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Help Wanted: PAL/NTSC hybrid transfer query

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I’ve been toying with the idea of creating a hybrid transfer from the Star Wars DVD/HDTV stock, one that exploits the (usually) better picture of the PAL format, but maintains the correct running time and audio pitch of the NTSC format.

Let me set this up and then I will pose a query primarily aimed at NTSC users who already own 16:9 TVs. The following material is uncompressed data from the PAL and NTSC DVDs for EP3.

(1) The film transfer on the PAL DVD is stored natively as 720x576 pixels. During playback, this information is stretched horizontally to 1024x576 resolution, which gives us the following corrected image on a 16:9 display:
http://img79.imageshack.us/img79/8914/framepalxz4.png

(2) The film transfer for the NTSC DVD is stored natively as 720x480 pixels. During playback, this information is stretched horizontally to 854x480 resolution, which gives us the following corrected image on a 16:9 display:
http://img68.imageshack.us/img68/6114/framentscpx0.png

There is considerably more vertical detail in the PAL version, though this doesn’t necessarily mean that the PAL version must be perceived as better. However, it has been shown elsewhere that the NTSC DVDs suffer from more prominent edge-enhancement artifacts, and this is another reason to favor the PAL footage in your Star Wars project.

In either case, we give up a lot of vertical resolution to the black bars, which are needed to maintain the original Cinescope frame. But if we are willing to alter the frame somewhat, a new option is available for NTSC projects.

(3) Here, the NTSC frame approximates a true, 16:9 image (there is very little letterboxing) and uses ALL of the vertical detail afforded on the PAL DVD. Thus, we are trading off the Cinescope frame for more lines of information.
http://img67.imageshack.us/img67/8707/framehybridvv4.png

Here is the question: If you are in NTSC land and own a 16:9 display, would you prefer #2 or #3? That is, would you give up the original frame for PAL-like detail?

Note. Many of us can enjoy either picture on a universal player, but this doesn’t address the audio issue, which is why I am asking people to think only in terms of a DVD that is NTSC compliant with respect to size and frame rate.

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Digital Fanedits
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I would strongly advise you not to crop - keep the 'scope frame.
Originally posted by: Anti-Matter
... the PAL DVD is stored natively as 720x576 pixels. During playback, this information is stretched horizontally to 1024x576 resolution... This is only true in very specific cases - when you're viewing the DVD on a PC, using a media player in non-full-screen mode, using a basic AR calc instead of correcting for ITU-R, your desktop is set to a resolution with square pixels...
It's better to just say "the image is scaled to suit your display".
There is considerably more vertical detail in the PAL version...
Screenshots - or it didn't happen! However, it has been shown elsewhere that the NTSC DVDs suffer from more prominent edge-enhancement artifacts, and this is another reason to favor the PAL footage in your Star Wars project.
This is the case with TPM (see this R1 vs R2 comparison) but I thought AoTC and RoTS were much improved.

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" I would strongly advise you not to crop - keep the 'scope frame."

I am not committed to cropping, because I also feel it is difficult to abandon the Cinescope AR, even if the PAL version did afford a more beautiful picture.

Maybe an HD capture > NTSC DVD is the way to go.
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Digital Fanedits
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If I myself could cap LD to DVD in any format, I'd prolly aspect-correct PAL LB -> NTSC Anamorphic.

Increase in vertical res: 1.2x
Target vertical res: 352 (approx.)
NTSC Source vertical res: 272 (approx.)
PAL Source vertical res32.: 326 (approx.)
Needed vertical scaling when converting to NTSC/A: 10.43% (approx.)
Needed vertical scaling if sourcing from NTSC: 32.35% (approx.)

Even though you'd still need to resize, the scaling wouldn't be as drastic. If your source image actually *had* 326 scanlines... all the better!

"Right now the coffees are doing their final work." (Airi, Masked Rider Den-o episode 1)

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To be quite frank, if you're going to go through the trouble [read: cardinal sin] of cropping it, you might as well crop a full ~12.79%* from both sides so it will completely fill out a 16:9 screen. The screen shot above will please no one: You've violated the director's vision of the film and the black bars are still there.

*I'm not sure how many pixels that translates into.
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if you're going to go through the trouble [read: cardinal sin] of cropping it, you might as well crop a full ~12.79%* from both sides so it will completely fill out a 16:9 screen.

At which point you begin interpolating the original PAL footage that you were trying to exploit on an NTSC DVD.

"the black bars are still there"
How many of those lines would appear on your 16:9 TV ? I'm not sure that specific point is the deal breaker for 'everyone' (since you are speaking for all of us).

I'm confused. You suggest further cropping but would not give up the original framing anyway. Aren't you simply saying that you would prefer the (original) 364 lines in case #2?

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Digital Fanedits
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(1) The film transfer on the PAL DVD is stored natively as 720x576 pixels. During playback, this information is stretched horizontally to 1024x576 resolution, which gives us the following corrected image on a 16:9 display:

(2) The film transfer for the NTSC DVD is stored natively as 720x480 pixels. During playback, this information is stretched horizontally to 854x480 resolution, which gives us the following corrected image on a 16:9 display:


It's not that simple - for a correct AR (if I remember correctly), a PAL 720x576 image should first be cropped to 702 pixels, and THEN stretched to a 16x9 frame (best not to talk about pixels at this point). An NTSC image should first be cropped to 704 pixels, then stretched to a 16x9 frame.

In short, if your final MPEG has 8 (or 9 for PAL) pixels of black on either side, these should never be visible on any display.

DE
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Originally posted by: Anti-Matter
At which point you begin interpolating the original PAL footage that you were trying to exploit on an NTSC DVD.

"the black bars are still there"
How many of those lines would appear on your 16:9 TV ? I'm not sure that specific point is the deal breaker for 'everyone' (since you are speaking for all of us).

I'm confused. You suggest further cropping but would not give up the original framing anyway. Aren't you simply saying that you would prefer the (original) 364 lines in case #2?



What I meant was, if it was up to me, I wouldn't crop it at all, but if you're going to, you'll appease more people by making it fill the entire screen. Otherwise, it's just a pointless zoom.
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a PAL 720x576 image should first be cropped to 702 pixels...
An NTSC image should first be cropped to 704 pixels

...or you could just let your player and TV manage the active content area for you

I've never heard of anyone resizing a DVD that is already encoded to spec down to 704.
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Digital Fanedits
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I see now that people are either confused, distracted or they are missing the question.

First, case #3 is not an example of zooming. It is the PAL image that has been cropped to fit within an NTSC frame. If we zoom the original NTSC image, we are not going to end up with a better picture.

Second, the reason people generally prefer a PAL DVD image over an NTSC DVD image is similar (both technically and conceptually) to why any of us would prefer a music track sampled at 44.1kHZ over one sampled at 22kHZ: it is called resolution.

The PAL (#1) and NTSC (#2) screenshots are depicting the SAME objects, but with DIFFERENT resolutions. The PAL DVD image always has the potential to deliver a more vivid picture because it always has ~434 lines (in the Cinescope case) to depict a visual event, whereas the NTSC DVD image must depict the same event using only 364 lines.

If you cannot see this in these particular examples, just ignore them. It's not terribly important, and I could have just used black on white cards to illustrate the same point.

The question I posed merely asks NTSC users whether maximizing detail on a 16:9 display is more important than preserving a Cinescope frame. You cannot have both.
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Digital Fanedits
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Well, since you put it that way...

Detail. You can't go wrong with detail.
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I'm not an 'NTSC user', but I would always rather have the scope frame (providing this is the intended ratio), a scope film will almost always look better that way, you lose too much by cropping of the sides.

If your this bothered about detail just get an HDTV, and download wookiegroomer's WMV files, that way you get the highest possible detail and the correct ratio.