What % of DVD movies are 29.97 fps?

[johnells]

Just wondering, of the more popular studio DVD releases what ballpark percentage are encoded at 29.97 fps?

Also, how rare are 24 fps movie DVD's?

I am assuming that all the movies were shot on film and in the case of the 29.97 fps DVD's, 2:3 processed before being placed on the DVD.

John

[Trust_No_1]

All NTSC DVD's are at 29.97 fps. It is physically impossible for an NTSC DVD to be encoded at 24 fps.

A PAL DVD is the closest you will get to 24 fps, since it is 25 fps.

[Conquest10]

All NTSC DVD's are at 29.97 fps. It is physically impossible for an NTSC DVD to be encoded at 24 fps.

A PAL DVD is the closest you will get to 24 fps, since it is 25 fps.

[johnells]

Thanks for the feedback.

OK so if you shoot 24 fps progressive you must always always encode it at 29.97 interlaced? (let us limit this conversation to NTSC ... too many numbers confuse me).

Seems funny that the DVD spec did not allow for video camera work shot at 24 fps progressive. To go through the process twice, once to "pullup" to DVD and once to "pulldown" for progressive monitors, seems like a double negative.

John

[Conquest10]

don't listen to him. most dvds are 23.97 with 3:2 pulldown. the only ones i've seen that are 29.97 are wrestling and extra features on the dvd that are tv specials like the making of documentaries.

[vandakeg]

Conquest is right. Nearly ALL DVDs are 24fps... this has nothing to do with PAL or NTSC. It has to do with progressive and interlaced. DVD players use a 3:2 pulldown to get an interlaced signal from a progressive source.

[johnells]

Remember I assumed a film based transfer!

OK! So what you are saying is that most DVD's are encoded to 24 fps progressive! The non-progressive DVD players perform the interlacing and frame rate change before spitting out the signal. Unless of course you have a progressive DVD player which will spit out the original progressive signal?

Hmmmm! Now I am unsure! For sure!

I was under the impression that all DVD's were encoded at NTSC specs (interlaced) and if the 3:2 film tags were present (aka NTSC film) in the MPEG stream the DVD player would pick up on this and offer to spit out the recomposited full frame (assume you have a Progressive DVD player)? Or you can force the player to Film mode whereby it will assume all interlaced MPEG frames were generated from a progressive 24 fps source.

John

[adam]

Almost all anime is 29.97fps, the same goes for most dvds originating from television broadcasts ie: tv series. There is a very small minority of other NTSC DVDs which have been hard telecined and are encoded at 29.97fps. Out of several hundred NTSC DVDs that I have ripped, the only one that I can think of at the moment is Jay and Silent Bob.

Other than that, almost all NTSC DVDs of theatrically released movies are encoded at 24fps and have the RFF/TFF flag enabled (2:3 pulldown.)

What most people don't realize is that there are two elements that make a progressive stream. The frames themselves can be either progressive or interlaced and the entire stream can be tagged either progressive or interlaced. So pretty much all NTSC DVDs have interlaced frames, which means that each frame has physically been split into fields during encoding. This is done because if the dvd player had to do it, the quality would be much worse. But the streams are almost always tagged progressive, which means that the fields are played simultaneously instead of one after another. The result is that you see the whole frame, and for all intents and purposes it can be treated as a progressive frame.

Now when played on a non-progressive dvd player, the pulldown flag is processed and the fields are repeated in a 2:3 pattern giving you the NTSC required 29.97fps. When played on a progressive dvd player the pulldown flags are not processed and you get 24fps progressive frames. Again, the frames were encoded as interlaced, but since the stream is progressive you essentially get progressive playback.

So what % of NTSC DVDs are 29.97fps? Not counting anime and tv series its probably less than .5%.

[Trust_No_1]

This might help...

http://dvddemystified.com/dvdfaq.html#3.4

[wipeout]

is 3:2 the same as 2:3 ?

[DivXExpert]

read the glossary on the sidebar.

<<<<

ctrl+F "3:2" and "2:3"

Read

[adam]

Well after reading that section of the FAQ I must have gotten it backwards. I should have said that the frames are progressive but the stream is tagged interlaced.

[johnells]

Thanks Adam! I think I am converging to an answer here. You confirmed a lot of what I thought. The purpose of my questions is so that I can understand better the encoding software. I have an 8 cm DVD that defies decoding/re-encoding. Now that I know a bit more about the process I might be able to sort this out.

So to summarizie the topic for "most" Film Based DVD's:

1. The MPEG-2 data is encoded as 24 fps interlaced (48 fields).

2. The DVD decoder performs 2-3 pulldown (repeat first field) for display on NTSC TV's.

3. The playback is either 29.97 fps interlaced (60 fields) or 24 fps progressive depending on if your DVD player is progressive or not and it detects the "repeat first field" flag.

John

[dragpeace]

I'm also a newbie and have a question along these lines (I apologize if this is a dumb question - I've looked around and can't find an obvious answer):

If someone is at home burning DVD-Rs (or DVD+Rs) on their PC in the USA, then the result will almost certainly be progressive 24fps NTSC, correct? Am I way off on this?

Is there an easy way to tell what your source DVD is (i.e. PAL vs NTSC, progressive vs interlaced, 24fps NTSC vs 30fps NTSC, 4:3 vs 16:9)? Is there one program that will just look at the disc and tell you (I know, it can't be that easy! )?

I'm getting the hang of this stuff, but I still have a tremendous amount to learn!

Graham

[FOO]

I have been analysing the MPEG2 spec in order to write
processing programs and there are TWO important fields in the
headers . There is a Progressive Flag and there is a Picture Type
which can be Field1 Field2 or Frame.
The pulldown flags will only work when Progressive is set.
Also a frame may be stored as two fields or 1 frame .
I have never seen a video that wasn't stored as frames and Iv'e looked at
lots but I don't think it makes any difference..
Soft pulldown always has Progressive = 1 set and 29.97 video always
has Progressive = 0
I assume a real Progressive video would Have Progressive = 1 and no TFF/RFF flags, but I havent seen one.
Of course there a lots of videos that have it both ways in the same video.
I cannot figure why anyone would do that .

[ronnylov]

All PAL DVD's are encoded at 25 fps, some are interlaced but most are progressive. The 24 fps of a film is speeded up to 25 fps.

[dragpeace]

All PAL DVD's are encoded at 25 fps, some are interlaced but most are progressive.

That makes sense. I'm assuming that any DVD based on a film (whether PAL or NTSC) will be progressive, as well.

What I'm curious about is the following scenarios: A person takes a VHS tape (either NTSC or PAL), edits the video, and then authors and burns a DVD-R on their home PC. My understanding is that the original VHS video will be interlaced, whether or not it is NTSC or PAL. However, what I'm trying to understand is the output on the other side - will the created DVD be progressive or interlaced? Does the "conversion" of the interlaced VHS tape to the DVD usually result in a progressive DVD, or because the source is interlaced, does that imply that the result must also be interlaced?

I'm just trying to get my head around this whole procedure, as I'm just starting to play with video. It's fascinating stuff, but much more complex than I realized!

Graham

[FOO]

If you do the "conversion" it will be however you do it.

First you must capture it. The capture card will receive 60
fields/sec. It will then do whatever it pleases. If you capture
240 lines , it will probably just get every other field . If 480 ,
It will probably combine every pair to a frame.

Then you encode it. The encoder can operate on the whole frame.
or on each field , even if frames were captured.