private OpenCV.Core.Point[] FindBiggestContourWithFourBorders(IList <MatOfPoint> contours)
{
OpenCV.Core.Point[] biggestContour = null;
Parallel.ForEach(contours, (c) =>
{
MatOfPoint2f mat2f = new MatOfPoint2f(c.ToArray());
double perimeter = Imgproc.ArcLength(mat2f, true);
if (perimeter > 1500)
{
MatOfPoint2f approx = new MatOfPoint2f();
Imgproc.ApproxPolyDP(mat2f, approx, 0.02 * perimeter, true);
if (approx.Total() == 4)
{
MatOfPoint approxMat = new MatOfPoint(approx.ToArray());
if (Imgproc.IsContourConvex(approxMat))
{
if (biggestContour == null)
{
biggestContour = approx.ToArray();
detectedBorder = approx;
oldPerimeter = perimeter;
}
else
{
if (oldPerimeter < perimeter)
{
biggestContour = approx.ToArray();
detectedBorder = approx;
oldPerimeter = perimeter;
}
}
}
}
}
mat2f.Dispose();
});
return(biggestContour);
}