TImageEnProc.Contrast3

Declaration

procedure Contrast3(Change, Midpoint: Integer; DoRed, DoGreen, DoBlue: Boolean);

Description

Apply contrast to the image by lightening or darkening pixels depending on whether they are above or below a threshold. The Midpoint value determines the threshold, i.e. the point at which the Change value influences the pixel value lighter or darker.

Parameter	Description
Change	The level of contrast to be applied each side of the midpoint (value between -255 and 255). When positive, increasing the Midpoint value increases the contrast (darkens the image). When negative, Increasing the Midpoint value lightens the image
Midpoint	The threshold of light and dark (value between -100 and 100)
DoRed, DoGreen, DoBlue	If True, changes are applied to that RGB channel

Note: If the image PixelFormat is not ie24RGB, it will be converted

Demo

Demos\ImageEditing\EveryMethod\EveryMethod.dpr

Examples

// Apply Contrast of -24, to the Red and Blue RGB channels only, around a Midpoint of +10, to lighten the overall result:
ImageEnView1.Proc.Intensity( -24, 10, True, False, True );

// Apply Contrast of +15, to the Green RGB channel only, around a Midpoint of +30, to darken the overall result
ImageEnView1.Proc.Intensity( 15, 30, False, True, False );

// Load test image
ImageEnView1.IO.LoadFromFile( 'D:\TestImage.jpg' );

// Apply Contrast of +20 to all RGB values around the default Midpoint value
ImageEnView1.Proc.Contrast3( 20, 0, True, True, True );

TImageEnProc.Contrast3