二维码的定位

准备安装opencv和配置好clion中的环境

版主用的相机是小觅相机，opencv环境和cmake也是匹配好的
参考添加链接描述

C++demo：图片二维码定位

#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include <iostream>using namespace cv;
using namespace std;Mat src;
Mat src_gray;RNG rng(12345);
//Scalar colorful = CV_RGB(rng.uniform(0,255),rng.uniform(0,255),rng.uniform(0,255));Point Center_cal(vector<vector<Point> > contours, int i)//找到所提取轮廓的中心点
{int centerx = 0, centery = 0, n = contours[i].size();//在提取的小正方形的边界上每隔周长个像素提取一个点的坐标，求所提取四个点的平均坐标（即为小正方形的大致中心）centerx = (contours[i][n / 4].x + contours[i][n * 2 / 4].x + contours[i][3 * n / 4].x + contours[i][n - 1].x) / 4;centery = (contours[i][n / 4].y + contours[i][n * 2 / 4].y + contours[i][3 * n / 4].y + contours[i][n - 1].y) / 4;Point point1 = Point(centerx, centery);return point1;
}int main(int argc, char const* argv[])
{
//    src = imread("/home/dzy/MYNT-EYE-D-SDK/samples/src/imgs/aaa.jpg");src = imread("/home/dzy/MYNT-EYE-D-SDK/samples/src/imgs/weixin.png");// 图片的缩小
//    Mat dstImage1;
//    Mat tempImage = src;
//    resize( tempImage, dstImage1, Size(tempImage.cols/4, tempImage.rows/4), 0, 0, INTER_NEAREST );
//    imshow("er_src", dstImage1);Mat src_all = src.clone();cvtColor(src, src_gray, CV_BGR2GRAY);blur(src_gray, src_gray, Size(3, 3));//均值滤波//    equalizeHist(src_gray, src_gray);
//    imshow("lvbo_hou", src_gray);Scalar color = Scalar(1, 1, 255);Mat threshold_output;vector<Vec4i> hierarchy;Mat drawing = Mat::zeros(src.size(), CV_8UC3);Mat drawing2 = Mat::zeros(src.size(), CV_8UC3);threshold(src_gray, threshold_output, 112, 255, THRESH_BINARY);
//    imshow("threshold_output", threshold_output);//Canny(src_gray,threshold_output,136,196,3);//imshow("预处理后：",threshold_output);//寻找轮廓//第一个参数是输入图像 2值化的//第二个参数是内存存储器，FindContours找到的轮廓放到内存里面。//第三个参数是层级，**[Next, Previous, First_Child, Parent]** 的vector//第四个参数是类型，采用树结构//第五个参数是节点拟合模式，这里是全部寻找vector<vector<Point> > contours, contours2;findContours(threshold_output, contours, hierarchy, CV_RETR_TREE, CHAIN_APPROX_NONE, Point(0, 0));//CHAIN_APPROX_NONE全体,CV_CHAIN_APPROX_SIMPLE,,,RETR_TREE    RETR_EXTERNAL    RETR_LIST   RETR_CCOMPint c = 0, ic = 0, k = 0, area = 0;//程序的核心筛选int parentIdx = -1;for (int i = 0; i < contours.size(); i++){if (hierarchy[i][2] != -1 && ic == 0){parentIdx = i;ic++;}else if (hierarchy[i][2] != -1){ic++;}else if (hierarchy[i][2] == -1){ic = 0;parentIdx = -1;}if (ic >= 2){contours2.push_back(contours[parentIdx]);drawContours(drawing, contours, parentIdx,Scalar(1, 1, 255), 1, 8);ic = 0;parentIdx = -1;area = contourArea(contours[i]);//得出一个二维码定位角的面积，以便计算其边长（area_side）（数据覆盖无所谓，三个定位角中任意一个数据都可以）}}for (int i = 0; i < contours2.size(); i++)drawContours(drawing2, contours2, i, CV_RGB(rng.uniform(100, 255), rng.uniform(100, 255), rng.uniform(100, 255)), -1, 4, hierarchy[k][2], 0, Point());Point point[3];for (int i = 0; i < contours2.size(); i++){point[i] = Center_cal(contours2, i);}if (!contours2.empty() && contours2.size()>2){vector<Point> &vector_t = contours2[1];if (!vector_t.empty() && vector_t.size()>1){area = contourArea(vector_t);//为什么这一句和前面一句计算的面积不一样呢int area_side = cvRound(sqrt(double(area)));for (int i = 0; i < contours2.size(); i++){line(drawing2, point[i%contours2.size()], point[(i + 1) % contours2.size()], color, area_side / 4, 8);}//            imshow("tiqu_hou", drawing2);
//            printf("%d\n", contours.size());
//            imshow( "Contours", drawing );//接下来要框出这整个二维码Mat gray_all, threshold_output_all;vector<vector<Point> > contours_all;vector<Vec4i> hierarchy_all;cvtColor(drawing2, gray_all, CV_BGR2GRAY);
//            imshow( "gray_all", gray_all );threshold(gray_all, threshold_output_all, 45, 255, THRESH_BINARY);
//            imshow( "threshold_output_all", threshold_output_all );//表示只寻找出来连线的最外层轮廓findContours(threshold_output_all, contours_all, hierarchy_all, RETR_EXTERNAL, CHAIN_APPROX_NONE, Point(0, 0));//RETR_EXTERNAL表示只寻找最外层轮廓//求最小包围矩形，斜的也可以哦RotatedRect rectPoint = minAreaRect(contours_all[0]);Point2f fourPoint2f[4];//将rectPoint变量中存储的坐标值放到 fourPoint的数组中rectPoint.points(fourPoint2f);for (int i = 0; i < 4; i++){line(src_all, fourPoint2f[i % 4], fourPoint2f[(i + 1) % 4], Scalar(1, 1, 255), 3);}/*** 图片截取* */int threshold_val = 20;Mat img = src;Mat dst;Mat roi = Mat::zeros(img.size(),CV_8U);vector<vector<Point>> contour;vector<Point> pts;pts.emplace_back(Point( fourPoint2f[0].x-threshold_val,fourPoint2f[0].y+threshold_val));//左下角坐标pts.emplace_back(Point( fourPoint2f[1].x-threshold_val,fourPoint2f[1].y-threshold_val));//左上角坐标pts.emplace_back(Point( fourPoint2f[2].x+threshold_val,fourPoint2f[2].y-threshold_val));//右上角坐标pts.emplace_back(Point( fourPoint2f[3].x+threshold_val,fourPoint2f[3].y+threshold_val));//右下角坐标contour.push_back(pts);drawContours(roi,contour,0,Scalar::all(255),-1);img.copyTo(dst,roi);imshow("dst",dst);imwrite("../../src/out_ers/caijian1.png",dst);imshow("erweima", src_all);}}waitKey(0);return(0);
}

使用zbar读取二维码信息

安装zbar和测试执行zbar

参考： https://blog.csdn.net/Kano365/article/details/89636188

我在编译zbar时正常通过，在执行时出现错误--------------------- zbarcam: error while loading shared libraries: libzbar.so.0: cannot open shared object file: No such file or directory
查阅了一下资料：

https://blog.csdn.net/Visrul/article/details/80406830
https://blog.csdn.net/starelegant/article/details/77869792
都没有找到合适的解决办法，最终在/usr/local/lib目录下执行终端窗口执行ldconfig命令，执行通过～ 原因可能为刚安装的zbar库动态链接并没有加载的缓存文件中需要执行ldconfig命令。

如果共享库文件安装到了/lib或/usr/lib目录下, 那么需执行一下ldconfig命令
ldconfig命令的用途, 主要是在默认搜寻目录(/lib和/usr/lib)以及动态库配置文件/etc/ld.so.conf内所列的目录下, 搜索出可共享的动态链接库(格式如lib*.so*), 进而创建出动态装入程序(ld.so)所需的连接和缓存文件. 缓存文件默认为/etc/ld.so.cache, 此文件保存已排好序的动态链接库名字列表.

C++demo：读取二维码图片上数据

#include <iostream>
#include <zbar.h>
#include <opencv2/opencv.hpp>using namespace std;
using namespace cv;int main(){zbar::ImageScanner scanner;scanner.set_config(zbar::ZBAR_NONE, zbar::ZBAR_CFG_ENABLE, 1);cv::Mat img = cv::imread("/home/dzy/MYNT-EYE-D-SDK/samples/src/imgs/weixin.png");cv::Mat imgGray;imgGray.create(img.size(), CV_8UC1);cvtColor(img, imgGray, CV_BGR2GRAY);int width = imgGray.cols;int height = imgGray.rows;zbar::Image image(width, height, "Y800", imgGray.data, width *height);int n = scanner.scan(image);for (zbar::Image::SymbolIterator symbol = image.symbol_begin();symbol != image.symbol_end();++symbol) {
//        cout << "decoded " << symbol->get_type_name()<< " symbol \"" << symbol->get_data() << '"' << endl;cout << symbol->get_data() << endl;}image.set_data(NULL, 0);return(0);
}

其他博主参考

参考链接：https://www.cnblogs.com/lx17746071609/p/11428788.html
源文件.cpp

#include <opencv2/opencv.hpp>
#include <zbar.h>using namespace cv;
using namespace std;
using namespace zbar;typedef struct
{string type;string data;vector <Point> location;
} decodedObject;// 查找和解码条形码和二维码
void decode(Mat &im, vector<decodedObject>&decodedObjects)
{// 创建ZBAR扫描器ImageScanner scanner;scanner.set_config(ZBAR_NONE, ZBAR_CFG_ENABLE, 1);// 将图像转换为灰度Mat imGray;cvtColor(im, imGray, COLOR_BGR2GRAY);imshow("gray",imGray);// 在ZBAR图像中包装图像数据Image image(im.cols, im.rows, "Y800", (uchar *)imGray.data, im.cols * im.rows);// 扫描图像中的条形码和二维码int n = scanner.scan(image);// 打印输出结果for (Image::SymbolIterator symbol = image.symbol_begin(); symbol != image.symbol_end(); ++symbol){decodedObject obj;obj.type = symbol->get_type_name();obj.data = symbol->get_data();// Print type and datacout << "Type : " << obj.type << endl;cout << "Data : " << obj.data << endl << endl;// Obtain locationfor (int i = 0; i < symbol->get_location_size(); i++){obj.location.push_back(Point(symbol->get_location_x(i), symbol->get_location_y(i)));}decodedObjects.push_back(obj);}
}// 显示条形码和二维码位置
void display(Mat &im, vector<decodedObject>&decodedObjects)
{// 循环所有解码对象for (int i = 0; i < decodedObjects.size(); i++){vector<Point> points = decodedObjects[i].location;vector<Point> hull;// 如果这些点不形成四边形，则找到凸包。if (points.size() > 4)convexHull(points, hull);elsehull = points;// 凸包中的点数int n = hull.size();for (int j = 0; j < n; j++){line(im, hull[j], hull[(j + 1) % n], Scalar(255, 0, 0), 3);}}// 显示结果imshow("Results", im);waitKey(0);}int main(int argc, char* argv[])
{// Read imageMat im = imread("/home/dzy/MYNT-EYE-D-SDK/samples/src/imgs/weixin.png");imshow("Results", im);// Variable for decoded objectsvector<decodedObject> decodedObjects;// Find and decode barcodes and QR codesdecode(im, decodedObjects);// Display locationdisplay(im, decodedObjects);waitKey(0);return 0;
}

CMakeLists.txt配置

cmake_minimum_required(VERSION 3.13)
project(ercode)set(CMAKE_CXX_STANDARD 14)add_executable(ercode main.cpp)#找到opencv的包
set(TARGET_LIBS "/usr/local/include/opencv2/")
find_package( OpenCV REQUIRED )
include_directories( ${OpenCV_INCLUDE_DIRS} )#zbar
set(zbar_include_dir "/usr/local/include")
set(zbar_link_dir "/usr/local/lib")
include_directories(${zbar_include_dir})
link_directories(${zbar_link_dir})
link_libraries(zbar)#动态链接
target_link_libraries(ercode ${OpenCV_LIBS} )
target_link_libraries(ercode jsoncpp)
target_link_libraries(ercode zbar)

编写不宜，如果帮助记得打赏