Xvid file size too small [converting from DV]

[Jumbie]

Xvid 1.1 (although same problem with 1.03)
VirtualDub 1.5
DV .avi (31 mins 4 seconds long)
Lam MP3 codec at 224 kbps

Using the following Vdub filters in this order: [full processing mode]

- Deinterlace: discard field 1 (NTSC file format and plays back fine on my PC monitor without any jerkiness as far as I am concerned)
- Lanczos3 resize to 320x240 (from 720x480)
- levels (increase gamma by 1.3)
- brightness increase by 7%
- Smart smoother HiQuality (2.11) [Klaus Post] - based on filter by Donald Graft]

Xvid settings are

- 2 pass VBR
- target size on second pass = 666167
- Profile AS@L5
- Quantization H.263
- Quarter Pixel
- Packed Bitstream
- B-VOPs (max = 2, ratio = 1.5, offset = 1)

Advanced:

- Motion Search Precision 6 Ultra High
- VHQ Mode 1 [Mode Decision]
- use VHQ fro bframes too
- use chroma motion
- turbo

Quantization:

2 31 2 31 2 31
- use trellis quantization

***

Video ended up being 377 MB instead of ~ 700

I'm assuming that this is because of the resize, but is there any way for me to compensate for it when setting target size? Or do I just have to guess and make it approximately double what I have now?

Thanks.

[Jumbie]

Been doing some reading on the Doom9 forums (which is taking forever) and it seems like setting Quantization to 1 instead of 2 might help.

I'll try that and report back, but if anyone has anything else to add in the mean time, I'd still appreciate it.

[celtic_druid]

Well 1 is default, however you may have problems with the default overflow settings as your 2nd pass filesize looks like it must be much larger than the first. I would suggest a higher resolution and or a higher quality matrix.

[Jumbie]

Thanks.

I have VDub set up for several different coversions (batch) overnight with different settings.

I was just reading a bit about custom matrices (pretty new at encoding) and will try the 6of9 one as my bit rate is on the high side i.e. ~3000 , since the clip length is so short. Will have to use it tomorrow probably though as I'd like to see how the 4 encodes I have waiting to do tonight turn out first.

Will play with resolutions after that.

[Jumbie]

Interestingly enough, all 5 of the conversions I made last night came out with the correct size of 700 MB.
Two were slightly larger at 701 and 708, but the other three were dead on.

One was a 3-pass DivX file instead of Xvid though.