IVTC on NTSC capture of PAL video?

[StrobeLightEpileptic]

How would a person go about doing an ivtc on something like this?

A 24 fps film undergoes a PAL speedup for a PAL video. Then someone take the PAL video and converts it to NTSC? They don't convert it ***back*** to ntsc, they just like capture it as ntsc while it's playing in a universal player.

So, even though it's NTSC it still has the sped up audio and a 4% shorter film length. And I assume it has a pulldown.

How do you take it back to it's original film elements?

[manono]

How would a person go about doing an ivtc on something like this?

No way to tell without a short sample. 10 seconds with steady movement untouched from the source will be plenty. I hope you know your away around AviSynth because using it is probably the only way to fix it.

[StrobeLightEpileptic]

Well, I've used Avisynth with the help of you and others on this board. I'm always up to a challenge when I have the time. But this is just idle curiosity on my part.

I have access to the Hong Kong laserdisc of Song of the South and from what I have read, this is what was done to create the laserdisc.

It's poor video either way, but I'm real curious as to whether it can be taken back to the original film footage.

I'll try to get 10 seconds of footage from it up in the next couple of days. This would be full frame AVI from the laserdisc.

Would it be best to have animation or live action?

[smrpix]

Live action. Cartoons often repeat frames to save the animators time and money. A "mixed" scene in this instance may be alright.

[jman98]

Hong Kong laserdiscs were in NTSC format only. So I would be very surprised if they used a PAL source for this as the Japanese laserdisc is most certainly from a proper film source. I have a copy. I have never seen the Hong Kong LD so I can't offer a definitive comment on it, but it would be rather unusual for it to be sourced from PAL video as Disney just isn't that slipshod. I can tell you that you have never lived until you've heard Uncle Remus speak Japanese (the Japanese LD has English and Japanese audio tracks - it also has hardcoded Japanese subs for the songs). Hearing Uncle Remus in Cantonese might be equally interesting.

[Brad]

The film has been released on video in its entirety in various European, Latin American, and Asian countries—in the UK it was released on PAL VHS tape in 1982 and again in 1991, and in Japan (where under Japanese copyright law it is in the public domain) it appeared on NTSC VHS, BETA and laserdisc with subtitles, while a NTSC laserdisc was bootlegged in Hong Kong from the UK PAL videotape. Despite the Hong Kong laserdisc being NTSC, it has a 4% faster running time due to its PAL source, and thus also suffers from "frame ghosting".

http://atlas.kennesaw.edu/~dhirschl/song_of_the_south/

You might be wondering, why not just use the HK LD source? Well, the HK LD has its own set of problems. It seems to be an NTSC conversion of a PAL source. Only it was not done in the typical way of using the 3:2 pulldown pattern on a progressive source. Instead, it took a PAL 25 FPS source, and converted it to 29.97 FPS (NTSC) by way of blending. Amazingly, I was able to undo some of the damage thanks to some clever scripting in AviSynth, but I cannot get it perfect. Strangely, the odd field makes a perfect conversion, so if I were making a VCD, I could do a nice one. But the even field is plagued with blending frames. I fixed some of it, but I cannot fix all of it. It's wierd.

And ironically, if you read further down, the UK broadcasts are the reverse: NTSC->PAL.

[jman98]

Your source is a former member here. Haven't seen him post here in a long time though.

I don't know why he was hellbound on using the HK LD unless he just could not live with the hardcoded subs. The picture on the Japanese one is fine except for that. I've never heard of "bootleg" laserdiscs though and can't imagine that being practical, but again, I have never seen the HK LD in question.

[manono]

Then someone take the PAL video and converts it to NTSC? They don't convert it ***back*** to ntsc, they just like capture it as ntsc while it's playing in a universal player.

So, even though it's NTSC it still has the sped up audio and a 4% shorter film length. And I assume it has a pulldown.

If the quotation from the page to which vaporeon800 linked is correct, then your description of what happened to it is incorrect. If only it really were 'like capture it as ntsc while it's playing in a universal player'. Apparently this thing is field-blended.

Which is a good reason why one always needs a sample in order to diagnose a problem as a description might not be enough, might be misleading, or might be totally wrong.

[StrobeLightEpileptic]

I plan on uploading a segment tomorrow, driver's license renewal tomorrow. So after that.

The description of this disc being bootlegged is, I think, a misnomer. In both China and Japan this film is in the public domain. So what they did was legal. I think the Japanese LD was not really a Disney release either. I own a copy of that and I notice it does NOT have the Buena Vista distribution screen, (the blue screen), that the PAL video has. If it were an official Disney release I can't see why they would have removed that.

[manono]

Here's a version I have. My notes only say it was converted from NTSC to PAL for a BBC broadcast (by field-blending, I presume). I converted it back. I see some things I'd do differently were I working on it today, but is yours better than this? (50MB):

http://www.mediafire.com/download/7zvba3uqzz9k7sz/SotS.vob

[sanlyn]

I don't know what "I converted it back" means. You mean PAL back to NTSC? It runs at 29.972, but IVTC will give 23.976 to the main figure moving, but animated objects look field-blended. That makes me uncertain: is this sample from the original DVD or is it the result of processing?

I'd have to leave that to the experts around here who can figure out these frame structure convolutions better than I can (I'll get the hang of it one of these days). But the image is cropped at 1:32:1. The original film was 1.37:1, so to preserve that theatrical release AR the image would be slightly letterboxed in a 4:3 frame. The color is not broadcast standard: it's PC601.

That the movie is banned from DVD production in the U.S. is ridiculous. The movie itself and the literature on which it is based are American classics and international treasures. Absurd.

[jman98]

That the movie is banned from DVD production in the U.S. is ridiculous. The movie itself and the literature on which it is based are American classics and international treasures. Absurd.

Not to digress, but for years there have been people within Disney who have pushed for a US release, but when CEO Bob Iger watched the film last year as a final step before approving that, he felt very uncomfortable and refused to approve it. So it's basically not out because the CEO is scared to release it. He'll leave it for the next CEO to decide what to do.

The film has gotten criticism for it's "happy" depiction of what some believe to be slavery, but in fact the movie is actually set in the post Civil War. This is why a lot of white people feel uncomfortable and why Iger is scared to release it - they are afraid of getting crucified for a positive depiction of slavery. For the record, the NAACP has no official position on the film and it's not being kept out of circulation because black people want that.

[sanlyn]

Yes, I know. Problem is, the masses are a bit on the dumb side nowadays, maybe worse than they used to be now that cable TV has trained them down even more since the 1940's, and the CEO knows it. So I can tolerate the policy, but I don't like it or agree with it. If you want to see some antiquated racial b.s. try watching or listening to Show Boat, which can be purchased anywhere. Then take stuff like Charlie Chan and Amos 'n Andy (and that old caucasian radio version really sucks, besides being racially screwy) and it gets laughable.

Anyway, I ran the vid with IVTC and sRestore and a deblender, and still ended up confused. At 23.976 the main figure moves OK, but the butterflies and whatnot look blended now and then. Don't know how one could decipher the animated part. Maybe just IVTC and live with it. But you'd still have to restore pulldown for standard disc and no telling what those blended objects would look like.

I'd be more upset than about the distorted AR and the haywire color/levels than about the political nonsense.

[dphirschler]

FWIW, I am still a member here. And I do frequently read threads, but haven't posted in quite some time.

I don't know why he was hellbound on using the HK LD unless he just could not live with the hardcoded subs. The picture on the Japanese one is fine except for that. I've never heard of "bootleg" laserdiscs though and can't imagine that being practical, but again, I have never seen the HK LD in question.

It's not just the hardcoded subs that bother me, it's the lack of good color balance and levels. I posted screencaps to illustrate the point (look at Aug. 12, 2009). I boosted the colors as much as I could and still have it look somewhat decent, but it still can't match the quality of the PAL VHS or HK LD.


Darryl

[sanlyn]

We realize you're working hard at this, but if the levels and color in the sample video are what you've managed to attain,you should be aware that they are PC levels, not video-disc/tv levels. It is beyond the RGB 16-240 range, and non-animated scenes or the extremely dark opening shot with badly crushed colors is not proper color work -- not even for PC display. If it doesn't seem "correct" to you, it's because it isn't, and AFAIK is not what the creator intended.

In order to work toward the color you want or that anyone could consider accurate and convincing for video display, either for a computer/web or for TV, you need to know something about color theory and the use of proper tools like histograms, etc. As it is, color in the opening shot is so badly crushed that it can't be repaired.

On the other hand, if what you have approximates what you want, don't worry about it.

If there's something around that you posted in August 2009, why not give us a link for it instead of assuming we would spend 20 minutes looking for a long-gone post (as I did) that doesn't exist .

[manono]

I don't know what "I converted it back" means.

I took the fireld-blended PAL source and unblended it back to progressive 23.976fps, as well as making a whole host of other changes/fixes/improvements. While there are some blends left, it's nothing serious and nothing out of the ordinary for an unblender. The fact that it's a mix of live action and animation might have made the unblender's job more difficult (?), and I expect the live action parts to be better. Unfortunately, the frame interpolators weren't available then so I couldn't use them to get rid of the damaged frames.

...is this sample from the original DVD or is it the result of processing?

I took a source someone graciously provided to me and did the best I could with it, using the knowledge and tools I had several years ago.

But the image is cropped at 1:32:1.

I used ITU resizing so I get 1.35:1. In the article to which vaporeon linked earlier, the author mentions a BBC DVD source he acquired and that it was cropped from the right side. That might explain it being narrower than it should. I haven't gone to look for the same frames he used for his comparison so have no way to know if mine is from the exact same source. He does mention that the visual quality of that BBC source is better than the rest.

The color is not broadcast standard: it's PC601.

I purposely kept scattered pixels beyond 16-235 (nothing wrong with that). Were I to do it today I might rein it in a bit more, or maybe not.

[manono]

We realize you're working hard at this, but if the levels and color in the sample video are what you've managed to attain,you should be aware that they are PC levels, not video-disc/tv levels. It is beyond the RGB 16-240 range,

That's my work, not dphirschler's (who I just learned wrote that article). I see no chroma beyond 16-240, and, as mentioned earlier, it's OK to have 'stray' pixels. It happens in virtually every commercially available DVD. The first part takes place in a very dark room at night time, lit only by a not-very-bright fireplace off to the side. While it may look quite dark on a computer monitor, it looks as it should on a TV set, which is what it's made for. It does look, though, like I tried to clip the blacks to 16. Maybe I didn't realize then that some filter or other I used clipped by default.

And that room at the beginning is supposed to be very very dark, I think, to provide contrast for the very colorful song into which it leads.

[dphirschler]

1) Of course I am aware of PC/TV levels. 2) I do know something about color theory. 3) I do know the proper use of things like histograms. 4) I didn't post a sample video. 5) The darks are crushed through out the movie (Japanese LD), not just the beginning. And I am aware that it cannot be repaired.

The Aug.2009 post was made on my own website. Sorry I wasn't clear about that. Here is a comparison shot (one of four that I referenced in my above comment). Japanese LD is on the left, PAL VHS is on the right.

No amount of tweaking can make the levels on the LD look as good as the VHS. The colors are so faint that it almost looks grayscale at times. The luma levels are crushed so badly that the dark info is just lost. And the mid levels are muddy too.

But I don't intend to hijack this thread which is about NTSC/PAL conversion. I was only answering jman98's question.

If I can find it when I get home, I will post some AviSynth scripts I made which helped. I made a script once that reversed the improper PAL conversion perfectly on a Road Runner/Coyote cartoon. Why it was PAL in the first place baffles me.

[jagabo]

The darks are crushed through out the movie (Japanese LD)

Is this an NTSC setup problem? Japanese laserdiscs will not have 7.5 IRE setup on the composite output. That causes the black levels to be too dark on North American TVs.

[dphirschler]

Oops. Posted in the wrong thread. Sorry. Moderator, please delete this.

Darryl

[sanlyn]

You can delete it yourself. Go to the postb and click the "Edit" button. In the Reply window Click "Go advanced". Then below the Reply window click "Upload files/Manage attachment". In the upload dialog window that pops up, look at the bottom, find the file you attached, and click "Remove". Then go to the reply window and delete the text of your post. Replace the text with something like "Wrong thread". Then post the reply.

[StrobeLightEpileptic]

Hi Folks. Sorry about the delay. Unexpected things. A terrific backache right now has me bedridden. Hard to concentrate.

Anyway, here is the clip I promised:

http://temp-share.com/show/gFHckRx3Y

I chose a portion where there was a lot of foreground motion, hopefully that will help you in your analysis.

Thanks.

[jagabo]

How would a person go about doing an ivtc on something like this?

http://temp-share.com/show/gFHckRx3Y

AviSource("D:\Downloads\1.avi") 
QTGMC(preset="very fast")
SRestore()
AssumeFPS(24000,1001)

Then slow the audio to match.