J

Johnathon

Was temporal dithering (known as "surface dithering" in the Android system) disabled in your fork of Android 13 to prevent the additional subpixel flicker that affects newer Android devices?

If not, y'all need persist.sys.use_dithering=0 in your build.prop to disable it

Temporal dithering is when display drivers, usually by default, are configured to flash between two similar colors over and over again to try to approximate an "in-between color" in order to fake "smoother" color transitions in photos, gradients, transparency, and shadow effects, in addition to inducing flicker and "shimmer" on the grayscale edges of pretty much all antialiased text (because of the many shades of gray present at edges of text).

Temporal dithering can exist in different forms both at the GPU/OS level (the aforementioned "surface dithering" Android feature) — and at the LCD panel level (known as FRC/Frame Rate Control)

This unfortunate tactic is used on pretty much all modern iOS and Mac devices, and most importantly, I'm pretty sure is also the display driver default on recent Android versions such as 13.

For example, my PWM-free iPhone SE 2 still has extremely annoying temporal dithering flicker to my eyes when looking at a static page, compared to my old iPhone 6 that appears much more comfortable, still, and honestly more beautiful. I also own an iPhone 5 with iOS 6 that appears entirely still.

Because of this pixel-level flicker, the SE 2 is not a comfortable device to use despite not showing obvious backlight flicker on a slow motion camera.

E-ink devices are usually immune to this as they simply don't refresh when a static page is being displayed, but given that your display is a 60fps RLCD, it's extremely important that this additional source of pixel flicker is verified not to be present in your version of Android.

For me and many other members of this forum, devices that utilize heavy temporal dithering — even with a PWM-free backlight — can sometimes cause just as much (or more) eye strain and reading difficulties as devices that use PWM dimming.

Let me know if your team has already been aware of this

Thought I was the almost the only one with eye strain, but then I found this forum. Man, have I tried a lot of smartphones. I'm using a Nokia 7.2 right now, which is almost problem free. Unfortunately the speaker is very poor, so I've been eyeing an upgrade ever since. May it be of use to some, these are "some" of the smartphones I've tried:

• Samsung A32 5G - absolutely horrible.
• Samsung A52 5G - thought I'd shelve out some extra cash in hope for a better screen, it was slightly better than the A32 5G, but still terrible.
• OnePlus Nord - about the same as the A52 5G. Then went online to found many more had problems with OLED, so no more OLED for me. Unfortunately, there are not a lot of LCD phones left. But next ones would surely be LCD and preferably without PWM.
• Motorola G Stylus (the OG one) - very pleasant on the eyes and not too big. Would've kept it but the performance was very bad, almost everything lagged and stuttered.
• Xiaomi Redmi Note 9 Pro - acceptable on the eyes but kept killing my apps.
• Motorola Moto G 5G Plus - acceptable screen but very buggy in use, many crashes and reboots.
• Samsung A22 5G - good above 25%, but I use smartphone mostly at night, and 25% is too much brightness.
• Poco X3 NFC - not good, could only use it for a few minutes.
• Poco X3 Pro - same as NFC, slightly better colors but that was it.
• Nokia X20 - very pleasant screen, but when it updated to latest version it bootlooped…
• Poco M4 Pro - PWM free (also checked myself with camera) but very unpleasant on the eyes, not sure if it's the coating or the rendering, but unacceptable.
• Motorola Moto g100 - NOT PWM free unlike said on notebookcheck, below ~70% it absolutely has PWM. I don't want to run at 70% minimum or with overlays that prevent bank apps from running.
• Motorola Moto g60s - a keeper so far, still testing but no PWM detected on my 4GB variant. 6GB wasn't in stock here but I have the 6GB in order, which hopefully arrives at the end of next week.
• Motorola Moto g200 - also good, no PWM detected. 10g lighter than the g60s, but the camera is worse, despite having 128MP vs 64MP. gcam also only results in blurry pictures. Not worth the 2x price increase over the g60s, so I'm returning it.
• Fairphone 4 - no PWM and so far so good on the eye. Camera is really good with gcam, stock camera is quite poor. Much better camera than the g60s. It does weigh a lot (225g) and is quite expensive at double the price of the g60s. I do like their update policy of at least 5 years, whereas the Motorola only has 2 years of upgrades, so TCO will be about the same.

So, hopefully someone can use this information. Thought I'd share it with people with the same problem.

Update: The moto g60s 6GB is also PWM free.

Update 2: After more testing the g60s I find it not as comfortable as my Nokia 7.2 and will be returning it. Maybe I'll try the X20 one more time and otherwise I'll go for the Fairphone 4.