Gammit! An easy to use application for desktop gamma correction

• Download the compiled tool only - 37.8 Kb
• Download source - 100 Kb

Introduction

I own an LCD monitor, and the default CRT gamma level makes it too bright for me. For various reasons, some application or situation can set the gamma level of my monitor to this value, ignoring my settings, and each time I must open Catalyst (which needs time to start, and consumes a huge quantity of memory) to readjust the settings. So I decided to find something to save my gamma correction level and which would let me restore the saved value with only a click (on the taskbar area would be perfect). Searching on CodeProject for some solution took me to this article: Gamma correction slider by Dany Cantin. Yes, it did the work but not as I wanted. First, I tried to edit the code, but then I found that a from-0 solution would be easier. So I did it.

The Code

I made the application in .NET 2.0, using C#. It was very easy and fast, and the program did its dirty work well. As you can see, in the code, I re-used the Dany routine to calculate the SetGammaRamp argument, starting from the gamma level. I know it isn't a long or hard code, but I've used it because it works and so it would be stupid to rewrite it and waste time.

For seting the value..

for (int i = 0; i < 256; i++)
{
    ramp[i] = ramp[i + 256] = ramp[i + 512] =
    (UInt16)Math.Min(65535, Math.Max(0, 
            Math.Pow((float)((i + 1) / 256.0), 
            (float)Gamma) * 65535 + 0.5));
}

and to get it:

float[] rgb = { 1.0f, 1.0f, 1.0f };

for (int i = 0; i < 3; i++)
{
    float Csum = 0.0f;
    int Ccount = 0;
    int min = 256 * i;
    int max = min + 256;

    for (int j = min; j < max; j++)
    {
        if (j != 0 && _RampSaved[j] != 0)
        {
            double B = (j % 256) / 256.0;
            double A = _RampSaved[j] / 65536.0;
            float C = (float)(Math.Log(A) / Math.Log(B));

            Csum += C;
            Ccount++;
        }
    }

    rgb[i] = Csum / Ccount;
}
return rgb[0];

Conclusions

So, that's all, I think. I hope you'll find it useful, bye!