opencv与qt5GUI融合

win.h

#ifndef WIN_H
#define WIN_H

#include <QWidget>
#include <QDebug>
#include <QFileDialog>
#include<opencv2/opencv.hpp>
#include <QPushButton>
#include <QLabel>


class win : public QWidget
{
    Q_OBJECT

public:
    win(QWidget *parent = nullptr);
    ~win();

public slots:
    void on_openButton_clicked();


private:
    QString img_name;
    cv::Mat src;
    QImage img;
    QLabel* label;
    QPixmap p;



};
#endif // WIN_H

win.cpp

#include "win.h"


win::win(QWidget *parent)
    : QWidget(parent)
{
    this->resize(500,400);
    label=new QLabel(this);

    QPushButton* btn=new QPushButton("打开",this);
    btn->move(400,350);
    connect(btn,&QPushButton::clicked,this,&win::on_openButton_clicked);


}

win::~win()
{
}

void win::on_openButton_clicked()
{

img_name = QFileDialog::getOpenFileName( this, tr("请选择需要打开的图片"), ".",tr("Image Files(*.png *.jpg *.jpeg *.bmp)"));
if(img_name.length()<=0)return;
qDebug()<<img_name;  //"D:/bb/tu/a.png"
//src=cv::imread(img_name); //这是错误的，因为opencv不认识Qstring
src=cv::imread(img_name.toUtf8().data());
qDebug()<<img_name.toUtf8().data(); //  D:/bb/tu/a.png
//data()表示返回QByteArray的指针
cv::namedWindow( "src", cv::WINDOW_NORMAL );
if(!src.empty()){
       cv::imshow("src",src);}


img = QImage( (const unsigned char*)(src.data), src.cols, src.rows, QImage::Format_RGB888 );//把opencv图像转换成QImage图像
img=img.rgbSwapped();//RGB和BGR格式互换
//QImage是RGB顺序   opencv是BGR顺序
p.convertFromImage(img);  //把QImage转换成QPixmap
label->setPixmap(p);
label->resize(src.cols,src.rows);



}