Develop Bugs

Screen brigthness, negative value?

This is a two part question. What screen brightness do you usually leave your phone at? I leave mine on what seems to be 0 (see next paragraph for explanation) and my screen still always uses around 60-70% of my battery. I don't understand how it can use that much without the backlight on.
Next question - When adjusting the screen brightness and the slider is all the way to the left is that 0? I'm asking because every widget out there when set to 0 is a a few times brighter than when I manually move the slider all the way to the left. Also, after using a widget to toggle to 0 and I check in the display settings, the slider isn't all the way to the left.
So I'm wondering what is true 0? What the widgets set it to or with the slider all the way to the left? Could the slider being all the way to the left actually be hurting my battery life?

No zero on the slider is technically not zero. You can confirm this checking your brightness sysfs file. You have to decompile framework and adjust some numbers. We can take it down to true zero or slightly above which would be much dimmer.
I did this for the atrix. Im surprised it hasnt been done yet for the nexus.

I know it is not actually 0 because if it was I wouldn't be able to see anything on the screen.
Is there anyone that has insight on my questions though?

I dont understand your question. Zero is not true zero unless we mod the framework. So your backlight is not "off". I dont know why youre getting so much drain.
But we should mod this anyway. Use root explorer and go to sys/devices/omapdss/display0/a6e8aa0 and open the brightnesd file. Note that value with your slider at zero and you will see a reading of 30 (0-255). So we can lower that down to maybe 5-10 and zero on the slider will be much dimmer = battery saving.

I have a similar problem. The max brightness is piercing and the min brightness is just a tiny bit too dim.
I have tried used root explorer to change the maximum brightness from 255 to 100 hoping that the slider may be more granular after. For some reason however I cannot update the max brightness file. I have ensured that it is r/w mounted and tried changing the permissions too. It says that the changes have been made and the original backed up. When I reopen the file it hasn't changed.
BTW, my 'brightness' file is at 10 when placed at the minimum brightness.

Try the newest AOKP.
Brightness controls.
I actually have NEVER used auto brightness...even back in my OG days.
And my X days.
Even when custom auto-brightness options were around I ignored them.
I'd simply keep it at around %20 of the default lowest value.
BUT...this is slightly annoying when you step into the sun and can't see anything.
With the newest AOKP you can even set the amount of brightness changes.
I set up four values.
I've mine set up for a pitch black room to lowest.
Average room to my previous 20%ish.
Bright (sunny) to 100/255
SUPER sunny to 240/255.
I didn't notice any added drain today.
But this was my first test.
I think this feature was actually kanged from CM9, but I'm not certain.

So far I have resisted the temptation to get flash happy and I am on stock 4.0.2 but rooted. Do I have any options without changing ROM?

aidanbree said:
I have a similar problem. The max brightness is piercing and the min brightness is just a tiny bit too dim.
I have tried used root explorer to change the maximum brightness from 255 to 100 hoping that the slider may be more granular after. For some reason however I cannot update the max brightness file. I have ensured that it is r/w mounted and tried changing the permissions too. It says that the changes have been made and the original backed up. When I reopen the file it hasn't changed.
BTW, my 'brightness' file is at 10 when placed at the minimum brightness.
Click to expand...
Click to collapse
We cant change that brightness file with root explorer, even mounted, unless we mod the driver first. It will likely just revert right back to its previous value.
However it is possible i bet to edit the driver. Would be a cool project. You could also try to echo your desired value in terminal. ie echo 255 > brightness. But you prob will get the same result as using root explorer.
Maybe ill look at the driver with my limited skills heh. Or the alternative is to mod the framework which is def possible to fix this, and easier. We did exactly this on the atrix. And the sgs2 had it done too.
Edit: i think i found the code for your granular request. Check lines 30 or so.
https://github.com/ogdobber/android...0/include/linux/platform_data/panel-s6e8aa0.h
Still would be easier to do in framework instead.

How to dim the GN screen even more?

I find the dimmest screen toggle still too bright. I find it embarrassing to use in dark public spaces.
Is there a way to dim the screen even more?

Download the screen filter app from the play store. Literally puts a filter effect on the screen to make it appear darker making it much easier to use in the dark.

Yes its possible to take the screen much lower, but we have to edit the framework. Nobody had done this mod yet for some reason.

CM9 has the ability to change the screen lowest settings built in

B97 said:
Download the screen filter app from the play store. Literally puts a filter effect on the screen to make it appear darker making it much easier to use in the dark.
Click to expand...
Click to collapse
+1. I use Screen Filter also, it's uber handy for reading at night when the light seems too bright. If you've got hardkeys like I had on my Desire, you can even turn them off.

i wrote a tutorial on how you can mod the frameworks apk. it's very easy and you can change the brightness levels to anything you want. here's the thread
screen filter only puts a transparent layer on the screen and messes with the colors. modding the frameworks will lower default brightness to any level you want. you can raise it too if you like.

Thanks for all the ideas. I went with the easiest one, Screen Filter.

AOKP also has an option to reduce screen brightness...

dynamicpda said:
Thanks for all the ideas. I went with the easiest one, Screen Filter.
Click to expand...
Click to collapse
Good man!
Sent from my GT-I9100 using XDA

neotekz said:
i wrote a tutorial on how you can mod the frameworks apk. it's very easy and you can change the brightness levels to anything you want. here's the thread
screen filter only puts a transparent layer on the screen and messes with the colors. modding the frameworks will lower default brightness to any level you want. you can raise it too if you like.
Click to expand...
Click to collapse
Great work, I've been wondering why nobody did this mod yet for the nexus. I made that same mod on my atrix, using the sgs2 thread as well. But I've been too lazy to do it for nexus.
The above mod is the best option. Screen filter doesn't achieve the same results. The above mod reduces power draw as well when on the lower brightness setting of 5 or so. Screen filter just hides the higher brightness but has same power draw.

RogerPodacter said:
Great work, I've been wondering why nobody did this mod yet for the nexus. I made that same mod on my atrix, using the sgs2 thread as well. But I've been too lazy to do it for nexus.
The above mod is the best option. Screen filter doesn't achieve the same results. The above mod reduces power draw as well when on the lower brightness setting of 5 or so. Screen filter just hides the higher brightness but has same power draw.
Click to expand...
Click to collapse
That would be correct for back-lit screens. For the Galaxy Nexus screen, though, Screen Filter does help reducing power draw as a darker screen content = lower brightness.
I used to use SF for quite a while until I got fed up of it causing stutters to most animations. After thorough examination I concluded that the Nexus's GPU is the culprit. For some reason it just doesn't like multiple graphics being updated at once. Modding the overlay XML allows it to run at full speed.
Can anyone confirm the same reduced framerate issue?. It's also the reason why some ROMs include a setting to remove the navigation buttons glow. I tested with CM9 on the SGS2 and experienced none of the stutters in cases where the GN would. Another example: sliding between sections (comments, ralated, etc.) in YouTube is laggy iff the video is playing.

fnf said:
That would be correct for back-lit screens. For the Galaxy Nexus screen, though, Screen Filter does help reducing power draw as a darker screen content = lower brightness.
I used to use SF for quite a while until I got fed up of it causing stutters to most animations. After thorough examination I concluded that the Nexus's GPU is the culprit. For some reason it just doesn't like multiple graphics being updated at once. Modding the overlay XML allows it to run at full speed.
Can anyone confirm the same reduced framerate issue?. It's also the reason why some ROMs include a setting to remove the navigation buttons glow. I tested with CM9 on the SGS2 and experienced none of the stutters in cases where the GN would. Another example: sliding between sections (comments, ralated, etc.) in YouTube is laggy iff the video is playing.
Click to expand...
Click to collapse
Agreed, GPU just isn't good enough. I hate the lag with the button glow animations on!
I use an app called root dim, it's really useful. Let's you use a brightness level of 1, which is really quite dim. Free, too.
Sent from my Galaxy Nexus using XDA App

Remoteconcern said:
Agreed, GPU just isn't good enough. I hate the lag with the button glow animations on!
I use an app called root dim, it's really useful. Let's you use a brightness level of 1, which is really quite dim. Free, too.
Sent from my Galaxy Nexus using XDA App
Click to expand...
Click to collapse
Thanks for the tip, on the Galaxy Nexus it's possible to set the brightness to 0 by writing to /sys/class/backlight/*/brightness but the brightness is checked and reset to the minimum (default 10) every time the screen is turned on. I guess Root Dim works to the same effect so it runs as a system service. Still, it'd be an awesome addition for people who haven't bothered to mod.

fnf said:
That would be correct for back-lit screens. For the Galaxy Nexus screen, though, Screen Filter does help reducing power draw as a darker screen content = lower brightness.
I used to use SF for quite a while until I got fed up of it causing stutters to most animations. After thorough examination I concluded that the Nexus's GPU is the culprit. For some reason it just doesn't like multiple graphics being updated at once. Modding the overlay XML allows it to run at full speed.
Can anyone confirm the same reduced framerate issue?. It's also the reason why some ROMs include a setting to remove the navigation buttons glow. I tested with CM9 on the SGS2 and experienced none of the stutters in cases where the GN would. Another example: sliding between sections (comments, ralated, etc.) in YouTube is laggy iff the video is playing.
Click to expand...
Click to collapse
Screen filter may reduce power. But amoled screens save power with lower brightness. There is no difference between lcd vs led on this issue. And modifying the framework to bring min brightness down to 5 rather than 15 saves much more power than screen filter. Its no contest. This isn't different from lcd in this case.
---------- Post added at 03:20 PM ---------- Previous post was at 03:14 PM ----------
fnf said:
Thanks for the tip, on the Galaxy Nexus it's possible to set the brightness to 0 by writing to /sys/class/backlight/*/brightness but the brightness is checked and reset to the minimum (default 10) every time the screen is turned on. I guess Root Dim works to the same effect so it runs as a system service. Still, it'd be an awesome addition for people who haven't bothered to mod.
Click to expand...
Click to collapse
Yes we can write to that sysfs file, but it gets reset. The mod to the frameworks incorporates that backlight file so its now able to go down to 1, 2, 5, or whatever you want. It makes it now stock, so you are no longer capped at 10 (actually I think 15 is the cap I see). But that mod is just removing this cap and making it lower to whatever you want. Stock.
So no extra app is needed. No additional tweak. It now makes the stock brightness able to go down to 1 by itself whenever it needs.

[Q] AOKP Screen Brightness

The lowest brightness setting is not dim enough for me in low light conditions so I've been looking to alter it.
After reading around the capabilities of some apps it seems that they only add an overlay which reduces contrast. I would much prefer to do it natively.
I then realised that the AOKP ROM has this functionality!
However, I can't seem to get it to work.
Settings>Display>Custom backlight settings
Changing the screen dim level doesn't seem to change anything for me.
Can anyone offer some tips or advice?
Thanks

Works fine for me. I know it doesn't help your problem any...

danger-rat said:
Works fine for me. I know it doesn't help your problem any...
Click to expand...
Click to collapse
Does your display dim more when you select a lower than default value or did you have to change something else?

Did you change the corresponding value in "Edit Other Levels" as well (if you're on auto brightness)? Not on AOKP, but mine is fully functional both on manual, and auto.
Their implementation is the same as CM9 (which is nearly identical, if not the same as the CM7 implementation).
Edit: just a thought, not sure if the AOKP status bar brightness slider is hardcoded to a certain minimum level? Are the results the same if you adjust your brightness via the Settings>Display>Brightness slider?

Settings>Rom Control>Performance>color multipliers.
Drag the three bars all the way down.
As far as your problem...
Are you on auto brightness?
And have you adjusted the "Dim Level" prior to adjusting the screen levels?
(Dim Level is the level your screen dims to after not touching it for 15 seconds or whatever).

Jubakuba said:
And have you adjusted the "Dim Level" prior to adjusting the screen levels?
(Dim Level is the level your screen dims to after not touching it for 15 seconds or whatever).
Click to expand...
Click to collapse
Screen dim level is the minimum brightness value attainable (I lower mine to 12 so I can enter a screen value of 12 in my custom levels), but also does correspond to what you mentioned.

Another AOKP user expressed similar concerns but found an app called Root Dim or something that solved his problem.

OpusX11 said:
Another AOKP user expressed similar concerns but found an app called Root Dim or something that solved his problem.
Click to expand...
Click to collapse
The implementation must be still broken then; haven't tested the latest AOKP releases. Root dim apps tend to create lag.

Implementation works perfectly here.

Jubakuba said:
Implementation works perfectly here.
Click to expand...
Click to collapse
Same.

Jubakuba said:
Implementation works perfectly here.
Click to expand...
Click to collapse
Attaining an altered screen dim level when on auto as well?
Edit: comment wasn't an indictment; just remembering issues that were there on b35 or b36 (?).
Sent from my Galaxy Nexus

Yep.

Microwave. said:
Does your display dim more when you select a lower than default value or did you have to change something else?
Click to expand...
Click to collapse
I select a lower than normal default brightness, and it appears to just work. The auto brightness decreases, which is what i was looking for at night, and also the overall min brightness decreases. The max brightness seems unaffected...

remember when making these changes you do have to save and apply. many people forget that step.

tspderek said:
remember when making these changes you do have to save and apply. many people forget that step.
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Click to collapse
That's an especially annoying mis-step after entering 23 custom levels.

CMNein said:
That's an especially annoying mis-step after entering 23 custom levels.
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Click to collapse
Lol.
And no offense taken at all, man.
And me personally, I just use 5 levels.
One that goes all the way to 600[whateverambientlightismeasuredby] and a screen level of 5.
This keeps my phone from dicking about with it's brightness when I'm indoors...and I have no problem reading it. I don't mind a super-dim screen in general.
The remaining levels I ramp up fairly aggressively for two "by a window" scenarios...
And outside.
And OMGSUNNY outside.

Jubakuba said:
Lol.
And no offense taken at all, man.
And me personally, I just use 5 levels.
One that goes all the way to 600[whateverambientlightismeasuredby] and a screen level of 5.
This keeps my phone from dicking about with it's brightness when I'm indoors...and I have no problem reading it. I don't mind a super-dim screen in general.
The remaining levels I ramp up fairly aggressively for two "by a window" scenarios...
And outside.
And OMGSUNNY outside.
Click to expand...
Click to collapse
I add 2 levels for the high end, and reduce the other brightness levels considerably. Ultimately I usually end up with the perfect'ish level for most scenarios. I hate having to adjust brightness the old fashioned way
Sent from my Galaxy Nexus

CMNein said:
Screen dim level is the minimum brightness value attainable (I lower mine to 12 so I can enter a screen value of 12 in my custom levels), but also does correspond to what you mentioned.
Click to expand...
Click to collapse
Which values do you change in the custom levels?
OpusX11 said:
Another AOKP user expressed similar concerns but found an app called Root Dim or something that solved his problem.
Click to expand...
Click to collapse
Yeah, I know an app could potentially solve the problem but I don't like using 3rd party apps when the solution can be more elegantly achieved using native tweaks.
Jubakuba said:
Lol.
And no offense taken at all, man.
And me personally, I just use 5 levels.
One that goes all the way to 600[whateverambientlightismeasuredby] and a screen level of 5.
This keeps my phone from dicking about with it's brightness when I'm indoors...and I have no problem reading it. I don't mind a super-dim screen in general.
The remaining levels I ramp up fairly aggressively for two "by a window" scenarios...
And outside.
And OMGSUNNY outside.
Click to expand...
Click to collapse
Could you send me a screenshot of your custom levels, that sounds like the exact thing I'm after - a dimmer screen in general, and having a lower min brightness.
So am I correct in thinking that you need to lower the dim value in order to set lower values in the custom levels?

[Q] Decreasing screen brightness under 20 on rooted stock JB 4.1.1

Whatever program I use, I cannot lower the display brightness below 20. I did my best to search the forum as well as the web, but couldn't really find an answer to this. Sorry if I am (possibly) repeating..
I am on stock rooted JB 4.1.1.
My question:
How can I user lower brightness levels? Do I really need a modified kernel for this?
Thanks.

How did u know its 20 % ?
Sent from my SGH-T999 using xda premium

it is not %20. It is 20. Screen brightness level can be set as a value between 0-255.
BTW, I am not talking about stock brightness slider in the status bar. Root applications like RootDim or Tasker allows you to set brightness in terms of actual brightness level. However, values under 20 don't have any effect on decreasing brightness..

[Q] Z1compact: getting minimum brightness LOWER

Hello Everyone,
I have a problem with my amami and I doubt I am the only one but for some reason people do hardly complain: the brightness even at lowest possible setting is still too bright.
I had this back when I had original FW and I am having the same issue with CM11 (latest nightlies). Using manual control or auto-brightness doesn't make much difference, i.e. in a totally dark room the ambient light sensor reports 0Lux and the screen is still too bright.
I found a workaround already (the ScreenFilter app that people recommend all over the internet) but it sucks because it heavily reduces the picture quality, i.e. visibly reduces contrast and especially the gray color resolution. And it also doesn't reduce power consumption like real brightness value change would do.
I looked around for possible solutions and there is a trick with writting a new value of current limit to Linux settings (some mA value between 0 and 20 to some max_current file in procfs). And this really helps but also impacts the maximum brightness, the screen is hardly ready in sun light with reduced current.
Is there a silver bullet? I am thinking about writing an app for that but it would require SU permissions and is kinda dirty to implement. Can anyone recommend a better solution?

have you tried the xposed Modul "minimum brightness" ?

Install Lux Brightness. from play store.
You can overboost it or make the screen so dark that you can't even see it.
Another great screen mod is Twilight which basically dims the screen red based on clock so it helps fall sleep faster when using phone before bed.

New Folder said:
Install Lux Brightness. from play store.
Click to expand...
Click to collapse
Yes, another vote for Lux. It lets you set brightness to negative levels, mine is usually around -50%. https://play.google.com/store/apps/details?id=com.vito.lux&hl=en

Vote for Lux here too.
Nothing comes close

camaro322hp said:
Yes, another vote for Lux. It lets you set brightness to negative levels, mine is usually around -50%. https://play.google.com/store/apps/details?id=com.vito.lux&hl=en
Click to expand...
Click to collapse
Thanks for the hint. I tried the Lite version and AFAICS it simply uses the same trick as ScreenFilter and other "sub-zero" regulators, putting an alpha overlay on top of the image stack.
You can identify this kludge easily by looking at the button areas, they don't get darker anymore. And you can see the black level not getting real black, i.e. the power consumption is not reduced.
However, Lux seems to be one of the better toys because of the plugin interface. Unfortunately there is no HW plugin for Sony devices but judging by the quick look at the Nexus-4 plugin (it's open source!!) it should be possible to adopt this method to Z1 as well. So, maybe when someone could eventually implement that.

xposed Modul "minimum brightness" works, i tested it for you. you can make the screen dim to complete black with your normal display brightness slider without grey or black overlay. it just sets down the minimum brightness level to 1 or 0 (default is 10 or 20), so it should also work with enabled auto brightness

chertVdetali said:
I looked around for possible solutions and there is a trick with writting a new value of current limit to Linux settings (some mA value between 0 and 20 to some max_current file in procfs). And this really helps but also impacts the maximum brightness, the screen is hardly ready in sun light with reduced current.
Click to expand...
Click to collapse
As far as i remember, /proc is only used to call upon information, not to set specific values. What you are looking for is placed within /sys.
To be precise in /sys/devices/leds-qpnp-ee125e00/leds/wled:backlight/. There you will find a file called max_current with which you can easily control the brightness and set it to a very low level. Note that this actually dims the screen and not just applies a filter like most apps do...
One drawback is that the value will change again after you restarted the device. I set up a little flow with Automate β that takes care of this for me. I find this solution a lot better than all the screen filter apps.
This is true for CyanogenMod 11 and GreatDevs Kernel. It might be different on Stock. I know that the path for my Nexus 7 is sys/class/leds/lcd-backlight.
I hope this helps you a little bit.

rob rich said:
xposed Modul "minimum brightness" works, i tested it for you. you can make the screen dim to complete black with your normal display brightness slider without grey or black overlay. it just sets down the minimum brightness level to 1 or 0 (default is 10 or 20), so it should also work with enabled auto brightness
Click to expand...
Click to collapse
I am wondering how you can claim that the result is complete black. Calling this black is like saying "TN monitors have good black values" (I know such people, they change their mind quickly when they see my Eizo with a VA panel at night).
No, seriously, the default was already 10 (see config.xml in cm11 repo) and the difference between 1 and 10 is hardly visible. It's still way too bright for work without eye strain in the darkness.
@Wooaarr: thanks, this is apparently the way to go, I just need to find time to configure it. And yes, of course, the file is in sysfs and not procfs (automated typing, when I grew up with Linux there was no sysfs out there ).

chertVdetali said:
I am wondering how you can claim that the result is complete black. Calling this black is like saying "TN monitors have good black values" (I know such people, they change their mind quickly when they see my Eizo with a VA panel at night).
No, seriously, the default was already 10 (see config.xml in cm11 repo) and the difference between 1 and 10 is hardly visible. It's still way too bright for work without eye strain in the darkness.
@Wooaarr: thanks, this is apparently the way to go, I just need to find time to configure it. And yes, of course, the file is in sysfs and not procfs (automated typing, when I grew up with Linux there was no sysfs out there ).
Click to expand...
Click to collapse
when i disable autobrightness and push the slider to the left my screen goes completely off, so you wanna say that screen off isnt black? funny

chertVdetali said:
Thanks for the hint. I tried the Lite version and AFAICS it simply uses the same trick as ScreenFilter and other "sub-zero" regulators, putting an alpha overlay on top of the image stack.
You can identify this kludge easily by looking at the button areas, they don't get darker anymore. And you can see the black level not getting real black, i.e. the power consumption is not reduced.
However, Lux seems to be one of the better toys because of the plugin interface. Unfortunately there is no HW plugin for Sony devices but judging by the quick look at the Nexus-4 plugin (it's open source!!) it should be possible to adopt this method to Z1 as well. So, maybe when someone could eventually implement that.
Click to expand...
Click to collapse
Interesting information, I did not know that. You are correct, the navigation buttons are brighter than the rest of the screen at negative values. I had noticed that before but didn't know why. Works well enough for me though.

rob rich said:
when i disable autobrightness and push the slider to the left my screen goes completely off, so you wanna say that screen off isnt black? funny
Click to expand...
Click to collapse
Well, you claim that it works for me because you tested it on your device. So... yeah, why not, I could say what you mentioned above just following the same logics. :silly: