private Bitmap ConvertToSepia(Bitmap bitmap)
{
ColorMatrix cm = new ColorMatrix(new float[][] {
new float[] { 0.393f, 0.349f, 0.272f, 0, 0 },
new float[] { 0.769f, 0.686f, 0.534f, 0, 0 },
new float[] { 0.189f, 0.168f, 0.131f, 0, 0 },
new float[] { 0, 0, 0, 1, 0 },
new float[] { 0, 0, 0, 0, 1 }
});
return(ImageHelper.ApplyColorMatrix(bitmap, cm));
}
protected Bitmap Warm(Bitmap bitmap, float val)
{
ColorMatrix cm = new ColorMatrix(new float[][] {
new float[] { 1, 0, 0, 0, 0 },
new float[] { 0, 1, 0, 0, 0 },
new float[] { 0, 0, 1, 0, 0 },
new float[] { 0, 0, 0, 1, 0 },
new float[] { val, 0, -val, 0, 1 }
});
return(ImageHelper.ApplyColorMatrix(bitmap, cm));
}
public static Bitmap AdjustBrightness(float bf, float cf, Bitmap bitmap)
{
ColorMatrix bm = new ColorMatrix(new float[][] {
new float[] { 1f, 0f, 0f, 0f, 0f },
new float[] { 0f, 1f, 0f, 0f, 0f },
new float[] { 0f, 0f, 1f, 0f, 0f },
new float[] { 0f, 0f, 0f, 1f, 0f },
new float[] { bf, bf, bf, 1f, 1f }
});
//Create the contrast matrix. Note, the last row offsets the colors by .001 to avoid
//arithmetic overflows that cause dramatically incorrect colors.
//Thanks to Bob Powell for that tip: http://www.bobpowell.net/image_contrast.htm
ColorMatrix cm = new ColorMatrix(new float[][] {
new float[] { cf, 0f, 0f, 0f, 0f },
new float[] { 0f, cf, 0f, 0f, 0f },
new float[] { 0f, 0f, cf, 0f, 0f },
new float[] { 0f, 0f, 0f, 1f, 0f },
new float[] { 0.001f, 0.001f, 0.001f, 0f, 1f }
});
ColorMatrix adjust = null;
if (bf != 0)
{
adjust = bm;
}
if (cf != 1)
{
if (adjust != null)
{
adjust = ImageUtils.Multiply(adjust, cm);
}
else
{
adjust = cm;
}
}
if (adjust != null)
{
return(ImageHelper.ApplyColorMatrix(bitmap, adjust));
}
else
{
return(bitmap);
}
}
/// <summary>
/// Convert to a black and white image.
/// Based on image processing algorithm from Paul Haeberli.
/// http://www.sgi.com/misc/grafica/matrix/
/// </summary>
/// <param name="bitmap"></param>
private Bitmap ConvertToBlackAndWhite(Bitmap bitmap)
{
float rwgt = 0.3086f;
float gwgt = 0.6094f;
float bwgt = 0.0820f;
ColorMatrix cm = new ColorMatrix(new float[][] {
new float[] { rwgt, rwgt, rwgt, 0f, 0f },
new float[] { gwgt, gwgt, gwgt, 0f, 0f },
new float[] { bwgt, bwgt, bwgt, 0f, 0f },
new float[] { 0f, 0f, 0f, 1f, 0f },
new float[] { 0f, 0f, 0f, 0f, 1f }
});
return(ImageHelper.ApplyColorMatrix(bitmap, cm));
}
private Bitmap Saturate(Bitmap bitmap)
{
float a, b, c, d, e, f;
float saturation;
saturation = 1.65f;
a = (0.3086f * (1 - saturation)) + saturation;
b = (0.3086f * (1 - saturation));
c = (0.6094f * (1 - saturation));
d = (0.6094f * (1 - saturation)) + saturation;
e = (0.0820f * (1 - saturation));
f = (0.0820f * (1 - saturation)) + saturation;
ColorMatrix cm = new ColorMatrix(new float[][] {
new float[] { a, b, b, 0, 0 },
new float[] { c, d, c, 0, 0 },
new float[] { e, e, f, 0, 0 },
new float[] { 0, 0, 0, 1, 0 },
new float[] { 0, 0, 0, 0, 1 }
});
return(ImageHelper.ApplyColorMatrix(bitmap, cm));
}
