public StopSignDetector(IInputArray stopSignModel)
{
_detector = new SURF(500);
using (Mat redMask = new Mat())
{
GetRedPixelMask(stopSignModel, redMask);
_modelKeypoints = new VectorOfKeyPoint();
_modelDescriptors = new Mat();
_detector.DetectAndCompute(redMask, null, _modelKeypoints, _modelDescriptors, false);
if (_modelKeypoints.Size == 0)
throw new Exception("No image feature has been found in the stop sign model");
}
_modelDescriptorMatcher = new BFMatcher(DistanceType.L2);
_modelDescriptorMatcher.Add(_modelDescriptors);
_octagon = new VectorOfPoint(
new Point[]
{
new Point(1, 0),
new Point(2, 0),
new Point(3, 1),
new Point(3, 2),
new Point(2, 3),
new Point(1, 3),
new Point(0, 2),
new Point(0, 1)
});
}
public static void FindMatch(Mat modelImage, Mat observedImage, out long matchTime, out VectorOfKeyPoint modelKeyPoints, out VectorOfKeyPoint observedKeyPoints, VectorOfVectorOfDMatch matches, out Mat mask, out Mat homography)
{
int k = 2;
double uniquenessThreshold = 0.8;
double hessianThresh = 300;
Stopwatch watch;
homography = null;
modelKeyPoints = new VectorOfKeyPoint();
observedKeyPoints = new VectorOfKeyPoint();
#if !__IOS__
if ( CudaInvoke.HasCuda)
{
CudaSURF surfCuda = new CudaSURF((float) hessianThresh);
using (GpuMat gpuModelImage = new GpuMat(modelImage))
//extract features from the object image
using (GpuMat gpuModelKeyPoints = surfCuda.DetectKeyPointsRaw(gpuModelImage, null))
using (GpuMat gpuModelDescriptors = surfCuda.ComputeDescriptorsRaw(gpuModelImage, null, gpuModelKeyPoints))
using (CudaBFMatcher matcher = new CudaBFMatcher(DistanceType.L2))
{
surfCuda.DownloadKeypoints(gpuModelKeyPoints, modelKeyPoints);
watch = Stopwatch.StartNew();
// extract features from the observed image
using (GpuMat gpuObservedImage = new GpuMat(observedImage))
using (GpuMat gpuObservedKeyPoints = surfCuda.DetectKeyPointsRaw(gpuObservedImage, null))
using (GpuMat gpuObservedDescriptors = surfCuda.ComputeDescriptorsRaw(gpuObservedImage, null, gpuObservedKeyPoints))
//using (GpuMat tmp = new GpuMat())
//using (Stream stream = new Stream())
{
matcher.KnnMatch(gpuObservedDescriptors, gpuModelDescriptors, matches, k);
surfCuda.DownloadKeypoints(gpuObservedKeyPoints, observedKeyPoints);
mask = new Mat(matches.Size, 1, DepthType.Cv8U, 1);
mask.SetTo(new MCvScalar(255));
Features2DToolbox.VoteForUniqueness(matches, uniquenessThreshold, mask);
int nonZeroCount = CvInvoke.CountNonZero(mask);
if (nonZeroCount >= 4)
{
nonZeroCount = Features2DToolbox.VoteForSizeAndOrientation(modelKeyPoints, observedKeyPoints,
matches, mask, 1.5, 20);
if (nonZeroCount >= 4)
homography = Features2DToolbox.GetHomographyMatrixFromMatchedFeatures(modelKeyPoints,
observedKeyPoints, matches, mask, 2);
}
}
watch.Stop();
}
}
else
#endif
{
using (UMat uModelImage = modelImage.ToUMat(AccessType.Read))
using (UMat uObservedImage = observedImage.ToUMat(AccessType.Read))
{
SURF surfCPU = new SURF(hessianThresh);
//extract features from the object image
UMat modelDescriptors = new UMat();
surfCPU.DetectAndCompute(uModelImage, null, modelKeyPoints, modelDescriptors, false);
watch = Stopwatch.StartNew();
// extract features from the observed image
UMat observedDescriptors = new UMat();
surfCPU.DetectAndCompute(uObservedImage, null, observedKeyPoints, observedDescriptors, false);
BFMatcher matcher = new BFMatcher(DistanceType.L2);
matcher.Add(modelDescriptors);
matcher.KnnMatch(observedDescriptors, matches, k, null);
mask = new Mat(matches.Size, 1, DepthType.Cv8U, 1);
mask.SetTo(new MCvScalar(255));
Features2DToolbox.VoteForUniqueness(matches, uniquenessThreshold, mask);
int nonZeroCount = CvInvoke.CountNonZero(mask);
if (nonZeroCount >= 4)
{
nonZeroCount = Features2DToolbox.VoteForSizeAndOrientation(modelKeyPoints, observedKeyPoints,
matches, mask, 1.5, 20);
if (nonZeroCount >= 4)
homography = Features2DToolbox.GetHomographyMatrixFromMatchedFeatures(modelKeyPoints,
observedKeyPoints, matches, mask, 2);
}
watch.Stop();
}
}
matchTime = watch.ElapsedMilliseconds;
}
public Mat Calculate(Bitmap referenceBitmap, Bitmap currentBitmap)
{
Mat homography;
using (var detector = new SURF(threshold))
using (var model = new Image<Gray, byte>(referenceBitmap))
using (var modelMat = model.Mat.ToUMat(AccessType.Read))
using (var modelKeyPoints = new VectorOfKeyPoint())
using (var modelDescriptors = new UMat())
using (var observed = new Image<Gray, byte>(currentBitmap))
using (var observedMat = observed.Mat.ToUMat(AccessType.Read))
using (var observedKeyPoints = new VectorOfKeyPoint())
using (var observedDescriptors = new UMat())
using (var matcher = new BFMatcher(DistanceType.L2))
using (var matches = new VectorOfVectorOfDMatch())
{
detector.DetectAndCompute(modelMat, null, modelKeyPoints, modelDescriptors, false);
detector.DetectAndCompute(observedMat, null, observedKeyPoints, observedDescriptors, false);
matcher.Add(modelDescriptors);
matcher.KnnMatch(observedDescriptors, matches, k, null);
homography = TryFindHomography(modelKeyPoints, observedKeyPoints, matches);
}
return homography;
}
//Use EmguCV
private EmguType SURFFeatureDetect(Image<Gray, Byte> image, Image<Gray, Byte> mask=null)
{
const int hessianThresh = 300;
SURF siftCPU = new SURF(hessianThresh);
EmguType result = new EmguType();
UMat matImage = image.Mat.ToUMat(AccessType.Read);
//UMat matImage = cannyFrame.ToUMat(AccessType.Read);
//GFTTDetector gd = new GFTTDetector();
try
{
//gd.DetectAndCompute(matImage, null, result.KeyPoints, result.Descriptors, false);
siftCPU.DetectAndCompute(
matImage,
mask,
result.KeyPoints,
result.Descriptors,
false);
}
catch (Exception e)
{
_log.Error("Feature Detect Exception:" + e.Message);
}
return result;
}
public void TestSURFBlankImage()
{
SURF detector = new SURF(500);
Image<Gray, Byte> img = new Image<Gray, byte>(1024, 900);
VectorOfKeyPoint vp = new VectorOfKeyPoint();
Mat descriptors = new Mat();
detector.DetectAndCompute(img, null, vp, descriptors, false);
}
public void TestBOWKmeansTrainer()
{
Image<Gray, byte> box = EmguAssert.LoadImage<Gray, byte>("box.png");
SURF detector = new SURF(500);
VectorOfKeyPoint kpts = new VectorOfKeyPoint();
Mat descriptors = new Mat();
detector.DetectAndCompute(box, null, kpts, descriptors, false);
BOWKMeansTrainer trainer = new BOWKMeansTrainer(100, new MCvTermCriteria(), 3, CvEnum.KMeansInitType.PPCenters);
trainer.Add(descriptors);
Mat vocabulary = new Mat();
trainer.Cluster(vocabulary);
BFMatcher matcher = new BFMatcher(DistanceType.L2);
BOWImgDescriptorExtractor extractor = new BOWImgDescriptorExtractor(detector, matcher);
extractor.SetVocabulary(vocabulary);
Mat descriptors2 = new Mat();
extractor.Compute(box, kpts, descriptors2);
}
public void TestSURFDetector2()
{
//Trace.WriteLine("Size of MCvSURFParams: " + Marshal.SizeOf(typeof(MCvSURFParams)));
Image<Gray, byte> box = EmguAssert.LoadImage<Gray, byte>("box.png");
SURF detector = new SURF(400);
Stopwatch watch = Stopwatch.StartNew();
VectorOfKeyPoint vp1 = new VectorOfKeyPoint();
Mat descriptors1 = new Mat();
detector.DetectAndCompute(box, null, vp1, descriptors1, false);
watch.Stop();
EmguAssert.WriteLine(String.Format("Time used: {0} milliseconds.", watch.ElapsedMilliseconds));
watch.Reset();
watch.Start();
MKeyPoint[] keypoints = detector.Detect(box, null);
//ImageFeature<float>[] features2 = detector.Compute(box, keypoints);
watch.Stop();
EmguAssert.WriteLine(String.Format("Time used: {0} milliseconds.", watch.ElapsedMilliseconds));
watch.Reset();
watch.Start();
//MCvSURFParams p = detector.SURFParams;
//SURFFeature[] features3 = box.ExtractSURF(ref p);
//watch.Stop();
//EmguAssert.WriteLine(String.Format("Time used: {0} milliseconds.", watch.ElapsedMilliseconds));
// EmguAssert.IsTrue(features1.Length == features2.Length);
//EmguAssert.IsTrue(features2.Length == features3.Length);
PointF[] pts =
#if NETFX_CORE
Extensions.
#else
Array.
#endif
ConvertAll<MKeyPoint, PointF>(keypoints, delegate(MKeyPoint mkp)
{
return mkp.Point;
});
//SURFFeature[] features = box.ExtractSURF(pts, null, ref detector);
//int count = features.Length;
/*
for (int i = 0; i < features1.Length; i++)
{
Assert.AreEqual(features1[i].KeyPoint.Point, features2[i].KeyPoint.Point);
float[] d1 = features1[i].Descriptor;
float[] d2 = features2[i].Descriptor;
for (int j = 0; j < d1.Length; j++)
Assert.AreEqual(d1[j], d2[j]);
}*/
foreach (MKeyPoint kp in keypoints)
{
box.Draw(new CircleF(kp.Point, kp.Size), new Gray(255), 1);
}
}