How can I extract and recombine interlaced fields?

Author: jephyork
Date: 18-Mar-2017, 7:53 PM

Author: jephyork
Time: 18-Mar-2017 7:53 PM
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I’m working with interlaced video, and I want the ability to treat the individual fields that make up each frame, as if they were frames.

I want to be able to separate each frame into its two fields – to step through the fields individually – to delete some, rearrange some, change their order – and most importantly, I want the ability to recombine an upper field and a lower field to form a single frame again.

I DO NOT want software that interpolates the missing data to make each field into a full frame by itself. I want the fields to remain fields, with half their visual data missing, until I decide to recombine them manually into frames.

Is this possible?

I use a Mac and currently edit on Final Cut Pro. My source is a commercial DVD, a TV show shot on film but edited on video, presented at 29.97 interlaced.

Help would be greatly appreciated! Thanks in advance! 😃

Author: Moth3r
Time: 18-Mar-2017 8:52 PM (Edited)
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Not sure if it’s possible to run Avisynth on a Mac via Wine, but this is easily accomplished using SeparateFields() and Weave().

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Author: jephyork
Time: 18-Mar-2017 9:08 PM
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Thanks! Hmm. AviSynth is script-only, right? No GUI or timeline-based editing ability?

I’m hoping to get the frames out on an editing timeline so I can, say, delete one, swap two others, etc. Just poke at and mess with them ad nauseum. I have no idea how to do any of that with scripts.

Are you suggesting that I split them in AviSynth, then import that into another program and edit it – then export it and weave the fields back together in Avi as a final step?

Alternately: do you know if this is possible in AfterEffects? I believe I read that it has a field-separating ability, but I don’t know much more.

Author: schorman13
Time: 19-Mar-2017 11:24 AM (Edited)
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You can do that within virtualdub using the ivtc filter. You can mess around with the settings without having to reload your file/script.

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Author: jephyork
Time: 20-Mar-2017 2:34 PM (Edited)
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Thanks! I’ll try to get either/both of them working on Wine, and see what I can do.

Can either program handle a .VOB file (ripped from the DVD), or do I need to transcode to some other format/codec?

And is either program lossless? The ultimate end goal is to reconstruct the original frames and up-res this to 720p, so I’m trying not to degrade the original image in any way. (That’s why I’m avoiding interpolation of missing fields…)

…Hmm. Are there forums dedicated to AviSynth and VirtualDub out there somewhere, so I can ask all my dumb newbie questions?