23.976 to 29.97

[timmyp]

Hello again,

I have read several posts and what-not about this issue and am still confused (most threads seem to deal with PAL to NTSC conversions).

What I want to try and do is convert a 23.976 movie to 29.97 so it is compatible to go on a DVD-R together with another 29.97 movie.

I understand that I could encode at 23.976 and let the DVD player do the conversion, but I want to hardcode (is that the right term?) the movie to 29.97.

I am using TMPGEnc and just need to know the settings that I shuld use to accomplish this. I'm working from VOB's that I have ran through DVD2AVI and have a .d2v and .wav file.

Thanks again,

Tim

[FOO]

I don't get it. If you already have VOBs why don't
you just use those. ?

[timmyp]

Because the VOB's are at a framerate of 23.976 and I would like to convert to 29.97.

The purpose here is so that I can place 2 movies onto one DVDR (these are the kids movies that I am making backups of... placing 2 to a disc). I can't have 2 different framerates with DVD-lab, which I'm using to author.

Thanks again,

Tim

[adam]

I find it hard to believe that DVD-Lab wont let you have a 29.97fps source and a 23.976fps (29.97fps) internal source on one DVD. Did you run pulldown on the 23.976fps source? If not then your file is not compliant. There is absolutely no reason why you should not be able to mix NTSCfilm and NTSC material on one disk.

If you did want to make the files the same, you would be MUCH better off doing an IVTC (inverse telecine) on that 29.97fps source to make it 23.976fps instead. 29.97fps is an incredibly inefficient way to encode NTSC for so many reasons. If you absolutely must do this, then just load your 23.97fps source into TMPGenc and set the output fps to 29.97fps. Then on the advanced tab enable the 3:2 pulldown filter. Again, I STRONGLY recommend you don't do this. It can degrade quality quite substantially.

[Skynet107]

I agree with adam, no need to convert anything. DVD-Lab will convert a 23.976 non pulldown file to pulldown on import. You can have the pulldown converted file along with the 29.97 movie file on the same DVD, I have done this myself with no problems.

It took me awhile to understand this, but a 23.976 NTSC video is compliant because the PLAYER has a bit flag specifically for this type of video, when it sees the bit flag it sets the player to a different mode which converts the file to NTSC timing in hardware. This was done because of the frame rate of film (24 fps) differs from NTSC so instead of converting the frame rate in the encoding process the player sets the syncs in hardware and it gives a much better result.

On another note, TMPGEnc is lousy at dealing with 23.976 files. It seems to encode them to 29.97 no matter what options you use (I don't mean it puts in the pulldown flag, I mean it seems to encode the file at 29.97 no matter what) I have not been able to get a smooth encode with TMPGEnc using 23.976 video as the source, the motion is not smooth especially in pans. CCE does not have this problem. Maybe I don't know what I am doing...

[timmyp]

OK. I see now that I was interpreting the warning in DVD-lab incorrectly (a window pops up when I add the two different sources).

The main reason I was trying to convert in TMPGEnc was to bring the bitrate down. What I found was exactly what you said... TMPGEnc gave jerky video seemingly no matter what I tried.

Solution I'm trying at this point is to use full bitrate VOB's in DVD-lab (I understand now that DVD-lab does this pulldown conversion upon adding the 23.976 VOB's so it shows in my Video & Audio asets as 29.97 FPS) and shrink the final result with DVD Shrink to fit one DVDR.

Thanks for all the info and advice... I'm learning more all the time.

Tim

[FOO]

How do you know the VOBs are 23.976 ? what said so ?

[timmyp]

Well, I kept getting jerky video when I ran this particular movie through TMPGEnc, so I opened one of the VOB's in ReStream (a tool I found on this site) and it indicated that the FPS were 23.976. So I made the assumption that that was my problem and started looking for answers/solutions to the jerky video.

Thanks,

Tim