Jump to content

Question about mkv aspect ratio


thrillcat

Recommended Posts

thrillcat

In Emby, the aspect ratio seems to be simply representing the resolution aspect ratio instead of the actual film's ratio.

 

Example: Apocalypse Now UHD is listed as 3840x2160 resolution, and 16:9 Aspect Ratio. However, if you go to IMDB and view the actual aspect ratio (or play the film), it's correctly reported as 2.39:1.

 

For those of us with projectors and masking systems, having this information right there on the movie's title page is really nice, but it doesn't seem accurate.

 

Could that information be pulled from IMDB instead of the file resolution?

 

One step further, it would be REALLY cool if the aspect ratio could be added at the top of the movie page with the length and rating, etc. information. Perhaps have several fields the user could choose up to X number to display at the top. I love the "ends at" item, and the rating, viewer rating, etc., but could do without date added, etc. up there, and would prefer a couple other options.

 

Thanks!

Link to comment
Share on other sites

Happy2Play

Sorry no information can come directly from IMDB do to the fact they do not have a free api.

 

Every source/encode could be different so simply applying a arbitrary values I think would cause just as many problem.

 

Date Added isn't going anywhere, lots of posts about it being gone right now in 4.3.  It will be back in 4.4.

Edited by Happy2Play
Link to comment
Share on other sites

thrillcat

Again, a choice would be nice. Alllow each user to turn off or turn on up to, say 5 metadata items to include in that space.

 

But back to aspect ratio, is there another database that could provide accurate info on AR?

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

Happy2Play

My question would be why is it not showing the correct AR?  Personally I would expect the media to be correct over any database.

Link to comment
Share on other sites

thrillcat

I don’t know.

 

This is an MKV rip of the new Rambo.

 

310ef49b87951b3c4e3efcc75bb29687.jpg

 

This is the actual file playing.

 

a52fc77dfd8e9a4603fc6d74d2e01fcd.jpg

 

Definitely NOT 16:9. A quick sampling shows that every movie in my library reads as 16:9.

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

crusher11

My question would be why is it not showing the correct AR? Personally I would expect the media to be correct over any database.

Because Blu-Ray only supports 16:9, so movies of any other ratio have hard coded pillar or letter boxes.
Link to comment
Share on other sites

Happy2Play

Well all my Test media would appear to shows their proper AR.  So is this a encoding issue?

Link to comment
Share on other sites

Happy2Play

3840X2160 Is 16:9

 

3840x1608 is 2.39:1.

Edited by Happy2Play
Link to comment
Share on other sites

thrillcat

Well all my Test media would appear to shows their proper AR. So is this a encoding issue?

Straight bluray rips using makemkv, so I don’t know? PLEX shows the same incorrect data.

 

I’m not doing anything but rip, no transcoding.

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

The black padding is typically embedded into the video so that's why it would be different than what you see on Imdb.

Link to comment
Share on other sites

crusher11

Well all my Test media would appear to shows their proper AR.  So is this a encoding issue?

How are you getting your Test media?

 

Blu-ray and UHD only support 16:9, DVD only supports 4:3 and 16:9. The only way to get any other resolution is to re-encode and remove the black bars.

Link to comment
Share on other sites

sfatula

The only way to get any other resolution is to re-encode and remove the black bars.

 

Exactly. When I Handbrake mine, I get correct aspect ratio as Handbrake removes the black bars. 

Link to comment
Share on other sites

thrillcat

Exactly. When I Handbrake mine, I get correct aspect ratio as Handbrake removes the black bars.

So we must sacrifice quality to remove black bars.

 

Which leads me back around to my original question. Is there a different source which would provide accurate aspect ratio information for the film, not the file?

 

Blu-ray.com perhaps?

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

sfatula

So we must sacrifice quality to remove black bars.

 

 

 

I don't sacrifice any perceivable (by me) quality, but, I was in no way suggesting you must or should do this. I was merely agreeing with crusher11 by pointing out if you do remove them, the ratio is correct. You've already lost quality as bluray is compressed. 

Link to comment
Share on other sites

crusher11

That hypothetical original isn't relevant to anything, though, because it's unattainable. Compressing further to remove letter or pillarboxing is an entirely different matter.

  • Like 2
Link to comment
Share on other sites

sfatula

That hypothetical original isn't relevant to anything, though, because it's unattainable. Compressing further to remove letter or pillarboxing is an entirely different matter.

 

You're not zipping a zip file. You are more accurately re-compressing. It is decompressed, adjusted, and re-compressed. You don't need to shrink the file, up to you based on your settings. But UHD takes a long time to process anyway, and it's a hassle. I just disagree with the notion you are losing something, other than time. If you have not done it from your first rip, then, too much work I am sure. I have more than a thousand movies, but, have processed every one of them.

 

You can't get a movie aspect ratio from imdb or anywhere else, many movies come in different forms, for example IMAX versions which have their own aspect ratio. 

 

You could change the embedded title only and set the prefer embedded title option in Emby. This would allow you to put the aspect ratio in the title. 

 

But it's an interesting problem as I have a projector also and it is handy to know. 

 

Here's some posts from a while back related to this:

 

https://emby.media/community/index.php?/topic/23735-aspect-ratio-using-original-aspect-not-file-aspect/

Link to comment
Share on other sites

crusher11

It is decompressed, adjusted, and re-compressed. You don't need to shrink the file, up to you based on your settings.

This is entirely incorrect.

 

You can't "decompress" it. That would require magically inventing all the data that was compressed out of the image during the disc's authoring stage. You then compress it again after processing it, and you will lose quality relative to the original even if you output at exactly the same file size. That's how compression works.

  • Like 1
Link to comment
Share on other sites

sfatula

Semantics. So, you are saying the video a played as is? Hardly. The already compressed (encoded) frames have to be decoded (you might say decompressed) and assembled to form a complete frame to send to the video display, or, edited to remove the black bars, call it what you want. I was not saying you get the original video. Obviously you do not. You get the best approximation of the original video, just as you do when you play it. But believe as you wish! I've provided 2 solutions to the OP problem.

Edited by sfatula
  • Like 1
Link to comment
Share on other sites

sfatula

Everything you just said is wrong.

No idea what you are trying to say? You are offering a solution to the OP? It is not incorrect. And it most certainly is not incorrect to say I can remove the black bars and that "I see" no quality loss, which is what I said. You can imagine you see the loss if you wish. 

 

Read up, this says in more words what I am saying with less, which wasn't the point of course. The point is to address the OP not worry about other things that do not matter. 

 

https://www.vcodex.com/hevc-an-introduction-to-high-efficiency-coding/

 

A video decoder decompresses the bitstream to create a sequence of decoded frames.

 

A video decoder reverses the steps:

  • Entropy decoding and extracting the elements of the coded sequence
  • Rescaling and inverting the transform stage
  • Predicting each unit and adding the prediction to the output of the inverse transform
  • Reconstructing a decoded video image.
Link to comment
Share on other sites

thrillcat

No idea what you are trying to say? You are offering a solution to the OP? It is not incorrect. And it most certainly is not incorrect to say I can remove the black bars and that "I see" no quality loss, which is what I said. You can imagine you see the loss if you wish.

 

Read up, this says in more words what I am saying with less, which wasn't the point of course. The point is to address the OP not worry about other things that do not matter.

 

https://www.vcodex.com/hevc-an-introduction-to-high-efficiency-coding/

 

A video decoder decompresses the bitstream to create a sequence of decoded frames.

A video decoder reverses the steps:

  • Entropy decoding and extracting the elements of the coded sequence
  • Rescaling and inverting the transform stage
  • Predicting each unit and adding the prediction to the output of the inverse transform
  • Reconstructing a decoded video image.

Everything he said is accurate.

 

I do not plan on utilizing your “solution”, as it’s not a solution, it’s a compromise, and not one I’m willing to make, so your time may be better spent in other threads.

 

The only feasible “solution” to this issue is locating an open source database to use instead of the video file itself to pull the film’s aspect ratio information.

 

 

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

sfatula

The other solution I proposed is adjusting the movie title, it's a one time effort along with the change to Emby setting. That wouldn't work for you? Seems pretty simple. 

 

How do you otherwise propose to get around movies that come out in different formats (same movie) with different aspect ratios? Consider this page:

 

https://www.imdb.com/title/tt1477834/technical

Edited by sfatula
Link to comment
Share on other sites

Happy2Play

Basically you want original material and FAKE the AR to something the physical media technically is not.  

 

Emby probes the media, so 3840X2160 is 16:9.

  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...