Try by OpenCV
2025/9/16大约 6 分钟
这是本人基于OpenCV所做的第一次小demo，旨在强化学习OpenCV的一些常见基本操作。
你不要问为什么作者写的这么垃圾，作者懒得配置Cmake的多文件编译了，直接这样写，虽然是一坨屎，一坨看都看不下去的屎，那你也得吃。
以下所有内容是通过
// 这里放你的代码
Point2f src[4] = {{529,142},{771,190},{405,395},{674,457}};
这个玩意包裹，旨在避免报错
#include <cstddef>
#include <iterator>
#include <opencv2/core.hpp>
#include <opencv2/core/mat.hpp>
#include <opencv2/core/types.hpp>
#include <opencv2/opencv.hpp> // OpenCV 核心头文件
#include <opencv2/imgcodecs.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/imgproc.hpp>
#include <iostream>
#include <opencv2/videoio.hpp>
#include <vector>
#include <opencv2/objdetect.hpp>
using namespace cv; // 简化 OpenCV 类/函数调用（避免重复写 cv::）
using namespace std;
void test1();
void test2();
void test3();
void test4();
void test5();
void test6();
void test8();//颜色检测 inRange() Trackbars
void getContours(Mat imgDil,Mat img); //轮廓识别，去掉面积小于1000的 并识别出来形状
void test9();//形状检测
void test9_1();//调用摄像头进行轮廓识别
void test10();//检测人脸
void findcolor();//调用摄像头找最适合的hsv
void test11();//自瞄装甲板,用了getArmour函数
void getArmour(Mat imgMask,Mat img);//bug很多，详情见函数介绍
void test12();//自制虚拟画笔 跳过了
void test13();//文档扫描仪器
void test14();
int main() {
test11();
}
//检测车牌
void test14(){
VideoCapture cap(0);
Mat img ;
CascadeClassifier plateCascade;
plateCascade.load("../Resources/haarcascade_russian_plate_number.xml");
if(plateCascade.empty()){cout <<"XML file not loaded"<<endl;}
vector<Rect> plates;
while(1){
cap.read(img);
plateCascade.detectMultiScale(img,plates,1.1,10);
for(unsigned int i = 0;i<plates.size();i++){
rectangle(img,plates[i].tl(),plates[i].br(),Scalar(255,0,255),3);
}
imshow("Image",img);
waitKey(1);
}
}
//扫描仪器
//img->imgGray->imgBlur->imgCanny>-imgDil
void test13(){
string path = "../Resources/paper.jpg";
Mat img = imread(path);
Mat imgGray,imgBlur,imgCanny,imgDil;
cvtColor(img, imgGray, COLOR_BGR2GRAY);
GaussianBlur(imgGray, imgBlur, Size(3,3),5,0);
Canny(imgBlur,imgCanny,10,50);
Mat kernel = getStructuringElement(MORPH_RECT, Size(3, 3));
dilate(imgCanny, imgDil, kernel);
vector<vector<Point>> contours;
vector<Vec4i> hierachy;
findContours(imgDil,contours,hierachy,RETR_EXTERNAL,CHAIN_APPROX_SIMPLE);
if (contours.empty()) {
cout << "未找到任何轮廓！" << endl;
return;
}
vector<Point> biggest;
int bigint = 0;
int maxarea = 0;
vector<vector<Point>> conPoly(contours.size());
for(unsigned int i = 0;i<contours.size();i++){
int area = contourArea(contours[i]);
if(area>1000){
float peri = arcLength(contours[i], true);
approxPolyDP(contours[i], conPoly[i], 0.02*peri, true);
if(area>maxarea && conPoly[i].size()==4){
biggest = conPoly[i];
maxarea=area;
bigint = i;
}
}
}
drawContours(img, conPoly, bigint, Scalar(0,255,0),6);
for(unsigned int i =0;i<biggest.size();i++){
circle(img, biggest[i], 5, Scalar(255,0,0),FILLED);
}
imshow("img",img);
waitKey(0);
}
//自制虚拟画笔，先跳过了
void test12(){
}
//自瞄装甲板，已经调的差不多了
void test11(){
VideoCapture cap(0);
Mat img,imgHSV,imgMask;
int hmin = 2,smin=0,vmin=254;
int hmax =51,smax=255,vmax=255;
namedWindow("Trackbars", 800);
createTrackbar("Hue Min", "Trackbars", &hmin, 179);
createTrackbar("Hue Max", "Trackbars", &hmax, 179);
createTrackbar("Sat Min", "Trackbars", &smin, 255);
createTrackbar("Sat Max", "Trackbars", &smax, 255);
createTrackbar("Val Min", "Trackbars", &vmin, 255);
createTrackbar("Val Max", "Trackbars", &vmax, 255);
while(1){
cap.read(img);
cvtColor(img, imgHSV, COLOR_BGR2HSV);
Scalar lower(hmin,smin,vmin);
Scalar upper(hmax,smax,vmax);
inRange(imgHSV, lower, upper, imgMask); //筛选颜色过后就是imgMask了
getArmour(imgMask, img);
imshow("Vedio",img);
imshow("imgMask",imgMask);
waitKey(1);
}
}
//自瞄装甲板
//底层搞了一个goalboundrect，主要是存储两个红色灯条
//坏处:一旦收到干扰，vector必炸
void getArmour(Mat imgMask,Mat img){
vector<vector<Point>> contours;
vector<Vec4i> hierarchy;
vector<Rect> goalboundRect;
findContours(imgMask,contours,hierarchy,RETR_EXTERNAL,CHAIN_APPROX_SIMPLE);
for(unsigned int i =0; i < contours.size();i++){
int area = contourArea(contours[i]);
//cout << area<<endl;
//储存每个轮廓的近似点conPoly
vector<vector<Point>> conPoly(contours.size());
vector<Rect> boundRect(contours.size());
if (area >20){
//计算周长 contours[i]：要计算的轮廓 true:闭合曲线
float peri = arcLength(contours[i], true);
// argvs: 轮廓，近似点，近似精度，闭合曲线
approxPolyDP(contours[i], conPoly[i], 0.02*peri, true);
//边界矩形
boundRect[i] = boundingRect(conPoly[i]);
rectangle(img,boundRect[i].tl(),boundRect[i].br(),Scalar(0,255,0),5);
goalboundRect.push_back(boundRect[i]);
}
}
if (goalboundRect.size() < 2) {
cout << "未找到2个有效装甲板，跳过计算！" << endl;
return;
}
Point mid1 = (goalboundRect[0].tl()+goalboundRect[0].br())/2;
Point mid2 = (goalboundRect[1].tl()+goalboundRect[1].br())/2;
double distance = norm(mid1 - mid2);
Point mid = (mid1+mid2)/2;
mid1.x = mid.x - distance/2;
mid1.y = mid.y - distance/2;
mid2.x = mid.x + distance/2;
mid2.y = mid.y + distance/2;
cout<<mid1<<mid<<endl;
rectangle(img,mid1,mid2,Scalar(0,255,0),5);
}
//用来调用摄像头找最适合的颜色区间
void findcolor(){
int hmin = 0,smin=0,vmin=0;
int hmax =179,smax=255,vmax=255;
VideoCapture cap(0);
Mat img;
Mat imgHSV,imgMask;
namedWindow("Trackbars", 800);
createTrackbar("Hue Min", "Trackbars", &hmin, 179);
createTrackbar("Hue Max", "Trackbars", &hmax, 179);
createTrackbar("Sat Min", "Trackbars", &smin, 255);
createTrackbar("Sat Max", "Trackbars", &smax, 255);
createTrackbar("Val Min", "Trackbars", &vmin, 255);
createTrackbar("Val Max", "Trackbars", &vmax, 255);
while(true){
cap.read(img);
cvtColor(img, imgHSV, COLOR_BGR2HSV);
Scalar lower(hmin,smin,vmin);
Scalar upper(hmax,smax,vmax);
inRange(imgHSV, lower, upper, imgMask);
imshow("img",img);
imshow("imgHSV",imgHSV);
imshow("imgMask",imgMask);
waitKey(1);
}
}
//人脸检测(直接套用库函数就几行代码)
void test10(){
VideoCapture cap(0);
Mat img ;
CascadeClassifier faceCascade;
faceCascade.load("../Resources/haarcascade_frontalface_default.xml");
if(faceCascade.empty()){cout <<"XML file not loaded"<<endl;}
vector<Rect> faces;
while(1){
cap.read(img);
faceCascade.detectMultiScale(img,faces,1.1,10);
for(unsigned int i = 0;i<faces.size();i++){
rectangle(img,faces[i].tl(),faces[i].br(),Scalar(255,0,255),3);
}
imshow("Image",img);
waitKey(1);
}
}
//第一个自主作业：VideoCapture识别轮廓
void test9_1(){
Mat imgGray,imgBlur,imgCanny,imgDil;
VideoCapture cap(0);
Mat img;
while(1){
cap.read(img);
cvtColor(img, imgGray, COLOR_BGR2GRAY);
GaussianBlur(imgGray, imgBlur, Size(3,3), 3,0);
Canny(imgBlur,imgCanny,25,75);
Mat kernel = getStructuringElement(MORPH_RECT, Size(3,3));
dilate(imgCanny, imgDil, kernel);//记好这个函数叫做膨胀
getContours(imgDil, img);
imshow("img",img);
waitKey(10);
}
}
//形状检测
void test9(){
Mat imgGray,imgBlur,imgCanny,imgDil;
string path = "../Resources/shapes.png";
Mat img = imread(path);
cvtColor(img, imgGray, COLOR_BGR2GRAY);
GaussianBlur(imgGray, imgBlur, Size(3,3), 3,0);
Canny(imgBlur,imgCanny,25,75);
Mat kernel = getStructuringElement(MORPH_RECT, Size(3,3));
dilate(imgCanny, imgDil, kernel);//记好这个函数叫做膨胀
getContours(imgDil, img);
imshow("img",img);
waitKey(0);
}
void getContours(Mat imgDil,Mat img){
vector<vector<Point>> contours;
vector<Vec4i> hierarchy;
findContours(imgDil,contours,hierarchy,RETR_EXTERNAL,CHAIN_APPROX_SIMPLE);
for(unsigned int i =0; i < contours.size();i++){
int area = contourArea(contours[i]);
cout << area<<endl;
//储存每个轮廓的近似点conPoly
vector<vector<Point>> conPoly(contours.size());
vector<Rect> boundRect(contours.size());
string objectType;
if (area >1000){
//计算周长 contours[i]：要计算的轮廓 true:闭合曲线
float peri = arcLength(contours[i], true);
// argvs: 轮廓，近似点，近似精度，闭合曲线
approxPolyDP(contours[i], conPoly[i], 0.02*peri, true);
drawContours(img, conPoly, i, Scalar(255,0,255),3);
cout<<conPoly[i].size()<<endl;
//边界矩形
boundRect[i] = boundingRect(conPoly[i]);
rectangle(img,boundRect[i].tl(),boundRect[i].br(),Scalar(0,255,0),5);
//
int objCor = (int)conPoly[i].size();
if (objCor == 3)objectType="Tri";
if (objCor == 4){
objectType="Square";
float aspRatio = (float) boundRect[i].height/(float) boundRect[i].width;
if(aspRatio>1.05||aspRatio<0.95)objectType="Rect";
cout<<aspRatio<<endl;
}
if (objCor > 4)objectType="Circle";
putText(img, objectType, {boundRect[i].x,boundRect[i].y-5}, FONT_HERSHEY_DUPLEX, 0.75, Scalar(75,0,255),2);
}
}
}
//HSV,mask颜色检测
void test8(){
int hmin = 0,smin=110,vmin=153;
int hmax =19,smax=240,vmax=255;
string path = "../Resources/lambo.png";
Mat img = imread(path);
Mat imgHSV,imgMask;
cvtColor(img, imgHSV, COLOR_BGR2HSV);
namedWindow("Trackbars", 400);
createTrackbar("Hue Min", "Trackbars", &hmin, 179);
createTrackbar("Hue Max", "Trackbars", &hmax, 179);
createTrackbar("Sat Min", "Trackbars", &smin, 255);
createTrackbar("Sat Max", "Trackbars", &smax, 255);
createTrackbar("Val Min", "Trackbars", &vmin, 255);
createTrackbar("Val Max", "Trackbars", &vmax, 255);
while(true){
Scalar lower(hmin,110,153);
Scalar upper(19,240,255);
inRange(imgHSV, lower, upper, imgMask);
imshow("img",img);
imshow("imgHSV",imgHSV);
imshow("imgMask",imgMask);
waitKey(1);
}
}
//warpPerspective
void test7(){
float w=250,h=350;
Mat matrix,imgWarp;
string path = "../Resources/cards.jpg";
Mat img = imread(path);
Point2f src[4] = {{529,142},{771,190},{405,395},{674,457}};
Point2f des[4] = {{0.0f,0.0f},{w,0.0f},{0.0f,h},{w,h}};
matrix = getPerspectiveTransform(src,des);
warpPerspective(img, imgWarp, matrix, Point(w,h));
for (int i =0;i<4;i++) {
circle(img, src[i], 8, Scalar(0,0,255),FILLED);
}
imshow("Image",img);
imshow("imgWarp",imgWarp);
waitKey(0);
}
//draw
void test6(){
Mat img(512,512,CV_8UC3,Scalar(255,255,255));
circle(img, Point(256,256), 155, Scalar(78,0,255),FILLED);
rectangle(img,Point(130,226),Point(382,286),Scalar(0,0,0),FILLED);
line(img,Point(130,260),Point(382,260),Scalar(0,0,0),2);
putText(img, "This is HZY", Point(130,240), FONT_HERSHEY_DUPLEX, 0.75, Scalar(75,0,255),2);
imshow("img",img);
waitKey(0);
}
//resize and crop
void test5(){
string path = "../Resources/test.png";
Mat img = imread(path);
Mat imgResize,imgCrop;
resize(img, imgResize, Size(0,0),0.5,0.5);
Rect roi(200,100,200,300);
imgCrop = img(roi);
imshow("imgResize",imgResize);
imshow("imgCrop",imgCrop);
waitKey(0);
}
//convert
void test4(){
string path = "../Resources/test.png";
Mat img = imread(path);
Mat imgGray,imgBlur,imgcanny,imgDil,imgErode;
cvtColor(img,imgGray,COLOR_BGR2GRAY);
GaussianBlur(img,imgBlur, Size(7,7),5,0);
Canny( imgBlur,imgcanny,50,150);
Mat kernel = getStructuringElement(MORPH_RECT, Size(3,3));
dilate(imgcanny, imgDil, kernel);
erode(imgDil, imgErode, kernel);
imshow("img",img);
imshow("imgGray",imgGray);
imshow("imgBlur",imgBlur);
imshow("imgcanny",imgcanny);
imshow("imgDila",imgDil);
imshow("imgErode",imgErode);
waitKey(0);
}
void test3(){
VideoCapture cap(0);
Mat img;
while(1){
cap.read(img);
imshow("Vedio",img);
waitKey(1);
}
}
void test2(){
string path = "../Resources/test_video.mp4";
VideoCapture cap(path);
Mat img;
while(true){
cap.read(img);
imshow("Image",img);
waitKey(1);
}
}
void test1(){
string path = "../Resources/test.png";
Mat img = imread(path);
imshow("Image",img);
waitKey(20);
}