Correct SD Aspect Ratios. Feature Sugg., not question/glitch

[gaelsano]

Hello. Love the VLC work. Amazing stuff. However, there is one niggling thing. The aspect ratios for Standard Definition are all wrong.

A video at 720x480 (DVD or Blu-Ray or DVB) has the same Pixel Aspect Ratio as 704x480 (which is 10:11 or 40:33)

Likewise for 720x576 and 704x576.

DVD Players, Blu-Ray Players, Adobe Premiere (CS4+), Sony Vegas, Final Cut, etc ALL use this pixel aspect ratio.

That means, yes (!), a video with 720 horizontal pixels has a Display Aspect Ratio that is slightly WIDER than 4:3 or 16:9.

The only violators of this principle are most of the Hollywood DVDs. They use all 720 horizontal pixels and do a straight re-scale with a Pixel aspect ratio of 8:9 or 32:27. However, films are best seen on Blu-Rays, so this is irrelevant. Some studios DID follow the guidelines, see the Bond films or the Criterion Collection discs.

Standard Definition content will never be up-scaled to 1920x1080. It will only be offered at 720x480 (or 720x576). The current VLC has no option for the correct aspect ratio. (How about a checkbox for Generic vs ITU pixels on DVDs and Standard Definition Blu-Ray content for futureproofing?)

All video (not film) content is universally on the ITU system. Why must my Doctor Who DVDs always be in the wrong aspect ratio? Why must DVD-ready files that I edit be displayed this way? I shouldn't have to re-encode at 704x480 to avoid this. Ripping is also a pain in the butt with many discs and I'd rather just pop and play. This bugs even more now that we all have flat panels, which show those "ovals" so clearly.

You have a chance to be the FIRST video player software that gets this right! WiMP, MPC-HC, Totem, Dragon, Xine, etc all get this wrong. If we can have options for optimizing everything and the kitchen sink, we can have this, too, no?

For many years Adobe (with no video background, unlike Sony, for example) got this wrong and when they corrected it, there was a lot of confusion. The links below should help.

http://help.adobe.com/en_US/encore/cs/u ... db29-7fb1a

http://forums.adobe.com/thread/700836

http://help.adobe.com/en_US/PremierePro ... 524Ea.html

[Jean-Baptiste Kempf]

The only violators of this principle are most of the Hollywood DVDs. They use all 720 horizontal pixels and do a straight re-scale with a Pixel aspect ratio of 8:9 or 32:27. However, films are best seen on Blu-Rays, so this is irrelevant.

Not, it is not irrelevant. DVD are the biggest thing people watch now.

Standard Definition content will never be up-scaled to 1920x1080. It will only be offered at 720x480 (or 720x576).

Why not?

The current VLC has no option for the correct aspect ratio. (How about a checkbox for Generic vs ITU pixels on DVDs and Standard Definition Blu-Ray content for futureproofing?)

Which one do you want, and where?

You have a chance to be the FIRST video player software that gets this right! WiMP, MPC-HC, Totem, Dragon, Xine, etc all get this wrong. If we can have options for optimizing everything and the kitchen sink, we can have this, too, no?

Which one do you want, and where?

[gaelsano]

This isn't troubleshooting, by the way. This is a bug. In case I haven't made it clear, all the programs for video playing, owing to being made by programmers and not videographers, are all in the wrong. Only the programs by video business companies have gotten it right. Even Adobe had it wrong for a very long while while Apple and Sony had it correct.

Hardware players and professional software all gets it right.

I would like to see VLC have an option in one of the drop down menus to choose a custom Display Aspect Ratio OR ITU Pixel Aspect Ratios for "Square" screen and Widescreen. At the moment I am forced to watch my DVDs with the correct Pixels Aspect Ratios displayed without sufficient horizontal stretching.

Film based DVDs are incorrectly mastered. They WILL be replaced by Blu-Rays that are mastered in 1920x1080. You won't be able to buy the DVDs eventually.

Standard definition will NEVER be upscaled to square pixels as 1920x1080.

Never, ever, ever.

Why? Because it would add nothing to the picture. It would just be stretching the image at best, and interpolating and making a muck of it all at worst.

Blu-rays still have Standard Definition content, especially as extras. It's likely that eventually Standard Definition libraries will be published on Blu-Rays with higher bitrates and bigger storage, but they will not be up-scaled.

Is it really diffilcult to add this feature? There are options to stretch to exactly 16:9 and exactly 4:3 for Display, but Standard Definition content is actually 1.36:1 and 1.82:1 if it is an un-cropped 720 pixel wide image.

The only violators of this principle are most of the Hollywood DVDs. They use all 720 horizontal pixels and do a straight re-scale with a Pixel aspect ratio of 8:9 or 32:27. However, films are best seen on Blu-Rays, so this is irrelevant.

Not, it is not irrelevant. DVD are the biggest thing people watch now.

This is irrelevant because while all Hollywood DVDs will be replaced by Blu-Rays with square pixels at 1920x1080, the Standard Definition discs will not be.

Many DVDs have other problems with them. The colors are off. There is macro-blocking, etc. Many are even taken from Laserdisc instead of the film. There is no reason why people would buy the re-mastered DVDs over the re-mastered Blu-Rays. With the way computers are going and the crashing prices for TVs and BLu-Ray players and for Blu-Ray Discs, it's only natural.

There is no reason to not add a simple menu selection on the drop down menu bar that allows people with homemade videos or with properly mastered DVDs to watch them correctly. This way you could accurately screen both the majority of Hollywood DVDs and the pretty much everything produced on Standard Definition video from 1960-2005. American serials on the big networks have usually used film, but they are the exception. Most countries simply used analog and then digital video.

[Rémi Denis-Courmont]

As far as I know, VLC uses the aspect ratio specified by the input media (i.e. it does not necessarily assume 1:1 pixel ratio). If you think there is a bug, you are more than welcome to provide a patch.

[gaelsano]

First off, thank you for the prompt responses and attention. I appreciate it. On to the topic....

This matter's a bug by design, not a coding error. I don't know how to code, but I can diagnose a problem. At present, there is no way to force VLC to use the correct Pixel Aspect Ratios nor Display Aspect Ratios for Standard Definition content. DVDs do not specify aspect ratios the same way that regular files do. Metadata and all that. The simple fact is that the software has no way to show 720x480 at a PAR of 40:33 (DAR=1.82 not 1.78) or at a PAR of 10:11 (DAR = 1.36).

This is to say nothing of the fact that many video files have the incorrect aspect ratio outlined in the metadata. A lot of stuff that has fallen into the public domain is easier to find digitally than on disc, but since they're old, no one gives a damn, and the copies online could be rubbish and there is not the same enthusiasm as the New Release bootlegs. More than once I've encountered a file that had incorrect aspect ratios in the metadata. I'm talking about 1.85:1 films stretched to 16:9 or 1.66:1. I can either play with it by stretching the window (then I can't go to maximized/fullscreen) or choosing one of the existing presets that is close. Again, there is no preset for 1.85 (also known as 3/4 perf 35mm)

I have a friend who edits for a television network. It is local and much of the content is still produced in standard definition. (Asia) I can't recommend switching over to all open source software nor Linux because of problems like these. Kdenlive, Openshot, Totem, VLC, et al still don't handle this correctly. Discs should either be shown in ITU pixel aspect ratios or we should have a choice.

Video->Aspect Ratio->5:4/3:4/16:9/etc.....**1.36:1/1.82:1 (for Standard Definition with the extra 16 pixels of padding or 720x480)

OR

Video->Aspect Ratio->5:4/3:4/16:9/etc.....*Custom

Also, labeling it as "Display Aspect Ratio" and not "Aspect Ratio" would be wise.

[gaelsano]

As far as I know, VLC uses the aspect ratio specified by the input media (i.e. it does not necessarily assume 1:1 pixel ratio). If you think there is a bug, you are more than welcome to provide a patch.

I wonder if there is a communication problem between myself and yourselves. I feel like you and J B Kempf are parsing my text, seeing keywords, and then commenting on the pieces you recognize while missing my points. I apologize for having not learned enough French during high school and forcing you to go by English alone. I'll try to re-word myself.

I never said VLC ignored meta-data about aspect ratios.

I never said VLC assumes 1:1 PAR.

I said that VLC misunderstands DVD metadata.

DVDs cannot have custom metadata. They must read 4:3 or 16:9, but those are relative figures, not absolute. The tag allows to select the skinnier or the wider value. Their precise values are 15:11 (1.36) and 20:11 (1.82)--slightly wider than 4:3 (1.33) and 16:9 (1.78). 8 pixels on the left and 8 pixels on the right that act as padding. (Legacy from the old Analog to Digital capture which captured more than necessary so you could recenter the image and crop it to 704x480). DVD aspect ratio flags are meant to just say "is it a square or a rectangle" and NOT to provide the exact DAR or PAR.

The active content, the center 704 pixels are exactly 4:3 and 16:9, but the extra pixels added for legacy compatibility are meant to be cut off. Equipment should either crop those 16 pixels at the sides or the equipment should display the complete signal at a DAR of 15:11 or 20:11. The MPEG people in their very finite wisdom chose to use DAR instead of PAR which causes the confusion. 704 and 720 pixel wide images have the same PAR but different DAR. The one benefit to using DAR is that 352x480 content and 740x480 content could share the same DAR. However, it is a moot point since all 352x480 content is 4:3 and nothing is native to that resolution. They sacrificed 704x480 and 720x480 harmony for the sake of 704x480 and 352x480 harmony.

The PAR is in the DVD manual and in the ITU-R 601 manual (the latter is freely available under the old title of CCIR-601).

Buried in the Preferences menu is an option under Video to force a certain aspect ratio. It can be exact. But rather than having a pop-up menu accessible from the menu bar, I must enter the preferences screen every time that I want to change it.

There should be an option under Video->Aspect Ratio

Default for following DAR tag in the file container
5:4
1:1 Square
4:3 for standard 704 pixel-wide SD content and non-standard 720 pixel-wide SD content
4:3 ITU for standard 720 pixel-wide SD content (with extra pixels at the sides)*
1.37:1 for Academy Ratio 35mm
16:9 for 704 pixel-wide content and for High Definition content (720p and 1080i)
16:9 ITU for standard 720 pixel-wide SD content (with extra pixels at the sides)*
16:10
1.66:1 for 16mm*
1.85:1 for 3/4 perforated 35mm*
2.21:1
2.35:1 for 35mm old Scope
2.39:1 for 35mm new Scope

or

Default for following DAR tag in the file container
1:1 Square
5:4
4:3 for standard 704 pixel-wide SD content and non-standard 720 pixel-wide SD content
15:11 for standard 720 pixel-wide SD content (with extra pixels at the sides)*
1.37:1 for Academy Ratio 35mm
16:9 for 704 pixel-wide content and for High Definition content (720p and 1080i)
20:11 for standard 720 pixel-wide SD content (with extra pixels at the sides)*
16:10
1.66:1 for 16mm*
1.85:1 for 3/4 perforated 35mm*
2.21:1
2.35:1 for 35mm old Scope
2.39:1 for 35mm new Scope

or

Default for following DAR tag in the file container
1:1 Square
5:4
4:3 for standard 704 pixel-wide SD content and non-standard 720 pixel-wide SD content
1.36:1 for standard 720 pixel-wide SD content (with extra pixels at the sides)*
1.37:1 for Academy Ratio 35mm
16:9 for 704 pixel-wide content and for High Definition content (720p and 1080i)
1.82:1 for standard 720 pixel-wide SD content (with extra pixels at the sides)*
16:10
1.66:1 for 16mm*
1.85:1 for 3/4 perforated 35mm*
2.21:1
2.35:1 for 35mm old Scope
2.39:1 for 35mm new Scope

I can send a mock-up image via e-mail.

Many Hollywood Studios got this wrong because they have a background in film and not in video. They made a whole lot of other mistakes, especially with color-space conversions. The studios got their acts together for Blu-Ray and moved all of the talent there. Blu-Rays may be priced high or may still be rare in Europe, but they will eventually push out DVDs. Many retail store locations in America, for example, do not even stock the DVD versions of major releases. Much legacy content will never be available any other way, not even as digital files because the TV studios may not have money and to be honest, their DVDs were made perfectly fine to begin with.

[Rémi Denis-Courmont]

You can already add "custom" DARs in the advanced video preferences, if that's all you need.

[gaelsano]

You can already add "custom" DARs in the advanced video preferences, if that's all you need.

Oh, wow. Thank you. I had been monkeying with the settings but couldn't find that until I did a double-check.

I still feel it would be better to have DVDs default to this. Or at least have the options I listed all listed by default and in order of wideness. It is odd to find 5:4 at the bottom and then any custom DAR below that (they are also off-set in type).

I'm pretty big on standards-compliance. I'll let my buddy know about this. He's going have to inevitably upgrade his equipment within a year and would prefer not to buy more Windows and Windows products. Apple seems to be shifting from high-end/prosumer to consumer. Final Cut X and all that. I can't advise a serious investment in something with a rocky future.

I'm holding out hope for Lightworks to save Linux editing or at least provide an example. We have a litany of programs from MPlayer, VLC, the unfinished VLMC, PiTiVi, KDenLive, Openshot, Xine, Totem, Dragon, Kaffeine, SMPlayer, etc, but none seem to have the complete package.

For a while I was stuck using Windows' SubtitleEdit because none of the Linux editors offered support for .smi/SAMI.

[Jean-Baptiste Kempf]

Seriously, your posts are way tooo long... Do you realize the amount of time if everyone did it like you?

If you want us to add some DAR or some Crop Ratio, please say so. You seem knowledgeable enough to give good suggestions.

[gaelsano]

Sorry for that. I try to be exhaustive and get everything out in one post and that never works out. I have a hard time converting the mechanics of conversation into message boards. It always feels like some sort of essay submission form.

I'd really like to get Linux and FOSS up to snuff and smooth out the rough edges. I still believe the Aspect Ratio list should be a little more exhaustive and include parenthetical information like this: Display Aspect Ratio -> 16:9 (Generic Widescreen).

I'd also like to help out with the translating. I'll need to get in contact with the head of it, because the maintainer for the language in question seems to have checked out.

The reason for all of this is that I see a lot of possibilities for FOSS in Korea at last. It was only a year or two ago that they finally abolished a bone-headed software security law from 1999 that effectively mandated IE6 across the entire country for any secure work. There is a lot of talent here, but it's an idiot-savant situation where the country is masterful at hacking around the deficiencies of Windows and IE yet is unable to adopt Linux or Unix even for bank or most internet web servers.

Anyway, keep up the good work. 2.0 runs noticeably smoother than the 1 series.

[Jean-Baptiste Kempf]

But which one do you think we should add?

[mederi]

Free Aspect Ratio, please!
http://trac.videolan.org/vlc/ticket/6172
I also used too many words until I found the right expression

[gaelsano]

But which one do you think we should add?

15:11 (Digital Video)
20:11 (Digital Video Widescreen)

And also, for improperly tagged movie or movie clip files.

1.66:1 (16mm Film) <-------------- the occasional European indie flick
1.85:1 (3/4 perf 35mm Film) <------------- Action movies, non-Cinemas Scope 35mm; 3/4 height of Academy or Cinemascope film frame

Possibly, if you want to be REALLY thorough

1.37:1 (35mm Film Academy Ratio) <-----------35mm film with no CinemaScope applied. Silent-era films

[Jean-Baptiste Kempf]

Are those CR or AR, or both?

[gaelsano]

I was referring to Display Aspect Ratios.

Crop Aspect Ratios are an entirely different matter. You can't do a straight crop of DVDs. You must first unpack the pixels to 15:11 or 20:11 and then crop to 4:3 or 16:9 in order to remove the almost black padding at the right and left sides. This is the best way to display DVDs or DVD-ready files for watching. For video editors, it is more important to see all 720 pixels to double check that the extreme left and extreme right are 94% black. It prevents ringing on analog setups.

Many models of TV will take 720x480 wide and use a Display Aspect Ratio of 20:11. If I play a DVD it gets shown as 20:11. That means a horizontal sliver of pixels at the top and the bottom of the monitor are 100% black (no picture data) and at the left and right sides of the picture are vertical slivers of almost black (for 8 bit color: values 0-15 are footroom and 236-255 are headroom). These 94% black vertical slivers at the left side and the right side of the picture data are on the DVD, but are not part of the actual film or TV program.This is the default behaviour of a digital video DVD, on a hardware DVD player hooked up to a 16:9 monitor. The "Zoom to Widescreen" feature will slice off those vertical slivers of almost black at the left and right sides of the DVD content's picture giving us a 16:9 display ratio.

Hardware DVD Player and 16:9 HD Television Setup:

Default: (720x480 --(stretch)-> 1920x1056) 24 horizontal lines are dead black. 1878 horizontal pictures carry the content of the movie or TV program. 26 pixels on the left side and 26 pixels on the right side carry 94% black pixels which act as padding. They are on the DVD but are not part of the film or TV program.

Zoom to Widescreen 1: (720x480 --(stretch)-> 1964x1080 --(crop)-> 1920x1080) No horizontal lines are dead black. The "padding" has been cropped.
or
Zoom to Widescreen 1: (720x480 --(crop)-> 704x480 --(stretch)-> 1920x1080) No horizontal lines are dead black. The "padding" has been cropped.

The above is from personal experience, below is related data from videohelp forums, paying attention to broadcasting engineer edDV's posts.

http://forum.videohelp.com/threads/3277 ... -DVD/page3

http://forum.videohelp.com/threads/3277 ... id-for-DVD

(Please forgive the fact that the shots are of Jimmy Fallon)

http://forum.videohelp.com/attachment.p ... 19&thumb=1
http://forum.videohelp.com/attachment.p ... 19&thumb=1

Here's another link. Just another the "guesser" at the bottom of the page

www DOT designstudioschool DOT com/mpeg-720x480-704x480-t72839 DOT html

[Jean-Baptiste Kempf]

{ "1:1", "1:1" },
{ "4:3", "4:3" },
{ "16:9", "16:9" },
{ "16:10", "16:10" },
{ "221:100", "2.21:1" },
{ "235:100", "2.35:1" },
{ "239:100", "2.39:1" },
{ "5:4", "5:4" },

Are the ones we support now.