Sign In

PaNup: or, how to upscale PAL + NTSC capture and live (quite) happy...

Author
Time
 (Edited)

Today I was thinkering with the "pyramid" LD capture, and, when I was looking for the files, I encountered an old test script for upscaling, abandoned two years ago. Idea was good, so I managed to improve it - as now I have more knowledge than at that time - and results are quite good.

The idea is simple: take two captures of the same content, one PAL, one NTSC, then merge them to "squeeze" every bit of details from it... everyone knows that a PAL capture has 576 horizontal lines, while NTSC has 480... now, when a movie was transferred to video, usually original resolution was higher than that (not all the times, but often); so, the PAL and NTSC "received" different lines of image... see the next image (obviously intentionally exagerated...):

As you can see, the red, green and blue lines have different thickness in PAL and NTSC; the aim of this technique is to combine those different lines to recreate an image closer to the original one.

To test my theory, I took some high definition images, resized each dimension to 1/3 to simulate NTSC, and to 2/5 to simulate PAL, then I wrote a script to mix and upscale the simulated PAL and NTSC images. Here you are the close-ups of the results; PAL and NTSC are the simulated images upscaled with pointresize, PALup and NTSCup are upscaled using a bicubicresize, to simulate a simple upscaler, PaNup is my script (oh, how much I love acronyms - PaNup=PAL and NTSC upscaled) - no noise reduction is used:

(you can download original, simulated PAL and NTSC, and PaNup images here - 14MB)

Of course, the validity of this tests are questionable, as the PAL and NTSC images are simulated; nevertheless, these give an idea of what could be achieved using "simple and poor" low definition media, like VHS or better laserdisc, and DVD too! Not HDTV, OK, but still quite a good result.

The problem is, in real life, it's close to impossible to find a movie which has a PAL and NTSC version that match each other 100% - usually they use different masters, so cropping and color grading are different... but, in those almost-impossilbe cases where a PAL and a NTSC laserdisc (and VHS) are virtually the same, the ideal condition is to capture the PAL at 768x576 and the NTSC at 640x480 (actual letterbox images at 2.35:1 will be 768x326 and 640x272, at 1.85 will be 768x416 and 640x346); if the capture card could capture at 720x576/480, only the Y axis will benefit - this is also the case of DVD.

Real life test could be found in this thread.

The ResolveR ultimate restoration workstation | [Fundamental Collection] thread | blog.spoRv.com | fan preservation forum: fanres.com |

Author
Time

That's an interesting concept.  Another potential pitfall is, of course, that a number of PAL LDs and DVDs use NTSC masters e.g. the SW and ESB GOUT DVDs.

Author
Time

I'm quite sure the THX PAL laserdisc don't use NTSC masters - as they often have more resolution than GOUT DVDs, but almost sure the original masters used are the same, as it seems there are the same faults...

The problem is it's almost impossible to align the PAL and NTSC perfectly... but that's "almost" is that what is interesting...

Take a look at the link I added to the first post to have an idea: the captures were not high quality, and not perfectly aligned, but result is everything but bad!

It will be interesting to find a movie which has not any HDTV version, but has PAL and NTSC versions - both laserdiscs or both DVDs - to test.

Anyone who happens to have PAL and NTSC versions of the same movie, that are perfectly spacially aligned each other, and want to share some clips (10/20 seconds long, lossless), please P.M. me as I'd like to test this script further.

The ResolveR ultimate restoration workstation | [Fundamental Collection] thread | blog.spoRv.com | fan preservation forum: fanres.com |

Author
Time

This looks interesting, Andrea, I'm impressed at how you were able to regain some details, like the numbers in the B&W test card. I think this script could prove very useful.

Do you reckon it could also be useful for VHS ?

Author
Time

It should work with VHS too, but, as it has lower resolution (especially chroma), results will be less impressive, but always better than "straight" PAL or NTSC capture... I'm working right now with another test, I'll post it soon (I hope...)

The ResolveR ultimate restoration workstation | [Fundamental Collection] thread | blog.spoRv.com | fan preservation forum: fanres.com |

Author
Time

Here you are a "fast and dirty" real source test... I found into that old HDD two files; first is the PAL GOUT, second is a 1997 SE test that msycamore posted about a year ago...

GOUT is PAL letterbox, and myscamore's test is NTSC anamorphic; the latter has (obviously) a different color grading, and different cropping too... to match a bit the colors, I ColourMatch'ed the latter to be similar to GOUT, then I added some borders to trying to align spacially the two images... as you can see, this is one of the worst cases, as there are three major problems to solve (letterbox Vs anamorphic, color grading, different cropping)

I cut a small clip (32s) because after that the SE had different scenes; playing the PaNup video shows that many scenes are visibly off alignment, while others are almost in line, in particular the last one... here you are some screen shots:

(you could note some artifacts onto the NTSC due to ColourMatch script)

I eagerly wait to test PaNup with proper material...

The ResolveR ultimate restoration workstation | [Fundamental Collection] thread | blog.spoRv.com | fan preservation forum: fanres.com |

Author
Time

I have the original Matrix in both NTSC and PAL, same colors, but slightly different cropping and different sizing. Let me know if you want some clips.

Author
Time
 (Edited)

As the BD exists, they are not nee... WAIT! As I have some problems with my "The Matrix" project, and I must replace some scenes with upscaled DVD, why not? I have the PAL DVD, all I will need some NTSC lossless scenes... I'll let you know, thanks for your offer!

The ResolveR ultimate restoration workstation | [Fundamental Collection] thread | blog.spoRv.com | fan preservation forum: fanres.com |

Author
Time
 (Edited)

I tested PaNup using "The Abyss" PAL DVD letterbox, and NTSC R6 DVD, anamorphic; overlaid at 40% PAL and 60% R6 (as it has more resolution); applied at the end a grain plate - LINK

It could be an interesting technique to restore movies that are not available in HD, but only as PAL and NTSC DVDs - or letterbox and anamorphic DVDs.

The ResolveR ultimate restoration workstation | [Fundamental Collection] thread | blog.spoRv.com | fan preservation forum: fanres.com |

Author
Time

That looks really good. I'm surprised you were able to remove the artifacts that much, especially the stray interlaced blocks.

Author
Time

Thank you very much! I'm thinking about to use this method to make "The Abyss" using both PAL non-anamorphic and NTSC R6 anamorphic DVDs; but, just to "spice up" something more, I want to try to add also the NTSC non-anamorphic DVD and see if I can squezze some details more!

The ResolveR ultimate restoration workstation | [Fundamental Collection] thread | blog.spoRv.com | fan preservation forum: fanres.com |

Author
Time

I have PAL and NTSC DVDs of a movie sourced from the same master if you need more material to test on.

Author
Time

Thanks in particular to "The Abyss" and AVP:R, I think this technique is consolidated; final results are very good, better than any single PAL or NTSC upscale.

Many thanks for the offer anyways; maybe you could help for the next technique/method - still to be discovered... (^^,)

The ResolveR ultimate restoration workstation | [Fundamental Collection] thread | blog.spoRv.com | fan preservation forum: fanres.com |

Author
Time

A good test case for this would be Farscape whose original 35mm footage was lost or destroyed and all we're left with are the NTSC and PAL copies. The Blu-Rays were made from upconverted PAL video. Could the technique described in this thread improve upon the Blu-Rays?

Author
Time

Didn't know Farscape was actually an upconversion... well, if both the PAL and NTSC video align perfectly, the PaNup technique should obtain a better result, surely in the vertical resolution.

If you can provide the same frame from PAL and NTSC DVD, and from BD to compare the PaNup result, I'll be happy to do a test!

The ResolveR ultimate restoration workstation | [Fundamental Collection] thread | blog.spoRv.com | fan preservation forum: fanres.com |

Author
Time

Here are some frames from the NTSC and PAL DVDs, and the Blu-Ray: http://imgur.com/a/nymHs

Notes:

  1. All were taken using VLC's built-in snapshot functionality for the best quality, with no deinterlacing, aspect correction, or any other video effects or postprocessing (except see #2, below). If you know of a better way, let me know.
  2. The Blu-Ray images were automatically converted by imgur from .png to .jpg. The remaining images, all .png, appear unchanged from what I uploaded, based on the file size.
  3. The PAL images show very noticeable lossy compression. I took them from the Region 2 Limited Edition DVD box set of season 1, ISBN 5030305891015, released in 2002. There's a more recent R2 DVD edition, maybe the quality is higher.
  4. The DVDs are ASIN B002GP7ZWI, released in 2009.
  5. The Blu-Rays are ASIN B00E688720, released in 2013.
  6. The NTSC DVDs show evidence of 3:2 pulldown. I chose frames without noticeable interlacing for this test.
  7. It's possible that the NTSC video was created directly from the PAL masters, in which case this experiment won't reveal any additional detail.
Author
Time
 (Edited)

traal said:


  1. All were taken using VLC's built-in snapshot functionality for the best quality, with no deinterlacing, aspect correction, or any other video effects or postprocessing (except see #2, below). If you know of a better way, let me know.

VLC scales to the Display Aspect Ratio, although in this case it appears the PAL discs are incorrectly flagged as 16:9.

An easy way to grab unscaled PNGs is opening each VOB in VirtualDubMod and hitting CTRL+1.

Author
Time

@traal: indeed PAL quality is a lot lower than NTSC... please follow drngr's tip and repost PAL images

The ResolveR ultimate restoration workstation | [Fundamental Collection] thread | blog.spoRv.com | fan preservation forum: fanres.com |

Author
Time

Made some tests, here you are the results:

http://screenshotcomparison.com/comparison/109915

they are only overlaid - no deblock, no clean, no grain... nothing!

You should look at the details with at least a 4x zoom to note better the difference between them.

By the way, why the NTSC height is 540 pixel instead 480?!?

The ResolveR ultimate restoration workstation | [Fundamental Collection] thread | blog.spoRv.com | fan preservation forum: fanres.com |

Author
Time
 (Edited)

For the same reason that the PAL width was scaled. When I suggested VDubMod images, I meant for both PAL and NTSC.

Author
Time

VirtualDubMod won't read the NTSC DVD because the DVD is encrypted, and it crashes when it tries to read the .mkv created by MakeMKV. Any ideas on how to proceed?