#include "myqueue.cpp"

double getDistance2(CvPoint p1, CvPoint p2) {
	return (p1.x - p2.x)*(p1.x - p2.x) + (p1.y - p2.y)*(p1.y - p2.y);
}

void findConnectedRegion(IplImage *src, IplImage *dst, CvPoint begin, int &area, double &distance2) {
	area = 0;
	distance2 = -1;
	CvPoint tmp;
	CvPoint center = cvPoint(src->width / 2, src->height / 2);
	MyQueue *q = new MyQueue();
	q->push(begin);
	while (!q->empty()) {
		tmp = q->pop();
		if (tmp.x >= 0 && tmp.y >= 0 && tmp.x < src->width && tmp.y < src->height && cvGetReal2D(src, tmp.x, tmp.y) != 0) {
			cvSetReal2D(src, tmp.x, tmp.y, 0);
			cvSetReal2D(dst, tmp.x, tmp.y, 255);
			area++;
			if (getDistance2(tmp, center) < distance2 || distance2 < 0) {
				distance2 = getDistance2(tmp, center);
			}
			q->push(cvPoint(tmp.x - 1, tmp.y));
			q->push(cvPoint(tmp.x, tmp.y - 1));
			q->push(cvPoint(tmp.x + 1, tmp.y));
			q->push(cvPoint(tmp.x, tmp.y + 1));
		}
	}
	delete q;
}

void main() {
	IplImage *frame = cvLoadImage("c:/Users/Username/Desktop/img.png", 0);
	IplImage *image = cvCloneImage(frame);
	int area;
	double distance2;
	cvNamedWindow("window");
	for (int i = 0; i < frame->height; i++) {
		for (int j = 0; j < frame->width; j++) {
			cvSetZero(image);
			findConnectedRegion(frame, image, cvPoint(i, j), area, distance2);
			if (area != 0) {
				cvShowImage("window", image);
				cvWaitKey();
			}
		}
	}
	cvDestroyAllWindows();
}