EMD vs EMDL1: who is right?

edit savecancel

Hello all,

EMD and EMDL1 seem to provide different values for the same signatures. Can anybody explain? You can find my code below.

Thanks!

int main(int argc, char** argv)
{

    //make signature  
    Mat sig1(4, 3, CV_32FC1);
    Mat sig2(4, 3, CV_32FC1);

    sig1.at< float>(0, 0) = 0.5;
    sig1.at< float>(0, 1) = 0;
    sig1.at< float>(0, 2) = 0;

    sig1.at< float>(1, 0) = 0.5;
    sig1.at< float>(1, 1) = 1;
    sig1.at< float>(1, 2) = 1;

    sig1.at< float>(2, 0) = 0.0;
    sig1.at< float>(2, 1) = 1;
    sig1.at< float>(2, 2) = 0;

    sig1.at< float>(3, 0) = 0.0;
    sig1.at< float>(3, 1) = 0;
    sig1.at< float>(3, 2) = 1; 


    sig2.at< float>(0, 0) = .25;
    sig2.at< float>(0, 1) = 0;
    sig2.at< float>(0, 2) = 0;

    sig2.at< float>(1, 0) = .25;
    sig2.at< float>(1, 1) = 1;
    sig2.at< float>(1, 2) = 1;

    sig2.at< float>(2, 0) = .25;
    sig2.at< float>(2, 1) = 1;
    sig2.at< float>(2, 2) = 0;

    sig2.at< float>(3, 0) = .25;
    sig2.at< float>(3, 1) = 0;
    sig2.at< float>(3, 2) = 1; 

    float emd = cv::EMD(sig1, sig2, CV_DIST_L1); //emd 0 is best matching.   
    printf("similarity emd %5.5f %%\n", (1 - emd) * 100);

    emd = cv::EMDL1(sig1, sig2); //emd 0 is best matching.   
    printf("similarity emd L1 %5.5f %%\n", (1 - emd) * 100);

    waitKey(0); // Wait for a keystroke in the window
    return 0;
}