Question

我尝试比较相机拍摄的纸币是否与资产文件的纸币图片相同。

现在我只能比较一张钞票图像。 compare banknotes

我想像下一个视频一样实现它。

native-lib.cpp

std::vector<Mat> trainImages;

std::vector< std::vector<DMatch> > knn_matches;
std::vector<KeyPoint> keypoints1;
std::vector<KeyPoint> keypoints2;

Mat matImg;

extern "C"
JNIEXPORT void JNICALL
Java_com_example_surfwithflann2_MainActivity_sendImages(JNIEnv *env, jobject instance,
                                                       jlongArray tempAddrObj_) {

    if(trainImages.size() == 0) {
        int length = env->GetArrayLength(tempAddrObj_);
        jlong *tempAddrObj = env->GetLongArrayElements(tempAddrObj_, NULL);

        for(int i = 0; i < length; i++) {
            Mat &tempImage = *(Mat *)tempAddrObj[i];
            trainImages.push_back(tempImage);
        }
         env->ReleaseLongArrayElements(tempAddrObj_, tempAddrObj, 0);
    } else {
        __android_log_print(ANDROID_LOG_DEBUG, "TAG", "already received from java");
    }

}

static void createKeypointsAndDescriptors(const Mat& matInput) {

    int minHessian = 400;
    cv::Ptr<SURF> detector = SURF::create( minHessian ); 
    std::vector<KeyPoint> temp_keypoints;
    std::vector<std::vector<KeyPoint>> temp_keypoints1;

    Mat temp_descriptors;
    std::vector<Mat> temp_descriptors1;
    Mat descriptors2;
    std::vector< std::vector<DMatch> > temp_knn_matches;

    for(int i = 0; i < 2; i++) {
        detector->detectAndCompute( trainImages[i], noArray(), temp_keypoints, temp_descriptors );
        temp_keypoints1.push_back(temp_keypoints);
        temp_descriptors1.push_back(temp_descriptors);
    }



    detector->detectAndCompute( matInput, noArray(), keypoints2, descriptors2 );



    Ptr<DescriptorMatcher> matcher = DescriptorMatcher::create(DescriptorMatcher::FLANNBASED);

    int max = 0;

    for(int i = 0; i < 2; i++) {

        if(temp_keypoints[i].size >= 2 && keypoints2.size() >= 2)
            matcher->knnMatch( temp_descriptors1[i], descriptors2, temp_knn_matches, 2 );

        if(max < temp_knn_matches.size()) {
            max = temp_knn_matches.size();
            keypoints1 = temp_keypoints1[i];
            matImg = trainImages[i];
            knn_matches = temp_knn_matches;
        }
    }
}

extern "C"
JNIEXPORT jlong JNICALL
Java_com_example_surfwithflann2_MainActivity_surfWithFlann2(JNIEnv *env, 
jobject instance, jlong matAddrInput) {

    // TODO
    Mat &matInput = *(Mat *)matAddrInput;

    createKeypointsAndDescriptors(matInput);

    //-- Filter matches using the Lowe's ratio test
    const float ratio_thresh = 0.7f;
    std::vector<DMatch> good_matches;
    for (int i = 0; i < knn_matches.size(); i++)
    {
        if (knn_matches[i][0].distance < ratio_thresh * knn_matches[i][1].distance)
        {
            good_matches.push_back(knn_matches[i][0]);
        }
    }

   //-- Draw matches
   Mat *img_matches = new Mat();
   drawMatches( matImg, keypoints1, matInput, keypoints2, good_matches, *img_matches, Scalar::all(-1),
        Scalar::all(-1), std::vector<char>(), DrawMatchesFlags::NOT_DRAW_SINGLE_POINTS );

    matInput.release();

    return (jlong)img_matches;
}

MainActivity.java

private Mat matInput;
private Mat matResult;

public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) {
    matInput = inputFrame.rgba();
    Imgproc.cvtColor(matInput, matInput, Imgproc.COLOR_RGB2GRAY);
    long result = surfWithFlann2(matInput.getNativeObjAddr());
    matResult = new Mat(result);
    Log.d(TAG, "check");
    Imgproc.resize(matResult, matResult, matInput.size());
    return matResult;
}

两个错误交替发生。

1。 OpenCV错误：断言失败（dsize.area（）> 0 ||（inv_scale_x> 0 && inv_scale_y> 0））在无效cv :: resize（cv :: InputArray，cv :: OutputArray，cv :: Size，double，double，int），文件../../modules/imgproc/src/resize.cpp，4045行

2。结果表明，函数createKeypointsAndDescriptors（）中没有keypoints2和描述符2

在无效cv :: resize

0 个答案: