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View Full Version : Some interlacing in credit roll


StickHorsie
13th March 2013, 17:13
What would be the best way to deinterlace this part with avisynth (see snippet) to get rid of the interlacing AND to keep it rolling as smoothly as the original? I've tried several deinterlacers, but the results always seem to be a bit jittery (like: small jump, small jump, larger jump, small jump etc) even though I keep the frame rate at 29.97fps.

snippet: http://www.mediafire.com/?t9dxtlvgj66mz73 (7.99 MB)

PS. yes, I own the DVD

paradoxical
13th March 2013, 17:33
What would be the best way to deinterlace this part with avisynth (see snippet) to get rid of the interlacing AND to keep it rolling as smoothly as the original? I've tried several deinterlacers, but the results always seem to be a bit jittery (like: small jump, small jump, larger jump, small jump etc) even though I keep the frame rate at 29.97fps.

snippet: http://www.mediafire.com/?t9dxtlvgj66mz73 (7.99 MB)

PS. yes, I own the DVD

If you want the same smoothness you need to do double-rate deinterlacing and keep it at 60p. Otherwise, it will be jittery because your throwing away half the temporal motion.

StickHorsie
13th March 2013, 17:45
My intention was to get something in the 23.976fps to 29.97fps range and to slow it down (if necessary) to the same speed as rest of the movie after deinterlacing and decimating (23.976fps), which all works perfectly well except for the snippet part.

If I wind up with a 60fps part, I can of course still slow it down to 23.976fps but then it would be a tad long. ;)

Is there really no way to get this to run smoothly at 29.97 fps? *sad puppy eyes*


What I did was this:

v1=Trim(0,314175).Telecide(guide=1,post=2,vthresh=25).Decimate(5) # the movie
v2=Trim(314381,315064).Telecide(guide=1,post=2,vthresh=25).AssumeFPS(24000,1001) # credit roll; I also tried guide=2
v3=Trim(315065,318853).Telecide(guide=1,post=2,vthresh=25).Decimate(5) # more credits, but no rollin'
UnalignedSplice(v1,v2,v3)

Everything is OK, I even get the intended number of frames, only v2 is a bit jitterish

paradoxical
13th March 2013, 18:03
You're dealing with purely interlaced credits. If you single-rate deinterlace it it will not be as smooth for the reason I told you.

manono
13th March 2013, 21:26
Why do the credits even have to be 23.976fps? If for DVD you can keep them interlaced. If for something else you can use a container that supports VFR and at least keep them 29.97, if not interlaced.

Why telecide them if they were never telecined in the first place? Use a regular deinterlacer. QTGMC can add a motion blur to make them appear to play more smoothly at 29.97fps. It's a bobber so add a SelectEven afterwards to get it back to 29.97fps.

Your V2 is more jumpy not only because you made it progressive, but because you slowed it down (a very bad idea, in my opinion), thus emphasizing the jerkiness.

StickHorsie
14th March 2013, 15:27
You're dealing with purely interlaced credits. If you single-rate deinterlace it it will not be as smooth for the reason I told you.

When I bobbed the part to see what the fields looked like, it turned out to be even too much FUBAR for that... it made a little jump every 3rd or 4th field (with no discernable pattern alas), which fields also had a better quality than the others. So I tried Bob + SelectEvery(2000,140,144,147,150,154,157,161,164,168,171,174,...) (all the "good" fields), hoping I could maybe interpolate the missing frames, but it still didn't look good enough.

So I cut my losses, completely remade the part (pasted screenshots together, replaced the text & rolled it with Avisynth's Animate), and now it's totally clean, 23.976fps and in far less time than I've already spent on it. :D

New script (which, to my utter surprise, worked right the first time):
v1=Trim(0,314091).Telecide(guide=1,post=2,vthresh=25).Decimate(5)
v2=AVISource("G:\DVD\GLAEQ\newscroll_720x480.avi") #Q=2, grayscale, no B-frames
v3=Trim(315067,318853).Telecide(guide=1,post=2,vthresh=25).Decimate(5)
UnalignedSplice(v1,v2,v3)

It's just that I had hoped there was some easy MagicCreditRollDeinterlace(mode="SalesBinDVD",quality="perfect",24000,1001) plugin that I had overlooked...

Why do the credits even have to be 23.976fps? If for DVD you can keep them interlaced. If for something else you can use a container that supports VFR and at least keep them 29.97, if not interlaced.

I'm not backing up to DVD but to both crf=18 .mp4 (for best quality) and .avi (because my decrepit standalone player & my decrepit too-old-to-steal-so-safe-to-bring-during-long-hospital-stays laptop can't play mp4s) without letterboxes, pillarboxes and other black stuff around the image. I always do the avi first and if it's OK, I run exactly the same script with MeGUI for the .mp4.

A VFR mp4 would be a possibility, yes... I'll keep that in mind for a backup that's really worth it.

Why telecide them if they were never telecined in the first place?

Just one of the gazillion things I've tried. I was in the "try random stuff / you never know" stage, which 1 out of 20 times even produces decent results. Sometimes.

Use a regular deinterlacer. QTGMC can add a motion blur to make them appear to play more smoothly at 29.97fps. It's a bobber so add a SelectEven afterwards to get it back to 29.97fps.

Thank you, nice tip, I'll try that on my next DVD with interlaced credits (there's still a LOT).

Your V2 is more jumpy not only because you made it progressive, but because you slowed it down (a very bad idea, in my opinion), thus emphasizing the jerkiness.

I also tried it without telecide. If it's smooth enough at 29.97fps, it should also be smooth enough if I slow it down to 23.976fps (instead of decimating, which would make it REALLY jumpy). True, that part would become a bit longer then, but I snipped off a bit from the end of v1, which was all black anyway, to compensate for the longer v2.

Anymoo, thank you all for your time! :D