openClase6

    ofDrawCircle(ofGetWidth()/2, ofGetHeight()/2, amplitud);
    grayBg.draw(20,20);
    grayDiff.draw(20,300);


    // or, instead we can draw each blob individually from the blobs vector,
    // this is how to get access to them:
    for (int i = 0; i < contourFinder.nBlobs; i++){
        contourFinder.blobs[i].draw(20,600);

        // draw over the centroid if the blob is a hole
        ofSetColor(255);
        if(contourFinder.blobs[i].hole){
            ofDrawBitmapString("hole",
                               contourFinder.blobs[i].boundingRect.getCenter().x + 20,
                               contourFinder.blobs[i].boundingRect.getCenter().y + 600);
        }
    }

    // finally, a report:
    ofSetHexColor(0xffffff);
    stringstream reportStr;
    reportStr << "bg subtraction and blob detection" << endl
    << "press ' ' to capture bg" << endl
    << "threshold " << threshold << " (press: +/-)" << endl
    << "num blobs found " << contourFinder.nBlobs << ", fps: " << ofGetFrameRate();
    ofDrawBitmapString(reportStr.str(), 20, 600);
}