Aspect Ratio help: What ratio is this?

[bergqvistjl]

The following complete image is 1024x576 with an aspect ratio of 16:9 and the section in the blue box is a central 4:3 cutout at 720x576.

What's the ratio of the whole actual image (minus the black bars - you can leave a few pixels of them on either side if it means you get a known standard ratio)?

Is it 14:9? And what would the resolution be in this case?

[manono]

...the section in the blue box is a central 4:3 cutout at 720x576.

If it's 720x576 then it's not 4:3 but 1.25:1. Anyway, what's the source of this image? Did you create it? Have you satisfied yourself that it's in the correct aspect ratio (round things are really round and not ovals)? Just cropping the black away leaves an aspect ratio of about 1.4:1 so something is probably off.

My guess is it's from a 4:3 source, with the black bars added for some reason.

Crop(108,0,-108,0)
Lanczosresize(768,576)

[Skiller]

More detail about the source would help narrowing down the cause.

My first idea was, someone took an NTSC DVD (720x480) and put it in a square pixel 16:9 frame without accounting for the rectangular DVD pixels. Upon close inspection that does not seem to be the case as after cropping to the 1.5:1 SAR of 720x480 the remaining black borders at the sides are still much thicker than what you would typically see on a DVD source picture.

If we just cut the sides (left and right only) we are left with about 808x576. That's 1.40:1. So it's not 14:9 either. More like someone slightly zoomed a 4:3 frame to make the pillarboxing smaller, but then why is there still some borders left at the top and bottom? Sounds like an error to me.

[bergqvistjl]

More detail about the source would help narrowing down the cause.

My first idea was, someone took an NTSC DVD (720x480) and put it in a square pixel 16:9 frame without accounting for the rectangular DVD pixels. Upon close inspection that does not seem to be the case as after cropping to the 1.5:1 SAR of 720x480 the remaining black borders at the sides are still much thicker than what you would typically see on a DVD source picture.

If we just cut the sides (left and right only) we are left with about 808x576. That's 1.40:1. So it's not 14:9 either. More like someone slightly zoomed a 4:3 frame to make the pillarboxing smaller, but then why is there still some borders left at the top and bottom? Sounds like an error to me.

It is from a 16:9 anamorphic PAL DVD. The source is from footage which was wider than 4:3 yet not as wide for true 16:9

It's from the PAL Transformers The Movie: Reconstructed DVD. It's the raw animation frame (which would normally be cropped to 4:3 for actual release), which explains why the image itself is wider than 4:3.

I added the 4:3 blue-border myself, so it may not be accurate. The original screencapture was from the DVD, which (as its anamorphic) i've stretched horizontally to get the correct aspect.

Here is the original raw frame from the DVD if you want to ignore my attempt & creating a 4:3 cut-out & try again:

The black bars either side are part of the image as it is on disc. All i've done is stretch it because it's anamorphic. Here's the original without stretching (the above stretched version is the correct one):


Basically, the animation frame you see above would have been matted slightly to create a 4:3 transfer (and matted further for 16:9 transfers) for theatrical or previous home video relases. With this release, they've removed the mattes to show the full animation frame. This is how that full frame was presented on disc. I'm trying to work out the ratio of what that full frame would be (and if the vertical resolution is still 576, what the horizontal resolution would be for that ratio).

Just to make things easier, i'd like the ratio to be worked out without cropping off the tiny black bars top & bottom - so working it out from the full height of 576).

Ultimately i'd like to know if the ratio of the full frame conforms to any known standard (e.g. a standard animation cell size for the mid 80s)?

[smrpix]

It's possible you're looking at a transfer from full aperature 35mm in which case the aspect ratio is ~1.37:1. That comes pretty close to a standard that matches your frame size (crudely measured by photoshop.)

It's also possible someone just blew it up a little and cropped off the top and bottom of the image from the negative.

What's your goal?

[bergqvistjl]

It's possible you're looking at a transfer from full aperature 35mm in which case the aspect ratio is ~1.37:1. That comes pretty close to a standard that matches your frame size (crudely measured by photoshop.)

It's also possible someone just blew it up a little and cropped off the top and bottom of the image from the negative.

What's your goal?

My goal is to find out the ratio of the image they've placed in the 16:9 frame. 1.375:1 makes sense (with slight black bars on the top & bottom, which they've cropped out a bit here then).

[duffbeer]

Taken from the DVDTalk.com review for this disc:

To deconstruct this "Reconstructed" edition, let's start with the choice of aspect ratio. As mentioned earlier, Transformers: The Movie was made as a theatrical production and played in theaters at a ratio of 1.85:1. Yet it was also made with the knowledge that it would probably have a longer shelf-life on home video and TV. Previous video editions have all presented the movie in 4:3 full-screen, which actually isn't far off from how the animation was originally drawn. However, fans have clamored for years to see a theatrical widescreen presentation of the movie. Rhino Home Video claimed that they explored this option before releasing their DVD but couldn't locate any proper widescreen source elements. Many arguments have ensued throughout the fan community about what is truly the Original Aspect Ratio for the film. Is it the 1.85:1 ratio it played at in theaters, the 4:3 ratio it played on in television, or something in between?

Somehow, Metrodome has managed to go back to the original animation elements and has retransferred them to be shown not at any one particular fixed aspect ratio, but rather presented so that we can see everything that was originally drawn, the entire animation cel, regardless of what ratio it appears in or whether there are shot-to-shot variances throughout the movie. On the one hand, this almost sounds like a noble idea. Without an official word from the film's creators, if the fans can't decide what is the proper ratio why not just show everything that's there? The artwork had to be drawn, after all. This isn't like an open-matte live action movie where a boom microphone might dip into the frame. You'd think that if someone took the time to draw an object it must be important.

The problem comes in exactly how Metrodome displays that artwork. Even though the animation cels themselves vary slightly in width from shot to shot, they average out to a ratio of no greater than 1.4:1, which is only infinitesimally wider than a standard 1.33:1 video frame. Despite this, some bonehead in the studio made an asinine decision to present the movie picture pillarboxed into the center of an anamorphically enhanced 16:9 video frame with empty black bars on the sides.

Why is this a bad thing, you ask? Anamorphic enhancement is good, isn't it? Well, it is when a widescreen movie image fills the width of the frame; in that case the enhancement allows the picture to better exploit the entire resolution of the DVD format in both the horizontal and vertical directions, without wasting pixels on empty letterbox bars on the top and bottom of the screen. But 1.4:1 doesn't qualify as widescreen. In this case, you're using the entire vertical resolution of the DVD, but wasting a huge chunk of horizontal resolution creating useless black pillarbox bars on the sides.

Let's do some very basic math. An NTSC DVD has a resolution of 720x480 pixels (DVD pixels are not square). PAL is 720x540. In either case, the disc's horizontal resolution is 720 pixels. A 1.4:1 image pillarboxed into the center of a 16:9 frame only uses approximately 568 of those pixels, a loss of over 21% horizontal resolution.

If Metrodome had decided instead to encode the DVD in 4:3 format with miniscule letterbox bars at the top and bottom, they could have preserved the 1.4:1 aspect ratio while utilizing the entire 720 pixel horizontal resolution of the disc and only losing a miniscule amount of vertical resolution. The fact is that any movie narrower than a minimum of 1.66:1 does not benefit from anamorphic enhancement; rather, it loses more resolution in the tradeoff than it gains.

Furthermore, by encoding the image this way, viewers watching the DVD on a traditional non-widescreen television are forced to put up with large black bars on all four sides of the frame for no particular reason.

[bergqvistjl]

x

Thanks for that. There are various DVDs of TFTM out, all with seemingly unique transfers. And they all vary in proportions & ratios, so i'm struggling to work out which is correct:

Here are the following I have in cronological order:

2005 - UK 'Reconstructed' edition (Anamorphically Stretched & not anamorphically stretched) - transfer of the US version of the film:



2006 - UK 'Ultimate' edition - Disc 1 - 16:9 transfer of the US version of the film (although this looks stretched to me, but it's supposed to be presented 16:9)


2006 - UK 'Ultimate' edition - Disc 2 - 4:3 transfer of the UK version of the film


2006 - US '20th Anniversary' edition - Disc 2 - 4:3 transfer fo the US version of the film


The only one I don't have is disc 1 of the 2006 US '20th anniversay' edition. This is a 16:9 transfer of the film, but different still to the 2006 UK one i've attached.

Interestingly, if you want ANOTHER perspective, take the 2nd of my images (the non-anamorphic Reconstructed version), and stretch the image out at each side so the black bars are replaced and the image is now taking up the whole 720x576 canvas: It suddenly looks in better proportions than the anamorphic 16:9 one (to my eyes)... http://screenshotcomparison.com/comparison/181718

[pandy]

Perhaps you can search for frame with circle - it should be easy to find proper aspect ratio with circle.

[bergqvistjl]

Perhaps you can search for frame with circle - it should be easy to find proper aspect ratio with circle.

But how do I know if i'm looking at what's supposed to be a circle or not?

[jagabo]

Perhaps you can search for frame with circle - it should be easy to find proper aspect ratio with circle.

But how do I know if i'm looking at what's supposed to be a circle or not?

You just have to use your judgement.

By the way, if we assume the original 720x576 frame follows MPEG specs and resize to 1024x576 to get a 16:9 square pixel frame (which you did), then crop away all the black borders (all four sides), the remaining picture is about 1.44:1.

[bergqvistjl]

Perhaps you can search for frame with circle - it should be easy to find proper aspect ratio with circle.

But how do I know if i'm looking at what's supposed to be a circle or not?

You just have to use your judgement.

By the way, if we assume the original 720x576 frame follows MPEG specs and resize to 1024x576 to get a 16:9 square pixel frame (which you did), then crop away all the black borders (all four sides), the remaining picture is about 1.44:1.

What about if you only crop away the borders on the L&R sides and leave the vertical resolution at 576? What's the ratio then?

[jagabo]

What about if you only crop away the borders on the L&R sides and leave the vertical resolution at 576? What's the ratio then?

About 1.4:1. You can easily do this yourself: open the frame in an editor, stretch it to 1024x576, crop away want you want, the note the remaining frame size. Divide the width by the height to get the AR.

[manono]

Thanks for that. There are various DVDs of TFTM out, all with seemingly unique transfers. And they all vary in proportions & ratios

Did you not read what he wrote? Or understand it? The full review from which he quoted is here:

http://www.dvdtalk.com/reviews/18370/transformers-the-movie-reconstructed/

The review is of the R2 British 'reconstructed' version of the film. Another quotation:

It is an astounding example of why well-meaning but basically clueless fanboys should never, ever be allowed to make technical or artistic decisions regarding the presentation of their favorite movies. The disc is, simply put, an atrocity. Every single decision regarding the video transfer is completely wrongheaded. I hardly know where to begin.

One of the reviewer's points is that it never should have been encoded as 16:9 with giant pillarbars as it loses resolution as compared to a 4:3 encoding with small letterboxing. Anyway, he also confirms the people making the DVD used the original ~1.40 sources. Another of his points is that what was drawn (as shown in this DVD) was not how it was intended to be viewed. So, what you're aiming for and how you get to it is determined by what format you're going for. DVD, MKV, what? The reviewer also says NTSC elements were used as the source, and then converted to PAL. I suspect it's a field-blended mess but we'd need a sample from the DVD to confirm.

I added the 4:3 blue-border myself, so it may not be accurate.

For the second time, you added a 1.25:1 (or 5:4) border and it doesn't represent what would be shown in a 4:3 encode of the film for DVD. 720/576=1.25.

[bergqvistjl]

Thanks for that. There are various DVDs of TFTM out, all with seemingly unique transfers. And they all vary in proportions & ratios

Did you not read what he wrote? Or understand it? The full review from which he quoted is here:

http://www.dvdtalk.com/reviews/18370/transformers-the-movie-reconstructed/

The review is of the R2 British 'reconstructed' version of the film. Another quotation:

It is an astounding example of why well-meaning but basically clueless fanboys should never, ever be allowed to make technical or artistic decisions regarding the presentation of their favorite movies. The disc is, simply put, an atrocity. Every single decision regarding the video transfer is completely wrongheaded. I hardly know where to begin.

One of the reviewer's points is that it never should have been encoded as 16:9 with giant pillarbars as it loses resolution as compared to a 4:3 encoding with small letterboxing. Anyway, he also confirms the people making the DVD used the original ~1.40 sources. Another of his points is that what was drawn (as shown in this DVD) was not how it was intended to be viewed. So, what you're aiming for and how you get to it is determined by what format you're going for. DVD, MKV, what? The reviewer also says NTSC elements were used as the source, and then converted to PAL. I suspect it's a field-blended mess but we'd need a sample from the DVD to confirm.

I added the 4:3 blue-border myself, so it may not be accurate.

For the second time, you added a 1.25:1 (or 5:4) border and it doesn't represent what would be shown in a 4:3 encode of the film for DVD. 720/576=1.25.

So why do all my 4:3 DVDs have a PAL resolution of 720x576 and not 768x576? Unless their not actually in 4:3 of course, but I thought it was either 4:3 or 16:9 for DVDs?

If I run FFMPEG on my (native) 4:3 PAL source, I get the following:
"Stream #0:1[0x1e0]: Video: mpeg2video (Main), yuv420p(tv, bt470bg), 720x576 [SAR 16:15 DAR 4:3], max. 8000 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc"

It's not anamorphic so surley my player won't stretch it to 1024x576 (16:9) so surely it should just display it as is?

Where are you getting 768 as the width for the 4:3 image from?

I had assumed that if it was a non-anamorphic 4:3 DVD, it would display it as it is, but if you had an anamorphic DVD, it would stretch the image out to 16:9 (1024x768).
Are you saying that it's also stretched slightly even if it's 4:3?

[smrpix]

Are you saying that it's also stretched slightly even if it's 4:3?

Both 16:9 and 4:3 DVDs use non-square pixels and are stretched.

Again the question is what is your final goal? Theatrically it would appear something like this:

[manono]

So why do all my 4:3 DVDs have a PAL resolution of 720x576 and not 768x576?

Geez. Because they are stored on the DVD as 720x576 and stretched to some 1.78:1 ratio such as 1024 x 576 for 16:9 PAL DVD playback, and some 1.33:1 ratio such as 768x576 for 4:3 PAL DVD playback. That's what the Display Aspect Ratio (DAR) is all about. It's kind of basic stuff. Here, read this:

http://www.doom9.org/aspectratios.htm

It's not anamorphic so surley my player won't stretch it to 1024x576 (16:9) so surely it should just display it as is?

Nope.

Are you saying that it's also stretched slightly even if it's 4:3?

Yep.

[bergqvistjl]

Are you saying that it's also stretched slightly even if it's 4:3?

Both 16:9 and 4:3 DVDs use non-square pixels and are stretched.

Again the question is what is your final goal? Theatrically it would appear something like this:

My bad, i'd assumed that only 16:9 DVDs were stretched. Well you learn something new every day

So let me get this straight, for a PAL DVD you get the following:
Watching 4:3 video on a 4:3 display - The video is stored on disc at 720x576, and your player stretches it horizontally to 768x576.
Watching 16:9 video on a 16:9 display - The video is stored on disc at 720x576, and your player stretches it horizontally to 1024x576.

and for an NTSC dvd:
Watching 4:3 video on a 4:3 display - The video is stored on disc at 720x480, and your player stretches it to 720x540 (so in this case it's altering the vertical only - not the horizontal as PAL does? This is what VLC is doing anyway)
Watching 16:9 video on a 16:9 display - The video is stored on disc at 720x576, and your player stretches it to 720x405 (Again, for NTSC, VLC is altering vertical instead of horizontal)?

My goal was basically to work out what the ratio of the animation frame was, but I think that's hampered by the fact that it looks to me like even the 'reconstructed' version, for that shot at least, has been stretched incorrectly anyway (comparing it with the US 4:3 one).

See here: 16:9 image simply cropped to 4:3 vs taking 4:3 image, removing black bars then expanding remaining image back to 4:3

I took the source (not correting for anamorphic, so it was in its original squeezed 768x576), removed the black bars, then stretched out the image horiontally to 768x576 again, and it aligns pretty well with the much more accurate NTSC one (blown up to 768x576).

[jagabo]

So let me get this straight, for a PAL DVD you get the following:
Watching 4:3 video on a 4:3 display - The video is stored on disc at 720x576, and your player stretches it horizontally to 768x576.
Watching 16:9 video on a 16:9 display - The video is stored on disc at 720x576, and your player stretches it horizontally to 1024x576.

and for an NTSC dvd:
Watching 4:3 video on a 4:3 display - The video is stored on disc at 720x480, and your player stretches it to 720x540 (so in this case it's altering the vertical only - not the horizontal as PAL does? This is what VLC is doing anyway)
Watching 16:9 video on a 16:9 display - The video is stored on disc at 720x576, and your player stretches it to 720x405 (Again, for NTSC, VLC is altering vertical instead of horizontal)?

With analog SD output NTSC picture remains 480 lines tall but the width is essentially squished to the equivalent of 640x480 in the analog domain.

On an upscaling player the size to which the video is scaled depends on the size of the output frame. For 4:3 DAR DVDs the full frame is upscaled to the height of the output and pillarbox bars are added to fill out the frame. So 4:3 DAR DVD (both NTSC and PAL) will be upscaled to 1440x1080 and 240 pixel wide pillarbox bars added to fill out a 1920x1080 frame. Or for 1280x720 the DVD is upscaled to 960x720 and pillarbox bars added. With 16:9 DVDs the frame is scaled directly to the final output size, 1920x1080 or 1280x720.

[manono]

My goal was basically to work out what the ratio of the animation frame was, but I think that's hampered by the fact that it looks to me like even the 'reconstructed' version, for that shot at least, has been stretched incorrectly anyway (comparing it with the US 4:3 one).

Apparently, the real aspect ratio is 1.4:1. And it's correct, even though it was never intended to be viewed at that aspect ratio. For that and for other reasons as discussed in the DVDTalk review linked above, this is probably the worst DVD ever made of that film.

[pandy]

Perhaps you can search for frame with circle - it should be easy to find proper aspect ratio with circle.

But how do I know if i'm looking at what's supposed to be a circle or not?

I assumed you have well trained neural network between ears.