Problem with interlace video and filters

[Colp]

Hi,

I'm new in using avisynth and a problem with probably simple
answer occured - how is avisynth handling interlaced video (DV)
when I want to use any filters?
Whatever filter (for example AddBorders) I'm using -
movement in a video is not so smooth as in original.
What should I do to preserve original smooth movement?

[scharfis_brain]

What should I do to preserve original smooth movement?

only adding an even numbered count of lines.
assuring the correct encoding field order (BFF [Bottom Field First] for DV-Video)

separating the Fields before doing the filtering.

like:

separatefields()
yourfilters()
weave()

be sure noticing, that the height is lowered when using separatefields()

the best (& slowest) mehtod:

dgbob(order=0)
yourfilters()
separatefields()
selectevery(4,0,3)
weave()