GammaCorrect method (Main Control)

Visual Basic example
Visual C++ 4.0 example

Access 2.0 example

Access 95, 97 example
Visual J++ example

Syntax short GammaCorrect (short iGamma);

Overview:  Refer to Changing Brightness and Contrast.

Remarks

Adjusts the intensity of colors in the bitmap by changing the gamma constant that is used to map the intensity values.

Intensity values ideally follow a logarithmic progression, because the eye perceives changes in intensity as being equal when the ratio of change is equal. For example, we would see a change from 0.1 to 0.2 as being equal to a change from 0.2 to 0.4.

Gamma is a standard constant that is used to calculate the progression. For most CRTs the gamma constant is in the range of 2.2 to 2.5.

This method supports 12 and 16-bit grayscale and 48 and 64-bit color images. Support for 12 and 16-bit grayscale images and 48 and 64-bit color images is available only in the Document/Medical toolkits.

See Also

Elements:  Intensity method, Contrast method, HistoContrast method, HistoEqualize method, StretchIntensity method

Topics:  Raster Images: Modifying Intensity Values
Raster Images: Where the Region Preempts the Bitmap