public static Bitmap ToSepia(Bitmap source)
{
using (ColorMatrix saturation = new ColorMatrix())
using (ColorMatrix rgbFilter = new ColorMatrix())
{
saturation.SetSaturation(0f);
rgbFilter.SetScale(1.0f, 0.95f, 0.82f, 1.0f);
saturation.SetConcat(rgbFilter, saturation);
return(ColorSpaceTransformation.ToColorSpace(source, saturation));
}
}
void UpdateColorMatrix(float[][] rgbawMatrix)
{
var rOffset = rgbawMatrix[0][4];
var gOffset = rgbawMatrix[1][4];
var bOffset = rgbawMatrix[2][4];
var aOffset = rgbawMatrix[3][4];
_colorMatrix.SetScale(rOffset, gOffset, bOffset, aOffset);
var transposed = GetAndroidMatrix(rgbawMatrix);
_colorMatrix.Set(transposed);
}
public byte[] Sepia(byte[] image)
{
Bitmap bmpOriginal = ByteToBitmap(image);
int width, height, r, g, b, c, gry;
height = bmpOriginal.Height;
width = bmpOriginal.Width;
int depth = 20;
Bitmap bmpSephia = Bitmap.CreateBitmap(width, height, Bitmap.Config.Argb8888);
Canvas canvas = new Canvas(bmpSephia);
Paint paint = new Paint();
ColorMatrix cm = new ColorMatrix();
cm.SetScale(.3f, .3f, .3f, 1.0f);
ColorMatrixColorFilter f = new ColorMatrixColorFilter(cm);
paint.SetColorFilter(f);
canvas.DrawBitmap(bmpOriginal, 0, 0, paint);
for (int x = 0; x < width; x++)
{
for (int y = 0; y < height; y++)
{
c = bmpOriginal.GetPixel(x, y);
r = Android.Graphics.Color.GetRedComponent(c);
g = Android.Graphics.Color.GetGreenComponent(c);
b = Android.Graphics.Color.GetBlueComponent(c);
gry = (r + g + b) / 3;
r = g = b = gry;
r = r + (depth * 2);
g = g + depth;
if (r > 255)
{
r = 255;
}
if (g > 255)
{
g = 255;
}
bmpSephia.SetPixel(x, y, Android.Graphics.Color.Rgb(r, g, b));
}
}
byte[] sepiaimage = BitmaptoByte(bmpSephia);
return(sepiaimage);
}
