NTSC DVD jerky playback - Avisynth Filter - Help

[nbarzgar]

Hello All,

I've tried converting a DVD of an old movie I own using Avisynth and filters.

The original DVD plays at 29.97 fps, already jerky on my standalone Blu-Ray player (recent Sony) as well as on my Windows 10 computer (2,6 Ghz CPU, 8GB RAM, Nvidia Geforce GT 1030 graphics).

I know that the mpeg2 stream is reported as being progressive, but my impression was when loading via DGIndex and Avisynth into VirdtualDubMod that separating fields had an effect...so it seems to be interlaced...? Hybrid?
(Find MediaInfo report of .VOB below)

I saved it to my HDD and thought, filtering (determining field order, tried Telecide, SeparateFields and Select..., deinterlacing with Kerneldeint: mapping on to determine threshold) so far to no avail.
I also did some research but din't find any more helpful posts or ideas.

I attach a sample clip to this post and hope someone here can help me figure out what's going on.

Is it hopeless because the transfer or the DVD production process are at fault?

Thanks for any help in advance!

BR
nbarzgar

General
Complete name                            : D:\Video\DVD\Omar Khayyam\video_ts\VTS_01_1.VOB
Format                                   : MPEG-PS
File size                                : 1 024 MiB
Duration                                 : 26 min 0 s
Overall bit rate mode                    : Variable
Overall bit rate                         : 5 506 kb/s

Video
ID                                       : 224 (0xE0)
Format                                   : MPEG Video
Format version                           : Version 2
Format profile                           : Main@Main
Format settings                          : BVOP
Format settings, BVOP                    : Yes
Format settings, Matrix                  : Default
Format settings, GOP                     : M=3, N=15
Duration                                 : 26 min 0 s
Bit rate mode                            : Variable
Bit rate                                 : 5 013 kb/s
Maximum bit rate                         : 9 000 kb/s
Width                                    : 720 pixels
Height                                   : 576 pixels
Display aspect ratio                     : 4:3
Frame rate                               : 25.000 FPS
Standard                                 : PAL
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Compression mode                         : Lossy
Bits/(Pixel*Frame)                       : 0.483
Time code of first frame                 : 00:00:00:00
Time code source                         : Group of pictures header
GOP, Open/Closed                         : Open
GOP, Open/Closed of first frame          : Closed
Stream size                              : 932 MiB (91%)

Audio #1
ID                                       : 189 (0xBD)-128 (0x80)
Format                                   : AC-3
Format/Info                              : Audio Coding 3
Muxing mode                              : DVD-Video
Duration                                 : 25 min 59 s
Bit rate mode                            : Constant
Bit rate                                 : 192 kb/s
Channel(s)                               : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 48.0 kHz
Frame rate                               : 31.250 FPS (1536 SPF)
Bit depth                                : 16 bits
Compression mode                         : Lossy
Stream size                              : 35.7 MiB (3%)
Service kind                             : Complete Main

Audio #2
ID                                       : 189 (0xBD)-129 (0x81)
Format                                   : AC-3
Format/Info                              : Audio Coding 3
Muxing mode                              : DVD-Video
Duration                                 : 25 min 59 s
Bit rate mode                            : Constant
Bit rate                                 : 192 kb/s
Channel(s)                               : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 48.0 kHz
Frame rate                               : 31.250 FPS (1536 SPF)
Bit depth                                : 16 bits
Compression mode                         : Lossy
Stream size                              : 35.7 MiB (3%)
Service kind                             : Complete Main

Menu

[jagabo]

That clip has both missing frames and duplicate frames. And there is no consistent pattern to take advantage of. It's going to be very difficult to fix.

[nbarzgar]

That clip has both missing frames and duplicate frames. And there is no consistent pattern to take advantage of. It's going to be very difficult to fix.

Thanks for the hint.
Any ideas how I could proceed?

[jagabo]

Some duplicate frames are simply duplicates. Those can be removed with DeleteFrame().

Other duplicates are there taking the place of a missing frame, ie instead of 1 2 3 4 5 you have 1 2 2 4 5. The second of the duplicates can replaced with motion interpolated between the surrounding frames. I created a function called ReplaceFramesMC() that does that. It was based on a function originally called RX().

In places where there are missing frames you can use InsertFramesMC() (also based on the filter originally called RX()) to create a new frame with motion interpolated between the frame before and the frame after.

######################################################
[
function ReplaceFramesMC(clip Source, int N, int "X")
{
  # N is number of the 1st frame in Source that needs replacing. 
  # X is total number of frames to replace
  #e.g. ReplaceFramesMC(101, 5) would replace 101,102,103,104,105 , by using 100 and 106 as reference points for mflowfps interpolation
 
  X = Default(X, 1)

  start=Source.trim(N-1,-1) #one good frame before, used for interpolation reference point
  end=Source.trim(N+X,-1) #one good frame after, used for interpolation reference point
 
  start+end
  AssumeFPS(1) #temporarily FPS=1 to use mflowfps
  
  super = MSuper(pel=2, hpad=0, vpad=0, rfilter=4)
  backward_1 = MAnalyse(super, chroma=false, isb=true, blksize=16, searchparam=3, plevel=0, search=3, badrange=(-24))
  forward_1 = MAnalyse(super, chroma=false, isb=false, blksize=16, searchparam=3, plevel=0, search=3, badrange=(-24))
  backward_2 = MRecalculate(super, chroma=false, backward_1, blksize=8, searchparam=1, search=3)
  forward_2 = MRecalculate(super, chroma=false, forward_1, blksize=8, searchparam=1, search=3)
  backward_3 = MRecalculate(super, chroma=false, backward_2, blksize=4, searchparam=0, search=3)
  forward_3 = MRecalculate(super, chroma=false, forward_2, blksize=4, searchparam=0, search=3)
  MBlockFps(super, backward_3, forward_3, num=X+1, den=1, mode=0)

  AssumeFPS(FrameRate(Source)) #return back to normal source framerate for joining
  Trim(1, framecount-1) #trim ends, leaving replacement frames
  
  Source.trim(0,-N) ++ last ++ Source.trim(N+X+1,0)
}


######################################################
#
# Insert missing frames
#
######################################################

function InsertFramesMC(clip Source, int N, int "X")
{
  # Insert X motion interpolated frames at N
  # N is the insertion point
  # X is the number of frames to insert
  # the frames will be interpolated with Source frames N-1 and N as references

  X = Default(X, 1)

  loop(Source, X+1, N, N)
  ReplaceFramesMC(N, X)
}

######################################################

A short example from your clip:

import("C:\Program Files (x86)\AviSynth\plugins\ReplaceFramesMC.avs") 

Mpeg2Source("Test2.d2v", CPU2="ooooxx", Info=3) 

Trim(1250,1299) # just a short section with constant motion
ShowFrameNumber(x=20, y=20)
src = last

DeleteFrame(1)
InsertFramesMC(3)
DeleteFrame(5)
ReplaceFramesMC(17)
DeleteFrame(21)
InsertFramesMC(22)
DeleteFrame(25)
InsertFramesMC(27)
DeleteFrame(29)
ReplaceFramesMC(41)
DeleteFrame(45)
InsertFramesMC(46)

StackHorizontal(src,last)

But that means you must go through the video frame by frame to locate the duplicate and missing frames. It's will take eons.

Note that the new video contains two fewer frames after 50 frames. I suspect that's because the real underlying frame rate is 24 fps.

[nbarzgar]

Some duplicate frames are simply duplicates. Those can be removed with DeleteFrame().

Other duplicates are there taking the place of a missing frame, ie instead of 1 2 3 4 5 you have 1 2 2 4 5. The second of the duplicates can replaced with motion interpolated between the surrounding frames. I created a function called ReplaceFramesMC() that does that. It was based on a function originally called RX().

In places where there are missing frames you can use InsertFramesMC() (also based on the filter originally called RX()) to create a new frame with motion interpolated between the frame before and the frame after.

(...)

But that means you must go through the video frame by frame to locate the duplicate and missing frames. It's will take eons.

Note that the new video contains two fewer frames after 50 frames. I suspect that's because the real underlying frame rate is 24 fps.

Hello @jagabo,
awesome, I thank you so much for your time and trouble!
I will review this at leisure.
BR
nbarzgar