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Full Version: Annoying dynamic contrast effect
OESF Portables Forum > Model Specific Forums > Gemini PDA > Gemini PDA - Linux OS
There seems to be some sort of dynamic contrast baked into the kernel/display, similar to what Intel GPUs do by default on laptops

See here: (it's not the camera)

It's particularly noticeable in the shade of black/grey on the LXQT menu button and clock when focusing and unfocusing a terminal window

Unless I'm mistaken this is Miravision, which seems to live in /drivers/misc/mediatek/video/common/color20, but I've had no luck disabling it via the obvious config flags (CONFIG_MTK_PQ_COLOR_MODE etc)

Has anyone else noticed this/tried to disable it?

Simply set this in the kernel config:


Nice increase in image quality with this change (things look closer to how they should), god only knows what mediatek were thinking with this
So it turns out disabling AAL breaks sleep (i.e. screen does not wake up when opening lid, everything else does)

Fortunately there is a simple fix - instead of disabling it in the kernel, add a cron to pause aal - it seems this usermode binary does all the heavy lifting. It autorestarts if killed, so pausing is the only option

killall -STOP /vendor/bin/aal
Hacked the above fix into repowerd to allow brightness control to still work, anyone interested can find it in this commit:
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