[MEncoder-users] x264 encoding slower after updating libx264

[Reimar Döffinger]

On Sat, Nov 14, 2009 at 03:52:52PM +0100, Christian Ebert wrote:
> * Loren Merritt on Saturday, November 14, 2009 at 13:49:43 +0000
> > On Sat, 14 Nov 2009, Christian Ebert wrote:
> >> weightp is set to 2 by default:
> >> 
> >> $ x264 --fullhelp | grep -A 2 weightp
> >>    --weightp               Weighted prediction for P-frames [2]
> >>                            - 0: Disabled
> >>                            - 1: Blind offset
> >> 
> >> This adds 2 reference frames, so for converted files to play on
> >> iPod one has to set weightp=0. I found out the hard way ;-)
> > 
> > You may be right that iPod doesn't support weightp (I don't keep
> > track of hardware decoders). But it's not because of the number of
> > refs. Weightp adds 2 entries to the ref list, but they aren't extra
> > frames, so they don't count against the DPB limit.
> 
> According to Dark Shikari in this thread
> 
> http://forum.doom9.org/showthread.php?p=1342762
> 
> weightp 2 adds 2 reference frames.

That's not quite how he meant it. Those are about in the same way
reference frames as swap space is RAM.