qt+opencv实现图片编辑器

目录

实现效果

业务逻辑

借助QLabel容器，进行显示图片作为背景，然后重写QLabel类实现矩形，直线和圆形的实现。opencv板块直接实现相关图片操作。

核心代码部分

打开图片

//打开图片
void Widget::on_pushButton_clicked()
{
    QImage image;
    QString OpenFile;
    OpenFile = QFileDialog::getOpenFileName(this,
                                            "please choose an image file",
                                            "",
                                            "Image Files(*.jpg *.png *.bmp *.pgm *.pbm);;All(*.*)");
    if (OpenFile =="") {
        QMessageBox::warning(this,QString::fromLocal8Bit("错误"), QString::fromLocal8Bit("打开照片为空!"));
        return;
    }
    file_name = OpenFile;
    is_save = true;
    container_is_empty = false;
    image.load(OpenFile);
    src_img.load(OpenFile);
    current_img.load(OpenFile);
    ui->label->clear();
    QPixmap pixmap = QPixmap::fromImage(image);
    ui->label->resize(QSize(image.width(),image.height()));
    ui->label->setPixmap(QPixmap::fromImage(image));
    ui->label->setScaledContents(true);
    ui->radioButton->setChecked(1);
}

裁切

//裁切
void Widget::btn_cut_img_clicked() {

    if (container_is_empty){
        QMessageBox::warning(this,QString::fromLocal8Bit("错误"), QString::fromLocal8Bit("照片为空!"));
        return;
    }
    //本地裁剪
    QImage img = ui->label->pixmap()->toImage();
    QImage testImg = img.copy(begin_point.x(), begin_point.y(), end_point.x()-begin_point.x(),end_point.y()-begin_point.y());
    QPixmap resImage = QPixmap::fromImage(testImg);
    resImage.scaled(ui->label->size(), Qt::IgnoreAspectRatio);
    QSize size;
    size.setWidth(testImg.width());
    size.setHeight(testImg.height());

    ui->label->resize(size);
    ui->label->setGeometry(init_pos_x, init_pos_y, end_point.x()-begin_point.x(),end_point.y()-begin_point.y());
    ui->label->setPixmap(resImage);
    current_img = testImg.copy();
    ui->label->setScaledContents(true);
    ui->radioButton->setChecked(1);
    ui->pushButton_5->setEnabled(false);
    is_save = false;

}

改变亮度和对比度

//改变亮度和对比度
void Widget::change_bright_and_contact() {
    if (container_is_empty){
        QMessageBox::warning(this,QString::fromLocal8Bit("错误"), QString::fromLocal8Bit("照片为空!"));
        return;
    }
    bright = ui->spinBox->value();
    contract = ui->spinBox_2->value();
    printf("br= %d,con=%d\n",bright,contract);
    QImage image = ui->label->pixmap()->toImage();
    Mat img = QImageToMat(current_img),res;
    img.convertTo(res,-1,(double)(bright/30+1),contract);
    image = Mat2QImage(res);
    ui->label->setPixmap(QPixmap::fromImage(image));
    ui->label->setScaledContents(true);
    current_img = image.copy();         //保存当前图片
    is_save = false;
}

顺时针旋转和逆时针旋转

//顺时针旋转
void Widget::btn_right_rotation() {

    if (container_is_empty){
        QMessageBox::warning(this,QString::fromLocal8Bit("错误"), QString::fromLocal8Bit("照片为空!"));
        return;
    }
    //顺时针旋转90度
    QMatrix matrix;
    matrix.rotate(90.0);//以90度为例
    QImage image = ui->label->pixmap()->toImage();
    image = image.transformed(matrix,Qt::SmoothTransformation);
    QPixmap pixmap = QPixmap::fromImage(image);
    ui->label->setGeometry(init_pos_x,init_pos_y,image.width(),image.height());
    ui->label->setPixmap(QPixmap::fromImage(image));
    ui->label->setScaledContents(true);
    current_img = image.copy();
    is_save = false;

}

//逆时针旋转
void Widget::btn_left_rotation() {
    if (container_is_empty){
        QMessageBox::warning(this,QString::fromLocal8Bit("错误"), QString::fromLocal8Bit("照片为空!"));
        return;
    }
    //逆时针旋转90度
    QMatrix matrix;
    matrix.rotate(-90.0);//以90度为例
    QImage image = ui->label->pixmap()->toImage();
    image = image.transformed(matrix,Qt::SmoothTransformation);
    QPixmap pixmap = QPixmap::fromImage(image);
    ui->label->setGeometry(init_pos_x,init_pos_y,image.width(),image.height());
    ui->label->setPixmap(QPixmap::fromImage(image));
    ui->label->setScaledContents(true);
    current_img = image.copy();
    is_save = false;

}

重写的QLabel

//
// Created by ROG on 2022/10/13.
//

#include "MyLabel.h"
#include
#include 
#include 
#include 
#include
extern bool rectangle_value = false;
extern bool circle_value = false;
extern bool line_value = false;
extern bool is_operate_check = false;
extern QPoint begin_point={0,0},end_point={0,0};
MyLabel::MyLabel(QWidget *parent) : QLabel(parent)
{
}
//鼠标按下
void MyLabel::mousePressEvent(QMouseEvent *ev)
{
    //当鼠标左键按下  提示信息
    if( ev->button() ==  Qt::LeftButton && (rectangle_value || line_value || circle_value))
    {
        m_isMousePress = true;
        //获取点坐标
        m_beginPoint = ev->pos();
        qDebug()<<"00"<button() ==  Qt::LeftButton && is_operate_check){
        //记录初始坐标
        OldPos = ev->pos();
        Pressed = true;
    }
}


//鼠标释放
void MyLabel::mouseReleaseEvent(QMouseEvent *ev)
{
    if(ev->button()==Qt::LeftButton && (rectangle_value || line_value || circle_value))
    {
        m_endPoint = ev->pos();
        m_isMousePress = false;
        qDebug()<<"00"<button()==Qt::LeftButton && is_operate_check){
        Pressed = false;
        setCursor(Qt::ArrowCursor);
    }




}
//鼠标移动，更新矩形框
void MyLabel::mouseMoveEvent(QMouseEvent *ev)
{
    if( ev->buttons() &   Qt::LeftButton && (rectangle_value || line_value || circle_value))
    {
        m_midPoint=ev->pos();
        update();
    }else if (ev->buttons() &   Qt::LeftButton && is_operate_check){
        this->setCursor(Qt::SizeAllCursor);
        QPoint pos = ev->pos();
        int xPtInterval = pos.x() - OldPos.x();
        int yPtInterval = pos.y() - OldPos.y();

        XPtInterval += xPtInterval;
        YPtInterval += yPtInterval;

        OldPos = pos;

        this->setGeometry(XPtInterval,YPtInterval, this->width(), this->height());

        update();
    }
}


//画画
void MyLabel::paintEvent(QPaintEvent *ev)
{
    QLabel::paintEvent(ev);//先调用父类的paintEvent为了显示'背景'!!!

    QPainter m_painter(this);


    m_painter.setPen(QPen(Qt::red,2));
    m_painter.save();
    if (m_isMousePress)
    {
        if (rectangle_value) m_painter.drawRect(QRect(m_beginPoint,m_midPoint));
        else if (circle_value) m_painter.drawEllipse(QRectF(m_beginPoint,m_midPoint));
        else if (line_value) m_painter.drawLine(m_beginPoint,m_midPoint);
    }
    else if (!m_isMousePress )
    {
        if (rectangle_value) m_painter.drawRect(QRect(m_beginPoint,m_endPoint));
        else if (circle_value) m_painter.drawEllipse(QRectF(m_beginPoint,m_endPoint));
        else if (line_value) m_painter.drawLine(m_beginPoint,m_endPoint);
    }
    m_painter.restore();

}