Problems w/ AR and resizing in gknot

[grahf]

Trying to encode Tron ntsc here and have a few questions. Having some trouble on the resize, as gknot seems to give conflicting info on the suggested resize size.

The vobs are non-anamorphic 16:9 progressive 720x480, so I'm pretty sure I need to select 4:3 in input AR. Ok, fine. I crop all the black bars, and a few off the side, and I get a cropped resolution of: 712x288 which is equal to an AR of 2.472, though in the aspect ratio box Gknot says 2.253??

Now to resize, I want a 640x xxx or lower resolution because I'm aiming for a 1cd rip. Gknot suggests 640x288 which is a ratio of 2.222 which is way more than the 1% it claims to be off (seems to be basing this on the incorrect 2.253 AR ratio it reported above). By my own calculations a far more correct resize would be 640x256, equal to a 2.5 AR. Sure, I can do these manual calculations to resize, but gknot makes me doubt myself: how can it be so wrong? What is the correct resize resolution for my movie?

Finally, what are the safe limits for w-modul and h-modul? Do I really need to use 16 and 16 as gknot suggests? Thanks for any help.

[manono]

Hi-

The vobs are non-anamorphic 16:9 progressive 720x480, so I'm pretty sure I need to select 4:3

Interesting deduction you made there. If it said 16:9 in DVD2AVI, then you choose 16:9 in GKnot also. And 16:9 is by definition Anamorphic. Why did you think it was non-anamorphic? Because the vobs still had black bars? That's common for 2.35:1 movies. Read this for more information (and the other pages of the tutorial-I just chose the page that is directly related to your problem):

Anamorphic and 2.35:1 movies (http://www.thedigitalbits.com/articles/anamorphic/anamorphic235demo.html)

However, there are 2 versions of Tron out. The 20th Anniversary Edition is 16:9 widescreen anamorphic, while the original is 4:3 widescreen letterboxed. I don't know which you have.

Your other resizing problems may stem from the original mistake you made. However, Amazon.com (http://www.amazon.com/exec/obidos/tg/stores/detail/-/dvd/B00005OCMR/tech-info/ref=pm_dp_ln_d_2/104-3894764-5919151) says it's 2.20:1. But cropping and resizing to preserve AR may change that somewhat. Trust GKnot. It doesn't make mistakes. If your Aspect Error is too high, then crop some more.

Do I really need to use 16 and 16 as gknot suggests?

Read This (http://forum.doom9.org/showthread.php?s=&threadid=42708).

[grahf]

Thanks for the reply. I'm beginning to understand, I think.

Actually dvd2avi says 4:3 with this vob. Which is very confusing :confused: I guess I have the 4:3 letterboxed then?

[manono]

Hi-

Yes, if DVD2AVI says 4:3, then you have the original version of the DVD, and that's what you should put in GKnot. So, if you originally said non-anamorphic 16:9 progressive 720x480, thinking 16:9 meant widescreen, then you were using the term incorrectly, as there are plenty of 4:3 widescreen movies. Perhaps Doom9's Aspect Ratios Explained (http://www.doom9.org/aspectratios.htm) will help.