PAL Rip @ original resolution

[UncleBop]

Hello there!

I'm about to rip a PAL DVD, that is actually a cartoon, so it can be ripped at original resolution without any impact on quality or rip size.

That's where my problem arises. Original DVD resolution is 720x576, but pixels are not square, that's why I need to take it into account and perform resizing. As 1:1 gives me ellipse-like circles.

In GKnot Resolution tab I select
Input Resolution: PAL
Input Pixel Aspect Ratio: PAL non anamorphic (4:3)

And GK comes up with 720x528, that also doesn't give me an accurate circle, and my thought is that output resolution must be set to 720x540, that is actually 4:3. But GK won't let me choose this one. The only way to get it is to edit avs script manually, the approach I don't actually like.

So I need an advice, as I feel like I'm quite lost in all this resolution-pixel math.

[unskinnyboy]

Is your DVD 4:3 to start with? Are there no black bars to crop? When checking to see if the AR is right, have you checked the 'Resized' option?

http://www.doom9.org/images/gknot/gk-d2vview.gif

Can you post a small sample of the scene containing the circles?

[UncleBop]

Is your DVD 4:3 to start with?
Yes

Are there no black bars to crop?
Nothing to crop as it's originally digitally mastered cartoon


When checking to see if the AR is right, have you checked the 'Resized' option?

http://www.doom9.org/images/gknot/gk-d2vview.gif
Yes

Can you post a small sample of the scene containing the circles?
Here it is. If you measure the box around the moon, you can see that its width for about 10px more than height. In 720x540 case the surrounding box is a square.

http://imageweb.ws/files/1/moon.jpg

[unskinnyboy]

When I said sample, I meant a VOB sample.

[setarip_old]

@UncleBop

Hi!

Since you're dealing with animation, I'd ask - Have you checked the ORIGINAL DVD's dimensions for this very same Moon image, to see if it is truly round or, perhaps, the same dimensions as your posted screencapture?

[UncleBop]

2 unskinnyboy

I'm not sure if I can post a vob file... If you can gimme a hint how to cut a piece of vob...

2 setarip_old

I know what you mean, but I believe it must be round, as it's digital animation.

But anyway, regarding output dimensions... 720x540 is 4:3 with a square pixel... Media Player on DVD playback resizes the picture from original 720x576 to 768x576, which is also 4:3

Yeah, I know, 540 is not a multiple of 16, but anyway, where I'm wrong?

[Jeffster]

On the Options tab you may want to experiment with unchecking "Follow ITU-R BT.601 Standard" in this instance. It will bring you closer to the resolution you desire... but read carefully the caveat underneath about this option.

You won't achieve a vertical resolution of exactly 540 without using mod-4 which isn't recommended though (as I notice while typing this you're already aware of). :)

[setarip_old]

I know what you mean, but I believe it must be round, as it's digital animation.Please humor me and check to see if your assumption is correct, as stranger things have been known to happen ;>}

[UncleBop]

2 Jeffster

Thanks for the info... But if it's recommended to have this option checked, I'll stay with it :)

2 setarip_old

Cannot see the way to measure original moon, as it's anyway resized by players :)

Okay, anyway, if you look at the picture, you still say that the moon is round until you measure it. And seems that it's not making to much sence disputing about those 8-10px?

[unskinnyboy]

I was going to look at the sample and get into the murky ITU-R BT.601 territory, but since someone mentioned it anyway... :]

@UncleBop, Don't blindly go as per what's written in there, saying it's recommended to leave it checked. That's only applicable if the DVD was authored respecting ITU-R BT.601. Uncheck it to see if your moon becomes round again. If so, problem solved. If not, cut a piece of the VOB using MPEG2cut or ChopperXP and upload it to some hosting site and give the link here.

BTW, if you :search:, there's tons of info on ITU-R BT.601, for and against. Lots of confusion and fun.

[UncleBop]

Hi again.

After some more research, I noticed that picture looks pretty much ok @ 720x528, and actually I cannot choose between 528 (checked ITU-R BT.601) and 544 (unchecked ITU-R BT.601)

So I stopped @ 720x528...

I'll search and read the stuff, but the problem I noticed while searching this forum earlier is that in many cases discussion goes too deep into specifics and ends up with posts where I cannot understand nearly a single word :)