[MPlayer-users] deinterlacing help

[D Richard Felker III]

I've run into quite a few broken interlaced files that have fields in
the following pattern: 122112211221... i.e. field 1 appears on lines
that are 0 or 3 mod 4, and field 2 appears on lines that are 1 or 2
mod 4. I have no idea how the files came to be like this. Apparently
it's some broken scale plugin for VirtualDub, which scaled PAL DVD
down from 720x576 to 400x320 and made stupid decisions about how to
handle interlacing. In any case, the new vf_il filter has helped
greatly in diagnosing the problem, but I still don't know how to fix
it. -vop il=ic,pp=lb,il=dc cures the interlacing, but of course that
also mixes lines that don't belong next to each other, resulting in
some new ugly artifacts.

Are there any existing filters that might clean up this mess for me?
Or might it be possible to tweak one of them to do what I want? I've
had these bad files for quite some time now, and now that the vf_il
filter has made the nature of the problem clear (via -vop il=dc,il=dc
separating the image into four "fields"), I'm hoping I might finally
be able to fix them!

Rich