2020.6.12_p38_OpenCV使用Rect类获取矩阵中某一特定的矩形区域

2020.6.12_p38_使用Rect类获取矩阵中某一特定的矩形区域

//2020.6.12_p38_使用Rect类获取矩阵中某一特定的矩形区域
#include <opencv2/core.hpp>
using namespace cv;
#include <iostream>
using namespace std;

int main(int argc, char *argv[])
{
	Mat matrix = (Mat_<int>(5, 5) << 
		1,  2,  3,  4,  5, 
		6,  7,  8,  9,  10, 
		11, 12, 13, 14, 15, 
		16, 17, 18, 19, 20, 
		21, 22, 23, 24, 25);

	
	Mat roi1 = matrix(Rect(Point(2, 1), Point(4, 3)));//Point(2, 1)左上角坐标，Point(4, 3)不是右下角坐标.Point(4,3)-Point(2,1)得到宽：4-2=2，高：3-1=2
	Mat roi2 = matrix(Rect(2,1,2,2));//起点坐标2,1;宽2，高2
	Mat roi3 = matrix(Rect(Point(2,1),Size(2,2)));//左上角坐标，+尺寸

	Mat roi5 = matrix(Rect(2, 1, 2, 2)).clone();//克隆，复制原始位置数据

	for (int r = 0; r < roi3.rows; r++)
	{
		const int *ptr = roi3.ptr<int>(r);
		for (int c = 0; c < roi3.cols; c++)
		{
			cout << ptr[c] << ",";
		}
		cout << endl;
	}
	cout << "roi1--1:" << endl;
	for (int r = 0; r < roi1.rows; r++)
	{
		const int *ptr = roi1.ptr<int>(r);
		for (int c = 0; c < roi1.cols; c++)
		{
			cout << ptr[c] << ",";
		}
		cout << endl;
	}
	cout << "使用at访问元素:" << endl;
	for (int r = 0; r < roi1.rows; r++)
	{
		for (int c = 0; c < roi1.cols; c++)
		{
			cout << roi1.at<int>(r, c) << ",";
		}
		cout << endl;
	}

	
}