openCV Tip, Calculate overlap percent between two rectangle.

overlapPercent.cpp

http://study.marearts.com/2017/09/opencv-tip-calculate-overlap-percent.html
Mat canvas(100, 100, CV_8UC3);
canvas.setTo(0);

Rect rectA(10, 5, 50, 60);
Rect rectB(40,40,30, 40);
Rect andRect_overlap = (rectA & rectB);
Rect orRect_whole = (rectA | rectB);

cout << "rect A info. : " << rectA <<  endl;
cout << "rect B info. : " << rectB << endl << endl;
cout << "A and B region info. : " << andRect_overlap << endl;
cout << "A or B region info. : " << orRect_whole << endl << endl;

//if overlapped
if (orRect_whole.width != 0 && orRect_whole.height != 0)
{
	double overlap_percentOfA = float(andRect_overlap.area()) / rectA.area() * 100;
	double overlap_percentOfB = float(andRect_overlap.area()) / rectB.area() * 100;

	cout << "overlap percent in A " << overlap_percentOfA << "%" << endl;
	cout << "overlap percent in B " << overlap_percentOfB << "%" << endl;
}

rectangle(canvas, rectA, CV_RGB(255, 0, 0));
rectangle(canvas, rectB, CV_RGB(0, 0, 255));
rectangle(canvas, andRect_overlap, CV_RGB(0, 255, 0),1);
//rectangle(canvas, orRect_whole, CV_RGB(0, 255, 255));

imshow("canvas", canvas);
waitKey(0);