video size problem

[tomchook]

Hello,
I'm using VirtualDub-MPEG2 1.6.19 on Windows Vista and I'm compressing a video file I had on my Canon IXY 900IS digital camera.
The original file size is 90.5MB
In VirtualDub the video is set on full processing mode, and I set the compression to Xvid MPEG4 codec without special configuration.
The output file is 33.5MB
When I add a filter of 2:1 reduction (high quality), the output file is 7.53MB

It just doesn't seem reasonable that if I reduce it by 2 it would reduce the file 4 times.. Or maybe I'm just really bad at math?

Anyway, what I would like is to have the xvid compression, without 2:1 reduction, and that the file would be double as the small file (let's say.. 15MB). I know there's a possibility to set the output file size, but I think that would damage the quality, wouldn't it?

Is there any solution for this?
Thanks!
Tom

[Baldrick]

What xvid settings are you using now? If you use target quantizer then try lower the number.

But does the video look good? Then I don't see any point making it bigger.

[olyteddy]

By 'When I add a filter of 2:1 reduction (high quality), ' do you mean shrinking the video from, say 640X480 to 320X240? If so, then that is a 4X reduction in area (2X horizontal, 2X vertical)...

[jagabo]

Yes, the 2:1 reduction filters in VirtualDub reduce the size in both dimensions. So an output 1/4 the size is expected when using Xvid in target quantizer mode.

And by the way, those filter are outdated. Use the Resize filter in Lanczos3 mode instead.