Click here to Skip to main content
Click here to Skip to main content

Gamma correction slider

, 3 Nov 2002 CPOL
Rate this:
Please Sign up or sign in to vote.
Slider control class to perform gamma correction.

Sample Image - Gamma_Manager.gif


Gamma Manager is based on Gamma Slider control. This control allows to change gamma monitor on most graphic cards. The goal for this project is very simple and control is for VC6 & VC7.

The other day I downloaded a N64 emulator but the screen was so black that I did not see anything. I had thus to find this solution to lighten my screen. I know that the tools of my video chart make it possible to change gamma of my screen, but it is faster with this tool.


The implementation of this slider control is very easy.

  1. Import GammaSlider.h and GammaSlider.cpp into your project.
  2. Include reference to the class control.
  3. Add slider control on a form.
  4. Use ClassWizard to declare variable name derived from CGammaSlider control.
  5. That's it, enjoy!

Under the hood

Windows provides two APIs GetDeviceGammaRamp/ SetDeviceGammaRamp to perform gamma correction. In fact we need to have a 3 dimensional buffer of 256 WORD to manipulate gamma correction. To change gamma, it is necessary to change the RGB value of each color contained in the buffer by a float factor between 0.0 and 2.0.


  • We need to save current gamma for future restore.
    WORD m_RampSaved[256*3]; 
    if (!GetDeviceGammaRamp(::GetDC(NULL), m_RampSaved))
        TRACE("WARNING: Cannot initialize DeviceGammaRamp.\n");
  • To change gamma, cycle into ramp buffer and change RGB color where Gamma is the float factor.
    WORD ramp[256*3];
    for( int i=0; i<256; i++ ) {
        ramp[i+0] = ramp[i+256] = ramp[i+512] = 
        (WORD)min(65535, max(0, pow((i+1) / 256.0, Gamma) * 65535 + 0.5));
    SetDeviceGammaRamp(::GetDC(NULL), ramp);
  • Now to trap slider control message, we need to use a special message ON_WM_HSCROLL_REFLECT() that can provide message to be dispatched into control class itself.


  • v1.1 - Added functions LoadSettings and SaveSettings
  • v1.0 - Initial release


This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


About the Author

Canada Canada

Comments and Discussions

GeneralC#.Net version for setting brightnessness/contrast for your screen PinmemberGamePlanner9-May-09 14:28 
Question!!Important!!I found a problem for Gamma correction slider!! Pinmemberstrongpan19-Jan-09 19:57 
General.Net version Pinmembernasserdw3-Oct-07 0:49 
GeneralRe: .Net version Pinmemberfos3_cpp8-Jan-09 5:32 
GeneralSetDeviceGammaRamp Operation Pinmembernikki69010310-Dec-06 21:47 
QuestionSetDeviceGammaRamp Operation Pinmembernikki69010310-Dec-06 20:53 
QuestionPOW Pinmemberbeckers95610-Sep-06 5:19 
AnswerRe: POW Pinmemberslawekkowalski25-Aug-07 5:22 
GeneralDual Monitors Pinmembersrboisvert27-Jul-06 3:54 
GeneralScreen Darkness Pinmembergeorgeantohe8-Jun-06 10:38 
GeneralRGB correction PinmemberRobsori3-May-06 21:43 
GeneralCorrection for Geforce Card PinmemberDigitalCAS28-Dec-03 8:04 
GeneralRe: Correction for Geforce Card PinmemberSynetech5-May-06 21:01 
QuestionIs this code free? Can it be used for any purposes? Pinmemberradiaki25-May-03 13:03 
AnswerRe: Is this code free? Can it be used for any purposes? PinmemberDany Cantin25-May-03 15:36 
Generalneed help for similar control in EVC++ for windows CE 3.0 Pinmemberdeepmala24-Mar-03 22:58 
GeneralHoping for help. Pinmemberjinxie31-Jan-03 1:21 
GeneralRe: Hoping for help. PinmemberChristian Graus31-Jan-03 2:08 
GeneralAlso... PinmemberNorm Almond4-Nov-02 22:14 
GeneralBug! PinmemberNorm Almond4-Nov-02 22:03 
GeneralRe: Bug! PinmemberDany Cantin5-Nov-02 7:21 
GeneralRe: Bug! Pinmembersirb22-Dec-08 3:56 
GeneralSaving Settings PinmemberNorm Almond3-Nov-02 0:13 
GeneralRe: Saving Settings PinmemberDany Cantin3-Nov-02 17:10 
GeneralWow, what a GREAT guy! PinmemberDeviantCoding1-Nov-02 16:34 

General General    News News    Suggestion Suggestion    Question Question    Bug Bug    Answer Answer    Joke Joke    Rant Rant    Admin Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.

| Advertise | Privacy | Terms of Use | Mobile
Web01 | 2.8.150302.1 | Last Updated 4 Nov 2002
Article Copyright 2002 by DCUtility
Everything else Copyright © CodeProject, 1999-2015
Layout: fixed | fluid