private bool Detect(Mat bin)
{
// Reset
mRects.Clear();
// Find contours
Mat hierarchy = new Mat();
IList <MatOfPoint> contoursList = new JavaList <MatOfPoint>();
Imgproc.FindContours(bin.Clone(), contoursList, hierarchy, Imgproc.RetrTree, Imgproc.ChainApproxSimple);
// Filter contours
bool detected = false;
for (int iContour = 0; iContour < contoursList.Count(); iContour++)
{
// Areas
Core.Rect rect = Imgproc.BoundingRect(contoursList[iContour]);
double ellipseArea = PI * (rect.Width / 2) * (rect.Height / 2);
double area = Imgproc.ContourArea(contoursList[iContour]);
// Ratios
double boundWidthPerHeight = (double)rect.Width / rect.Height;
double areaPerEllipse = (double)(area) / ellipseArea;
double rectPerFrame = (double)(rect.Area()) / (bin.Size().Width *bin.Size().Height);
// Check constraints
if (rectPerFrame > MIN_SIGN_SIZE_PER_FRAME)
{
if (1 - LIMIT_DIF_SIGN_SIZE < boundWidthPerHeight && boundWidthPerHeight < 1 + LIMIT_DIF_SIGN_SIZE)
{
if (1 - LIMIT_DIF_SIGN_AREA < areaPerEllipse && areaPerEllipse < 1 + LIMIT_DIF_SIGN_AREA)
{
mRects.Add(rect);
detected = true;
}
}
}
}
return(detected);
}