List<Point> FindMinutiae(BinaryMap binary) { List<Point> result = new List<Point>(); for (int y = 0; y < binary.Height; ++y) for (int x = 0; x < binary.Width; ++x) if (binary.GetBit(x, y) && IsMinutia[binary.GetNeighborhood(x, y)]) result.Add(new Point(x, y)); return result; }
static bool IsFalseEnding(BinaryMap binary, Point ending) { foreach (Point relativeNeighbor in Neighborhood.CornerNeighbors) { Point neighbor = Calc.Add(ending, relativeNeighbor); if (binary.GetBit(neighbor)) return Calc.CountBits(binary.GetNeighborhood(neighbor)) > 2; } return false; }
public BinaryMap Thin(BinaryMap input) { BinaryMap intermediate = new BinaryMap(input.Size); intermediate.Copy(input, new RectangleC(1, 1, input.Width - 2, input.Height - 2), new Point(1, 1)); BinaryMap border = new BinaryMap(input.Size); BinaryMap skeleton = new BinaryMap(input.Size); bool removedAnything = true; for (int i = 0; i < MaxIterations && removedAnything; ++i) { removedAnything = false; for (int j = 0; j < 4; ++j) { border.Copy(intermediate); switch (j) { case 0: border.AndNot(intermediate, new RectangleC(1, 0, border.Width - 1, border.Height), new Point(0, 0)); break; case 1: border.AndNot(intermediate, new RectangleC(0, 0, border.Width - 1, border.Height), new Point(1, 0)); break; case 2: border.AndNot(intermediate, new RectangleC(0, 1, border.Width, border.Height - 1), new Point(0, 0)); break; case 3: border.AndNot(intermediate, new RectangleC(0, 0, border.Width, border.Height - 1), new Point(0, 1)); break; } border.AndNot(skeleton); for (int odd = 0; odd < 2; ++odd) Parallel.For(1, input.Height - 1, delegate(int y) { if (y % 2 == odd) for (int xw = 0; xw < input.WordWidth; ++xw) if (border.IsWordNonZero(xw, y)) for (int x = xw << BinaryMap.WordShift; x < (xw << BinaryMap.WordShift) + BinaryMap.WordSize; ++x) if (x > 0 && x < input.Width - 1 && border.GetBit(x, y)) { uint neighbors = intermediate.GetNeighborhood(x, y); if (IsRemovable[neighbors] || IsEnding[neighbors] && IsFalseEnding(intermediate, new Point(x, y))) { removedAnything = true; intermediate.SetBitZero(x, y); } else skeleton.SetBitOne(x, y); } }); } } Logger.Log(skeleton); return skeleton; }