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Removing 3-2 pulldown flags from NTSC DVD?

That One Guy

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First things first - I'm used to working with PAL discs, hence I may be a bit more confused than some as to certain aspects of preparing source material  from NTSC media. I've done some searching and reading through the sticky posts - but while they are all very informative, I don't think they cover the specific issue I'm dealing with i.e. preparing source files from an NTSC DVD.

As part of a project, I have ripped my source media. I have an m2v file for video, but I'm a bit perplexed when examining it. When I load it in MediaInfo, I am told (correctly) that the file has 29.97 frame rate and (incorrectly) that it is 2 h 30 min long. When I load it in GSpot Video Analyser, I am told (correctly) that the file has a 29.97 frame rate with 3:2 pulldown flags and interlaced videostream, and (correctly) that it is 1h 23 min long.

So my first issue is - why is MediaInfo reporting an incorrect duration of the file? And why is it not detecting the pulldown flags and interlaced stream if they are present? Neither tool tells me the field mode of the video stream - how do I deal with this?

From examining the file in VirtualDub I have assumed that pulldown flags are present - combing artifacts are present in scenes with any significant motion. I have tried three different methods for removing the pulldown:
1) Open the m2v file in VirtualDub. Assign the correct colour profile, select Lagarith as the compression, then apply the IVTC filter with Field Assembly Mode set to "reduce frame rate" and Field Mode set to "Autodetect" or "Top Field First". Export to AVI.
2) Open the m2v file in DGPulldown. Select "Custom" and specify "23.976" as both input and output framerates. Select "Top Field First", "Set Timecodes" and "Set drop frames". Export a new m2v, then use that to create a Lagarith AVI in VirtualDub.
3) Open the m2v file in DGIndex. Select Video > Field Operation > Ignore Pulldown or Forced Film, then process the file.

Using the second method (i.e. DGPulldown) to remove the pulldown flags appears to create a better-looking source file than using either of the other methods. The output of method 3 still has a 29.97fps according to MediaInfo and GSpot. The output of method 1 has a correct framerate of 23.976 but shows some minor artifacts compared to the file created by method 2.

My second issue is - what is causing the difference in results - is this down to some aspect of how the IVTC filter in VirtualDub processes the input? If so, is the second method the way to go for preparing this kind of source file? Or is there a different method I should be following?
 

baileym43

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That One Guy said:
Captain Khajiit said:
Follow the method outlined in the FAQ of my HCenc guide.

That looks like exactly what I needed - thanks!
everything in Cap Khajiit's works perfectly.
i used his steps, copy/pasted his code, went back and forth a bit messaging Cap'n and it did the trick for me.
you will not be disappointed.
 
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