private static List <EllipticalFit> AddWithoutOverlap(List <EllipticalFit> ellipseList, EllipticalFit fit)
{
List <EllipticalFit> outList = new List <EllipticalFit>();
if (ellipseList.Count == 0)
{
outList.Add(fit);
return(outList);
}
else
{
bool addFit = true;
for (int i = 0; i < ellipseList.Count; i++)
{
if (ellipseList[i].BoundingRectangle().IntersectsWith(fit.BoundingRectangle()))
{
// In case over overlap: only add the best one
if (ellipseList[i].DifferenceFromCircle < fit.DifferenceFromCircle)
{
addFit = false;
outList.Add(ellipseList[i]);
}
}
else // Add both
{
outList.Add(ellipseList[i]);
}
}
if (addFit)
{
outList.Add(fit);
}
return(outList);
}
}
private static List <EllipticalFit> FindPointsByCanny(int numberToFind,
int currentCross, byte[,] cannyData, int searchSize, ref int searchShift, ref int attempt, ref bool ellipsesValid)
{
searchSize = (int)(Math.Round((double)searchSize / 2) * 2); // has to be even
int shiftX = searchShift == 1 || searchShift == 3 ? (int)(searchSize / 4) : 0;
int shiftY = searchShift == 2 || searchShift == 3 ? (int)(searchSize / 4) : 0;
int searchJump = searchSize / 2;
int w = cannyData.GetLength(0);
int h = cannyData.GetLength(1);
// Create a list with areas to look => cannot be reused due to (even very small) differences in size of scans
List <Point> searchPoints = new List <Point>();
for (int x = shiftX; x < w; x += searchJump)
{
int searchX = x;
if (x + searchSize >= w)
{
searchX = w - searchSize;
x = w;
}
for (int y = shiftY; y < h; y += searchJump)
{
int searchY = y;
if (y + searchSize >= h)
{
searchY = h - searchSize;
y = h;
}
searchPoints.Add(new Point(searchX, searchY));
}
}
// Assumed that the paper is oriented right => faster
searchPoints.Sort(delegate(Point p1, Point p2) { return(Math.Min(w - p1.X, h - p1.Y).CompareTo(Math.Min(w - p2.X, h - p2.Y))); });
/*
*
*
*
*
********
*/
#if DEBUG
var img = Processing.ByteToImage(cannyData);
#endif
// Crop small rectangles from canny
List <EllipticalFit> ellipseList = new List <EllipticalFit>();
for (int i = 0; i < searchPoints.Count; i++)
{
// Fit an ellipse
EllipticalFit fit = null;
RectangleF boundingRectangle = new RectangleF();
try
{
var searchRectangle = new Rectangle(searchPoints[i].X, searchPoints[i].Y, searchSize, searchSize);
fit = new EllipticalFit(cannyData, 255, searchRectangle);
#if DEBUG
using (Graphics g = Graphics.FromImage(img))
{
g.DrawRectangle(new Pen(Color.Yellow), searchRectangle);
}
#endif
// Empty search areas are already ignored in fit
boundingRectangle = fit.BoundingRectangle();
// If a valid ellipse is found
if (!double.IsNaN(boundingRectangle.X) && boundingRectangle.X > 0 &&
!double.IsNaN(boundingRectangle.Y) && boundingRectangle.Y > 0 &&
boundingRectangle.Width < searchSize && boundingRectangle.Height < searchSize &&
boundingRectangle.Width > .25 * searchSize && boundingRectangle.Height > .25 * searchSize &&
boundingRectangle.Width > 15 && boundingRectangle.Height > 15)
{
var observed = Processing.Crop(cannyData, searchRectangle);
var moments = Processing.Moments(observed);
double squareness = Math.Min((double)boundingRectangle.Width, (double)boundingRectangle.Height) / Math.Max((double)boundingRectangle.Width, (double)boundingRectangle.Height);
// Ellipse has to be more or less round, based on enough points and have some variance in each direction
if (squareness > .9 && moments[0] >= 8 && moments[3] > 0 && moments[4] > 0)
{
// Fill the ellipse with floodfill
var observedFilled = Processing.FloodFill(observed, 1, new PointF(
boundingRectangle.X - searchRectangle.X + (boundingRectangle.Width / 2),
boundingRectangle.Y - searchRectangle.Y + (boundingRectangle.Height / 2)));
var momentsFilled = Processing.Moments(observedFilled);
if (momentsFilled[1] > (boundingRectangle.Width / 2) && momentsFilled[1] < searchRectangle.Width - (boundingRectangle.Width / 2) &&
momentsFilled[2] > (boundingRectangle.Height / 2) && momentsFilled[2] < searchRectangle.Height - (boundingRectangle.Height / 2))
{
// Create a white circle of similar size
var expectedFilled = Processing.WhiteCircle(observedFilled.GetLength(0), observedFilled.GetLength(1), new RectangleF(
boundingRectangle.X - searchRectangle.X, boundingRectangle.Y - searchRectangle.Y, boundingRectangle.Width, boundingRectangle.Height));
// Compare the result of the floodfill with the white circle
fit.DifferenceFromCircle = Processing.AverageDifference(observedFilled, expectedFilled);
// Only if ellipse was closed they will be similar
if (fit.DifferenceFromCircle < .1)
{
ellipseList = AddWithoutOverlap(ellipseList, fit);
}
}
}
}
}
catch (Exception ex)
{
Logger.LogLow(ex.Message);
}
if (ellipseList.Count == numberToFind)
{
break;
}
}
ellipsesValid = EllipsePointsAreValid(Program.Test, ellipseList); // Count and colinearity have to be correct
/*
* using (Graphics g = Graphics.FromImage(img))
* {
* for (int i = 0; i < ellipseList.Count; i++)
* {
* g.DrawLine(new Pen(Color.Blue, 2), ellipseList[i].MidPoint().X - 15, ellipseList[i].MidPoint().Y, ellipseList[i].MidPoint().X + 15, ellipseList[i].MidPoint().Y);
* g.DrawLine(new Pen(Color.Blue, 2), ellipseList[i].MidPoint().X, ellipseList[i].MidPoint().Y - 15, ellipseList[i].MidPoint().X, ellipseList[i].MidPoint().Y + 15);
* }
* }
* img.Save(Program.UserSettings.defaultDirectory + "\\img\\"
+ Convert.ToString(DateTime.Now.Minute)
+ " - " + Convert.ToString(DateTime.Now.Second)
+ " - " + Convert.ToString(DateTime.Now.Millisecond)
+ " - " + currentCross
+ " - " + searchSize
+ " - " + searchShift
+ " - " + attempt
+ " - " + ellipseList.Count
+ " - " + ellipsesValid
+ ".bmp");
*/
Logger.LogHigh(
"Attempt:\t" + attempt +
"\tCanny:\t" + currentCross +
"\tSearch size:\t" + searchSize +
"\tSearch shift:\t" + searchShift +
"\tEllipses found:\t" + ellipseList.Count +
"\tEllipses valid:\t" + ellipsesValid);
// If not all ellipses are found, retry with shifted searcharea
if (ellipseList.Count != numberToFind && searchShift < 3)
{
searchShift++;
attempt++;
ellipseList = FindPointsByCanny(numberToFind, currentCross, cannyData, searchSize, ref searchShift, ref attempt, ref ellipsesValid);
}
return(ellipseList);
}