Okay, I’m having issues here. I downloaded the “Documentaries” BD25s from the spleen. When I mount and play any of the ISOs in VLC or MPC, it displays the correct 16:9 aspect ratio. But when MakeMKV rips them, the resulting MKVs are squished horizontally into what looks to be a 4:3 frame.

How do I correct this? I want to put them on my Plex server.

JEDIT: Ha! I figured it out, and the fix is easy. The “Video Display Width” header entry is incorrectly set to “720” in the MKVs. (The height is 720; the width should be 1280.) It’s probably also wrong in the ISOs.

Open the files in MKVToolNix GUI, and under Edit Headers just change the “Video Display Width” value to 1280 and then save it.

The threads that I googled on the subject seemed to say the headers were incorrect, and to fix it would require extracting the video stream, fixing the header and remuxing, but it turns out that’s not necessary.