public float classify(Image<Bgr, Byte> predImg)
{
using (SURF detector = new SURF(30))
using (BFMatcher matcher = new BFMatcher(DistanceType.L2))
using (Image<Gray, Byte> testImgGray = predImg.Convert<Gray, Byte>())
using (VectorOfKeyPoint testKeyPoints = new VectorOfKeyPoint())
using (Mat testBOWDescriptor = new Mat())
using( bowDE = new BOWImgDescriptorExtractor(detector, matcher))
{
float result = 0;
bowDE.SetVocabulary(vocabulary);
detector.DetectRaw(predImg, testKeyPoints, null);
bowDE.Compute(predImg, testKeyPoints, testBOWDescriptor);
if(!testBOWDescriptor.IsEmpty)
result = svmClassifier.Predict(testBOWDescriptor);
//result will indicate whether test image belongs to trainDescriptor label 1, 2
return result;
}
}
public void computeAndExtract()
{
using (detector = new SURF(30))
using (matcher = new BFMatcher(DistanceType.L2))
{
bowDE = new BOWImgDescriptorExtractor(detector, matcher);
BOWKMeansTrainer bowTrainer = new BOWKMeansTrainer(100, new MCvTermCriteria(100, 0.01), 3, Emgu.CV.CvEnum.KMeansInitType.PPCenters);
foreach(FileInfo[] folder in _folders)
foreach (FileInfo file in folder)
{
using (Image<Bgr, Byte> model = new Image<Bgr, byte>(file.FullName))
using (VectorOfKeyPoint modelKeyPoints = new VectorOfKeyPoint())
//Detect SURF key points from images
{
detector.DetectRaw(model, modelKeyPoints);
//Compute detected SURF key points & extract modelDescriptors
Mat modelDescriptors = new Mat();
detector.Compute(model, modelKeyPoints, modelDescriptors);
//Add the extracted BoW modelDescriptors into BOW trainer
bowTrainer.Add(modelDescriptors);
}
input_num++;
}
//Cluster the feature vectors
bowTrainer.Cluster(vocabulary);
//Store the vocabulary
bowDE.SetVocabulary(vocabulary);
//training descriptors
tDescriptors = new Mat();
labels = new Matrix<int>(1, input_num);
int index = 0;
//compute and store BOWDescriptors and set labels
for (int i = 1; i <= _folders.Count; i++)
{
FileInfo[] files = _folders[i-1];
for (int j = 0; j < files.Length; j++)
{
FileInfo file = files[j];
using (Image<Bgr, Byte> model = new Image<Bgr, Byte>(file.FullName))
using (VectorOfKeyPoint modelKeyPoints = new VectorOfKeyPoint())
using (Mat modelBOWDescriptor = new Mat())
{
detector.DetectRaw(model, modelKeyPoints);
bowDE.Compute(model, modelKeyPoints, modelBOWDescriptor);
tDescriptors.PushBack(modelBOWDescriptor);
labels[0, index++] = i;
}
}
}
}
}