720p --> 576i

[genak]

I'm trying to convert a 720p video to 576i using the following AVI Synth script:

AssumeTFF()
Lanczos4Resize(720,576)
SeparateFields.SelectEvery(4,1,2)
ConvertToYUY2()
Weave()

But this produces a slight problem: the source video in question consists of an "interlaced" part (i.e. every frame is different) and a "deinterlaced" part (i.e. only every other frame is different - the broadcaster does it to create a crappy fake-film effect).

So, surely, in the final 576i video the "deinterlaced" part should appear progressive...? Except it doesn't, it looks like the attached image.

I realise it should play back fine, but when the final product looks like the attached image a much higher bitrate is required due to the extra detail. So my question is how can I rewrite the script to avoid this?

[jagabo]

You are probably just out of phase on the "deinterlaced part". Ie, when you get to the deinterlaced part your sequence isn't:

1 1 2 2 3 3 4 4...

it's:

x 1 1 2 2 3 3 4 4...

Where x is one last frame from the earlier section. So your combining fields from the wrong pairs of frames. You have to break the video up into two parts with Trim().

[manono]

You could do a field match without the default post processing to get the shifted fields part of it back in phase, something like:

TFM(PP=0)#from TIVTC

after the resize and reinterlace. That should make the progressive parts progressive again and leave the interlaced parts alone. I think.