Is 1.37 shorthand for 1.375 aspect ratio, or are they different?

[chronis]

Wikipedia (https://en.wikipedia.org/wiki/Academy_ratio) suggests that 1.37 AR is shorthand for 1.375: "The Academy ratio of 1.375:1 (abbreviated as 1.37:1)"
However, on another page in Wikipedia (https://en.wikipedia.org/wiki/Aspect_ratio_(image)), the two are listed separately.

So, are they in fact different or the same?

The reason I ask is because I have a film encoded in 4:3 AR that is listed on IMDB as having 1.37 AR and there is also an opening note in the film stating 1.37, so I need to know if the AR is indeed 1.37 or 1.375.

thanks

[Sharc]

Both may exist, but I don't know for sure. But why bother? The difference between 48:35 (1.37143) and 11:8 (1.375) is less than 0.3% or about 2 pixels height or width difference for a DVD. One won't notice this slight difference as a distorted picture.

[chronis]

Both may exist, but I don't know for sure. But why bother? The difference between 48:35 (1.37143) and 11:8 (1.375) is less than 0.3% or about 2 pixels height or width difference for a DVD. One won't notice this slight difference as a distorted picture.

Indeed, for practical purposes, it doesn't matter. Many people can't even detect distortions in 4:3 (1.333) when the correct DAR is 1.37. But I'm asking because if I'm going to set the DAR to 1.37 (when the original is incorrect), then I want to use the right numbers.

Surprised nobody in the forum has answered definitively yet. I hope it's not a stupid question :D

[Asmodian]

Not a stupid question, but one that would take a lot of work to answer correctly... and that may be impossible now.

Both have likely been used professionally, but that does not really say which is correct. Aspect ratio specs from the DVD era and before are not great or well followed. :(

I would follow Wikipedia's 1.375 if I was setting a value, it will become the standard as we get further away from that time period and their origin story makes sense. :)

Edit: 1.375 for film with sound, 1.37 for film without sound.

[Richard1485]

The reason I ask is because I have a film encoded in 4:3 AR that is listed on IMDB as having 1.37 AR and there is also an opening note in the film stating 1.37, so I need to know if the AR is indeed 1.37 or 1.375.


What do you mean "encoded in 4:3 AR"? Do you mean that the DAR is 4:3? If this video (about which we need some details) is a DVD, then it has to have a DAR of 4:3 or 16:9: those are the choices.

But I'm asking because if I'm going to set the DAR to 1.37 (when the original is incorrect), then I want to use the right numbers.

You can't determine the "right numbers" by looking on IMDb. 1.37:1 is so close to 1.33:1 that such films were often transferred to home video by slight cropping on the left and right. How do you know that that's not what happened to your video? Because if it did, by altering the DAR you'd be stretching the video on playback in a way that distorted it, because 4:3 is now the video's correct DAR, regardless of what the original AR might have been.

Does the note at the start state the film's original AR or make a statement about the video transfer? Even it's the latter, that's no guarantee that the figure is precise. The only way that you could justifiably correct the AR is if you compared your video to another source that you had strong reason to believe was right, discovered that it was squished/distorted somehow, and worked out an adjustment that would correct that distortion.

[chronis]

What do you mean "encoded in 4:3 AR"? Do you mean that the DAR is 4:3? If this video (about which we need some details) is a DVD, then it has to have a DAR of 4:3 or 16:9: those are the choices.

Sorry for not specifying the source. Actually, this is a 4k restored film from the 80s available for download rather than DVD. And yes, there is a note at the beginning that explicitly states that this film is shown in its original aspect ratio of "1.37:1", yet the DAR of the downloaded copy is 4:3. So I wanted to set the correct DAR in MKVtoolnix, which is simple.

I didn't really want to get bogged down in the details of this specific film. I just wanted to ask if 1.37 does indeed exist as an AR separate from 1.375. My assumption is that it does not since I have not seen a single source of information state as such. Everything I've read so far (outside of those Wikis) suggests that 1.37 is shorthand for 1.375.

[Sharc]

And yes, there is a note at the beginning that explicitly states that this film is shown in its original aspect ratio of "1.37:1", yet the DAR of the downloaded copy is 4:3. So I wanted to set the correct DAR in MKVtoolnix, which is simple.

I didn't really want to get bogged down in the details of this specific film. I just wanted to ask if 1.37 does indeed exist as an AR separate from 1.375. My assumption is that it does not since I have not seen a single source of information state as such. Everything I've read so far (outside of those Wikis) suggests that 1.37 is shorthand for 1.375.
When a native, uncropped 1.37(5) movie is dispalyed at 4:3 DAR then it will have small black borders top and bottom.
I have slight doubts with 1.37 being just a shorthand of 1.375. Shouldn't this be rather 1.38 then? :D
As has been said 1.37(5) originals have often been slighly cropped left and right for 4:3 DVD release and must be watched as 4:3, or the picture will be distorted. An example is the PAL DVD release of 'The Oxbow Incident' (original movie aspect ratio is 1.37(5)) which must be watched as 4:3.
So in your case the principal question is 4:3 (1.3333....) or 1.37(5). Only you can decide what you think is correct.

Edit: It seems that IMDB just uses the short form 1:37 for the 'Academy' ratio......

Edit2: A lot of formats are listed here:
https://en.wikipedia.org/wiki/List_of_motion_picture_film_formats
The Academy format is 1.375 as expected, but many other formats are specified as 1.37, so both seem to exist.

[Richard1485]

I didn't really want to get bogged down in the details of this specific film.

What is needed is details about the video, not this specific film. You don't seem to be distinguishing between the two. If a novel was written in France, that doesn't mean my copy shouldn't have "printed in Australia" on it.

And yes, there is a note at the beginning that explicitly states that this film is shown in its original aspect ratio of "1.37:1", yet the DAR of the downloaded copy is 4:3. So I wanted to set the correct DAR in MKVtoolnix, which is simple.

It is simple to set, but you don't seem to understand what it is. The film can be presented in 1.37:1 and still have a DAR of 4:3. Remember all of those letterboxed (not pan and scan) early DVDs of films that had ARs of 2.35:1, 1.85:1, 1.66:1, etc? They had DARs of 4:3 as well. The DAR is just a flag in the video stream that tells the video what shape to take on upon playback. This page (https://www.animemusicvideos.org/guides/avtech3/theory-videoaspectratios.html) illustrates what DAR is reasonably well.

Despite the note, it's possible that your copy has borders or has been cropped or has been stretched. (To rule out the first possibility, you'd need to decode the video properly, not just take a screenshot, and examine a frame.) While it's possible that the DAR of your copy is wrong, nothing that you've presented so far demonstrates that.

[chronis]

The video is not letterboxed and as I mentioned before, this is not a DVD release. It's a 4k restored film, available online. And yes, I know the difference between SAR and DAR, otherwise, I wouldn't be using terms like DAR. I understand and appreciate that you're all trying to help me determine whether 4:3 is the correct DAR, but this simply wasn't my question. (The image looks squished, so I'm 99% sure it's incorrect.)

The question was whether or not 1.37 exists as a separate standard from 1.375 (Academy ratio). So far, nobody has cited any evidence that they are distinct, aside from than the Wiki article from my first post. So this topic shall remain open in case anyone has something to add related to this general question.

[Sharc]

The question was whether or not 1.37 exists as a separate standard from 1.375 (Academy ratio). So far, nobody has cited any evidence that they are distinct, aside from than the Wiki article from my first post. So this topic shall remain open in case anyone has something to add related to this general question.
How about my Edit 2 in post #7?

[chronis]

How about my Edit 2 in post #7?

Edit: OK, I see that this is a different link from the one I provided earlier, and indeed it suggests that the 1.375 and 1.37 formats/standards are different. Thanks

[Old reply: It's the same link I provided in my original post and which led to my question. It lists them separately but are they really separate standards? It could just be a mistake.]

[SeeMoreDigital]

What is the film called?

[Richard1485]

The video is not letterboxed and as I mentioned before, this is not a DVD release. It's a 4k restored film, available online.

This has nothing to do with whether or not your release is a DVD. The examples that I gave above were meant to show the difference between the original AR of a film and the correct DAR for a video.

And yes, I know the difference between SAR and DAR, otherwise, I wouldn't be using terms like DAR.

It's not uncommon for people to use terms without fully understanding what they mean. Given that you responded to the examples that I gave above by reiterating that your film is not a DVD, it's fairly obvious that you didn't grasp the point that I was making.
I understand and appreciate that you're all trying to help me determine whether 4:3 is the correct DAR, but this simply wasn't my question.

I understood the question from the outset, but the question is predicated on the notion that the DAR of a video should match the original AR of a film:
The reason I ask is because I have a film encoded in 4:3 AR that is listed on IMDB as having 1.37 AR and there is also an opening note in the film stating 1.37, so I need to know if the AR is indeed 1.37 or 1.375.

But I'm asking because if I'm going to set the DAR to 1.37 (when the original is incorrect), then I want to use the right numbers.


That's false reasoning and a misunderstanding of DAR. But good luck finding an answer to your question about 1.37 versus 1.375.

[chronis]

@Richard1485 With all due respect, it sounds to me like you're much more interested in lecturing people and showing off your superior knowledge about DVD standards than providing relevant information. My question was not predicated on anything. I simply explained why I am asking the question, but I could have just as easily left out what I'm trying to accomplish, and the question could still stand on its own. I could have stated, for example, that I'm writing a paper on aspect ratios for film class and would like to know whether the two standards 1.37 and 1.375 (Academy ratio) were the same. I agree that this forum would be the wrong place to ask.

I am satisfied with the link that @Sharc provided, showing that the 1.37 and 1.375 formats clearly had different names and specifications.

[Richard1485]

@Richard1485 With all due respect, it sounds to me like you're much more interested in lecturing people and showing off your superior knowledge about DVD standards than providing relevant information.

In that case, you've completely misunderstood. Have a nice day.

[SeeMoreDigital]

Hmmm... What's the film called?