OpenCV学习08

在图片上绘画矩形框

//
//  main.cpp
//  Study08
//
//  Created by Sean on 16/2/23.
//  Copyright © 2016年 Sean. All rights reserved.
//

#include <iostream>
#include "highgui.h"

using namespace std;

int main(int argc, const char * argv[]) {
    // insert code here...
    cout << "Project Start..."<<endl;
//    int num(1) <-> int num = 1;
    IplImage* in = cvLoadImage("/Users/sean/Pictures/11.png");
    cvNamedWindow("Example08");
    CvSize size = cvGetSize(in);
    cvRectangle
    (
     in,
/*size.width是int型的，0.25是double型的，
(size.width*0.25)是double型，(int)(size.width*0.25)是int型，
但由于函数cvPoint( int x, int y )，即使输入double型的x、y也会强行被转换成int型
 */
     cvPoint
     (
      (int)(size.width*0.25),
      (int)(size.height*0.25)
      ),
     cvPoint
     (
      (int)(size.width*0.75),
      (int)(size.height*0.75)
      ),
     CvScalar(255,255,255)
     );
    cvRectangleR(in, cvRect(size.width/2, size.height/2, 100, 100), CvScalar(0,0,0));
    cvShowImage("Example08", in);
    cvWaitKey(0);
    cvReleaseImage(&in);
    cvDestroyAllWindows();
    return 0;
}