OpenCV FeatureDetector

Question

我正在尝试编写一个应用SURF对象检测的代码,所以我采用了一个openCV示例(示例3)并开始更新onCameraViewStarted()和onCameraFrame()方法,但是当我在我的Galaxy S3手机上尝试它时,我一直收到运行时错误找不到任何可以解决我的问题的方法是我的代码和我更新的内容:

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;
}
}

注意:我已尝试评论除了方法featureDetector.detect(mRgba, keyPoints)中的所有内容,但onCameraFrame()仍然在手机上发出运行时错误.

Answer 1

如果我没记错的话，OpenCV SURF 特征检测器仅适用于灰度图像。因此，尝试在方法中调用copyToonCameraFrame()之后添加此内容：

cvtColor(mRgba, mGrayMat, COLOR_RGBA2GRAY);