How Interact with ContourFinder(Contour detected -OfxOpencv),blobs VS Some kind of objects,like a simple circle or a system particle for instance?

I made a mistake. It is:

for (int i = 0, numBlobs = contourFinder.blobs.size(); i < numBlobs; ++i){

If you don't know this syntax, it is possible to inialize more than one variable in the first part of the for(). This is the same as

int numBlobs = contourFinder.blobs.size();
for (int i = 0; i < numBlobs; ++i){

except that in the first case numBlobs is local to the loop.