这里Vex3f 也可以是Vec3b
#include<opencv2\opencv.hpp>
#include<iostream>
#include<math.h>
using namespace cv;
using namespace std;
//读写图像,
//读写像素,
//修改像素值
int main()
{
Mat src = imread("E:\\vs2015\\opencvstudy\\2.jpg", 1);
if (!src.data)
{
cout << "could not load image!" << endl;
return -1;
}
//imshow("inputImage", src);
//单通道取反
Mat gray_src;
cvtColor(src, gray_src, CV_BGR2GRAY);
//imshow("gray_src", gray_src);
int rows = gray_src.rows;
int cols = gray_src.cols;
Mat gray_src_invert = Mat::zeros(gray_src.size(), gray_src.type());
/*for (int row = 0; row < rows; row++)
{
for (int col = 0; col < cols; col++)
{
int gray_pixel = gray_src.at<uchar>(row, col);
gray_src_invert.at<uchar>(row, col) = 255 - gray_pixel;
}
}
imshow("gray_src_invert", gray_src_invert);*/
//3通道取反
Mat dst,dst2;
dst.create(src.size(), src.type());
dst2.create(src.size(), src.type());
int height = src.rows;
int width = src.cols;
int nc = src.channels();
for (int row = 0; row < height; row++)
{
for (int col = 0; col < width; col++)
{
if (nc == 1)
{
int gray_pixel = gray_src.at<uchar>(row, col);
gray_src_invert.at<uchar>(row, col) = 255 - gray_pixel;
}
else if (nc == 3)
{
int b = src.at<Vec3b>(row, col)[0];
int g = src.at<Vec3b>(row, col)[1];
int r = src.at<Vec3b>(row, col)[2];
dst.at<Vec3b>(row, col)[0] = 255 - b;
dst.at<Vec3b>(row, col)[1] = 255 - g;
dst.at<Vec3b>(row, col)[2] = 255 - r;
dst2.at<Vec3b>(row, col) = (r, max(g, b));
}
}
}
//imshow("3通道取反像素操作", dst);
Mat bitwise_not_dst;
bitwise_not(src, bitwise_not_dst); //位操作取反。等价于上面的像素操作
//imshow("3通道取反bitwise_not", bitwise_not_dst);
imshow("dst2", dst2);
//空白图像赋值
Mat M3;
M3.create(gray_src.size(), gray_src.type());
M3 = Scalar(0);
imshow("空白图像", M3);
//ROI选择
Rect r(300, 300, 1000, 400); //左上角的横坐标,纵坐标,矩形高度,宽度
cout << "gray_image height:" << gray_src.rows << endl;
cout << "gray_image width:" << gray_src.cols << endl;
Mat smallImg = gray_src(r);
imshow("ROI截取图像", smallImg);
waitKey(0);
return 0;
}