public double[,] ProcessPictureAlpha0(ImageLoader loader)
{
var image = (Bitmap)loader.Image;
var transform = new Tranformation();
double[,] mask = transform.CreateLaplacianFilter(0);
return(transform.ProcessMaskDouble(image, mask, false));
}
using System;
using System.Drawing;
using ImageFilter.Extensions;
namespace ImageFilter.Filters
{
public class SobelFilter : IPictureProcessor
{
double[,] maskV = {
{ 1, 2, 1 },
{ 0, 0, 0 },
{ -1, -2, -1 }
};
double[,] maskH = {
{ -1, 0, 1 },
{ -2, 0, 2 },
{ -1, 0, 1 }
};
private int v;
private Bitmap processPicture;
public SobelFilter(int v)
{
this.v = v;
}
public double[,] Get(ImageLoader loader)
{
var image = (Bitmap)loader.Image;
var transform = new Tranformation();
double[,] mask = v == 1 ? maskV : maskH;
return transform.ProcessMaskDouble(image, mask, false);
}
public Bitmap ProcessPicture(ImageLoader loader)
{
var image = (Bitmap)loader.Image;
var transform = new Tranformation();
double[,] mask = v == 1 ? maskV : maskH;
processPicture = transform.ProcessMask(image, mask, false);
return processPicture;
}
public static double[,] CalculateGradient(double[,] Gv, double[,] Gh)
{
int height = Gv.GetLength(0);
int width = Gv.GetLength(1);
double[,] result = new double[height, width];
for (var y = 0; y < height; y++)
{
for (var x = 0; x < width; x++)
{
double gv = Gv[y, x];
double gh = Gh[y, x];
var res = Math.Sqrt(Math.Pow(gv, 2) + Math.Pow(gh, 2));
result[y, x] = res;
}
}
return result;
}
public static double[,] CalculateGradientDirection(double[,] Gv, double[,] Gh)
{
int height = Gv.GetLength(0);
int width = Gv.GetLength(1);
double[,] result = new double[height, width];
for (var y = 0; y < height; y++)
{
for (var x = 0; x < width; x++)
{
double gv = Gv[y, x];
double gh = Gh[y, x];
var res = Math.Atan2(gv, gh) * (180.0 / Math.PI);
result[y, x] = res;
}
}
return result;
}
public static Bitmap GetColorMap(double[,] Gv, double[,] Gh)
{
Bitmap result = new Bitmap(Gv.GetLength(0), Gv.GetLength(1));
var direction = CalculateGradientDirection(Gv, Gh);
for (var y = 0; y < direction.GetLength(0); y++)
{
for (var x = 0; x < direction.GetLength(1); x++)
{
double blue;
double green;
double red = green = blue = 0;
if (direction[y, x] <= -90 && direction[y, x] >= -180)
{
// Red
red = 255;
} else if (direction[y, x] <= 0 && direction[y, x] > -90)
{
// Green
green = 255;
} else if (direction[y, x] <= 90 && direction[y, x] > 0)
{
// Blue
blue = 255;
} else
{
red = 255;
green = 255;
blue = 255;
}
Color destinationColor = Color.FromArgb(
Convert.ToByte(red.Clamp(0, 255)),
Convert.ToByte(green.Clamp(0, 255)),
Convert.ToByte(blue.Clamp(0, 255)));
result.SetPixel(x, y, destinationColor);
}
}
return result;
}
public static Bitmap GetBinaryCard(int thr, double[,] Gv, double[,] Gh)
{
Bitmap result = new Bitmap(Gv.GetLength(0), Gv.GetLength(1));
var gradient = CalculateGradient(Gv, Gh);
for (var y = 0; y < gradient.GetLength(0); y++)
{
for (var x = 0; x < gradient.GetLength(1); x++)
{
double blue;
double green;
double red = green = blue = 0;
if (gradient[y, x] > thr)
{
red = green = blue = 255;
} else
{
red = green = blue = 0;
}
Color destinationColor = Color.FromArgb(
Convert.ToByte(red.Clamp(0, 255)),
Convert.ToByte(green.Clamp(0, 255)),
Convert.ToByte(blue.Clamp(0, 255)));
result.SetPixel(x, y, destinationColor);
}
}
return result;
}
}
}