Interlacing progressive full frame video

[wonkey_monkey]

Hi all,

I'm working on a project for standards-converting PAL to NTSC. The final stage is to re-interlace 59.94fps progressive video, but I'm having trouble.

Weave() is no good, because it takes the already full vertical resolution and doubles it. If I PointResize to 50%, I lose half my resolution because it amounts to weaving even lines with even lines.

What I need to do is weave the even lines of frame x with the odd lines of frame y. Another way to achieve this would be to somehow shift every other frame up by 1 pixel, PointResize to 50%, then Weave().

Sorry if this has been answered before, or if there's a filter out there to do it, but most of the AviSynth stuff I've found on the web concentrates on de-interlacing.

Here's my script so far:

mpeg2source("football.d2v")
dgbob(1)
bilinearresize(720,480)
changefps(59.94)

David

[mg262]

So you want to reverse the effect of a bob? Try this...

AssumeTFF()
SeparateFields()
#have fields in order 1t 1b 2t 2b 3t 3b 4t 4b 5t 5b
SelectEvery(4, 0, 3)
#have fields in order 1t 2b 3t 4b 5t 6b
Weave()

[wonkey_monkey]

Thanks mg262, that does (almost) exactly what I want. Because output has to be TFF for DVD, I changed it to:

SelectEvery(4, 1, 2)

Thanks!

David

[scharfis_brain]

@david...
the output of mg262's filterchain already WAS TFF!

changing 4,0,3 to 4,1,2 will output BFF

[wonkey_monkey]

Ah, I didn't spot his AssumeTTF() so I compensated for it by changing the SelectEvery().

David

[mg262]

I edited AssumeTFF() in about 60 seconds after the original post... maybe you read it in the interval.

I was under the impression that DVDs could handle bottom frame first content as well, with the appropriate flag set... but I've never tried it.

[wonkey_monkey]

I've had BFF set (it's the default) in the MPEG encoder since I installed it, but it doesn't seem to make any difference. I still have to supply TFF video for it to play back correctly on a DVD player.

David