Question: Is there an app that can adjust gamma/brightness/contrast for ubuntu 16.04?

`xgamma` doesn't have any effect.

Thank you

**Edits**

```
 *-display:0             
       description: VGA compatible controller
       product: Mobile 4 Series Chipset Integrated Graphics Controller
       vendor: Intel Corporation
       physical id: 2
       bus info: pci@0000:00:02.0
       version: 09
       width: 64 bits
       clock: 33MHz
       capabilities: msi pm vga_controller bus_master cap_list rom
       configuration: driver=i915 latency=0
       resources: irq:27 memory:d0000000-d03fffff memory:c0000000-cfffffff ioport:50f0(size=8)
  *-display:1 UNCLAIMED
       description: Display controller
       product: Mobile 4 Series Chipset Integrated Graphics Controller
       vendor: Intel Corporation
       physical id: 2.1
       bus info: pci@0000:00:02.1
       version: 09
       width: 64 bits
       clock: 33MHz
       capabilities: pm bus_master cap_list
       configuration: latency=0
       resources: memory:d3400000-d34fffff

```

Answer: 
**Note this is not a app but a script can be made if the process works on your pc**

Open your terminal and enter this command.

`xrandr -q | grep " connected"`

My output is: 
**DVI-I-0 connected primary 1280x1024+0+0 (normal left inverted right x axis y axis) 376mm x 301mm**

Copy the value that comes before "connected".
In my case as you can see its "DVI-I-0" Yours might me something else.

Now try this command replacing "DVI-I-0" with the value you got from the previous command.

`xrandr --output DVI-I-0 --gamma 0.5:0.5:0.5`

`xrandr --output your_value --gamma 0.5:0.5:0.5`

The last three decimal values separated by colon sets the gamma value.
The values have a range from 1.0:1.0:1.0 to 0.0:0.0:0.0
Default is 1.0:1.0:1.0

**Note:: I use xrandr to set brightness on my display. It will sometimes reset to the default value, sometimes during a program launch. So I use a script with a desktop shortcut for convenience.**
As shown in other answer:

```
xrandr --output your_display_name --gamma 0.5:0.5:0.5

```

To automatically apply *xrandr* options on each login, commands can be done in a simple Python script **added to "Startup Applications"** in Ubuntu.

~/xrandr\_display\_setup.py:

```py
#!/usr/bin/env python3

import subprocess as sp

# R:G:B, float nums 0 to 1
gamma = '0.85:0.85:0.85'

def output(cmd):
    return sp.check_output(cmd, shell=True).decode('utf-8').strip()

def set_gamma(display):
    sp.run('xrandr --output {0} --gamma {1}'.format(display, gamma).split())

# `line` e.g.  "HDMI-2 connected primary 1920x1080+0+0 (normal..."
line = output('xrandr -q | grep " connected"')
if line:
    display = line.split()[0]
    set_gamma(display)

exit(0)

```