opencv 获取像素点

CvScalar pixel[2];
pixel[0] = cvGet2D(p1, 100, 100);
pixel[1] = cvGet2D(p2, 100, 100);
int nb1 = pixel[0].val[0];
int ng1 = pixel[0].val[1];
int nr1 = pixel[0].val[2];
int nb2 = pixel[1].val[0];
int ng2 = pixel[1].val[1];
int nr2 = pixel[1].val[2];