[Android General] Woke World:
Hello XDA, I've recently purchased an Android 9 device and like so many others, I've found the new Android 9.0 Intelligent Adaptive Brightness to be a massive headache when it's turned Off and manually adjusted below [50%] brightness.

I have tried for Literally months to track down the cause of this issue on so many various handsets and CPU manufacturing companies.

To begin with, it seemed like this was not a Device Dependent problem, but a problem with Android 9's Changes into Artificial Intelligence for Brightness Control - Mostly because it was a problem being found across-the-board..

How could it be a device problem and not a Firmware problem ?

It seemed very convincing that the cause was Android 9 because people have multiple reports online of this happening after updating the firmware, but not previously happening on any Prior Firmware.

After a while, I remembered having this problem Years Ago, When Android Devices did not have a Hardware Light Sensor - "Luckily I remembered what the cause was back then, it was called Content Aware Backlight"

The idea was that the Phone or Tablet doesn't need a Light Sensor, it can adjust the screen based on Content.

However, this feature provided to be More Problematic than Useful in Android 2.3 days, so they Removed the feature in Further builds up to Android 8.1

After Android 8.1 these features have enabled again to target Battery Consumption.

The Adaptive Brightness features are enabled permanently to enhance the Adaptive Battery AI.

Remember that these are not Simple A.i ... These are Advanced Neural Networks.

So enough with the background, here's the Juice.

Let's look at a Qualcomm CPU Device,

• Qualcomm

A Qualcomm Android uses a brightness feature called CABL "Content Aware Backlight", this feature is Fighting with Android 9's Adaptive Brightness feature and causes a Flickering Effect for the lack of a better word.

What About Others like MTK & Intel ?

• Intel

An intel device also has a built-in feature that fights with Androids Adaptive Brightness, called "Intelligent Backlight Control"

• MediaTek

MediaTek CPU's also have a feature called AAL "Advanced Adaptive Lighting"

To disable these features, is to make your Firmware Android 9.0 Compatible.

DISABLING GUIDES AND TIPS,

UNKNOWN DEVICE GUIDE,

Today I found out how to solve. I had to edit a file located in /persist/sensors/registry/registry. If you have root access you have to edit the file tcs3701_platform.als.fac_cal so that it looks like that:

{"tcs3701_platform.als.fac_cal":{"owner":"sns_tcs3 701","scale":{"type":"flt","ver":"1","data":"0.905 537"},"bias":{"type":"flt","ver":"0","data":"0.000 000"}}}

If you aren't able to acces that file you can go to TWRP, copy it to internal storage, modify it with a text editor, go back to recovery and restore the file.

Before touching anything a persist partition backup is highly recommended.

GENERIC DEVICE DISABLE,

You've certainly noticed that when you're outside the screen brightness goes at max level and contrast is over saturated.

It comes from adaptive display, personally I don't like that so I've found a way to disable it in build.prop

Open build.prop and edit this:

ro.vendor.display.ad=1

Change value to 0, save and reboot

NO ROOT ?

People have reported that Disabling or Clearing Data for "Device Health Services" in Settings > Apps helps significantly... however I did not have improvements myself.

QUALCOMM

Seems that this service controls black vibrance and overall screen sharpness. In lg g2 forum i ve read that this is the dynamic screen contrast. I ve added those line in my build prop, changed everything to 0, but i cant notice any difference.

ro.qualcomm.cabl=1
hw.cabl.level=Auto
persist.qcom.cabl.video_only=1

If disabling this in Build.prop doesn't work, or you would like to try disable without ROOT ACCESS ..

• Open Settings

• Open Apps

• Open Content Aware Backlight App

• Select DISABLE to disable the Application

ROOT ?

• Try a removal of the APK File that handles Content Aware Backlight in Either System/App or System/Priv-App

More for G2 - https://xdaforums.com/showthread.php?t=2466268

MEDIATEK CPU & AAL

I have tried multiple AAL Disabling methods in Build.prop and nothing works.

The only Sure-fire way to Remove or Disable it is by Removing the AAL Binary File

system/system/bin/aal

on my device, system is actually a subdirectory of system - so I write system/system/ as an example. Your device may use

system/bin/aal

And disable using build.prop Props,

ro.vendor.mtk_aal_support=0
persist.vendor.sys.mtk_app_aal_support=0

I'm still looking for Samsung and Speadtrum Props.

Please remember that this is a common issue found on everything... Personal Computers, Smartphones and T.V's.

I've found reports online for both Intel's Intelligent Backlight in products like T.V's, Laptops, Desktops, Smartphones.

The same goes for CABC, CABC is the most notorious for both Android and PC User's, Dominating the Google Search Results for Adaptive Brightness Issues.

CABC or Content Aware Brightness Control, is an absolutely disgusting design that they should have fired someone over a long time ago... The feature has reported up to 15% battery consumption improvement, however user's have reported up to 100% of headaches from viewing the screen are attributed to uncontrollable brightness and flickering - especially while gaming.

A PC Guys Write-up,

http://www.anandtech.com/show/8983/dell-xps-13-review/5