void cvSubstituteContour(CvContourScanner scanner, CvSeq* new_contour) {
    void *fptr;

    fptr = dlsym(_Chcv_handle, "cvSubstituteContour_chdl");
    if(fptr == NULL) {
        fprintf(_stderr, "Error: %s(): dlsym(): %s\n", __func__,  dlerror());
        return;
    }
    dlrunfun(fptr, NULL, cvSubstituteContour, scanner, new_contour);
}
