AR, Angles and Comp Checks

[techz]

When using gknot in the ar field, if the ar is specified on the box of the dvd like 1.66, 2.35 or 2.40 are we supposed to use this in the display ar field of gknot, becuase whne u select 16:9 u only get 1.823:1, sometimes the movie doesnt look correct in that ratio since its probably 2.40:1, just want to know how everyone else does it, normally i check teh dvd out in wmedia player but it seems that too doesnt show the correct ar sometimes, I tried Lion King 1 1/2 and it shows it in 1.778:1 ratio whereas on teh box it mentions 1.66 ratio, mpc plays the dvd correctly as 1.66:1 though.

in fact Lion King 1 1/2 seems to be a really complicated dvd to rip, it has two pgc's and each pgc has two angles all the same lenght, i read teh guides and based on that choose the first pgc and first angle. But since the movie is only 77 mins long, i have to raise the res all the way to 688x3xx to get a comp check barely below 100% w/video @1075kbps and audio @192kbps

for a 70% comp check i have to set teh res to 720x4xx

[Soulhunter]

Originally posted by techz
When using gknot in the ar field, if the ar is specified on the box of the dvd like 1.66, 2.35 or 2.40 are we supposed to use this in the display ar field of gknot, becuase whne u select 16:9 u only get 1.823:1, sometimes the movie doesnt look correct in that ratio since its probably 2.40:1, just want to know how everyone else does it, normally i check teh dvd out in wmedia player but it seems that too doesnt show the correct ar sometimes, I tried Lion King 1 1/2 and it shows it in 1.778:1 ratio whereas on teh box it mentions 1.66 ratio, mpc plays the dvd correctly as 1.66:1 though.
The initial AR (4:3 or 16:9) is only representative before cropping... ;)


Bye

[manono]

Hi-

When using gknot in the ar field, if the ar is specified on the box of the dvd like 1.66, 2.35 or 2.40 are we supposed to use this in the display ar field of gknot, becuase whne u select 16:9 u only get 1.823:1, sometimes the movie doesnt look correct in that ratio since its probably 2.40:1,...

Don't they teach how to write sentences in school anymore? You know, periods and capital letters?

Don't confuse the movie's AR (1.33:1, 1.66:1, 1.85:1, 2.35:1, etc.) with the DAR (Display Aspect Ratio-4:3 or 16:9), which tells the DVD player how to resize the video. The movie ARs are only approximations anyway, and they can vary quite a bit from what's stated on the DVD box. For example, I've found so-called 2.35:1 movies to vary from about 2.25:1 to 2.45:1.

I haven't done Lion King 1 1/2, but also found The Lion King to be 1.78:1, instead of the stated 1.66:1.

As long as you have either 4:3 or 16:9 correctly applied in GKnot, and crop and resize to low Aspect Error, then you can't go wrong.

As for the high compress test result, you can do some things to get that percentage down a bit. You can drop B-Frames if you're using them. You can use a sharper resizer (LanczosResize, if not using it already). You can use better quality audio (the AC3 if not using it, or a higher bitrate MP3). You can drop any smoothing filters you may be using, or, as you found out, use a higher resolution. If you're using XviD, apply a sharper Matrix (MPEG instead of H.263, or one of the really high bitrate Custom Matrices).

[techz]

I never crop, yes its wrong, i'm supposed to crop, so from today onwards i'll use auto crop for all my rips, hopefully it knows what its doing more than i do :) I normally used WMP9 to see how the video looked on my monitor and then when i preview the d2v in gknot after doing the settings i would compare the two, thats how i knew it was correct. i assumed after reading the material on AR and DAR that cropping cuts out parts of teh actual video, now i dont want to cut out parts of the borders of my movie, so i never cropped, but seeing as though the AR on the box of the dvd is not always correct (The Lion King 1 1/2 says 1.66 but when i auto cropped it said 1.74:1 and AutoGK says the same, i guess it uses AutoCrop too) i guess its safer to auto crop/autogk rather than use my bad judgement. Although I've noticed with auto crop also a few pixels of the original movie are lost, so how do i avoid losing pixels?Answer again i dont use autocrop but i'm back to where I started, only 2 of the all the dvd's i've ripped had black borders on the sides so those would probably need to be cropped out/or i can use autocrop and see to it that i dont loose any pixels. is this the real function of cropping to remove teh black bars at the side, because i feel that there's more to it that i'm not getting..

Check the steps-

Step1 Load the d2v file,
Step2 Select the codec, a/v bitrate(i can handle this)
Step3 in the Resolution Tab first select NTSC/PAL,
Step4 Then select 16:9/4:3
*Do I ever choose "Display AR" and set it manually?
Step6 Do an autocrop and according to the auto crop AR set my final resolution to reduce AR error
Step7 etc.

Now in doing all this, if i want to avoid cropping, whats my alternative, other than for using autogk, because i doubt all 16:9 movies are 1.778:1 Aspect Ratio, some are definately going to be 2.xx:1. This is why i asked in another thread, that professionals like urselves make a sort of db where we can go and check out "Recommended Settings" for each dvd, make use of all that work u members have done.

---------------------
Taken from Resolutions, Aspect Ratios And The ITU-R BT.601 Standard Pg1 :

"If you use the Auto Crop, be sure and scroll the .d2v afterwards to make sure it did it correctly and that the Aspect Error is low"
--Doesnt the Aspect Error depend on what final resolution u choose?

@manono
What do u mean u found Lion King to be 1.78:1 rather than 1.66 ? BTW I cropped all teh black bars from the file and I got 1.696:1 AR for LK 1.5

Just want to mention I really, really appreciate all the help.
I'm a troublesome member arent i ;)
Just wish i could forget all about this and start over again

[manono]

Hi-

i assumed after reading the material on AR and DAR that cropping cuts out parts of teh actual video, now i dont want to cut out parts of the borders of my movie, so i never cropped

If you'd rather leave behind some of the black bars rather than cut into the video by a few pixels to get low AR with your chosen resolution, then that's up to you. But I would never do such a thing.

so how do i avoid losing pixels?

You don't, assuming you want low Aspect Error. I really don't understand what the big deal is over cutting out a few pixels. You could try a different resolution, which might allow you not to crop pixels from the video. Or you could set the W-Modul to 16, instead of the default 32, and that might also allow you not to crop any pixels from the video, depending on the resolution.

is this the real function of cropping to remove teh black bars at the side...

Yes, and also to allow you to get a low Aspect Error for your chosen resolution.

Do I ever choose "Display AR" and set it manually?

Not if you work only with standard 4:3 or 16:9 DVDs, and crop and resize in the standard way.

Doesnt the Aspect Error depend on what final resolution u choose?

Yes. I mentioned that because at the time it was written, AutoCrop didn't work well. I don't know how it works now, because I never use it.

What do u mean u found Lion King to be 1.78:1 rather than 1.66 ?

Both IMDB (http://www.imdb.com/title/tt0110357/dvd) and Amazon.com (http://www.amazon.com/exec/obidos/tg/detail/-/B00003CXB4/002-7127848-8729620?v=glance&s=dvd&vi=tech-info) claim it to be 1.66:1. They say the same thing about Lion King 1 1/2. But after cropping and resizing to 704x400 (2 CDs), it's 1.76:1 (sorry-not 1.78:1 as I stated before). The final AR will depend on the resolution, but it's definitely not 1.66:1. Just trust GKnot. It won't let you down.

I just ripped a chapter of my Lion King DVD, and after cropping away the black bars, I get 1.747:1. When I ripped it, I cropped a bit more to follow the AviSynth rules, and to lower the Aspect Error, and so it's 1.76:1 with 0.1% Aspect Error. When I play a 1.66:1 DVD on my widescreen TV, I get small black bars on the left and right sides. But The Lion King has no such bars. It completely fills the screen. It's not 1.66:1. At least the R1 DVD isn't. I don't know about the DVDs from other regions.

I'm a troublesome member arent i

Yep.

[techz]

GMC/Qpel, Do any of u notice the difference or d u keep it off, and it seems selecting a profile still doesnt allow us to use Qpel and GMC so since i was considering buying a new Divx Player, can teh new ones support this even if i stop using a profile?

And how about Psychovisual Enhancements, I read doom9's guide on that too and from my understanding its most useful for long movies on 1 CD, i.e. low bitrates. The guide needs some more info and needs to be updated:rolleyes: