public static Bitmap Negative(Bitmap bmp)
{
Bitmap retBmp = new Bitmap(bmp.Width, bmp.Height);
using (var bl = new BitmapLocker(bmp))
using (var rbl = new BitmapLocker(retBmp))
{
unsafe
{
for (int y = 0; y < bmp.Height; y++)
{
for (int x = 0; x < bmp.Width; x++)
{
byte *oldPixel = bl.GetPixelPtr(x, y);
byte *newPixel = rbl.GetPixelPtr(x, y);
for (int i = 0; i < 3; i++)
{
newPixel[i] = (byte)(255 - oldPixel[i]);
}
newPixel[3] = 255;
}
}
}
}
return(retBmp);
}
public static Bitmap PowerLawTransform(double c, double gamma, Bitmap bmp)
{
Bitmap retBmp = new Bitmap(bmp.Width, bmp.Height);
using (var bl = new BitmapLocker(bmp))
using (var rbl = new BitmapLocker(retBmp))
{
unsafe
{
for (int y = 0; y < bmp.Height; y++)
{
for (int x = 0; x < bmp.Width; x++)
{
byte *oldPixel = bl.GetPixelPtr(x, y);
byte *newPixel = rbl.GetPixelPtr(x, y);
for (int i = 0; i < 3; i++)
{
double val = c * Math.Pow(oldPixel[i], gamma);
if (val < 0)
{
val = 0;
}
if (val > 255)
{
val = 255;
}
newPixel[i] = (byte)(Math.Round(val));
}
newPixel[3] = 255;
}
}
}
}
return(retBmp);
}