When is a 4K movie not a 4K movie?

So the other day, I was playing a new 4K movie (The Three musketeers - d’Artagnan), and noticed it’s not playing in 4K on my TV, it’s actually playing in FullHD (1080p).

When I opened the technical details, I noticed the actual width is smaller than 3840, it’s only 3824. Which seems to be forcing playback to 1080p.

I found a couple of other similar movies, that for whatever reason ended up slightly under the 3840 pixel width. All these files play in 1080p.

I can force these to play in 4K, but I have to set my UI resolution to 4K. Doing that unfortunately slows the UI down, and prevents me from playing 3D movies. As soon as I start a 3D movie (SBS, HSBS, HTAB or even MVC), the screen goes blank, and eventually I get a “signal lost” message from the TV. pressing stop on the remote, eventually stops playback and restores the video signal.

So how can I playback these movies that are not exactly 3840 pixels wide in 4K? I don’t want to have to re-encode them.

This is a known issue that is on the list of things to fix. I would recommend setting your UI back to 1080p and then make a manual whitelist. With this whitelist on the occasion where this comes up you can go into the video settings during playback and switch the resolution to 4K. More information about whitelists can be found in the following thread…

So I used the whitelist. I added 1920x1080 @ 23.98, 24 and 60Hz (2D & 3D), and also added 3840x2160 @ 23.98, 24 and 60Hz (2D only). I set the UI resolution to 1920x1080 (2D), and it seems to work now. All 3D movies I tested (SBS, TAB and FP) seem to work OK, and also normal 1080p movies and 4K movies. 4K including those slightly undersized ones now play in 4K.

Thank you.


One of the main reasons for setting up a whitelist is that, once you have, this works automatically - you don’t need to manually change resolutions.

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