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AR question

Posted: Mon Sep 03, 2007 9:51 pm
by mrkb4269
I had a question about ARs and how they are handled in AniDB that I hope you guys could answer:

If a file has an aspect ratio of 16:9 (meaning it was animated/aired in widescreen), but it`s resolution is something like let`s say Black-Order`s H.264 version of Gurren Lagann (960x540) and avdump reports it`s resolution to be other than the usual (based on it's calculations using the resolution of the video track) do we identify the AR to be 16:9 or "other" in the file itself that we will be adding to AniDB?

Also, it seems that the AR is something that`s autoCREQ`ed since it gets locked after being verified but I`m curious, why are files that all have the same resolution have different verified ARs? Like for example take a look at these:
http://anidb.net/perl-bin/animedb.pl?sh ... fid=320194
http://anidb.net/perl-bin/animedb.pl?sh ... fid=320168
http://anidb.net/perl-bin/animedb.pl?sh ... fid=336355

All three of those files have the same res, but different verified ARs. How could this be?

Posted: Tue Sep 04, 2007 3:10 am
by Amour
Maybe a bug.

Posted: Tue Sep 04, 2007 3:55 am
by mrkb4269
Alright so maybe it is a bug. But do you have an answer for my first question, though? How should we deal with files like this? Should we mark the AR what it's supposed to be (for example in Black-Order's Gurren Lagann's case mark it as 16:9 even though avdump says otherwise) or mark it as what avdump tells us based on it's calculations of the resolution of the video track?

Because if I remember correctly, I once marked the AR of an episode of Pumpkin Scissors by Eclipse as "other" and one of the mods said that the actual resolution was "16:9" but it was just that the file was cropped wrong or something. So what should I do in this case?

Posted: Tue Sep 04, 2007 4:25 am
by ricce
This looks like a bug at least for f320194 -- 'unknown' should never be set on a verified entry.

f320168 is correct 960×540 is 16:9.

f336355 this may be caused by a bug as well (maybe the same bug), but it may also be caused by A/R info in the file (but it is not marked as anamorphic so that is wrong in that case).

About how to set the A/R -- for those files it is no question 960×540 is exact 16:9. in general, if only a few pixels off (caused by bad crop) set to the A/R it should have bin if cropped correctly else (including 16:9 cropped down to 4:3 etc.) set the A/R to what it is in the file.

Posted: Tue Sep 04, 2007 4:29 am
by mrkb4269
So if I'm sure the AR is 16:9 even if avdump says it's not, (like in the case of those files), just set it to 16:9? Sounds good to me. Thanks for the quick reply.

BTW, I think the bug occurs because avdump just marks whatever is there as verified, not making any changes. So if I add a file using avdump and I mark the file's AR to be "unknown" and avdump identifies it as "other", avdump will just say that whatever value is in the file entry on the DB is the correct one, without actually checking it. I might be totally wrong on that one, but that's just a guess.

Also, I can't change the ARs on those two files you mentioned that are not marked as 16:9 because like I said, they are marked as verified so they are locked. A mod will have to fix those.

Posted: Tue Sep 04, 2007 7:29 am
by epoximator
1. don't mind what avdump says @ AR, it's not up to date vs. the auto creqer (ref)
2. 960x540 is not registered as 16:9 yet @ auto creqer
3. the auto creqer does not touch AR unless it's 100% sure
4. see http://wiki.anidb.info/w/Avdump/AR

Posted: Tue Sep 04, 2007 7:48 am
by nwa
epoximator wrote:2. 960x650 is not registered as 16:9 yet @ auto creqer
It isn't marked as 16:9 because 960x650 is not 16:9 nor 4:3, it's simply plain wrong in any aspect, if it's the display resolution :D

960×540 is 16:9, however, as ricce said

Posted: Tue Sep 04, 2007 7:53 am
by epoximator
i never wrote that! the edits was for something else..

Posted: Tue Sep 04, 2007 8:50 am
by nwa
hehehe, anyway, I added it to the list now (960x540 that is), so it should be registered

Posted: Tue Sep 04, 2007 12:56 pm
by mrkb4269

Posted: Wed Sep 05, 2007 11:56 pm
by HiEv
Instead of registering individual width/height combos to specific aspect ratios, why not simply divide the width by the height and see if the result is close to 1.777... for 16:9, or 1.333... for 4:3, or etc...? Say, anything that is within +/- 0.02 of those numbers?

Posted: Thu Sep 06, 2007 6:26 am
by nwa
That's what we've pretty much done in http://wiki.anidb.info/w/Avdump/AR

The reason why setting the AR automatically by avdump hasn't been (fully) implemented is cause there are tards who encode with black bars, ie the hard resolution is wrong, but the picture itself, with black bars not included, is correct. Although mostly a relic from avi files, mkv's should be clear enough to set the AR automatically.