I am trying to write a code that applies SURF object detection, so I took one of the openCV samples ( sample 3 ) and I started updating the onCameraViewStarted()
and onCameraFrame()
methods but I keep getting a runtime error when I try it on my galaxy S3 phone and I couldn't find anything to help with my problem here is my code and what I updated:
public class Sample3Native extends Activity implements CvCameraViewListener{
private static final String TAG = "OCVSample::Activity";
private Mat mRgba;
private Mat mGrayMat;
private CameraBridgeViewBase mOpenCvCameraView;
Mat descriptors ;
List<Mat> descriptorsList;
FeatureDetector featureDetector;
MatOfKeyPoint keyPoints;
DescriptorExtractor descriptorExtractor;
DescriptorMatcher descriptorMatcher;**
private BaseLoaderCallback mLoaderCallback = new BaseLoaderCallback(this) {
@Override
public void onManagerConnected(int status) {
switch (status) {
case LoaderCallbackInterface.SUCCESS:
{
Log.i(TAG, "OpenCV loaded successfully");
// Load native library after(!) OpenCV initialization
System.loadLibrary("native_sample");
mOpenCvCameraView.enableView();
} break;
default:
{
super.onManagerConnected(status);
} break;
}
}
};
public void onCameraViewStarted(int width, int height) {
mRgba = new Mat(height, width, CvType.CV_8UC4);
mGrayMat = new Mat(height, width, CvType.CV_8UC1);
featureDetector=FeatureDetector.create(4); // SURF= 4;
descriptorExtractor=DescriptorExtractor.create(2);//SURF = 2
descriptorMatcher=DescriptorMatcher.create(6); //BRUTEFORCE_SL2 = 6**
}
public Mat onCameraFrame(Mat inputFrame) {
inputFrame.copyTo(mRgba);
//detect_1(0, mRgba.getNativeObjAddr(), keyPoints.getNativeObjAddr());
//Now mRgba contains the current frame ( start manipulation part)
//detecting keypoints
featureDetector.detect(mRgba, keyPoints);
//draw keypoints
// Features2d.drawKeypoints(mRgba, keyPoints, mRgba);
//finding descriptors
descriptorExtractor.compute(mRgba, keyPoints, descriptors);
//Matcher between 2 images or set of images
// Note: training set and query set are handled here! (in matcher)
//descriptorsList = descriptorMatcher.getTrainDescriptors();
//descriptorsList.add(descriptors);
// descriptorMatcher.add(descriptorsList);
//Imgproc.cvtColor(mRgba, mGrayMat, Imgproc.COLOR_RGBA2GRAY);
//FindFeatures(mGrayMat.getNativeObjAddr(), mRgba.getNativeObjAddr());
return mRgba;
}
}
Note: I have tried commenting everything but the featureDetector.detect(mRgba, keyPoints)
in the onCameraFrame()
method and still gave runtime error on my phone.
If I'm not mistaken, OpenCV SURF Feature Detector only works with grayscale images. So try to add this after your call to copyTo in the onCameraFrame()
method:
cvtColor(mRgba, mGrayMat, COLOR_RGBA2GRAY);