opencv 绘制图像文字、图像对比度调整（2）

1、调整图像对比度

#include<opencv2/opencv.hpp>
#include<iostream>
#include<math.h>
using namespace std;
using namespace cv;
int main()
{

Mat src = imread("C:/Users/admin/Desktop/1.JPG");
if (!src.data)
{
  printf("没找到");
  return -1;
}
Mat src1;
cvtColor(src, src1, COLOR_BGR2GRAY);
Mat dst = Mat::zeros(src.size(), src.type());
float k = 1.2, c = 80;
int width = src.cols;
int height = src.rows;
Mat m1;
src.convertTo(m1, CV_32F);//转float
for (int row = 0; row < height; row++)
{
  for (int col = 0; col < width; col++)
  {
    if (src.channels()==3)
    {
      //拿到src的每个像素点
      /*int b = src.at<Vec3b>(row, col)[0];
      int g = src.at<Vec3b>(row, col)[1];
      int r = src.at<Vec3b>(row, col)[2];*/
      float b = m1.at<Vec3f>(row, col)[0];
      float g = m1.at<Vec3f>(row, col)[1];
      float r = m1.at<Vec3f>(row, col)[2];
      dst.at<Vec3b>(row, col)[0] = saturate_cast<uchar>(k*b + c);
      dst.at<Vec3b>(row, col)[1] = saturate_cast<uchar>(k*b + c);
      dst.at<Vec3b>(row, col)[2] = saturate_cast<uchar>(k*b + c);

    }
    else if (src.channels()==1)
    {
      int r = src.at<uchar>(row, col);
      dst.at<uchar>(row, col) = saturate_cast<uchar>(k*r + c);
    }
  }
}
namedWindow("dstImg window", CV_WINDOW_AUTOSIZE);
imshow("dstImg window", dst);
namedWindow("srcImg window", CV_WINDOW_AUTOSIZE);
imshow("srcImg window", src);
waitKey(0);
return 0;

}

2、绘制形状文字

#include <iostream>
#include<opencv2/opencv.hpp>
using namespace std;
using namespace cv;


Mat bgImg;
const char* drawDome = "draw shapes and text Dome";
void myLines();
void myRectangle();
void myEllipse();
void myCircle();
void myPolygon();
void randomLine();
int main()
{
  bgImg = imread("C:/Users/admin/Desktop/1.JPG");
  if (!bgImg.data)
  {
    printf("未找到图像");
    return -1;
  }
  /*putText(bgImg, "Hello world", Point(100, 100), CV_FONT_HERSHEY_COMPLEX, 2.0, Scalar(23, 155, 11), 1, CV_AA);
  myLines();
  myCircle();
  myRectangle();
  myEllipse();
  myPolygon();*/
  randomLine();
  namedWindow(drawDome, CV_WINDOW_AUTOSIZE);
  imshow(drawDome, bgImg);
  waitKey(0);
  return 0;
}

void myLines()
{
  Point p1 = Point(20, 30);
  Point p2;
  p2.x = 300;
  p2.y = 300;
  Scalar color = Scalar(0, 0, 255);
  line(bgImg, p1, p2, color, 1, CV_AA);
}

void myRectangle()
{
  Rect rect = Rect(200, 100, 300, 300);
  rectangle(bgImg, rect, Scalar(255, 0, 0), 1, 8, 0);
}

void myEllipse()
{
  ellipse(bgImg, Point(bgImg.cols / 2, bgImg.rows / 2), Size(bgImg.cols / 4, bgImg.rows / 8), 90, 0, 360, Scalar(0, 255, 0), 1, CV_AA);
}

void myCircle()
{
  Scalar color = Scalar(0, 255, 255);
  Point center = Point(bgImg.cols / 2, bgImg.rows / 2);
  circle(bgImg, center, 100, color, 2, CV_AA);
}

//绘制多边形
void myPolygon()
{
  Point pts[1][5];
  pts[0][0] = Point(100, 100);
  pts[0][1] = Point(100, 200);
  pts[0][2] = Point(200, 200);
  pts[0][3] = Point(200, 100);
  pts[0][4] = Point(100, 100);

  const Point* ppts[] = {pts[0]};
  int npt[] = { 5 };
  Scalar color = Scalar(255, 12, 255);
  fillPoly(bgImg, ppts, npt, 1, color, CV_AA);
}

void randomLine()
{
  RNG reg(12345);//生成随机数，传入随机种子
  Point p1, p2;
  Mat randomImg = Mat::zeros(bgImg.size(), bgImg.type());

  for (int i = 0; i < 10000; i++)
  {
    p1.x = reg.uniform(0, randomImg.cols);
    p1.y = reg.uniform(0, randomImg.rows);

    p2.x = reg.uniform(0, randomImg.cols);
    p2.y = reg.uniform(0, randomImg.rows);
    line(randomImg, p1, p2, Scalar(reg.uniform(0, 255), reg.uniform(0, 255), reg.uniform(0, 255)), 1, CV_AA);
    if (waitKey(50)>0)
    {
      break;
    }
    namedWindow("randomImg window", CV_WINDOW_AUTOSIZE);
    imshow("randomImg window", randomImg);
  }
}