[MPlayer-users] speed difference

[Corey Hickey]

anton wrote:
> [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]
> Any idea why:
> 
> mencoder -oac copy -o /dev/null -ovc lavc -lavcopts 
> vcodec=mpeg4:vbitrate=1794:mbd=2:vpass=1 -vf 
> crop=716:428:2:74,scale=640:272 tower
> mencoder -oac copy -o tower1.avi -ovc lavc -lavcopts 
> vcodec=mpeg4:vbitrate=1794:mbd=2:vpass=2 -vf 
> crop=716:428:2:74,scale=640:272 tower
> 
> gave me 50 fps and:
> 
> mencoder -oac copy -o /dev/null -ovc lavc -lavcopts 
> vcodec=mpeg4:vbitrate=1757:mbd=2:vpass=1 -vf 
> crop=716:428:2:74,scale=640:272 -endpos 6236 tower2
> mencoder -oac copy -o tower2.avi -ovc lavc -lavcopts 
> vcodec=mpeg4:vbitrate=1757:mbd=2:vpass=2 -vf 
> crop=716:428:2:74,scale=640:272 -endpos 6236 tower2
> 
> is giving me 40 fps? Given that this is the only cpu intensive thing 
> I've been doing? (they are discs 1 & 2 of LOTR-2 Towers extended). Audio 
> was done exactly the same way...
> Cheers
> Anton
> 

The bitrates you posted are different: 1794 on disk1, 1757 on disk2.
I don't know why that would make so much of a difference, but that will
alter framerates at least some.

Also, it might very well be that the second disk has more rapid
motion/changes, which are more difficult to encode quickly.

Besides that, are "tower" and "tower2" on the same hard drive? Hard
disk performance is known to decline as data is written farther from
the edge. Also, since DVD dumps are very large files, the second one
might be more fragmented because there was less continuous free space
to jam it into.

...that's all I can come up with off the top of my head...

-Corey