private Location GetBlobEdgeLocation(Point point)
{
bool isBlob = CanRead(point) && Read(point) == 1;
if (!isBlob)
{
return(default(Location));
}
Location location = new Location {
Top = point.X,
Left = point.Y,
Bottom = point.X,
Right = point.Y
};
Location upBlobLocation = GetBlobEdgeLocation(new Point(point.X - 1, point.Y));
BlobDetectionResult.Merge(ref location, ref upBlobLocation);
Location rightBlobLocation = GetBlobEdgeLocation(new Point(point.X, point.Y + 1));
BlobDetectionResult.Merge(ref location, ref rightBlobLocation);
Location downBlobLocation = GetBlobEdgeLocation(new Point(point.X + 1, point.Y));
BlobDetectionResult.Merge(ref location, ref downBlobLocation);
Location leftBlobLocation = GetBlobEdgeLocation(new Point(point.X, point.Y - 1));
BlobDetectionResult.Merge(ref location, ref leftBlobLocation);
return(location);
}
private Location TraceContour(Point currentPosition, int previousContourPoint)
{
Location location = new Location {
Top = currentPosition.X,
Left = currentPosition.Y,
Bottom = currentPosition.X,
Right = currentPosition.Y
};
int startContourPoint = (previousContourPoint + 2) % MaxNeighboringPoints;
int currentContourPoint = startContourPoint;
for (int i = 0; i < 8; i++)
{
currentContourPoint = (startContourPoint + i) % MaxNeighboringPoints;
Point nextPosition = CalculateNextPosition(currentPosition, currentContourPoint);
if (!CanRead(nextPosition))
{
continue;
}
if (ContourClosed(currentPosition, nextPosition))
{
break;
}
if (Read(nextPosition) == 1)
{
int relativeContourPoint = (currentContourPoint + (MaxNeighboringPoints / 2)) % MaxNeighboringPoints;
Location nextBlobLocation = TraceContour(
nextPosition,
previousContourPoint: relativeContourPoint
);
BlobDetectionResult.Merge(ref location, ref nextBlobLocation);
break;
}
}
return(location);
}
