《学习OpenCV》课后习题解答3

#include "cv.h"
#include "highgui.h"

int main(int argc, char** argv) {
IplImage* img = cvCreateImage(cvSize(100, 100), IPL_DEPTH_8U, 3);
cvZero(img);
for (int i = 20; i <= 40; i++) {
for (int j = 5; j <= 20; j++) {
*(cvPtr2D(img, i, j) + 1) = 255;
}
}

cvNamedWindow("rectangle", CV_WINDOW_AUTOSIZE);
cvShowImage("rectangle", img);
cvWaitKey(0);

cvReleaseImage(&img);
cvDestroyWindow("rectangle");
}