I'm trying to train SVM with my own images and feed that to the HOGDescriptor in OpenCV. I find a similar question (question). I add -rho how it do author in that question. But setSVMDetector throw Exception train image - size 28*28
code train svm
HOGDescriptor hog = new HOGDescriptor(new Size(28,28),new Size(8,8),new Size(4,4),new Size(4,4),9);
Mat trainingLabels = new Mat();
MatOfFloat temp = new MatOfFloat();
File negativeDir = new File("/home/kurenchuksergey/HogSignTrainingData/negative");
File positiveDir = new File("/home/kurenchuksergey/HogSignTrainingData/positive");
int i = -1;
float[][] hogdescriptor = new float[13992][]; //13992 - image count
for(File file:negativeDir.listFiles()){
Mat con = Imgcodecs.imread(file.getAbsolutePath(),Imgcodecs.CV_LOAD_IMAGE_GRAYSCALE);
hog.compute(con, temp);
trainingLabels.push_back(Mat.zeros(new Size(1,1),CvType.CV_32S));
}
for(File file:negativeDir.listFiles()){
Mat con = Imgcodecs.imread(file.getAbsolutePath(),Imgcodecs.CV_LOAD_IMAGE_GRAYSCALE);
hog.compute(con, temp);
hogdescriptor[++i] = temp.toArray();
trainingLabels.push_back(Mat.ones(new Size(1,1),CvType.CV_32S));
}
Mat Labels = new Mat();
trainingLabels.copyTo(Labels);
Labels.convertTo(Labels,CvType.CV_32S);
Mat mat = new Mat(hogdescriptor.length,hogdescriptor[0].length,CvType.CV_32FC1);
for(int j = 0;j<hogdescriptor.length;j++)
mat.put(i,0,hogdescriptor[i]);
TrainData trainDataHog = TrainData.create(mat,Ml.ROW_SAMPLE,Labels);
SVM svm = SVM.create();
svm.setType(SVM.C_SVC);
svm.setKernel(SVM.RBF);
svm.setDegree(0.1);
// 1.4 bug fix: old 1.4 ver gamma is 1
svm.setGamma(0.1);
svm.setCoef0(0.1);
svm.setC(1);
svm.setNu(0.1);
svm.setP(0.1);
svm.setTermCriteria(new TermCriteria(1, 20000, 0.0001));
svm.train(trainDataHog.getSamples(),Ml.ROW_SAMPLE,trainDataHog.getResponses());
svm.save("SVMHog");
And no exception, but when i try set svm to hog, i get Exception code where i'm use setSVMDetector:
SVM svm1 = SVM.load("SVMHog");
HOGDescriptor hog = new HOGDescriptor(new Size(28,28),new Size(8,8),new Size(4,4),new Size(4,4),9);
Double rho = svm1.getDecisionFunction(0,new Mat(),new Mat());
int size = (int)(svm1.getSupportVectors().total() + 1) * svm1.getSupportVectors().channels();
float[] temp = new float[size];
svm1.getSupportVectors().get(0, 0, temp);
temp[temp.length - 1] = (float)-rho;
MatOfFloat vector = new MatOfFloat(temp);
hog.setSVMDetector(vector);
And exception:
OpenCV Error: Assertion failed (checkDetectorSize()) in setSVMDetector, file /home/kurenchuksergey/opencv/modules/objdetect/src/hog.cpp, line 117
Exception in thread "main" CvException [org.opencv.core.CvException: cv::Exception: /home/kurenchuksergey/opencv/modules/objdetect/src/hog.cpp:117: error: (-215) checkDetectorSize() in function
setSVMDetector