Software adjustment of LCD monitor brightness in Raspberry Pi












4














This is my first post here. I'm at the beginning of the road called Raspberry Pi.



Is there any way of changing the gamma/contrast/brightness of monitor via Raspberry Pi?



My Samsung 960BF doesn't have any hardware adjustment, only a power button.



I tried using xbacklight and got error




"No outputs have backlight property".




gddccontrol also didn't work. Error:



I/O warning: failed to load external entity "/home/pi/.dccontrol/monitorlist"  
Document not parsed successfully
Probing for available monitors"


And nothing is happening.



I connected my monitor through DVI-HDMI cable. Maybe this is why it doesn't work?



I'm using Raspberry Pi B+ V1.2 with Raspbian.










share|improve this question





























    4














    This is my first post here. I'm at the beginning of the road called Raspberry Pi.



    Is there any way of changing the gamma/contrast/brightness of monitor via Raspberry Pi?



    My Samsung 960BF doesn't have any hardware adjustment, only a power button.



    I tried using xbacklight and got error




    "No outputs have backlight property".




    gddccontrol also didn't work. Error:



    I/O warning: failed to load external entity "/home/pi/.dccontrol/monitorlist"  
    Document not parsed successfully
    Probing for available monitors"


    And nothing is happening.



    I connected my monitor through DVI-HDMI cable. Maybe this is why it doesn't work?



    I'm using Raspberry Pi B+ V1.2 with Raspbian.










    share|improve this question



























      4












      4








      4


      1





      This is my first post here. I'm at the beginning of the road called Raspberry Pi.



      Is there any way of changing the gamma/contrast/brightness of monitor via Raspberry Pi?



      My Samsung 960BF doesn't have any hardware adjustment, only a power button.



      I tried using xbacklight and got error




      "No outputs have backlight property".




      gddccontrol also didn't work. Error:



      I/O warning: failed to load external entity "/home/pi/.dccontrol/monitorlist"  
      Document not parsed successfully
      Probing for available monitors"


      And nothing is happening.



      I connected my monitor through DVI-HDMI cable. Maybe this is why it doesn't work?



      I'm using Raspberry Pi B+ V1.2 with Raspbian.










      share|improve this question















      This is my first post here. I'm at the beginning of the road called Raspberry Pi.



      Is there any way of changing the gamma/contrast/brightness of monitor via Raspberry Pi?



      My Samsung 960BF doesn't have any hardware adjustment, only a power button.



      I tried using xbacklight and got error




      "No outputs have backlight property".




      gddccontrol also didn't work. Error:



      I/O warning: failed to load external entity "/home/pi/.dccontrol/monitorlist"  
      Document not parsed successfully
      Probing for available monitors"


      And nothing is happening.



      I connected my monitor through DVI-HDMI cable. Maybe this is why it doesn't work?



      I'm using Raspberry Pi B+ V1.2 with Raspbian.







      debian display raspberry-pi raspbian






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited Jul 9 '15 at 20:15

























      asked Jul 8 '15 at 11:28









      tarzanno

      77415




      77415






















          1 Answer
          1






          active

          oldest

          votes


















          0














          One tool I have used successfully (not on a pi though), is xcalib from the package of the same name. You can use it to change the gamma, eg:



          xcalib -gc 1.1 -a


          You can repeat this. To cancel use



          xcalib -clear


          Another useful option is making the whole screen reverse-video:



           xcalib -invert -a


          It is intended to work with icc profiles, but I have only used the above commands.






          share|improve this answer





















          • Thanks for reply. I tried this, but nothing happens, end after executing command: xcalib -b 99 there is an error: "Warning: Unable to read file ' ' "
            – tarzanno
            Jul 8 '15 at 13:44












          • You would need -b 99 -a but I wouldnt do that, the screen will be all white.
            – meuh
            Jul 11 '15 at 4:34










          • Unfortunately, it doesn't work either. I tried 'xcalib -b 99 -a', 'sudo xcalib -b 99 -a' , and 'xcalib -b 10 -a' to make sure my monitor is not set to max brightness already. There is no error and nothing is happening. I'm afraid that I will need to learn i2c and control the monitor by that...
            – tarzanno
            Jul 11 '15 at 11:47










          • Perhaps your cable is not passing through the i2c data line. Look in your /var/log/Xorg.0.log or similar log file to see if the display's eeprom was found (look for EDID).
            – meuh
            Jul 11 '15 at 12:12












          • Nothing like that exists in this file. There is only a line telling that Rpi is using default monitor and : "no device specified for default monitor section". Must I buy a new HDMI-DVI cable, or there is another way?
            – tarzanno
            Jul 11 '15 at 12:31











          Your Answer








          StackExchange.ready(function() {
          var channelOptions = {
          tags: "".split(" "),
          id: "3"
          };
          initTagRenderer("".split(" "), "".split(" "), channelOptions);

          StackExchange.using("externalEditor", function() {
          // Have to fire editor after snippets, if snippets enabled
          if (StackExchange.settings.snippets.snippetsEnabled) {
          StackExchange.using("snippets", function() {
          createEditor();
          });
          }
          else {
          createEditor();
          }
          });

          function createEditor() {
          StackExchange.prepareEditor({
          heartbeatType: 'answer',
          autoActivateHeartbeat: false,
          convertImagesToLinks: true,
          noModals: true,
          showLowRepImageUploadWarning: true,
          reputationToPostImages: 10,
          bindNavPrevention: true,
          postfix: "",
          imageUploader: {
          brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
          contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
          allowUrls: true
          },
          onDemand: true,
          discardSelector: ".discard-answer"
          ,immediatelyShowMarkdownHelp:true
          });


          }
          });














          draft saved

          draft discarded


















          StackExchange.ready(
          function () {
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fsuperuser.com%2fquestions%2f937829%2fsoftware-adjustment-of-lcd-monitor-brightness-in-raspberry-pi%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown

























          1 Answer
          1






          active

          oldest

          votes








          1 Answer
          1






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes









          0














          One tool I have used successfully (not on a pi though), is xcalib from the package of the same name. You can use it to change the gamma, eg:



          xcalib -gc 1.1 -a


          You can repeat this. To cancel use



          xcalib -clear


          Another useful option is making the whole screen reverse-video:



           xcalib -invert -a


          It is intended to work with icc profiles, but I have only used the above commands.






          share|improve this answer





















          • Thanks for reply. I tried this, but nothing happens, end after executing command: xcalib -b 99 there is an error: "Warning: Unable to read file ' ' "
            – tarzanno
            Jul 8 '15 at 13:44












          • You would need -b 99 -a but I wouldnt do that, the screen will be all white.
            – meuh
            Jul 11 '15 at 4:34










          • Unfortunately, it doesn't work either. I tried 'xcalib -b 99 -a', 'sudo xcalib -b 99 -a' , and 'xcalib -b 10 -a' to make sure my monitor is not set to max brightness already. There is no error and nothing is happening. I'm afraid that I will need to learn i2c and control the monitor by that...
            – tarzanno
            Jul 11 '15 at 11:47










          • Perhaps your cable is not passing through the i2c data line. Look in your /var/log/Xorg.0.log or similar log file to see if the display's eeprom was found (look for EDID).
            – meuh
            Jul 11 '15 at 12:12












          • Nothing like that exists in this file. There is only a line telling that Rpi is using default monitor and : "no device specified for default monitor section". Must I buy a new HDMI-DVI cable, or there is another way?
            – tarzanno
            Jul 11 '15 at 12:31
















          0














          One tool I have used successfully (not on a pi though), is xcalib from the package of the same name. You can use it to change the gamma, eg:



          xcalib -gc 1.1 -a


          You can repeat this. To cancel use



          xcalib -clear


          Another useful option is making the whole screen reverse-video:



           xcalib -invert -a


          It is intended to work with icc profiles, but I have only used the above commands.






          share|improve this answer





















          • Thanks for reply. I tried this, but nothing happens, end after executing command: xcalib -b 99 there is an error: "Warning: Unable to read file ' ' "
            – tarzanno
            Jul 8 '15 at 13:44












          • You would need -b 99 -a but I wouldnt do that, the screen will be all white.
            – meuh
            Jul 11 '15 at 4:34










          • Unfortunately, it doesn't work either. I tried 'xcalib -b 99 -a', 'sudo xcalib -b 99 -a' , and 'xcalib -b 10 -a' to make sure my monitor is not set to max brightness already. There is no error and nothing is happening. I'm afraid that I will need to learn i2c and control the monitor by that...
            – tarzanno
            Jul 11 '15 at 11:47










          • Perhaps your cable is not passing through the i2c data line. Look in your /var/log/Xorg.0.log or similar log file to see if the display's eeprom was found (look for EDID).
            – meuh
            Jul 11 '15 at 12:12












          • Nothing like that exists in this file. There is only a line telling that Rpi is using default monitor and : "no device specified for default monitor section". Must I buy a new HDMI-DVI cable, or there is another way?
            – tarzanno
            Jul 11 '15 at 12:31














          0












          0








          0






          One tool I have used successfully (not on a pi though), is xcalib from the package of the same name. You can use it to change the gamma, eg:



          xcalib -gc 1.1 -a


          You can repeat this. To cancel use



          xcalib -clear


          Another useful option is making the whole screen reverse-video:



           xcalib -invert -a


          It is intended to work with icc profiles, but I have only used the above commands.






          share|improve this answer












          One tool I have used successfully (not on a pi though), is xcalib from the package of the same name. You can use it to change the gamma, eg:



          xcalib -gc 1.1 -a


          You can repeat this. To cancel use



          xcalib -clear


          Another useful option is making the whole screen reverse-video:



           xcalib -invert -a


          It is intended to work with icc profiles, but I have only used the above commands.







          share|improve this answer












          share|improve this answer



          share|improve this answer










          answered Jul 8 '15 at 13:28









          meuh

          3,4101921




          3,4101921












          • Thanks for reply. I tried this, but nothing happens, end after executing command: xcalib -b 99 there is an error: "Warning: Unable to read file ' ' "
            – tarzanno
            Jul 8 '15 at 13:44












          • You would need -b 99 -a but I wouldnt do that, the screen will be all white.
            – meuh
            Jul 11 '15 at 4:34










          • Unfortunately, it doesn't work either. I tried 'xcalib -b 99 -a', 'sudo xcalib -b 99 -a' , and 'xcalib -b 10 -a' to make sure my monitor is not set to max brightness already. There is no error and nothing is happening. I'm afraid that I will need to learn i2c and control the monitor by that...
            – tarzanno
            Jul 11 '15 at 11:47










          • Perhaps your cable is not passing through the i2c data line. Look in your /var/log/Xorg.0.log or similar log file to see if the display's eeprom was found (look for EDID).
            – meuh
            Jul 11 '15 at 12:12












          • Nothing like that exists in this file. There is only a line telling that Rpi is using default monitor and : "no device specified for default monitor section". Must I buy a new HDMI-DVI cable, or there is another way?
            – tarzanno
            Jul 11 '15 at 12:31


















          • Thanks for reply. I tried this, but nothing happens, end after executing command: xcalib -b 99 there is an error: "Warning: Unable to read file ' ' "
            – tarzanno
            Jul 8 '15 at 13:44












          • You would need -b 99 -a but I wouldnt do that, the screen will be all white.
            – meuh
            Jul 11 '15 at 4:34










          • Unfortunately, it doesn't work either. I tried 'xcalib -b 99 -a', 'sudo xcalib -b 99 -a' , and 'xcalib -b 10 -a' to make sure my monitor is not set to max brightness already. There is no error and nothing is happening. I'm afraid that I will need to learn i2c and control the monitor by that...
            – tarzanno
            Jul 11 '15 at 11:47










          • Perhaps your cable is not passing through the i2c data line. Look in your /var/log/Xorg.0.log or similar log file to see if the display's eeprom was found (look for EDID).
            – meuh
            Jul 11 '15 at 12:12












          • Nothing like that exists in this file. There is only a line telling that Rpi is using default monitor and : "no device specified for default monitor section". Must I buy a new HDMI-DVI cable, or there is another way?
            – tarzanno
            Jul 11 '15 at 12:31
















          Thanks for reply. I tried this, but nothing happens, end after executing command: xcalib -b 99 there is an error: "Warning: Unable to read file ' ' "
          – tarzanno
          Jul 8 '15 at 13:44






          Thanks for reply. I tried this, but nothing happens, end after executing command: xcalib -b 99 there is an error: "Warning: Unable to read file ' ' "
          – tarzanno
          Jul 8 '15 at 13:44














          You would need -b 99 -a but I wouldnt do that, the screen will be all white.
          – meuh
          Jul 11 '15 at 4:34




          You would need -b 99 -a but I wouldnt do that, the screen will be all white.
          – meuh
          Jul 11 '15 at 4:34












          Unfortunately, it doesn't work either. I tried 'xcalib -b 99 -a', 'sudo xcalib -b 99 -a' , and 'xcalib -b 10 -a' to make sure my monitor is not set to max brightness already. There is no error and nothing is happening. I'm afraid that I will need to learn i2c and control the monitor by that...
          – tarzanno
          Jul 11 '15 at 11:47




          Unfortunately, it doesn't work either. I tried 'xcalib -b 99 -a', 'sudo xcalib -b 99 -a' , and 'xcalib -b 10 -a' to make sure my monitor is not set to max brightness already. There is no error and nothing is happening. I'm afraid that I will need to learn i2c and control the monitor by that...
          – tarzanno
          Jul 11 '15 at 11:47












          Perhaps your cable is not passing through the i2c data line. Look in your /var/log/Xorg.0.log or similar log file to see if the display's eeprom was found (look for EDID).
          – meuh
          Jul 11 '15 at 12:12






          Perhaps your cable is not passing through the i2c data line. Look in your /var/log/Xorg.0.log or similar log file to see if the display's eeprom was found (look for EDID).
          – meuh
          Jul 11 '15 at 12:12














          Nothing like that exists in this file. There is only a line telling that Rpi is using default monitor and : "no device specified for default monitor section". Must I buy a new HDMI-DVI cable, or there is another way?
          – tarzanno
          Jul 11 '15 at 12:31




          Nothing like that exists in this file. There is only a line telling that Rpi is using default monitor and : "no device specified for default monitor section". Must I buy a new HDMI-DVI cable, or there is another way?
          – tarzanno
          Jul 11 '15 at 12:31


















          draft saved

          draft discarded




















































          Thanks for contributing an answer to Super User!


          • Please be sure to answer the question. Provide details and share your research!

          But avoid



          • Asking for help, clarification, or responding to other answers.

          • Making statements based on opinion; back them up with references or personal experience.


          To learn more, see our tips on writing great answers.





          Some of your past answers have not been well-received, and you're in danger of being blocked from answering.


          Please pay close attention to the following guidance:


          • Please be sure to answer the question. Provide details and share your research!

          But avoid



          • Asking for help, clarification, or responding to other answers.

          • Making statements based on opinion; back them up with references or personal experience.


          To learn more, see our tips on writing great answers.




          draft saved


          draft discarded














          StackExchange.ready(
          function () {
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fsuperuser.com%2fquestions%2f937829%2fsoftware-adjustment-of-lcd-monitor-brightness-in-raspberry-pi%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown





















































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown

































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown







          Popular posts from this blog

          If I really need a card on my start hand, how many mulligans make sense? [duplicate]

          Alcedinidae

          Can an atomic nucleus contain both particles and antiparticles? [duplicate]