Postby kmf31 » 02 Jul 2016 18:36
I observed the same problem (with vlc-2.2.2 on Ubuntu 16.04) on a laptop with internal screen of resolution 2560x1440. I don't know if this is a general vlc problem (for the branch 2.2.x) on Linux or only for this particular binary build on Ubuntu 16.04.
My solution/workaround: reduce artificially the resolution from 2560x1440 to 1920x1080 or even to 1280x720. This has also the advantage to have more reasonable size icons and other applications/fonts ...
Normally one should use for the Xorg driver the same resolution as the natural resolution of the monitor for best quality but on a small laptop screen 1920x1080 (with 2560x1440 natural resolution) is actually not so bad and for 1280x720 one has exactly 2x2 physical pixels for one logical pixel of the Xorg driver such that there are no artifacts (but indeed a reduction for HD movies which seems however of limited importance to me for a very small screen).
In Ubuntu the logical resolution is easily changed in the "Display" application.
If you have a 4K monitor the corresponding limitation to 1920x1080 should also work very nicely (also 2x2 physical pixels = 1 logical pixel) and also be better for other Ubuntu applications unless you have a screen of more than a 1 meter of size and 50 cm in front of your eyes ... Otherwise, with a bit more distance than that your eyes are physically unable to distinguish individual 4 K pixels (which correspond to an angle ~ 1 arc minute = 1/60 degree or less which is viewed as a perfect point by the human eye, i.e. the human eye can not distinguish two neighbor pixels). If you are sufficiently close to the 4K screen such that the eye can distinguish two neighbor (4K) pixels than the global angle of the screen is about 60-70 degrees which is too much for the brain to proceed it as "one" image, i.e. without concentrating on parts/sub-images.
This is by the way the fundamental problem of 4K anyhow ...
