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.

[Q] How to lower minimum screen brightness?

I know this is possible in CM9's display settings, but I'm currently running AOKP. Is there any other way to lower the minimum screen brightness?
I've given Tasker root permissions, approved it as a device administrator, and approved it as an accessibility service. Still, when I use a task to lower the brightness to very low levels, the brightness will only hold for a fraction of a second before it ramps up to the factory minimum.
So is there some system component I can modify to allow lower brightness, or is this only available as a ROM control like in CM9?

byrong said:
So is there some system component I can modify to allow lower brightness, or is this only available as a ROM control like in CM9?
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FWIW the lowest possible brightness setting can't be altered via the CM9 settings, only the auto brightness levels, both sensor input levels ("bins") and the brightness level associated with that input/bin. The minimum value of 19 for the lowest slot can't be lowered further. There are other display parameters (related to brightness) that can also be altered in the CM9 settings, but it won't accept a value less than 19.
Edit: I see from a link in your sig that you're familiar with the custom levels

Yes we can do it in the frameworks to go lower than 19. I did it on other phones. I'm not sure why it hasnt been done yet for nexus, and ive been too lazy myself.
But we can even take it down to zero or 4-5 etc so its much dimmer at night. Its on my to do list.
Also i posted some kernel code in a similar thread where this question was already asked. But mod the framework is much quicker.

RogerPodacter said:
Yes we can do it in the frameworks to go lower than 19. I did it on other phones. I'm not sure why it hasnt been done yet for nexus, and ive been too lazy myself.
But we can even take it down to zero or 4-5 etc so its much dimmer at night. Its on my to do list.
Also i posted some kernel code in a similar thread where this question was already asked. But mod the framework is much quicker.
Click to expand...
Click to collapse
I should have clarified more clearly that my post above was regarding doing it via the CM settings.
I'll mod mine...at some point...but like you, too lazy for something that won't blow me away.

You want this app, works great https://play.google.com/store/apps/...yZy5wcm9qZWN0dm9vZG9vLmRpc3BsYXlmaWx0ZXIiXQ..
Sent from my Galaxy Nexus GSM using Tapatalk expect possible typos

I'm an idiot; I just found it in AOKP. It's in the custom backlight settings.
My experience does not mirror you guys. When I decrease the "screen dim level" in the custom brightness settings, it applies globally. I just did it in AOKP the same way I used to in CM9 and now with Tasker I've taken the screen all the way down to 1

Is there any way to decrease the minimum brightness on stock?

aidanbree said:
Is there any way to decrease the minimum brightness on stock?
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Yes with above linked app. I confirm it works on stock
Sent from my Galaxy Nexus using Tapatalk

I've used a similar app called Screen Filter. My only problem with these types of apps is that I find the black/gray filter they use greatly decreases contrast at low brightness levels (more so than a "true" brightness level at an equivalent setting). Still, if you are running a setup in which they are your only option, they certainly beat having nothing.

The problem with using a screen filter is that it limits the maximum brightness when in sunlight.
I only want to affect the minimum as it is too bright.

Has anyone been able to do this on a stock rom? I too think that the minimum brightness is too high, but I don't want to use the above linked program because it also affects the maximum brightness too. I would like to be able to set custom light levels as per cm9/cm10 and pretty much any custom ROM right now, albeit with my stock ROM. Any flashable zips out there?
Cheers,
Dan

Screen Brightness adjustment

Hi guys, i was just wondering,
i want to adjust the brightness level in my Gnex according to my taste, which is set the minimum at 25% and then up to 100%. Ultra low brightness as found in stock and custom roms makes the screen look horrible, at 25% its 1000x better.
Now the tricky part is that i want to leave it at auto, simplyfying it i would like to have the brightness set at auto but the min and max values at 25-100%
How can i do this?
thanx in advance

Tweaked brightness settings - battery saving and readable (edit through CM settings)

I've come up with some great (I think so..) brightness settings for the Razr M. I worked on this to make sure of battery savings while remaining comfortably readable under any light conditions. So here they are if you are interested in having a go:
0 lux - 4% screen brightness
2 lux - 4%
3 lux - 6%
7 lux - 8%
22 lux - 10%
63 lux - 14%
180 lux - 22%
511 lux - 31%
1447 lux - 43%
4095 lux - 57%
11585 lux - 74%
32768 to infinity - 95%
You have to edit them in manually through CM settings, attached is the smooth graph of the outcome (from CM itself):
One thing that has annoyed me on any phone I've had is the auto brightness settings, so I did a bit a research into how the human eye perceives light increase, and its based roughly on log(lux), increasing screen brightness by ^2.5 each step. Result is that I wrote an excel sheet (also attached) with some cool maths where you can adjust some variables to tailor an auto-brightness curve to your taste.
I made a few assumptions specific to the Razr M for the above settings:
- It has a minimum light reading of 2 lux even in the darkest of darks (my defy did the same thing - might be a motorola thing)
- The lux reading is approximately accurate (my galaxy note 8 and Razr M give VERY similar readings under the same light sources)
- I topped the lux reading out at 32k (it does read up to 65k) because its around the starting value of direct sunlight, and it also happens to be a nice round number
Just thought I'd share because I think I nailed the auto brightness settings on this device.
Cheers

How did you get that many step points? I only see 0, 15, 100, 3000 and 8000-infinity.
I am running CM11.2 (4.4.3).
---------- Post added at 10:26 AM ---------- Previous post was at 10:14 AM ----------
Nevermind. Found it by long pressing a segment and choosing "split". Not real intuitive but it works.

Yeah you have to add in a few extra points with my setup. You could probably skip say every second point and it would work almost as well. But the built in brightness points ramped up to quickly for my liking - far brighter then necessary.

Where exactly do you go to in CM to modify these settings? I can't find them...

Display&Lights -- Brightness -- click on the settings icon next to the slider

I didn't mention in the first post, but the excel sheet is very customisable...
If you want to lower brightness there are several ways:
1. lower the maximum brightness
2. Increase the curve value (this affects the middle range of the curve mostly)
3. Increase the maximum lux value
Or if you want to increase brightness, just do the opposite of the points above. You know you have good settings when it looks the same always (ie doesn't suddently appear dim or bright). I think my default value are pretty close. I spent some time fine tuning, but like anything, there is always room for improvement
I also did this calculator so I didn't have to run another app in the background to control auto brightness.. save on a few MB of ram anyway.

Rufus said:
I didn't mention in the first post, but the excel sheet is very customisable...
If you want to lower brightness there are several ways:
1. lower the maximum brightness
2. Increase the curve value (this affects the middle range of the curve mostly)
3. Increase the maximum lux value
Or if you want to increase brightness, just do the opposite of the points above. You know you have good settings when it looks the same always (ie doesn't suddently appear dim or bright). I think my default value are pretty close. I spent some time fine tuning, but like anything, there is always room for improvement
I also did this calculator so I didn't have to run another app in the background to control auto brightness.. save on a few MB of ram anyway.
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Click to collapse
hello can u tell me more about the curve value? which range can be set? and whats the behave on mobile?

[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.
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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
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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
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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 ).
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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.
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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
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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: