[MEncoder-users] Mencoder + xvid giving less quality than VirtualDub + Xvid

[Nico Sabbi]

Manu J wrote:

>Hi,
>Recently i encoded a DVD to Xvid using both Mencoder
>and VirtualDub and i found that VirtualDub gave a
>better quality for the same filesize.
>
>Here is the command i used for mencoder.
>cat *.VOB | mencoder -vf
>crop=720:378:0:52,scale=640:272,pp=lb -ovc xvid
>-xvidencopts
>bitrate=900:me_quality=6:quant_type=mpeg:gmc:trellis:chroma_opt:chroma_me:hq_ac:vhq=3:autoaspect:max_bframes=3:qpel:pass=1
> -oac mp3lame -lameopts q=3:vol=7 -  -ofps 23.96 -o
>/dev/null
>
>cat *.VOB | mencoder -vf
>crop=720:378:0:52,scale=640:272,pp=lb -ovc xvid
>-xvidencopts
>bitrate=900:me_quality=6:quant_type=mpeg:gmc:trellis:chroma_opt:chroma_me:hq_ac:vhq=3:autoaspect:max_bframes=3:qpel:pass=2
> -oac mp3lame -lameopts q=3:vol=7 - -ofps 23.96 -o
>dch.avi
>
>Now i tried many variations and there was never a
>significant change and atlast i got tired and i went
>with these options :-).Mencoder took much longer time
>to encode than virtualdub possibly because i enabled
>so many xvid options like gmc,qpel.
>
>I forgot the settings for virtualdub but i just
>followed the doom9.org guide and used the same
>seetings.
>
>Now some questions
>1)Is there a way to speed mencoder up without losing
>quality ? I have only linux and i don't want to
>trouble my friend often
>
>  
>

vhq=3 is always extremely slow on both windows and linux

>2)Am i doing something wrong here especially with
>respect to scale and crop? Which should be done first?
>  
>

they are in the right order, but are you sure you are using a linear blend
deinterlacer and a bicubic scaler in vdub (as in the cli above)?

>3)Is there any xvid setting that i missed which would
>have made a difference in quality? I tried enabling
>4mv but mencoder said it's not a valid option though
>TFM says otherwise !
>
>
>  
>

me_quality=6 implies 4mv. BTW are you sure you want trellis and 3 B frames?
-ofps 23.96 is wrong: 24000/1001 (=23.976) is the right value

>System and siftware details
>
>Slackware linux 10
>AMD Athlon 1700
>MPlayer 1.0pre5try2-3.4.2
>Wine 20041019
>Xvid 1.0.2
>
>Regards
>Manu
>
>
>
>  
>