AForge成像在图像中找到矩形

Question

如果图像是在油漆中创建的，我可以找到矩形。 我无法在Sanp shot或Screen Shot中找到矩形

它无法识别快照图像中的矩形... 请帮助我

string path = "D:\\testc.png";
Bitmap image = (Bitmap)Bitmap.FromFile(path);

BlobCounter blobCounter = new BlobCounter();            
blobCounter.FilterBlobs = true;
blobCounter.MinHeight = 1;
blobCounter.MinWidth = 1;
blobCounter.ProcessImage(image);
Blob[] blobs = blobCounter.GetObjectsInformation();
var retcs = blobCounter.GetObjects(image,true);
SimpleShapeChecker shapeChecker = new SimpleShapeChecker(); 
foreach (var blob in blobs)
{
  List<IntPoint> edgePoints = blobCounter.GetBlobsEdgePoints(blob);
  List<IntPoint> cornerPoints;
  // use the shape checker to extract the corner points
  if (shapeChecker.IsQuadrilateral(edgePoints, out cornerPoints))
  {
     // only do things if the corners form a rectangle
     if (shapeChecker.CheckPolygonSubType(cornerPoints) == PolygonSubType.Rectangle)
     {
     // here i use the graphics class to draw an overlay, but you
     // could also just use the cornerPoints list to calculate your
     // x, y, width, height values.
     List<Point> Points = new List<Point>();
     foreach (var point in cornerPoints)
     {
       Points.Add(new Point(point.X, point.Y));
     }
     Graphics g = Graphics.FromImage(image);
     g.DrawPolygon(new Pen(Color.Red, 5.0f), Points.ToArray());
     image.Save("D:\\result.png");
     }
   }
 }