static void Main( )
{
// Load the input image.
Write("Enter file name: ");
string pathIn = ReadLine();
Retina retina = new Retina(pathIn + ".png");
Retina outputRetina = new Retina(pathIn + ".png");
for (int row = 1; row < retina.Pixels.GetLength(0) - 1; row++)
{
for (int col = 1; col < retina.Pixels.GetLength(1) - 1; col++)
{
int red = Convolution(row, col, "red", retina);
int green = Convolution(row, col, "green", retina);
int blue = Convolution(row, col, "blue", retina);
outputRetina.Pixels[row, col] = SD.Color.FromArgb(red, green, blue); // Original image is not modified
}
}
// Store the resulting image.
string pathOut = pathIn + "_output.png";
outputRetina.SaveToFile(pathOut);
}
static int Convolution(int row, int col, string colour, Retina retina)
{
int[,] kernel_1 =
{
{ 5, 5, 5 },
{ -3, 0, -3 },
{ -3, -3, -3 }
};
int[,] kernel_2 =
{
{ -3, 5, 5 },
{ -3, 0, 5 },
{ -3, -3, -3 }
};
int[] convolutionValues = new int[8]; // Array to store the sums of convolution
switch (colour)
{
case "red":
for (int convolution = 0; convolution < 8; convolution += 2)
{
int sum1 = 0;
int sum2 = 0;
sum1 += retina.Pixels[row - 1, col - 1].R * kernel_1[0, 0];
sum1 += retina.Pixels[row - 1, col].R * kernel_1[0, 1];
sum1 += retina.Pixels[row - 1, col + 1].R * kernel_1[0, 2];
sum1 += retina.Pixels[row, col - 1].R * kernel_1[1, 0];
sum1 += retina.Pixels[row, col + 1].R * kernel_1[1, 2];
sum1 += retina.Pixels[row + 1, col - 1].R * kernel_1[2, 0];
sum1 += retina.Pixels[row + 1, col].R * kernel_1[2, 1];
sum1 += retina.Pixels[row + 1, col + 1].R * kernel_1[2, 2];
sum2 += retina.Pixels[row - 1, col - 1].R * kernel_2[0, 0];
sum2 += retina.Pixels[row - 1, col].R * kernel_2[0, 1];
sum2 += retina.Pixels[row - 1, col + 1].R * kernel_2[0, 2];
sum2 += retina.Pixels[row, col - 1].R * kernel_2[1, 0];
sum2 += retina.Pixels[row, col + 1].R * kernel_2[1, 2];
sum2 += retina.Pixels[row + 1, col - 1].R * kernel_2[2, 0];
sum2 += retina.Pixels[row + 1, col].R * kernel_2[2, 1];
sum2 += retina.Pixels[row + 1, col + 1].R * kernel_2[2, 2];
convolutionValues[convolution] = sum1;
convolutionValues[convolution + 1] = sum2;
kernel_1 = RotateKernel(kernel_1);
kernel_2 = RotateKernel(kernel_2);
}
break;
case "green":
for (int convolution = 0; convolution < 8; convolution += 2)
{
int sum1 = 0;
int sum2 = 0;
sum1 += retina.Pixels[row - 1, col - 1].G * kernel_1[0, 0];
sum1 += retina.Pixels[row - 1, col].G * kernel_1[0, 1];
sum1 += retina.Pixels[row - 1, col + 1].G * kernel_1[0, 2];
sum1 += retina.Pixels[row, col - 1].G * kernel_1[1, 0];
sum1 += retina.Pixels[row, col + 1].G * kernel_1[1, 2];
sum1 += retina.Pixels[row + 1, col - 1].G * kernel_1[2, 0];
sum1 += retina.Pixels[row + 1, col].G * kernel_1[2, 1];
sum1 += retina.Pixels[row + 1, col + 1].G * kernel_1[2, 2];
sum2 += retina.Pixels[row - 1, col - 1].G * kernel_2[0, 0];
sum2 += retina.Pixels[row - 1, col].G * kernel_2[0, 1];
sum2 += retina.Pixels[row - 1, col + 1].G * kernel_2[0, 2];
sum2 += retina.Pixels[row, col - 1].G * kernel_2[1, 0];
sum2 += retina.Pixels[row, col + 1].G * kernel_2[1, 2];
sum2 += retina.Pixels[row + 1, col - 1].G * kernel_2[2, 0];
sum2 += retina.Pixels[row + 1, col].G * kernel_2[2, 1];
sum2 += retina.Pixels[row + 1, col + 1].G * kernel_2[2, 2];
convolutionValues[convolution] = sum1;
convolutionValues[convolution + 1] = sum2;
kernel_1 = RotateKernel(kernel_1);
kernel_2 = RotateKernel(kernel_2);
}
break;
case "blue":
for (int convolution = 0; convolution < 8; convolution += 2)
{
int sum1 = 0;
int sum2 = 0;
sum1 += retina.Pixels[row - 1, col - 1].B * kernel_1[0, 0];
sum1 += retina.Pixels[row - 1, col].B * kernel_1[0, 1];
sum1 += retina.Pixels[row - 1, col + 1].B * kernel_1[0, 2];
sum1 += retina.Pixels[row, col - 1].B * kernel_1[1, 0];
sum1 += retina.Pixels[row, col + 1].B * kernel_1[1, 2];
sum1 += retina.Pixels[row + 1, col - 1].B * kernel_1[2, 0];
sum1 += retina.Pixels[row + 1, col].B * kernel_1[2, 1];
sum1 += retina.Pixels[row + 1, col + 1].B * kernel_1[2, 2];
sum2 += retina.Pixels[row - 1, col - 1].B * kernel_2[0, 0];
sum2 += retina.Pixels[row - 1, col].B * kernel_2[0, 1];
sum2 += retina.Pixels[row - 1, col + 1].B * kernel_2[0, 2];
sum2 += retina.Pixels[row, col - 1].B * kernel_2[1, 0];
sum2 += retina.Pixels[row, col + 1].B * kernel_2[1, 2];
sum2 += retina.Pixels[row + 1, col - 1].B * kernel_2[2, 0];
sum2 += retina.Pixels[row + 1, col].B * kernel_2[2, 1];
sum2 += retina.Pixels[row + 1, col + 1].B * kernel_2[2, 2];
convolutionValues[convolution] = sum1;
convolutionValues[convolution + 1] = sum2;
kernel_1 = RotateKernel(kernel_1);
kernel_2 = RotateKernel(kernel_2);
}
break;
default:
return(0);
break;
}
int maxSum = convolutionValues.Max();
if (maxSum > 255)
{
return(255);
}
else if (maxSum < 0)
{
return(0);
}
else
{
return(maxSum);
}
}
