PAL to NTSC runtime

[jonas more]

When converting a DVD from PAL to NTSC using this or a similar method http://www.eggshellskull.com/pal2ntsc/ is the resulting NTSC runtime the same as the PAL source?

Anthony

[filmboss80]

No difference in runtime. During the conversion, some PAL frames will be merged to create additional NTSC frames, going from 25 to 29.97 per second. However, the player will identify the source, whether it's PAL or NTSC, and play back at the appropriate frame rate, so that 1 second stays 1 second, whether there are 25 frames in that second, or 29.97 frames.

[jonas more]

Thank you for your response.

I was having a debate with someone on another board and I couldn't convince him that the runtimes are the same.

Thanks again
Anthony

[manono]

Well, they're not the same if you use the default setting for DGPulldown. The guide writer (and as far as I'm concerned it's a lousy guide) conveniently forgot to mention that you need to tick the "25->29.97" box. Only if you apply that setting and then run the pulldown will both the video and audio lengths be the same. At the default setting the video comes out 4% longer and the audio after authoring won't be in synch. I think you lost the debate.

During the conversion, some PAL frames will be merged to create additional NTSC frames, going from 25 to 29.97 per second. However, the player will identify the source, whether it's PAL or NTSC, and play back at the appropriate frame rate, so that 1 second stays 1 second, whether there are 25 frames in that second, or 29.97 frames.

Either I'm misunderstanding you or that's incorrect. He's encoding at the original 25fps. No additional frames are created. Even the pulldown step doesn't create any extra frames. It sets flags in the video stream that tell the player to output duplicate fields (not frames) to go from the encoded and stored progressive 25fps to the required interlaced 29.97fps output (really 59.94 fields per second).

[jonas more]

At the default setting the video comes out 4% longer and the audio after authoring won't be in synch. I think you lost the debate.

I actually forgot about the flaw in the guide when I referred to it here.

During the 'debate' he was given the correct settings. My only error was in my original post here

As I told him, I have used this method (DGMPGDec, Avisynth with various filters, CCE-SP2, and DGPulldown) many, many times and never had a problem with a/v sync issues.

Anthony

[manono]

I actually forgot about the flaw in the guide when I referred to it here.

Oh, OK. Then I guess he doesn't know about DGPulldown's capabilities, and hasn't heard of any other kind of pulldown besides the standard 3:2 pulldown.

Then I hope you aren't following that guide literally with some of its other recommendations, such as applying deinterlacers haphazardly.

[jonas more]

Then I hope you aren't following that guide literally with some of its other recommendations, such as applying deinterlacers haphazardly.

At first I did but I have learned a lot from your other posts on the subject.

If you haven't written a detailed guide on converting PAL to NTSC, you should truly consider doing so.

You, John "FulciLives" Coleman, and many others have posted a wealth of helpful information on the subject but it would be great to have an accurate detailed guide to turn to.

Anthony

[manono]

Hehe, sounds like you already have it wired and don't need any guide at all any more.