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morca007
20th December 2008, 20:52
I'm currently working on backing up Vanishing Point (Retail NTSC) using x264, and am having some trouble.
In some scenes it looks telecined (standard 3p, 2i pattern), in others there are frames which are more combed than others, but all have residual combing (creating a pattern of 3 slightly combed frames, 2 full interlaced). However, I'm loathe to call it hybrid content as: A. It doesn't appear fully interlaced in any scenes, B. The film was made far before the advent of digital editing (effects, etc.)

I've tried IVTC and the residual combing remains (as expected), and also tried straight up deinterlacing (Yadifmod + nnedi), which just seems wrong.

DGIndex log:
Stream Type: MPEG2 Program
Profile: main@main
Frame Size: 720x480
Display Size: 720x480
Aspect Ratio: 16:9 [3]
Frame Rate: 29.970030 fps
Video Type: Film
Frame Type:
Coding Type:
Colorimetry:
Frame Structure:
Field Order:
Coded Number:
Playback Number:
Frame Repeats:
Field Repeats:
VOB ID: 2
Cell ID: 3
Bitrate:
Bitrate (Avg):
Bitrate (Max):
Audio Stream: 80: AC3 2/0 192
Audio Stream: 81: AC3 2/0 192
Audio Stream: 82: AC3 2/0 192
Audio Stream: 83: AC3 2/0 192
Audio Stream: 84: AC3 2/0 192
Timestamp: 0:09:22
Elapsed: 0:00:00
Remain: FINISH
FPS:
Info:

Source Sample (14.7mb) (http://www.mediafire.com/?sharekey=faadd4280678f8e734ec03e3e223c21f9aa9fe45169b21ee)

Any ideas what the combing is?
Thanks.

Edit: Sorry for the double post.

neuron2
20th December 2008, 23:56
Strangely, your sample is bitwise identical to the sample posted in this thread:

http://forum.doom9.org/showthread.php?p=1225169#post1225169

So I guess I will just refer you there. :)

morca007
21st December 2008, 00:37
Thanks, seems I've got some reading (and testing) to do.

Edit: So, as far as I gather, the blended fields originated during a bad NTSC/PAL transfer. Is there anything I can do to fix this in avisynth?
Using, say, telecide(blend=true) results in combing, and a soft picture.
Deinterlacing and then using SRestore to bring it to 23.976fps kills details.

manono
21st December 2008, 16:01
So, as far as I gather, the blended fields originated during a bad NTSC/PAL transfer.
No, there's nothing PAL about it. It was field-blended from 23.976->29.97, rather than being telecined. It stayed NTSC all the way. The base framerate is 23.976fps rather than 24.975fps, as would be the case had it started life as PAL.

I had my best luck with:

Yadif(Mode=1,Order=1)
CDeblend()
BlendBob()
TDecimate()

You can try another and slower bobber, but as long as field-blending is involved you'll never get it to the way it would have been had the DVD production company done it right in the first place. All those diagonal lines on the cars will always be aliased.