How can you tell aspect ratio of inserted Blu-Ray DVD?

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ikomrad
Posts: 17
Joined: Fri Feb 10, 2017 5:57 am

How can you tell aspect ratio of inserted Blu-Ray DVD?

Post by ikomrad »

Usually the top / labelled side of the BD has video with the 16:9 aspect ratio, but I ran into one that had 4:3 on the "top" side and 16:9 on the "bottom". I look all over the case, the disc, and the MKV details screen, but I did't see the aspect ratio anywhere. Is there a way to tell what aspect ratio each side is which using MakeMKV or another tool?

Thanks!


---Edited to replace "DVD" with "BD" and make the question clearer ---
Last edited by ikomrad on Wed Jun 21, 2017 3:52 am, edited 1 time in total.
Woodstock
Posts: 9914
Joined: Sun Jul 24, 2011 11:21 pm

Re: How can you tell aspect ratio of inserted Blu-Ray DVD?

Post by Woodstock »

"Blu-Ray DVD" is a conflicting term... You either have a DVD or a BD.

DVD's representation is 4:3, but there are ways to make it act like other aspect ratios. One is anamorphic, where the horizontal and vertical dimensions of a "pixel" are different, and the other is to letter-box the image, where the top and bottom of the picture area are black bars. Usually, there is a combination of these, to make 16:9. And where this information is stored can vary on the disk; it's supposed to be in two places (directory information and beginning of the video stream), but it may be in only one of them.

Typically, you will see "Wide Screen" on one side, if the disk is two-sided.

BD native is 16:9, but, like DVD, different aspect ratios can be crammed into it.
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