Seemingly Duplicate Resolutions In Set Resolution Menu by default on Intel

[khalidabuhakmeh]

👋 Hello,

I'm a BetterDisplay Pro user, and I love the product.

I noticed that I see duplicate resolutions when I go to the Set Resolution menu. Please take a look at the image below.

I also included the About page here.

[waydabber]

Hmm. Indeed. This is not how it should work. Can you enable these and create a screenshot? That should give a bit more info about these resolutions that would be helpful for me. Thank you!

[waydabber]

No worries, I was able to reproduce the issue on my Intel test machine! Thanks for reporting!

[waydabber]

All right, fixed it, will be in the next resase. The problem was the multiple bit-depth options on Intel which caused a duplication.

Sorry about this!

[khalidabuhakmeh]

No worries. I love this product. I am happy you found the issue and that I could help. Keep up the great work.

[waydabber]

I'll just keep this one open until I release the updated version so I don't forget to include it in the release notes. :)

[joevt]

The bit depth in a CGDisplayMode refers to the frame buffer bit depth (where you can switch between 8 and 10bpc). Note that the two modes (with different mode index) both have the same modeID. The modeID points to a DetailedTimingInformation structure (found in ioreg) that describes the actual timing and the output color encoding and bit depth (for modern GPUs). The frame buffer bit depth and the output color encoding and bit depth don't need to match (and of course at least one of the frame buffer bit depth values won't match). The frame buffer is usually RGB but the output may be YCbCr (like for HDMI displays).

[waydabber]

Yes, the app handles the differing frame buffer bit depths (there is a 'Color Depth' submenu for that on Intel), the duplication of resolutions due to this in the 'Set Resolution' menu was an oversight on my part as I mostly test my app on Apple Silicon where only a single framebuffer bit depth is offered in practice - at least I never saw anything else (normally the Set Resolution menu should list resolution alternatives only for the current bit depth and refresh rate - except if it is set to show everything under Settings/App Menu, but then it properly lists bit depth differences in the list as well).

BD currently does not detect or differentiate at all based on output color encoding - neither on Intel (where it would be technically possible), nor on Apple Silicon (where the method is unknown, but see the other post on how one could probably get that info as part of a more proper link description which should probably match in content with the LinkDescription key in the windowserver display config, but it's just a guess, did not go after it yet).