Convert 14.985 to 29.97fps?

[reboot]

I have a bunch (650 meg) worth of avi's, all recorded at 14.985fps from some capture device.
In order to make compliant SVCD's, I would like to double that to 29.97fps.
If I let TMPGEnc do it, the video is jerky, and output quality sucks. Even using the smallest (89 meg) avi, and max bitrate, CQ-VBR 85, it sucks.
I've read the guides, which are great for PAL to NTSC etc., but nothing addresses the problem I have.
Can I simply let VirtualDub do it? I see the settings are there.
Short of converting and burning a bunch of (possibly) wasted CDR's, is there any good way to do it, with predictable results?
The avi's play fine on the computer, in WMP9, WinDVD, and WMP6.4, and the resulting mpegs play fine as well, but when burned and played on my standalone, look like they were recorded with a plastic toy camera.

Edit: I tried encoding with Canopus, same result. I tried using DVD2SVCD (in AVI2SVCD mode) same result. I tried using DVD2SVCD with CCE, and got the chipmunks doing the audio

[redwudz]

I have converted 15fps to 29.97 with Virtualdub and had decent results. I admit I never tried to play it in a standalone player. The video I had was from a still digital camera in video mode.

[reboot]

I think this video came from a Logitech Quickcam Traveller, which is basically a still cam, that will do video when hooked to the computer.
It's 352x240, designed probably for VCD, but I'm making SVCD to retain what little quality there is
As a test, I converted a vid to 29.97fps in VirtualDub, and it plays extremely well on the computer.
Now to convert it, and we'll see how it turns out.
I set up Canopus, and it's figuring about 8 hours (2 pass VBR+normalize filter) at a bitrate of 1500 avg.
Maybe i can cut that down in TMPGEnc or CCE.

[au7usa]

How about AVISynth?

(Load the clip twice, and then shuffle the deck)

clip1=AviSource (c:\xxx.avi")
clip2=AviSource (c:\xxx.avi")
Interleave (clip1, clip2)
AssumeFPS (29.97)

.......or something like this.

[D_Knife]

How about MotionPerfect from Dynapel
http://www.dynapel.com/index.shtml
it's only in the downloads area now - I think it's discontinued
uses math warping to build new composite frames together

[secretagent]

stoik video converter in the tools section

[reboot]

Thankyou all...after messing with it for a bit, I got VirtualDub to do it, rather quickly, and clean too
Converted it in DVD2SVCD using CCE, VBR 3 pass, and it's excellent.