[MEncoder-users] Wrongly guessed bitrates for 2x700 MB CDs

[Niki Kovacs]

Hi,

I just successfully encoded a DVD using this set of commands:

$ mencoder -dvd-device HIGH_FIDELITY/ dvd://1 -aid 128 -sid 2 -oac 
mp3lame -lameopts mode=2:cbr:br=96:vol=0 -ovc frameno -o frameno.avi

... which gave:

Writing index...
Writing header...
ODML: Aspect information not (yet?) available or unspecified, not 
writing vprp header.
Recommended video bitrate for 650MB CD: 723
Recommended video bitrate for 700MB CD: 787
Recommended video bitrate for 800MB CD: 916
Recommended video bitrate for 2 x 650MB CD: 1557
Recommended video bitrate for 2 x 700MB CD: 1685
Recommended video bitrate for 2 x 800MB CD: 1942


I wanted to have the resulting .avi to fit on two 700 MB CDs, so I chose 
1685 for bitrate:

Video pass 1:

$ mencoder -dvd-device HIGH_FIDELITY/ dvd://1 -aid 128 -sid 2 -vf 
crop=688:528:16:20 -oac copy -o /dev/null -ovc lavc -lavcopts 
vcodec=mpeg4:vbitrate=1685:vhq:autoaspect:vpass=1

... and then:

$ mencoder -dvd-device HIGH_FIDELITY/ dvd://1 -aid 128 -sid 2 -vf 
crop=688:528:16:20 -oac copy -o High_Fidelity.avi -ovc lavc -lavcopts 
vcodec=mpeg4:vbitrate=1685:vhq:autoaspect:vpass=2

The resulting .avi is of very satisfying quality... only it is almost 
1.7 MB big... which is much too large to fit on two CDs.

Q: how can I guess correct bitrates?

Regards,

Niki Kovacs (France)