Writing a script to de-interlace only part of a source?

[Matthew]

Using avisynth 2.5 and CCE, I'm backing up an episodic PAL DVD that is progressive, except for the credits, which are interlaced.

First up I tried what I did in the past with this situation, encoding the stream as interlaced (this doesn't matter with PAL progressive stuff, it's just a flag) and zigzag. However, as I have capped the credits bitrate at 2000 (average bitrate is only 3175) and they have a graphical background they look rather bad. The poor encoding of the original DVD doesn't help either (shame on the BBC). So I'll de-interlace in order to up the quality a little.

There's 5 discs with 3 eps on each, so instead of encoding the 2 parts of the video separately and merging, I'd like to write a script that serves up the progressive part and then uses FieldDeinterlace()on the credits part only.

Is there some way to do this? i.e. specify filters to be applied only to a certain portion of the source.

I did search but it's hard when one doesn't know what words to input.

Thanks :)

[mf]

ApplyRange (http://www.avisynth.org/index.php?page=Animate) should do what you want. However, it is pretty buggy in its usage (not taking filters without arguments, yawn, etc), so I'd recommend JDL_ApplyRange (http://www.avisynth.org/stickboy/) instead.

[Matthew]

Thanks very much for the reply, I'll see if I can figure this out =)