to be finetuned in 2 passes ...
>> Also ive not been able to meassure speedloss here for the added code.
>
> Why is the default ever nonmonotonic? I could understand optimizing the  
> transition table in ways that don't preserve isomorphism (e.g. adjust  
> learning rate), but not just a reorder.

note, i also have code in a local branch that optimizes the transitions
in the table iteratively, this is what created the default table. But
its really slow (speaking of minute per frame instead of frames per second)
i was planing to clean this up and post it and maybe commit depending on
feedback (iam not sure how usefull it would be to end users ...)

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Good people do not need laws to tell them to act responsibly, while bad
people will find a way around the laws. -- Plato
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 198 bytes
Desc: Digital signature
URL: <http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/attachments/20101024/a7e3722a/attachment.pgp>



More information about the ffmpeg-devel mailing list