Compressibility OR bits/pixel? - XviD Conversion using Auto GK 1.19b

[ripper2004]

I am a newbie (just a week old :p ) to this xvid conversion and AutoGK (1.19b) was really awesome. Good work developers!!
so after a few encodes and searching the forum (phew!), i have some nagging questions.

This is what i found in the forums (for good quality):
1)compressibility has to be >=60% (iam still confused abt ppl talking differently about 1CD and 2CD rips)
2)bpp(bits/pixel*frame) has to be >= 0.2 bits/pixel (a few have hinted that 0.15 is good enuf too!)

So i did 3 test encodes (2hr38min movie, Ac3, 1400MB) ..... one with Auto width and other two with min width setting.
My first question is .. why is AutoGK settling for a rather low resolution (416x208)? considering that .. it is 0.4 bpp which is way above the recommended (0.2 bpp). But again comptest value is at 68% and in other options the comptest value falls to 35%. So does that mean i throw the bpp out the window?

As u can see from the values below, the only factors different across the 3 encodes are "Resolution", "bpp" and "Predicted comptest value". Which of these shd i choose for good quality?
My requirements are: I generally rip movies around 2.5 hrs long, 1400MB, AC3

To manually check the quality i tried viewing in full screen on my laptop, so that i can find out any blurriness for the lower resolution files. They all look more or less the same (atleast to my eyes). So i want to rely only on numbers and not my eyes!

File settings/details
=====================
Filesize.....: 1,400 MB
Runtime......: 02:38:37
Video Codec..: XviD RC4 1.0
Video Bitrate: 1037 kb/s
Audio Codec..: Ac3
Audio Bitrate: 192 kb/s (96/ch, stereo) CBR

try1 (auto width)
-----------------
Resolution: AutoGK chooses 416x208 (!!!???)
bpp: 0.4 bits/pixel
predicted comptest value: 68.81

try2 (min width 576)
--------------------
Resolution: 576x288
bpp: 0.21 bits/pixel
predicted comptest value: 35.89

try3 (min width 640)
--------------------
Resolution: 640x320
bpp: 0.169 bits/pixel
predicted comptest value: 35.39

[gircobain]

The fact that try1 comes out with such a low resolution, and try2 and try3 with low compressibility (despite decent resolution) just means that the clip is not compressible enough to fit into 1400mb with reasonable resolution.
These are 3 related variables: "file size", "resolution" and "compressibility". Usually, you determine "file size", and AutoGK plays with "resolution" to get decent "compressibility", also using custom matrices or different resizer to increase compressibility if need be. So if final resolution is not acceptable for you, your only option is to increase "file size".

[jggimi]

Don't be confused by bits/pixels*frames values. It is easy to get tangled up in them.

The recommendation of >0.2 b/p*f is for estimating initial resolution prior to your first compressibility check.

After that, you may ignore the b/p*f value and instead use the percentage of maximum b/p*f returned by compressibility test(s).

It is recommended to make additional compressibility tests if you alter the resizing filter or make other significant changes.

[gatormac]

It would be nice if you could run a compressibility check only like you can in GK....I know, I know, Lenox...this isn't GK and isn't going to be :D However, it would be nice to run a comp test so that you could make better decisions on your output settings without leaving it up to chance. Right now if I use AutoGK I will run a comptest first with GK to give me an idea what quality at what filesize I am looking at as I like to set a fixed resolution. That way guys like ripper2004 will know that movies like Saving Private Ryan will need way more than 1400MB at a reasonable resolution and won't have to waste the time of an encode to figure that out.

[ripper2004]

Thanks all for the help.
So final say is "compressibility" then!

So i guess i am going to use 60% for large movies(2.5-3hr) and about 70/75% for small movies(1-1.5hr) for 1400MB file size.
I was also thinking ... if i disable AC3 and use VBR MP3 192/160 instead, i might improve the video quality a bit more.
I think AC3 has all the surround effects and stuff .. that i dont wanna lose. But we sometimes have AC3-6ch and AC3-2ch. I am definitely gonna keep AC3-6ch.

What about AC3-2ch? Is it worth the extra space at all? Will it have all the good surround stuff and all?

[gircobain]

AC3 2.0 is stereo

Keeping the AC3 track gives you the ability to play with DRC (dynamic range control) if you pass it through a decoder able to handle it, which is lost when you convert it to mp3.

Since AC3 2.0 is usually encoded at 192kbps, it makes no sense converting it to mp3 at same bitrate, because it won't make up for any room saving and will degrade sound quality, given that mp3 is a lossy codec.

[ripper2004]

Thanks again.
Well, so i would probably go down to 160kbps mp3 at the least. so i guess there's no significant increase in video quality .. so i might as well keep AC3.

Now going back to the original discussion,
I want to run compressibility tests first and find out the best resolution for about 60% compressibility.

So i guess i have to use gordianKnot 0.28.8 for this. I just saw this thread:
http://forum.doom9.org/showthread.php?s=&threadid=44414
But i can't find the first setting itself!
i am not able to find these (xvid GKnot guide) either:
http://www.doom9.org/gknot-xvid.htm

could you help me?

[gatormac]

@ ripper2004

It doesn't matter how long a movie is as to the final filesize you shoot for. There are some 2 hour movies that you can fit at 1GB at a constant quantizer of 2 (super quality) whereas there are some 1 hour long movies (like Band of Brothers episodes) that take up 1.25 to 1.5GB per hour episode at a constant quantizer of 2. It all depends on how complex scenes are and how many complex scenes are in the film....also complex bright scenes are more difficult to compress than complex dark scenes....and some directors add noise or grain to the film which make it even more difficult to compress. So don't get the idea that longer movies require higher filesizes than shorter movies....it just isn't the case.

What you should do if you want to keep the AC3 2 or 6 channel track and encode at a certain resolution do this:

Use Robot4Rip to Rip the movie from DVD (selecting the audio track you want)...it will also index and demux the resulting VOB for you....don't mess with converting audio as you don't need it (and it will save you a bundle of time). Once Robot4Rip is done open up Gknot, go to the lower right hand corner, hit reset and OK, hit rename and rename the setting. Click on the bitrate tab at the top and go to the upper right hand side and select XVID as your codec. Then go to the bottom left hand corner and select open. Browse to the .d2v file that Robot4Rip created for you and select it. A window with the video will open up...keep it open but get back to the main GK screen. Just above the open button there is a section for selecting your audio file.....check size and click select....it should already be in the correct directory, just select the audio file that you want (there should only be one). Go to the right hand side of the screen underneath the XVID logo and increase the filesize to 1400MB (since thats what you are aiming for). Click on the resolution tab at the top. Check the video type (PAL or NTSC) check the AR (4:3 or 16:9) and go down to the resolution slider and slide it to your desired resolution. Then hit Auto Crop, let it do its thing, then hit smart crop all. Click the options tab at the top and select XVID first pass button. Select load defaults and hit OK. Then go to the video window, hit save & encode, go down to compressibility check, check the use button and select now and OK. The compression check will take a few minutes and will spit out a % at the bottom. Go back to the bitrate section and adjust filesize until the percentage is at 60% (or whatever you want it to be).

This is a very basic instruction and I have to go to Church right now, will help out more later if you need it. Good luck.

[ripper2004]

@gatormac

i tried the settings in GK.
But i already have a d2v file that autoGK created previously.
But when i load it .. it gives me an error , "file is not a dvd2avi, avi or avs file".

One more question,
I had been using AutoGK and i think it uses some auto-codec settings.
But the Gordian Knot guide asks me to perform these one-time codec settings .....
http://www.doom9.org/gknot-main5.htm

Since i switch back and forth between GK and AutoGK ... Should i do this every time i switch from AutoGK to GK?

[jggimi]

As far as I know, you will only need to make codec settings one time in Gknot; these are kept in the Gknot registry entries, and will be reused each time you start an encoding job without adjusting codec settings for that job.

[gatormac]

Really, there's no reason for you to switch back and forth between the two programs if you don't have to. Is filesize a big concern to you? If it isn't I would just use AutoGK, select 60% quality and an acceptable resolution (I wouldn't go lower than 640 myself) and let AutoGK do the rest. The only thing is that you will get varying filesizes.

Or you could use GK instead. The instructions I gave above have you just a few steps away from a full GK encode. The only thing left after the compression test is to do the actual encode which is no more than pressing a couple more buttons.

I'm not sure why GK isn't accepting your AutoGK d2v file...did you erase the VOB fileset? If the d2v file has nothing to point to its useless. Do you have Robot4Rip? Start from the beginning if you do and see if that helps.

As for XVID settings, I'm pretty sure AutoGK uses fairly basic settings. Try these in GK: For First Pass tab AS@L5, click the "more" button next to AS@L5. Make sure the adaptive quantization, interlaced encoding, quarter pixel, and global motion compensation are all UNCHECKED. B-VOPS is checked, max consecutive B-VOPS 2, quantizer ratio 1.50, quantizer offset 1.00, packed bitstream UNCHECKED, closed GOV CHECKED. Click OK to get back to the main XVID gui. In encoding type select Twopass-1st pass. click the "more" button next to it and make sure "discard first pass" is selected. Click OK to get back to the main gui. Click on "Advanced Options". Motion search precision set to 6, VHQ mode set to 1, Use chroma motion is CHECKED, Turbo on or off doesn't matter, frame drop ratio 0 and maximum I-frame interval 240, cartoon mode UNCHECKED. Click the quantization tab at the top, the boxes should be this sequence: 2,31,2,31,2,31. Trellis quantization is CHECKED. Click OK to get back to main gui. Click OK to get back to GK screen.

Click XVID second pass tab. Change encoding type to Twopass-2nd pass. Check advanced options to make sure they match your first pass settings. The "Target size(kbytes)" box is where the target VIDEO FILESIZE goes (You find this value on the GK bitrate screen at the lower right hand side named "video size"). Select OK to return to GK.

As Jggimi said you only have to make these settings once (except for the target filesize which you will input after every compression test).

After the compression test, when you have the resolution, filesize, and compression % where you want it, all you have to do is open the video window, select "Save & Encode", select "save & encode" again, select "save", select "just mux", click the XVID tab and select "Add job to encoding que", then click OK to start the encode.

Thats all there is to it (keeping it simple anyway). If you are willing to go through the steps to do a compression test, there really is no need to use AutoGK as there are only a few more button clicks to start the encode in GK.

Let me know how it goes.

[gatormac]

I'm pretty sure GK doesn't use correct interleave settings by default yet, so when you check "just mux" you need to also fill the 2 boxes below that from 1 and 500 to 3 and 96.

[ripper2004]

gator, looks like u posted the message just as i was typing this. Let me edit this. thanks for taking time to answer in detail.

Disregard my problem about "not able to load the .d2v file" message above. I found a solution, R2R doesn't wanna produce a d2v file. I read that its still under development or something.
so i opened dvd2avi manually to create the .d2v and audio file. The compressibility test works...thanks. So as u suggested that after compress test its only a few more steps to start encoding, can i follow this sequence of manually opening dvd2avi=>creating the d2v file and audio file=> compressibilty tests until i get desired values=> Encode ?

One little concern for the compress test.
I ran the compress test on a particular resolution and got 70%. Now when i change the resolution slider, it dynamically changes the compressibliity value (predicts the new compress value). Should i run the test again on the new resolutiion or just adjust this thing until i get the % i want?

Thanks.

[gatormac]

By all means, if you know how to use DVDDecrypter and DVD2AVI you need not use Robot4Rip at all. You sound like the "tinkering" type and know how to use some of the programs already, so AutoGK may not be for you.

If you have already ripped the movie in DVDDecrypter and index/demuxed in DVD2AVI(dg) and have made it through your first compression test you only have a few more steps to go as I mentioned above. If it gave you a comp test of 70% and you are shooting for 60% I wouldn't change the resolution, but the filesize instead (unless you HAVE to hit a specific filesize). After changing the filesize and reaching 60% just go through the steps mentioned above and your done...no need to re-test. If you have to hit a certain filesize you could adjust the resolution, but I doubt you would hit 60% exactly as the changes are going to be more drastic than if you adjusted your filesize. I don't think a re-test is necessary even in this situation, unless your resolution change was a drastic one.

If you are shooting for 1400MB, most movies can be encoded at a high resolution and a higher quality than 60% to reach that. I wouldn't encode less than 70%, but that is all subjective. Give it a try and let us know how it turned out....I'm sure after a few encodes your methods and output desires will have changed.

[ripper2004]

Yes I am the tinkering kind ! LOL
I used to use smart ripper=>DVD2AVI=>TMPGEnc to convert my DVDs to VCDs. I am not new to using tools (I prefer things where I know whats going on). But AutoGK seems to go through 3 more steps before compress test (some avi synth, vdubmod etc stuff which i dont know and dont think are required at all).

One more observation .. my movie was being seen as 4:3 eventhough its a widescreen movie. That explains why AutoGK was choosing 446x308 eventhough i was able to get the same good quality even at 640x350 ..... the movie was more compressible.

Thanks to GK, i can now set the 16:9 myself. Also this gives me the option of manually giving the audio file (i have a movie with DTS only track and i need to convert it to wav and feed the audio manually)

Thanks a lot gatormac, i am ready to do encodes now on my own.

[TheSeeker]

I personally never use the compressiblity check. I find that with gknot the size can be predicted with pretty good regularity. what i do is load up the .d2v file and with a longer movie or one that i really like with high action i specify a size of 1350mb then i go to the resolution tab and i auto crop. make sure the 16:9 or 4:3 is set correctly then i play with the resolution till the bpp is about .23-.27. I then move on to set the credits start and save and encode. and every time i get an output file that is almost always 20-25 mb over what i specified. Looking back right now that is prolly because the bpp is so high. if you want even more accuracy just go a little lower bpp.. my point being dont bother with the compressibility. because gk has always gotten near spot on every time for me. just make sure your resolution is as high as you can make it and still be right around .22-.25 or so and you should be fine. at least that is what i have found in a couple years of using it.

Oh and just a suggestion. Learn to use GK. Not auto gk.

[gatormac]

Originally posted by TheSeeker
I personally never use the compressiblity check. I find that with gknot the size can be predicted with pretty good regularity. what i do is load up the .d2v file and with a longer movie or one that i really like with high action i specify a size of 1350mb then i go to the resolution tab and i auto crop. make sure the 16:9 or 4:3 is set correctly then i play with the resolution till the bpp is about .23-.27. I then move on to set the credits start and save and encode. and every time i get an output file that is almost always 20-25 mb over what i specified. Looking back right now that is prolly because the bpp is so high. if you want even more accuracy just go a little lower bpp.. my point being dont bother with the compressibility. because gk has always gotten near spot on every time for me. just make sure your resolution is as high as you can make it and still be right around .22-.25 or so and you should be fine. at least that is what i have found in a couple years of using it.

Oh and just a suggestion. Learn to use GK. Not auto gk.

@ ripper2004 and anybody else new to encoding

No offense to TheSeeker, but I would NOT recommend taking that advice. The compressibility check is more about getting the quality that you want, not about hitting a certain filesize. For instance, in ripper2004's encode in his first post he was getting a comp test value of 0.4 bits/pixel...and it still was in the 60's as far as percentage. You can also see that when the bits/pixel fell to 0.21 and 0.169 FOR THIS MOVIE AT THOSE RESOLUTIONS the resulting comp test was roughly 35%. The quality will be exponentially worse when going from a 70% encode to a 30% encode....some movies will be nothing but blurred macroblocks.

Some movies 0.22-0.25 bpp is fine. Other movies will require only 0.17-0.20 bpp. But there are many movies that need 0.25-0.40 bpp for an acceptable output. Every movie compresses differently and therefore requires different bits/pixel. Try a compression test on Lost in Translation and compare it to a compression test on Saving Private Ryan . LIT will be a very low bpp and SPR will be extremely high. Encode each with 1350MB and 0.25 bpp and see what kind of quality you get. I guarantee you that LIT will be around 100% quality (Q of 2 average) at a high resolution of 704 and SPR will be around 35% quality (roughly a Q of 6 average) at a low resolution of 544. But there filesizes are the same....hooray!

If you want wild fluctuations in the quality of your movies and don't mind watching artifacts/macroblocks, then by all means disregard the compression test and go strictly by bits/pixel. Or you could take the advice of Jggimi and reread the third post in this thread: The recommendation of >0.2 b/p*f is for estimating initial resolution prior to your first compressibility check. Nothing more, nothing less.

Don't get in the trap of caring about the bpp. Don't get confused into thinking the comp test is what gets you to a certain filesize. The comp test is for quality assurance at given filesizes/resolutions.

[ripper2004]

I trieds my first encode with GK .... it looks like crap!
I had 2 audio tracks ... AC3-2ch and AC3-6ch. I selected 6ch, did that take up too much space?
My settings were: 68% compress, 0.221bpp, 1400mb, 608x320, AC3-6ch, 2hr38min.

I set my file for encoding at night and slept, when i woke up 7 hours later there was an error dialog "stats file not found!". I hit OK and it continued for a few minutes and said job finished.

The quality looks pretty bad ... no sharpness .. blurry. I had much better results with AutoGK.
I used codec settings exactly as given here
http://www.doom9.org/gknot-main5.htm

reply to seeker:
I am using AutoGK now .. the output shd turn out fine i guess.
So setting the initial resolution for>0.2bpp and using compressiblilty to get values around 60-70% in GK and then use AutoGK for encoding seems to be the plan that has worked for me till now.

As you said the file was crappy because maybe it went thorugh only 1 pass. Whats a stats file? i don't know why it wasn't there.
This is how i went about it:
DVDdecrypter => DVD2AVIdg => load d2v file in GK => compress test=> settings => encode

[TheSeeker]

you know i agree with you Gatormac to a degree.. but what i dont agree with is the fact that you make it sound like the results will very from one end of the spectrum to the other. Maybe you have seen this happen, i dont know how you encode your movies, but in my personal experience i have never seen that wildly of flucuating qualities. I agree that yes the way i do it you will get slightly different qualities depending on the the amount of motion in the movie. but i disagree that it will be that completely different. Lets look at lost in translation. recently i did encode that movie the way i stated above an your right it came out perfectly. but then on the other hand i also did The Rundown like that too and which i would consider to be on the slightly more high end of high motion and it also came out perfectly. In short you probably should put more stock into the compressiblity check than i do.. But dont let it be the be all and end all of your encoding.

Well Ripper2004... its sounds like it wasnt completed sucessfully espeically since the stats file wasnt found which i should say is quite important especially in multi pass encodes. just by doing a quick look at your settings the movie should have come out pretty darn decent. something isnt right. it should have found the stats file. which is the file that is made on the first pass and stores all the settings for variable bitrates and such to use on the second and subsequent passes.

*prepares for flaming* Just a suggestion. Get divx pro 5.1.1. In my experience so much friendlier to work with.

You know what, just ignore me. Im so out of it today i cant think. but i DO prefer divx over xvid.

[jggimi]

...I selected 6ch, did that take up too much space? Let me do some math:Assumptions:
DD 5.1ch is 448 kbps DD 2.0ch is 192 kbps NTSC Force Filmed (already 23.976fps)

Known:
Content length: 2 hours, 38 minutes
XviD video codec
1400 MB .avi produced

With 6 channel .ac3 (5.1ch DD):
5MB AVI overhead
506 MB for audio
889 MB for video
Video bitrate 786 kbps

With 2 channel .ac3 (2.0ch DD:
5MB AVI overhead
217 MB for audio
1178 MB for video
Video bitrate 1042 kbps

I would think video bitrate might play a big role in perceived quality. If you used the 2.0ch DD soundtrack instead of the 5.1ch DD sountrack, you would have 289MB additional space for video. If you wish to retain the 5.1ch soundtrack, consider a 3-CD encoding.

If you went with 128kbps vbr mp3, the overhead would increse to 9MB, but the reduction in audio track size to 145MB would provide a video bitrate of 1103. I'm not sure there would be significant benefit in dropping to MP3 to go from 1042 to 1103kbps.

[ripper2004]

Thanks jiggmi ... i did notice that the final video bitrate was 640kbps. Thats why i suspected the Audio.
I should have used 2ch AC3.

Now iam encoding the video with AC3-6ch using AutoGK at home .. the result should be ... crappy (as we would expect!)

[manono]

TheSeeker-

...but what i dont agree with is the fact that you make it sound like the results will very from one end of the spectrum to the other.

gatormac is right. It can vary from one end of the spectrum to the other. Now, if the only movies you back up are Hollywood's latest and greatest, all nice and clean, the DVDs made from good source materials, then your method may work much of the time. But if you branch out a bit, and do some "foreign" movies, some old classics, some silent films, DVDs from scratched and nicked source material, from grainy material, nasty looking interlaced documentaries, concert DVDs with flashing lights and handheld cameras, heavy action martial arts films from Hong Kong, very long and dance filled Bollywood movies from India, and many other kinds, then you'll quickly find out that your method may not work all of the time.

*prepares for flaming*

I hope that didn't come across as a flame. It's just that I think there's a whole more out there than you've seen so far. The compress test as performed by AutoGK or GKnot is the best way to take all these variables (and not only motion) into account.

[ripper2004]

@manono

Yes i was trying to encode one such bollywood flick.
One more problem is ... most of my indian DVDs are being seen as 4:3 eventhough all are widescreen movies. Maybe manufacturers of these indian DVDs are not putting enough info about the picture. Even dvddecrypter says its a 4:3!

So if i use AutoGK auto resolution mode ... it does wrong compressibility calculations. Widescreen movies are 15% more compressible but AutoGk (thinking its a 4:3 movie) ends up with low resolutions of 416x208 etc.

So manually setting 16:9 and doing compress check in GK and finding the best resolution for my filesize is the way to go for me.

[gatormac]

@ ripper2004

I'm not sure why GK isn't recognizing or finding your stats file....I have never experienced that so I'm not sure what is going on with your setup. I did a quick search and didn't find anything relative. Open up GK and go to the options page. Click on XVID first pass button and then click on the "more" button next to Twopass-1st pass. You should be at the 1st pass discard or full quality pass screen. At the top should be the location and name of the stats file. What is the name and location and can you find the file manually on your PC? It almost sounds like you accidentally set up the first pass with "single pass" instead of "Twopass-1st pass". That would probably result in two passes being made and an error stating that no stats file could be found....mainly because GK doesn't allow single pass XVID encoding, yet even though you selected "single pass" I think it will still run a 2-pass encode.

Also, instead of learning how to use GK with full movies, try saving yourself some time and try to successfully encode a short trailer. Once you can encode the trailer then the movie will be the same process.

There is nothing wrong with using AutoGK, but you just don't have the control over some things that you do with GK or manually in VDub(mod). Otherwise its a great program for "non-tinkering" encoding.

EDIT: I just recreated your situation by setting a 2-pass encode with a first pass set to single pass and the same thing happened to me....an error message stating that the stats file couldn't be found. It didn't run a second pass like I thought it might, but it did leave a video file that had the qualities of the single pass setting, in this case a constant 2.5 quantizer. That could explain why your quality was so bad....when you check to see if you accidentally ran a single pass encode for your first of two passes, see what the target quantizer or target bitrate for the single pass was set to.

Don't give up on using GK...you will get great results once you get down the routine.

[manono]

ripper2004-

most of my indian DVDs are being seen as 4:3 eventhough all are widescreen movies.

Quite a few 4:3 DVDs contain widescreen movies. 4:3 and 16:9 are DARs (Display Aspect Ratios) which tell the DVD player how to resize the movie. A 4:3 widescreen DVD is much inferior to an anamorphic 16:9 DVD because quite a lot of the film's resolution is lost. But if DVD2AVI tells you it's 4:3, in all but a very few cases, you can trust it. Another place to find the DAR is in the Stream Information text file that DVD Decrypter gives you when it finishes.

Maybe Doom9's Aspect Ratios Explained Article (http://www.doom9.org/aspectratios.htm) will help make it clearer.

If both DVD2AVI and DVD Decrypter say it's 4:3, you'd better believe it (unless there was a colossal authoring error). If the compress test result recommends 416x208, then I think you'd best use an extra CD for the movie (and then check what the b/p*f says). Switching to 16:9 is guaranteed to give you bad AR. After setting GKnot to 4:3, and cropping and choosing a resolution with low Aspect Error, then click on View above the .d2v video picture, and then click Resized, and the people should look normal, and round things round. That won't be true if you then switch to 16:9. Try it sometime. Resize the picture, and then switch back and forth between 4:3 and 16:9. It shouldn't be hard to tell which is correct.

[ripper2004]

@gatormac
Sorry for the faux pas. I was using AC3-6ch audio and it took 573mb of my 1400mb file size. I didnot realize it. That was the reason why my video bitrate fell down to 600kbps and looked crappy. I got the same result when i used AutoGK with AC3-6ch too! I will try my hand again at GK. I might have also done that mistake of not setting multi-passes thing that u talk about. i will see it later, my laptop is cooling down now after 18 hours of encoding! :cool:
Thanks for the patient and detailed replies everyone.

@manono
I guess my DVDs are 4:3 letterboxed. They don't have any "widescreen" written on them.
But one DVD says "Anamorphic widescreen (16:9)" and it still shows up as 4:3 in autoGK.
Guess we'll never know!

[jggimi]

A few years ago, I got my wife a set of Rogers & Hammerstein musicals in a box set. Each and every one is wide screen, with an aspect ratio as wide as 2.55:1, yet each and every one has a 4:3 DAR.

This means they have lots and lots of letterboxing.

Was this a lazy authoring job or was this intentional? I can't even conjecture.