OpenCV?QT?????

??

OpenCV?????????GUI?????????????????????????????GUI????????????????Qt?????OpenCV????????

????

?QtCreator???????QMainWindow?????????????QImageShowWidget?????????????QMainWindow?centralwidget??

????

#ifndef QIMAGESHOWWIDGET_H
#define QIMAGESHOWWIDGET_H
#include 
   
    
#include 
    
     
class QImageShowWidget : public QWidget
{
    Q_OBJECT
public:
    explicit QImageShowWidget(QWidget *parent = nullptr);
    ~QImageShowWidget();
    bool LoadImage(const char *imagePath);
protected:
    void paintEvent(QPaintEvent *event);
    void Release();
    
private:
    uchar *winBuf;
    int winWidth;
    int winHeight;
    int winBandNum;
};
#endif // QIMAGESHOWWIDGET_H

source??

#include "qimageshowwidget.h"
#include 
   
    
#include 
    
     
#include 
     
      
#include 
      
       
using namespace cv;
using namespace std;
QImageShowWidget::QImageShowWidget(QWidget *parent) : QWidget(parent)
{
    setAutoFillBackground(true);
    setBackgroundRole(QPalette::Base);
    winBuf = nullptr;
    winWidth = rect().width();
    winHeight = rect().height();
    winBandNum = 3;
}
QImageShowWidget::~QImageShowWidget()
{
    if (winBuf)
    {
        delete[] winBuf;
        winBuf = nullptr;
    }
}
bool QImageShowWidget::LoadImage(const char *imagePath)
{
    Mat img = imread(imagePath);
    if (img.empty())
    {
        fprintf(stderr, "Can not load image %s\n", imagePath);
        return false;
    }
    
    Release();
    winWidth = rect().width();
    winHeight = rect().height();
    size_t winBufNum = (size_t)winWidth * winHeight * winBandNum;
    winBuf = new uchar[winBufNum];
    memset(winBuf, 255, winBufNum * sizeof(uchar));
    
    for (int ri = 0; ri < img.rows; ++ri)
    {
        for (int ci = 0; ci < img.cols; ++ci)
        {
            for (int bi = 0; bi < winBandNum; ++bi)
            {
                size_t m = (size_t)winWidth * winBandNum * ri + winBandNum * ci + bi;
                size_t n = (size_t)img.cols * winBandNum * ri + winBandNum * ci + bi;
                winBuf[m] = img.data[n];
            }
        }
    }
    
    update();
    return true;
}
void QImageShowWidget::paintEvent(QPaintEvent *event)
{
    if (!winBuf)
    {
        return;
    }
    
    QImage::Format imgFormat = QImage::Format_RGB888;
    QPainter painter(this);
    QImage qImg(winBuf, winWidth, winHeight, winWidth * winBandNum, imgFormat);
    painter.drawPixmap(0, 0, QPixmap::fromImage(qImg));
}
void QImageShowWidget::Release()
{
    if (winBuf)
    {
        delete[] winBuf;
        winBuf = nullptr;
    }
}