[PLUG] Ambient light screen adjustment

Sat May 2 01:31:38 UTC 2020

The HP Compaq Pro 6300 has a camera in the top of the bezel.
That was my idea that it would use the camera to get the light
info. Seems it should be pretty straight forward you look at the
pixels get an average of them all and adjust the screen based on
preset levels. I am not sure why it would need another sensor
using cameras to look at light levels has been done for a long
time. A single sensor (pixel) or multiple sensors (camera sensor)
are still light detectors. Here is a link to the machine description.
https://support.hp.com/us-en/document/c03443420
Here is what is says about the camera:
Integrated 2.0 MP webcam (up to 30 frames/sec)
1600x1200 resolution. So all I need to find is something
that can take that info and convert it into monitor intensity
control.

On Fri, May 1, 2020 at 10:44 AM Tomas Kuchta <tomas.kuchta.lists at gmail.com>
wrote:

> If this is a laptop, you could always take a picture with it's camera using
> mplayer, then get average brightness using imagemagick or similar instead
> of trying to get the light sensor working.
>
> On Fri, May 1, 2020, 08:39 Tomas Kuchta <tomas.kuchta.lists at gmail.com>
> wrote:
>
> > If you can find the light sensor in devices, probably/hopefully USB. It
> > could even be exposed in Dbus. You could cludge some daemon together
> > checking it every 10sec or so and adjusting the brightness by sending
> > messages to the screen via Dbus.
> >
> > It is the same idea as pressing the brightness keys on your keyboard.
> >
> > That is if you can find a way to get value off your light sensor. Other
> > than that, you would need external light sensor to get the light info.
> >
> > This is not much of a help ....
> > Tomas
> >
> > On Fri, May 1, 2020, 07:21 Chuck Hast <wchast at gmail.com> wrote:
> >
> >> That is kind of a pita because this screen is in a location where
> >> during the early morning and evening, lights are turned on and
> >> off. When off we want the screen to drop way down but when
> >> on it needs to come back up so it will be visible again. I know
> >> it works, I have a laptop that has Mate on it and it does it automagicly
> >> I did not even install it. But on this machine I do not even see
> >> see the setup for auto adjust.
> >> I am going to move it to 20.04 anyhow, and the ambient light
> >> auto adjust is quite clearly in 20.04.  Maybe with the install the
> >> system did not see the hardware to do this auto ambient and
> >> just did not install it, not sure. But I know that the HP Compaq
> >> 6300 does have the hardware for it as I see windows setup info
> >> for dealing with it.
> >>
> >>
> >> On Fri, May 1, 2020 at 12:21 AM wes <plug at the-wes.com> wrote:
> >>
> >> > obligatory suggestion that is not what you asked for and you have
> >> probably
> >> > already considered:
> >> >
> >> > it would probably be a lot easier to adjust the brightness on a
> schedule
> >> > rather than based on ambient light.
> >> >
> >> > -wes
> >> >
> >> > On Thu, Apr 30, 2020 at 7:24 PM Chuck Hast <wchast at gmail.com> wrote:
> >> >
> >> > > Folks,
> >> > > I have a HP Compaq 6300 I am using as a DVR terminal to my DVR which
> >> is
> >> > > elsewhere on the property. The 6300 just displays the critical
> camera
> >> > > screens.
> >> > >
> >> > > My issue is that I am trying to figure out how to use the camera on
> >> the
> >> > > machine
> >> > > to detect ambient light and adjust screen brightness. I see a lot
> >> about
> >> > Win
> >> > > 10
> >> > > doing so bidden or not. But do not see much about this in Linux. The
> >> > issue
> >> > > is
> >> > > the screen is so bright at night that it bothers my wife. But we do
> >> not
> >> > > want to
> >> > > turn it off because if we hear something outside the first thing we
> >> do is
> >> > > look at
> >> > > the screen to see what the cameras are seeing. Since the machine is
> >> > mounted
> >> > > on the wall for viewing there is no keyboard on it and even if there
> >> was
> >> > > wife
> >> > > probably would not try to adjust it.
> >> > >
> >> > > Any ideas on how to use the on board camera to adjust screen
> >> brightness?
> >> > > --
> >> > >
> >> > > Chuck Hast  -- KP4DJT --
> >> > > I can do all things through Christ which strengtheneth me.
> >> > > Ph 4:13 KJV
> >> > > Todo lo puedo en Cristo que me fortalece.
> >> > > Fil 4:13 RVR1960
> >> > > _______________________________________________
> >> > > PLUG mailing list
> >> > > PLUG at pdxlinux.org
> >> > > http://lists.pdxlinux.org/mailman/listinfo/plug
> >> > >
> >> > _______________________________________________
> >> > PLUG mailing list
> >> > PLUG at pdxlinux.org
> >> > http://lists.pdxlinux.org/mailman/listinfo/plug
> >> >
> >>
> >>
> >> --
> >>
> >> Chuck Hast  -- KP4DJT --
> >> I can do all things through Christ which strengtheneth me.
> >> Ph 4:13 KJV
> >> Todo lo puedo en Cristo que me fortalece.
> >> Fil 4:13 RVR1960
> >> _______________________________________________
> >> PLUG mailing list
> >> PLUG at pdxlinux.org
> >> http://lists.pdxlinux.org/mailman/listinfo/plug
> >>
> >
> _______________________________________________
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>

-- 

Chuck Hast  -- KP4DJT --
I can do all things through Christ which strengtheneth me.
Ph 4:13 KJV
Todo lo puedo en Cristo que me fortalece.
Fil 4:13 RVR1960