ImageAttributes Class

An ImageAttributes object maintains several color-adjustment settings, including color-adjustment matrices, grayscale-adjustment matrices, gamma-correction values, color-map tables, and color-threshold values. During rendering, colors can be corrected, darkened, lightened, and removed. To apply such manipulations, initialize an ImageAttributes object and pass the path of that ImageAttributes object (along with the path of an Image) to the DrawImage method.

The following example takes an image that is all one color (0.2, 0.0, 0.4, 1.0) and doubles the red component adds 0.2 to the red, green, and blue components

The following illustration shows the original image on the left and the transformed image on the right.

The code in the following example uses the following steps to perform the recoloring:

1. Initialize a ColorMatrix object.

2. Create an ImageAttributes object and pass the ColorMatrix object to the SetColorMatrix method of the ImageAttributes object.

3. Pass the ImageAttributes object to the DrawImage method of a Graphics object.

Image image = new Bitmap("InputColor.bmp");
ImageAttributes imageAttributes = new ImageAttributes();
int width = image.Width;
int height = image.Height;

float[][] colorMatrixElements = { 
   new float[] {2,  0,  0,  0, 0},        // red scaling factor of 2
   new float[] {0,  1,  0,  0, 0},        // green scaling factor of 1
   new float[] {0,  0,  1,  0, 0},        // blue scaling factor of 1
   new float[] {0,  0,  0,  1, 0},        // alpha scaling factor of 1
   new float[] {.2f, .2f, .2f, 0, 1}};    // three translations of 0.2

ColorMatrix colorMatrix = new ColorMatrix(colorMatrixElements);

imageAttributes.SetColorMatrix(
   colorMatrix,
   ColorMatrixFlag.Default,
   ColorAdjustType.Bitmap);

e.Graphics.DrawImage(image, 10, 10);

e.Graphics.DrawImage(
   image,
   new Rectangle(120, 10, width, height),  // destination rectangle 
   0, 0,        // upper-left corner of source rectangle 
   width,       // width of source rectangle
   height,      // height of source rectangle
   GraphicsUnit.Pixel,
   imageAttributes);

.NET Framework

.NET Framework Client Profile

Windows 8 Consumer Preview, Windows Server 8 Beta, Windows 7, Windows Server 2008 SP2, Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Reference

Other Resources