FORUMS: list search recent posts

24p in an NTSC DVD

COW Forums : Adobe Encore DVD

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
clyde villegas
24p in an NTSC DVD
on Jun 8, 2010 at 9:33:31 am

I was told in another forum that regular movie DVDs purchased/rented in stores are actually 24p.

Now that I have 24p footages (with the pull down removed, making them real 24p footages), is it ok to create DVDs with 24fps frame rate? How is this achieved in Encore?

If I put back the pull down before importing the 24p footages in Encore, does that mean I have to create the DVD in 29.97?

We're in the Philippines so I'll use NTSC. Thanks!

ut in omnibus glorificetur Deus


Return to posts index


cowcowcowcowcow
Jeff Bellune
Re: 24p in an NTSC DVD
on Jun 8, 2010 at 11:31:56 am

Hi Clyde,

Try this:



-Jeff

The Focal Easy Guide to Adobe Encore DVD 2.0


Return to posts index

clyde villegas
Re: 24p in an NTSC DVD
on Jun 9, 2010 at 12:33:35 am

Thanks Jeff! Is this the export settings of Premiere or Encore? It looks like Premiere.

ut in omnibus glorificetur Deus


Return to posts index


Jeff Bellune
Re: 24p in an NTSC DVD
on Jun 9, 2010 at 12:50:51 am

Nope. It's Encore (notice the Library menu that's showing in the Preview panel).

-Jeff

The Focal Easy Guide to Adobe Encore DVD 2.0


Return to posts index

clyde villegas
Re: 24p in an NTSC DVD
on Jun 9, 2010 at 1:28:22 am

I see. About the GOP Settings where M frames are at 3 and N Frames are at 12, what do those numbers mean? Will I always use 3 and 12 whenever I make a DVD for both 29.97 and 23.976 or is it for 23.976 only?

ut in omnibus glorificetur Deus


Return to posts index


cowcowcowcowcow
Jeff Bellune
Re: 24p in an NTSC DVD
on Jun 9, 2010 at 1:32:10 am

It's for 23.976 in NTSC-land, and it's also usable for PAL video. Normally for 29.97 fps video the settings are 3 and 15. What that does is put a new I-frame every half second, which usually works well for MPEG2 DVD video. (15 is half of 30 and 12 is half of 24.)

-Jeff

The Focal Easy Guide to Adobe Encore DVD 2.0


Return to posts index


clyde villegas
Re: 24p in an NTSC DVD
on Jun 9, 2010 at 1:36:59 am

Thank you very very much Jeff! That's a tremendous help. I'll work on the video again tonight. God bless.

ut in omnibus glorificetur Deus


Return to posts index

dave divehall
Re: 24p in an NTSC DVD
on Jun 16, 2010 at 11:08:09 am

Hi, just curious - how would i do this with Encore CS3?


Return to posts index

dave divehall
Re: 24p in an NTSC DVD
on Jun 23, 2010 at 7:00:05 am

???


Return to posts index


clyde villegas
Re: 24p in an NTSC DVD
on Jul 19, 2010 at 11:00:50 pm

Using Premiere, I removed the pulldown and exported them as uncompressed windows files to After Effect. In AE, I used a 23.976 composition setting and color graded the videos there. I then exported them using the Lossless preset (with the audio enabled).

Now here's the problem: when I transcoded the videos in Encore, the audio layer is longer than the video. What should I do? Am I missing something. Thanks!

ut in omnibus glorificetur Deus


Return to posts index

Raja Ashok
Re: 24p in an NTSC DVD
on Jun 8, 2010 at 11:56:39 am

DVDs are capable of storing the native 24p (actually 23.976 not 24 fps)stream. With NTSC equipment, it's not possible to display 24p signal directly as the monitors only support the 60i framerate. Hence, pulldown must be added to the 24p(23.976fps) material to be displayed.
On each DVD encoded at 23.976, a flag is inserted within the Mpeg-2 data stream that instructs the player to repeat certain fields to reconstruct the 29.97 NTSC video. It's the player which will add pulldown for display on interlaced sets. If it's a progressive scan player displaying a progressive TV, it will only show the 24 frames.
In Encore, you can import a 24p footages or any pre-generated 24p mpeg files and author 24P DVDs.


Return to posts index

clyde villegas
Re: 24p in an NTSC DVD
on Jun 9, 2010 at 1:39:40 am

Thank you Raja. That's very informative. God bless!

ut in omnibus glorificetur Deus


Return to posts index


eric pautsch
Re: 24p in an NTSC DVD
on Jun 9, 2010 at 4:25:57 am

Here's a thread which explains the details of the technology. MPEG 2 does not support 23.98 framrates. The codec was around much sooner than progressive video. DVD only supports 29.97 and 25. 23.98 with the flags sets makes it a 29.97 stream.

http://forums.creativecow.net/thread/155/870715#870887



Return to posts index

Jeff Bellune
Re: 24p in an NTSC DVD
on Jun 9, 2010 at 1:48:22 pm

Hi Eric,

I can encode a 23.976 fps video to MPEG2, and get a 23.976 MPEG2 video file. When you say MPEG2 doesn't support 23.976 fps video, are you saying it's unsupported natively? That is, the 23.976 fps video only exists as a soft- or hard-telecined 29.97 fps stream? If so, I agree because I believe that's technically accurate.

However, Hollywood soft-telecines their films for DVD, effectively putting that 23.976 fps video in a "virtual" 29.97 fps stream. The extra frames that are needed for 29.97 fps display don't exist in the stored video file; only flags exist to tell the decoder what frames to duplicate. To my eye, there is a visible difference between a 23.976 fps video that's been hard-telecined vs. one that's been soft-telecined.

If your MPEG2 encoder can soft-telecine your 23.976 fps video, then that video can be put on DVD the same way that Hollywood films are, ostensibly increasing the film-like viewing experience of your video.

At least that's my understanding. If you have different information, then I'd like to hear it because I really, really don't want to be wrong about this.

-Jeff



The Focal Easy Guide to Adobe Encore DVD 2.0


Return to posts index

eric pautsch
Re: 24p in an NTSC DVD
on Jun 9, 2010 at 4:05:39 pm

Yeah...its a 23.98 file but with the 3:2 flags set making it 29.97 - the only legal frame rate for DVD MPEG 2. Its a virtual stream like you said. I think its important to know that DVD doesn't technically support true 24frames rates, Only 29.97



Return to posts index


Jeff Bellune
Re: 24p in an NTSC DVD
on Jun 9, 2010 at 4:11:34 pm

[eric pautsch] ". I think its important to know that DVD doesn't technically support true 24frames rates, Only 29.97"

Agreed.

-Jeff

The Focal Easy Guide to Adobe Encore DVD 2.0


Return to posts index

clyde villegas
Re: 24p in an NTSC DVD
on Jun 16, 2010 at 12:55:21 am

How do I include a real 29.97 video clip in this project? Encore might also put flags in it if I just drop it in the timeline.

ut in omnibus glorificetur Deus


Return to posts index

clyde villegas
Re: 24p in an NTSC DVD
on Jun 23, 2010 at 6:57:46 am

Are those flags? When I tried to do the settings the size on the disc increased by almost 1 gig. So I'm wondering if Encore is actually adding some frames.

ut in omnibus glorificetur Deus


Return to posts index

clyde villegas
Re: 24p in an NTSC DVD
on Jun 23, 2010 at 7:14:03 am

I also noticed that when I dropped in the 24p footages (from the DVX camera) on a 29.97 timeline in Premiere and then sent to Encore as 29.97, the final DVD runs smoother, much like real movies on DVDs.

I am guessing that by dropping the DVX's 24p footages (which are actually 29.97) in the 29.97 timeline, the pull-down is not removed, providing smoothness to the video. And since there has been no change in the original video (since the pulldown is intact), then video will not speed up nor down, maintaining the original speed and length.

What do you guys think?

ut in omnibus glorificetur Deus


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]