Preserve 29.97 frame rate?

[colonel0812]

I am doing an edit/upscale restoration, working with Star Trek: Deep Space Nine DVDs. Like several shows at the time, the show was shot on film and edited on video. This results in an inconsistent pulldown cadence from cut to cut. This isn't an issue when watching it at the original broadcast 29.97fps.

The original frame rate of the VOB is 29.97. This preserves all the frames. But so far, no matter how I demux it, import it, or convert it, it gets detelecined to 23.976fps, resulting in a lot of interlacing, or at best, reduced-quality deinterlacing and frame blending. The only way it looks right is if I play to original VOB in VLC.

How can I convert this straight and preserve the DVD's 29.97fps without it getting detelecined?

[ProWo]

Get the video only with pgcdemux and post a mediainfo report from the m2v here

[manono]

The original frame rate of the VOB is 29.97.

The VOB, yes. But if shot on film that's not the 'source' framerate. An IVTC should return it to 23.976fps without the interlacing you're complaining about.

How are you performing the IVTC? You mention 'detelecine' so maybe you're using Handbrake? Yes, a sample is needed. Me, I'd cut it from a VOB using DGIndex, 10 seconds or so with steady motion.

[colonel0812]

Get the video only with pgcdemux and post a mediainfo report from the m2v here

General
Complete name : E:\Deep Space Nine\Season 3\S03E01 The Search Part I\VideoFile.m2v
Format : MPEG Video
Format version : Version 2
File size : 1.70 GiB
Duration : 45 min 28 s
Overall bit rate mode : Variable
Overall bit rate : 5 341 kb/s

Video
Format : MPEG Video
Format version : Version 2
Format profile : Main@Main
Format settings : CustomMatrix / BVOP
Format settings, BVOP : Yes
Format settings, Matrix : Custom
Format settings, GOP : Variable
Duration : 45 min 28 s
Bit rate mode : Variable
Bit rate : 5 341 kb/s
Maximum bit rate : 9 800 kb/s
Width : 720 pixels
Height : 480 pixels
Display aspect ratio : 4:3
Frame rate : 29.970 (30000/1001) FPS
Standard : Component
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Compression mode : Lossy
Bits/(Pixel*Frame) : 0.516
Time code of first frame : 00:59:59;00
Stream size : 1.70 GiB (100%)
Color primaries : BT.601 NTSC
Transfer characteristics : BT.601
Matrix coefficients : BT.601

Text
ID : CC3
Format : EIA-608
Bit rate mode : Constant
Stream size : 0.00 Byte (0%)
CaptionServiceName : CC3

[colonel0812]

The original frame rate of the VOB is 29.97.

The VOB, yes. But if shot on film that's not the 'source' framerate. An IVTC should return it to 23.976fps without the interlacing you're complaining about.

How are you performing the IVTC? You mention 'detelecine' so maybe you're using Handbrake? Yes, a sample is needed. Me, I'd cut it from a VOB using DGIndex, 10 seconds or so with steady motion.

Yeah, in this instance when I say "source" I'm referring to the DVD. And yeah by "detelecine" I mean IVTC. The problem is that since the show was edited on video and not on film, each edit point in the video starts at a different point in the pulldown cadence. Like this:


[Attachment 54492 - Click to enlarge]

The IVTC process is happening automatically no matter what I use to import or convert it. I'm trying to figure out how to NOT perform IVTC.

I'll work up a comparison sample.

[davexnet]

Post a sample of the original VOB showing the transition.

How can anybody given any advice about your workflow when you haven't stated
anything about your program or settings?

[manono]

I'll work up a comparison sample.

No one wants a "comparison sample". Just 10 well chosen seconds direct from the VOB with steady motion. If you use DGIndex to do the cutting, you'll get an M2V for upload here.

[ProWo]

Try my clever FFmpeg-GUI, rip directly from the DVD and encode with x264, CRF 23, FPS 29.97, DAR 4:4, 720x480.

[colonel0812]

Okay here's a sample, and I've scaled it up and slowed it down so you can really see the interlacing.
On the left is a 60fps screen capture of VLC playing the straight VOB file, and Codec Information says it's 29.97fps. On the right is the same VOB file imported straight into Premiere Pro, which says it is 23.976fps.

https://youtu.be/bW8UNWLc49Y

In VLC, deinterlacing is set to auto, turning it off results in the same artifacts as the right.
Turning on deinterlacing in Premiere works but results in reduced quality, blended frames and transitions.

[smrpix]

I am doing an edit/upscale restoration.....How can I convert this straight and preserve the DVD's 29.97fps without it getting detelecined?

You may not want to convert it straight. Depending on the restoration work you are planning you may want to double the frame rate to 59.94 which will preserve each field of the telecined material regardless of cadence.

[colonel0812]

I'll work up a comparison sample.

No one wants a "comparison sample". Just 10 well chosen seconds direct from the VOB with steady motion. If you use DGIndex to do the cutting, you'll get an M2V for upload here.

Ok, I'll get that.

[colonel0812]

Ok see if this works.

[colonel0812]

You may not want to convert it straight. Depending on the restoration work you are planning you may want to double the frame rate to 59.94 which will preserve each field of the telecined material regardless of cadence.

That may be exactly what I want to do. But so far nothing is preserving each field no matter what frame rate I choose, it all seems to first do IVTC.

[colonel0812]

Ok I think I figured it out. In DGIndex, if I demux the entire VOB, it results in an IVTC 23.976 video. But if I trim off a few frames at the beginning, I get the straight 29.97. It solves my immediate problem, but does anyone know why that would happen?

[davexnet]

check video/field operation - honor pulldown flags is the normal setting.
Are you demuxing the video for a reason? Usually, save project, then use the .d2v in an Avisynth script

[colonel0812]

Ok I was wrong. When I get 29.97 it's actually sped up from the IVTC'd 23.976. This is a pain in the but, lol.

[manono]

In DGIndex, if I demux the entire VOB, it results in an IVTC 23.976 video.

No, it doesn't. That sample you uploaded was mostly shot on film with a few video elements in it. It IVTC's reasonably well.

MPEG2Source("test.d2v")
tdeintted = QTGMC(FPSDivisor=2)
tfm(clip2=tdeintted).tdecimate()

You still haven't said what you've been using so far, but you'll need AviSynth for a project like this.

[jagabo]

Always use DgIndex in Honor Pulldown Flags mode (except for the rare occasion when a source is 100 percent film) then IVTC (or whatever) in AviSynth.

Your source was shot on film, telecined to 30i, then some effects were added as 30i (the shaking, for example) so it cannot be IVTC'd perfectly. It's not really noticeable at normal playback speed though (at least in that short clip).

AviSynth Script:

Mpeg2Source("Sample.demuxed.d2v", Info=3) 
TFM() 
TDecimate()

[colonel0812]

I guess it's time to start learning AviSynth! I know nothing about it, is there a primer y'all would suggest I start with?

[manono]

You go to the AviSynth homepage and start reading.

You do know, don't you, that others with more AviSynth knowledge are already deep into doing what you want to do?

https://forum.videohelp.com/threads/396652-Deinterlacing-Deep-Space-Nine-NTSC#post2583987

and especially:

https://forum.doom9.org/showthread.php?t=181209

By reading there you'll come across lots of sample scripts along the way.