void cvCalcCovarMatrix(CvArr** vects, int count, CvArr* cov_mat, CvArr* avg, int flags) {
    void *fptr;

    fptr = dlsym(_Chcv_handle, "cvCalcCovarMatrix_chdl");
    if(fptr == NULL) {
        fprintf(_stderr, "Error: %s(): dlsym(): %s\n", __func__,  dlerror());
        return;
    }
    dlrunfun(fptr, NULL, cvCalcCovarMatrix, vects, count, cov_mat, avg, flags);
}