How to speed up video selection in VirtualDub?

[BRFNGRNBWS]

I am using VirtualDub to edit a video, and I want to speed up just the part of the video I have selected. I have seen how to speed up the whole video altogether, but I want to do just my selection. I found a method where you save your selection as a separate file, and then speed it up, but I don't want to do that, either. Is there any way to do this, or is there a plug-in or something? Thanks.

[redwudz]

'Conditional Filtering' for VD should let you select just a portion of the video to apply a filter to:
http://web.archive.org/web/20050405002942/http://wwwtcs.inf.tu-dresden.de/~dc1/conditional

And welcome to our forums.

[sambat]

This was discussed at the defunct VirtualDub Forum.

http://forums.virtualdub.org/index.php?act=ST&f=4&t=21806&st=0

Here's the commented script for AviSynth.

## speed change test:
## the frame numbers reference the original source, not the numbers seen in VirtualDub when served from Avisynth.
## 130% speed from frame 0 to frame 500
## 200% speed from frame 501 to frame 1000
## normal speed to end of video
## float 'factor' ('factor' is the variable) value is 1.3 or 2 (130% or 200%) 'float' means floating point.
## 'framerate' varies using the value 'factor'
## the varying audio tempo retains pitch by referencing 'factor'
## 'ChangeSpeed' is a user defined function that's called twice for frames 0-500 and 501-1000.

V=AviSource ("video.avi")

return ChangeSpeed(Trim(V, 0, 500), 1.3)
\ + ChangeSpeed(Trim(V, 501, 1000), 2)
\ + Trim(V, 1001, 0)

function ChangeSpeed(clip c, float factor )
{
oldRate = FrameRate(c)
newVid = AssumeFPS(c, oldRate * factor)
return AudioDub(ChangeFPS(newVid, c), c.TimeStretch(tempo=100*factor))
}