OpenCV实战版Day01

2022.3.14

chapter1

#include <opencv2/imgcodecs.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/imgproc.hpp>
#include <iostream>
using namespace cv;
using namespace std;

/*导入图像视频和网络摄像头*/


/////////////////////////////////////// video /////////////////////////////////////
//遍历每一帧图像捕获并显示
//int main()
//{
//    string path = "Resources/test_video.mp4";
//    VideoCapture cap(path);
//    Mat img = imread(path);
//    while(true)
//    {
//        cap.read(img);
//        imshow("image", img);
//        waitKey(60);
//    }
//    return 0;
//}

/////////////////////////////////////// webcam /////////////////////////////////////
int main()
{
    //写一个相机的id号
    VideoCapture cap(0);
    Mat img;
    while (true)
    {
        cap.read(img);
        imshow("image", img);
        waitKey(1);
    }
    return 0;
}

chapter2

#include <opencv2/imgcodecs.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/imgproc.hpp>
#include <iostream>
using namespace cv;
using namespace std;


 ///////////////////           basic function           //////////////////////


int main()
{
	string path = "Resources/test.png";
	Mat img = imread(path);

	//转变灰度
	Mat imgGray, imgBlur, imgCanny,imgDil,imgErode;
	cvtColor(img,imgGray, COLOR_BGR2GRAY);
	//模糊（高斯模糊）(原图，目标图，高斯核大小，x方向标准偏差，y方向标准偏差)
	GaussianBlur(img, imgBlur,Size(3,3),3,0);
	//边缘检测（Canny边缘检测器）
	Canny(imgBlur, imgCanny, 25, 150);
	//创建轨迹栏，观察实际需要多少边缘

	//扩大和侵蚀图像（为了更好的边缘检测）
	Mat kernel = getStructuringElement(MORPH_RECT, Size(3, 3));//定义内核,只能是奇数
	dilate(imgCanny, imgDil, kernel);
	erode(imgDil, imgErode, kernel);



	imshow("image", img);
	imshow("image Gray", imgGray);
	imshow("image Blur", imgBlur);
	imshow("image Canny", imgCanny);
	imshow("image Dilation", imgDil);
	imshow("image Erode", imgErode);

	waitKey(0);
	return 0;

}

chapter3

#include <opencv2/imgcodecs.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/imgproc.hpp>
#include <iostream>
using namespace cv;
using namespace std;


///////////////////           Resize and Crop           //////////////////////


int main()
{
    string path = "Resources/test.png";
    Mat img = imread(path);

    Mat imgResize, imgResize1,imageCrop;
    //cout << img.size() << endl;//768*559

    //调整图片大小
    resize(img, imgResize, Size(640,480));//精确调整
    resize(img, imgResize1, Size(),0.5,0.5);//按比例缩放
    //裁剪
    Rect roi(100, 100,300,250);//定义矩形(起始点x,y,宽高x,y)
    imageCrop = img(roi);


    imshow("image", img);
    imshow("image Resize", imgResize);
    imshow("image Resize1", imgResize1);
    imshow("image Crop", imageCrop);
    waitKey(0);
    return 0;

}

chapter4

#include <opencv2/imgcodecs.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/imgproc.hpp>
#include <iostream>
using namespace cv;
using namespace std;


///////////////////           Draw Shapes and Text           //////////////////////


int main()
{
    //创建空白图像
    Mat img(512, 512,CV_8UC3,Scalar(255, 255, 255));

    //绘制圆形（原图，圆心，半径，颜色，厚度（可省略））
    circle(img, Point(256, 256), 155, Scalar(0, 69, 255),FILLED);//填充
    //circle(img, Point(256, 256), 50, Scalar(0, 69, 255), 10);//厚度

    //绘制矩形（对角点坐标）
    rectangle(img, Point(130, 226), Point(382, 286), Scalar(255, 255, 255),FILLED);
    //或者用chapter3中的先定义矩形再绘制，用起始点和长宽
    //Rect roi(100, 100, 300, 250);
    //rectangle(img, roi, Scalar(255, 255, 222),5);

    //画线
    line(img, Point(130, 296), Point(382,296), Scalar(255,255,255),2);

    //文本(图片，文字内容，起始坐标，字体，比例，颜色，厚度)
    putText(img, "As balance dictates", Point(137, 262), FONT_HERSHEY_PLAIN,1.48,Scalar(0,69,255),2);

    imshow("image", img);
    
    waitKey(0);
    return 0;

}

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