public List <DetectedCard> Detect(Bitmap bitmap, out Bitmap detectionImage)
{
var imageTools = new ImageTools();
var detectedCards = new List <DetectedCard>();
// Greyscale
var greyscaleImage = imageTools.GreyscaleEdgeDetectionImage(bitmap);
var bitmapData = greyscaleImage.LockBits(
new Rectangle(0, 0, greyscaleImage.Width, greyscaleImage.Height),
ImageLockMode.ReadWrite, greyscaleImage.PixelFormat);
var blobCounter = new BlobCounter
{
FilterBlobs = true,
MinHeight = Convert.ToInt32(BlobHeight * scaleFactor),
MinWidth = Convert.ToInt32(BlobWidth * scaleFactor)
};
blobCounter.ProcessImage(bitmapData);
var blobs = blobCounter.GetObjectsInformation();
greyscaleImage.UnlockBits(bitmapData);
var shapeChecker = new SimpleShapeChecker();
var cardPositions = new List <IntPoint>();
// Loop through detected shapes
for (var i = 0; i < blobs.Length; i++)
{
var edgePoints = blobCounter.GetBlobsEdgePoints(blobs[i]);
// is triangle or quadrilateral
if (!shapeChecker.IsConvexPolygon(edgePoints, out var corners))
{
continue;
}
var subType = shapeChecker.CheckPolygonSubType(corners);
// Only return 4 corner rectanges
if (subType != PolygonSubType.Parallelogram && subType != PolygonSubType.Rectangle ||
corners.Count != 4)
{
continue;
}
corners = RotateCard(corners);
// Prevent it from detecting the same card twice
if (cardPositions.Any(point => corners[0].DistanceTo(point) < Convert.ToInt32(40 * scaleFactor)))
{
continue;
}
// Hack to prevent it from detecting smaller sections of the card instead of the whole card
if (GetArea(corners) < Convert.ToInt32(DetectionThreshold * scaleFactor))
{
continue;
}
cardPositions.Add(corners[0]);
var cardBitmap = imageTools.GetDetectedCardImage(corners, bitmap, scaleFactor);
var card = new DetectedCard
{
Corners = corners,
CardBitmap = cardBitmap
};
detectedCards.Add(card);
}
detectionImage = greyscaleImage;
return(detectedCards);
}
public IdentifiedCard(DetectedCard detectedCard, Card bestMatch)
{
Card = bestMatch;
Corners = detectedCard.Corners;
}