public static Dictionary <Point, MinutiaeType> DetectMinutiae(WriteableBitmap bitmap)
{
Dictionary <Point, MinutiaeType> points = new Dictionary <Point, MinutiaeType>();
using (BitmapContext context = bitmap.GetBitmapContext())
{
int width = context.Width;
int height = context.Height;
int[] mask = new int[9];
for (int x = 1; x < width - 1; ++x)
{
for (int y = 1; y < height - 1; ++y)
{
if (PixelHelper.IsBlack(context, x, y))
{
mask[0] = PixelHelper.IsWhite(context, x, y + 1) ? 0 : 1;
mask[1] = PixelHelper.IsWhite(context, x - 1, y + 1) ? 0 : 1;
mask[2] = PixelHelper.IsWhite(context, x - 1, y) ? 0 : 1;
mask[3] = PixelHelper.IsWhite(context, x - 1, y - 1) ? 0 : 1;
mask[4] = PixelHelper.IsWhite(context, x, y - 1) ? 0 : 1;
mask[5] = PixelHelper.IsWhite(context, x + 1, y - 1) ? 0 : 1;
mask[6] = PixelHelper.IsWhite(context, x + 1, y) ? 0 : 1;
mask[7] = PixelHelper.IsWhite(context, x + 1, y + 1) ? 0 : 1;
mask[8] = mask[0];
MinutiaeType cn = CalculateCN(mask);
if (IsMinutiae(cn))
{
points.Add(new Point(x, y), cn);
if (cn == MinutiaeType.Point)
{
PixelHelper.SetPixel(context, x, y, Colors.Red);
}
else if (cn == MinutiaeType.Ending)
{
PixelHelper.SetPixel(context, x, y, Colors.Green);
}
else if (cn == MinutiaeType.Fork)
{
PixelHelper.SetPixel(context, x, y, Colors.Yellow);
}
else if (cn == MinutiaeType.Crossing)
{
PixelHelper.SetPixel(context, x, y, Colors.DeepPink);
}
}
}
}
}
}
return(points);
}
public static WriteableBitmap DilateAndErode(WriteableBitmap writeableBitmap, bool?[,] matrix3x3)
{
int width = writeableBitmap.PixelWidth;
int height = writeableBitmap.PixelHeight;
WriteableBitmap newImage = writeableBitmap.Clone();
using (BitmapContext newcontext = newImage.GetBitmapContext())
{
using (BitmapContext context = writeableBitmap.GetBitmapContext())
{
for (int x = 0; x < width; ++x)
{
for (int y = 0; y < height; ++y)
{
bool exaclyMatch = true;
for (int i = 0; i < 3; ++i)
{
for (int j = 0; j < 3; ++j)
{
bool?matVal = matrix3x3[i, j];
int cX = x - 1 + i;
int cY = y - 1 + j;
if (cX > 0 && cY > 0 && cX < width && cY < height && matVal != null)
{
if (!(PixelHelper.IsBlack(context, cX, cY) == matVal))
{
exaclyMatch = false;
goto ExitLoop;
}
}
}
}
ExitLoop:
if (exaclyMatch)
{
PixelHelper.SetBlack(newcontext, x, y);
}
else
{
PixelHelper.SetWhite(newcontext, x, y);
}
}
}
}
}
return(newImage);
}
private static int CalculateWeight(int i, int j, BitmapContext context)
{
int width = context.Width;
int height = context.Height;
int[] N = new int[] { 128, 1, 2, 64, 0, 4, 32, 16, 8 };
int weight = 0;
if (i - 1 > 0)
{
if (j - 1 > 0 && PixelHelper.IsBlack(context, i - 1, j - 1))
{
weight += N[0];
}
if (PixelHelper.IsBlack(context, i - 1, j))
{
weight += N[3];
}
if (j + 1 < height && PixelHelper.IsBlack(context, i - 1, j + 1))
{
weight += N[6];
}
}
if (i + 1 < width)
{
if (j - 1 > 0 && PixelHelper.IsBlack(context, i + 1, j - 1))
{
weight += N[2];
}
if (PixelHelper.IsBlack(context, i + 1, j))
{
weight += N[5];
}
if (j + 1 < height && PixelHelper.IsBlack(context, i + 1, j + 1))
{
weight += N[8];
}
}
if (j - 1 > 0 && PixelHelper.IsBlack(context, i, j - 1))
{
weight += N[1];
}
if (j + 1 < height && PixelHelper.IsBlack(context, i, j + 1))
{
weight += N[7];
}
return(weight);
}
private static int[,] PixelInfo(BitmapContext context)
{
int width = context.Width;
int height = context.Height;
int[,] pixels = new int[width, height];
for (int i = 0; i < width; ++i)
{
for (int j = 0; j < height; ++j)
{
if (PixelHelper.IsBlack(context, i, j))
{
pixels[i, j] = 1;
}
else
{
pixels[i, j] = 0;
}
}
}
return(pixels);
}