First NTSC DVD, do I simply re-encode?

[N3m1515]

Hi,

I have done a lot of backups in my time, so I am experienced, but no expert.

I am about to do Hellboy (USA) and while I am sure that my player (pioneer DV 444 = progressive scan) does play NTSC I am not sure if I need to do anything in particular to the stream different from my normal method.

Mainly I am unsure about whether to 'Force Film' in DVD2AVI and also whether to use 'Pulldown' after re-encoding. I am at a loss as to whether 29.97 is preferable to 23.97 fps on PAL systems. As i said I am no expert.:D

The VOB details are thus:


Num. of picture read: 3121
Stream type: MPEG-2 MP@ML VBR
Resolution: 720*480
Aspect ratio: 16:9 Generic
Framerate: 29.97
Nom. bitrate: 9800000 Bit/Sec
VBV buffer size: 112
Constrained param. flag: No
Chroma format: 4:2:0
DCT precision: 10
Pic. structure: Frame
Field topfirst: No
DCT type: Frame
Quantscale: Nonlinear
Scan type: ZigZag
Frame type: Progressive
Notes:

For clarity my method is:
DVD2AVI
Simple AVISynth script
Re-encode with CCE
Author with Maestro

If I am to follow my normal method then that is fine, but I would be grateful if someone could assist me as I also have some issues regarding subs and their timing, do I need to do anything different(I use Subrip) and chapters, I just tried to import chapters and got I-frame inconsistency message. I am sure this is because I didn't use the FILM CCE.TXT, I used the normal one I usually do which obviously has different I-frame positions.:o

Any help would be greatlt appreciated, thanks.

[Matthew]

Well presumably this is 100 percent film? It is a movie after all.

In which case just use force film, and re-encode as 23.976. Then use pulldown.exe to get to 29.97.

The chapter and subs issues are both consistent with the m2v not having the drop frame flag - this can be added using pulldown.exe at the same time as it adds the other flags.

[N3m1515]

Thanks for the response.:) Just the simple kind of reply I like (and can manage).

It never got to 100% but did reach 99% in DVD2AVI.

But could you tell me why I would force film down to 23.97 then get it back to 29.97, is it a filesize issue.

Cheers.

[Matthew]

Movies are shot at 24 fps (that's what it's shown at in cinemas). But NTSC is 29.97 fps. So what is done is that the movie is slowed down a touch to 23.976 fps (i.e. movie actually runs longer). Then flags are inserted into the stream that tells the DVD player to replay certain fields. That is, the stream is being "padded". You may notice slight jerkiness on panning scenes and this is why.

Encoding film material at 29.97 means you would be "hardcoding" this repeat data into the video stream, which is very inefficient. It makes much more sense just to have the flags only and let the dvd player do the work.

There should some technical info about this topic in a couple of the guides/articles on this site :)