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Off-Topic: de-interlacing video

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I know that every OOT set except one (Spider's, I think?) has de-interlaced the raw video for the final DVD. Can someone tell me how to effectively do this and if it's possible with a source that was initially interlaced (e.g. DV video)? I tried to do this in Adobe Media Encoder, but it didn't seem to quite work.

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I'm forced to use TMPEGenc - under the advanced tab you can select a few deinterlace options but play with them to find what works best - and test them on your DVD player as I THINK some will not look right when on the PC or MAC but will look SWEET on the TV played through a DVD player (could this be effects of 3:2 pulldown or something?) - some bag of worms here huh?

“My skill are no longer as Mad as the once were” RiK

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Actually, I did not deinterlace my video, as it tends to create more visual errors than it solves. As Rikter can tell you, my interlaced transfer did not look bad at all.

<span class=“Italics”>MeBeJedi: Sadly, I believe the prequels are beyond repair.
<span class=“Bold”>JediRandy: They’re certainly beyond any repair you’re capable of making.</span></span>

<span class=“Italics”>MeBeJedi: You aren’t one of us.
<span class=“Bold”>Go-Mer-Tonic: I can’t say I find that very disappointing.</span></span>

<span class=“Italics”>JediRandy: I won’t suck as much as a fan edit.</span>

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A full answer to the question would be too long to post here; I'd recommend reading section 7.1.3 of the Doom9 capture guide for starters.

To summarize:
You don't have to deinterlace if your final encode is a DVD to be watched on a TV. But if your source is frame based, i.e. originally shot to film not video, then it is preferable.
If you want to watch on a PC, then you should deinterlace. However, deinterlacing truly interlaced material such as that from a DV cam may reduce quality.

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That's really helpful, Moth3r, thanks!

I used to be very active on this forum. I’m not really anymore. Sometimes, people still want to get in touch with me about something, and that is great! If that describes you, please email me at [my username]ATgmailDOTcom.

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Actually, you should never, ever deinterlace film-based material! That will screw it up royally, by blending fields that belong to different frames. Deinterlacing is irreversible: mess it up, and you'll never be able to get the full source picture back. Even some so-called "professional" transfers have been messed up in this way -- just check with anyone who deals with anime encodes (e.g. half the people on Doom9).

What you want to do with video that originated from film is perform IVTC -- inverse telecine. IVTC puts the fields back where they belong, and gets rid of those bastardized BC and CD frames completely. The result is nice, clean footage with all the original frames.

Now, for a source like DV from a camcorder, there is no choice but to deinterlace. Or, rather, to either deinterlace or not. IVTC is not an option, because the footage will have been shot at either 50 or 59.94 fields per second (i.e. 25 or 29.97 interlaced frames per second).
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Originally posted by: Karyudo
Actually, you should never, ever deinterlace film-based material!
...
What you want to do with video that originated from film is perform IVTC -- inverse telecine.
When I said "deinterlace" frame-based material, I meant by using IVTC. I guess I should have said "decomb" instead of "deinterlace" to avoid confusion. Sorry!

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No, Moth3r, I know you know what you're doing. I was about 99.something% sure you'd IVTC'ed rather than deinterlaced. I'm quite sure MBJ is also talking about not IVTC'ing, rather than not deinterlacing.

Just to make things abundantly clear:

Inverse Telecine (IVTC) is used to reverse the film-to-video procedure (called, uhh, telecining). For NTSC telecine, the 24fps film frames (e.g. A B C D x6) are converted to 29.97fps video frames (e.g. AA BB BC CD DD x6) using 3:2 (or 2:3) pulldown. You'll note that because both video fields come from the same film frame, AA, BB, and DD look 'perfect', while BC and CD will show combing because they combine fields from two different film frames. This 3:2 cadence is quite predictable, so it's possible to drop a B and D field to get AA BB CC DD, and from that a nice progressive A B C D -- the same thing that was input. PAL telecine does 2:2 pulldown, so it's much easier to make progressive -- there are no annoying hybrid frames to deal with.

Deinterlacing is used to make field-based material (e.g. just about anything shot with a video camera, or produced for TV) progressive. Video cameras record separate, unique fields at twice the nominal frame rate (i.e. 59.94fps for NTSC and 50fps for PAL), so displaying both fields of a given video frame at the same time will show distracting combing effects. Unlike IVTC, it is impossible to reverse one procedure to recover the original whole frame, because it never really existed in the first place. The two fields come from two different instances in time. The best you can do is to have your computer do a bunch of math and try to smooth out the combing -- sort of picking an intermediate time between the two fields, say. This necessarily destroys some of the original information, but usually the tradeoff is worth it. That is, the end result looks smoother and easier to watch on a progressive display or display format than would the original video.

Decombing is deinterlacing. However, in AviSynth, Donald Graft's (aka Neuron2) DeComb is probably the best package that does IVTC. This is because DeComb is highly adaptive, and can do both deinterlacing and IVTC. Telecide() and Decimate() together, with appropriate parameters, can correctly IVTC film material and deinterlace field-based material even when they appear in the same clip. Doesn't happen that often with movies on LD, but it can happen a lot on TV shows, or anime.

So, to sum up, for LD OT conversions, IVTC is what you want. Stay away from deinterlacing!
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"I'm quite sure MBJ is also talking about not IVTC'ing, rather than not deinterlacing."

"I said what I meant, and I meant what I said....." (10 points to whoever can finish that sentence. )

I IVTC'ed my transfer, but everything I saw about deinterlacing said "stay away", and for good reason.

<span class=“Italics”>MeBeJedi: Sadly, I believe the prequels are beyond repair.
<span class=“Bold”>JediRandy: They’re certainly beyond any repair you’re capable of making.</span></span>

<span class=“Italics”>MeBeJedi: You aren’t one of us.
<span class=“Bold”>Go-Mer-Tonic: I can’t say I find that very disappointing.</span></span>

<span class=“Italics”>JediRandy: I won’t suck as much as a fan edit.</span>

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Originally posted by: MeBeJedi
"I said what I meant, and I meant what I said....." (10 points to whoever can finish that sentence. )
"an elephant is faithful, 100 percent."

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* DING * DING * DING * DING * DING

<span class=“Italics”>MeBeJedi: Sadly, I believe the prequels are beyond repair.
<span class=“Bold”>JediRandy: They’re certainly beyond any repair you’re capable of making.</span></span>

<span class=“Italics”>MeBeJedi: You aren’t one of us.
<span class=“Bold”>Go-Mer-Tonic: I can’t say I find that very disappointing.</span></span>

<span class=“Italics”>JediRandy: I won’t suck as much as a fan edit.</span>

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LOL

<span class=“Italics”>MeBeJedi: Sadly, I believe the prequels are beyond repair.
<span class=“Bold”>JediRandy: They’re certainly beyond any repair you’re capable of making.</span></span>

<span class=“Italics”>MeBeJedi: You aren’t one of us.
<span class=“Bold”>Go-Mer-Tonic: I can’t say I find that very disappointing.</span></span>

<span class=“Italics”>JediRandy: I won’t suck as much as a fan edit.</span>