Single Pass Xvid Target Bitrate problem

[clubrulz]

Here is my issue,

I am trying to reduce the size of my videos so I can burn three or four to one DVD. I am encoding them using an Avisynth script through Virtualdub and I set the Xvid Target bitrate to 1050 kbps (512x384) hoping to get the file size down to around a gig per 1.75 hr movie. After encoding the files are still over two gigs and when I check the Gspot stats it has been encoded at 2000+ kbps.

Does anyone have any thoughts as to why this may be happening. I have also tried 2pass encoding and get the same result.

Thanks

[D734]

I'd recommend doing 2 pass as that will yield more quality (not like xvid takes that long to encode anyway)

one guess would be that the max i/p/b quantizers are set to such a low value that it forces it to use a higher bitrate.
or maybe a combination of that and low settings.

a decent xvid setup guide is http://www.divx-digest.com/articles/xvid_setup_page1.html (although use unrestricted profile not AS@L5)
note: vhq4bframe on and vhq 4 vs vhq4bframe off and vhq 1 will give a little better quality but not crucial or anything.

EDIT: i just ran an encode with noob (i mean auto) GK because i remember it messing with the quants before (note i NEVER have used this for an actual encode) and it set the max quants to 4... thats gonna cause files to be a lot bigger then expected