QImage 图片分割、保存

简介

之前一直只用Qt做图片显示，这次突发奇想想用Qt做做图像相关的，就尝试了一下图片切割，保存。

QImage介绍

QImage类为Qt提供的一个支持图像算法处理的类库，可以精确到像素及单位。在我理解不是提供了什么算法，而是为图像计算提供了基础。

构造函数

QImage()
QImage(const QSize &size, QImage::Format format)
QImage(int width, int height, QImage::Format format)
QImage(uchar *data, int width, int height, QImage::Format format, QImageCleanupFunction cleanupFunction = nullptr, void *cleanupInfo = nullptr)
QImage(const uchar *data, int width, int height, QImage::Format format, QImageCleanupFunction cleanupFunction = nullptr, void *cleanupInfo = nullptr)
QImage(uchar *data, int width, int height, int bytesPerLine, QImage::Format format, QImageCleanupFunction cleanupFunction = nullptr, void *cleanupInfo = nullptr)
QImage(const uchar *data, int width, int height, int bytesPerLine, QImage::Format format, QImageCleanupFunction cleanupFunction = nullptr, void *cleanupInfo = nullptr)
QImage(const char *const [] xpm)
QImage(const QString &fileName, const char *format = nullptr)
QImage(const QImage &image)
QImage(QImage &&other)

提供了以上构造方法，支持 uchar* ,const uchar*，filename 等元素的构造。

Format

Format	Description	Qt’s support
BMP	Windows Bitmap	Read/write
GIF	Graphic Interchange Format (optional)	Read
JPG	Joint Photographic Experts Group	Read/write
JPEG	Joint Photographic Experts Group	Read/write
PNG	Portable Network Graphics	Read/write
PBM	Portable Bitmap	Read
PGM	Portable Graymap	Read
PPM	Portable Pixmap	Read/write
XBM	X11 Bitmap	Read/write
XPM	X11 Pixmap	Read/write

QImage 支持的图片格式如上表所示，部分支持读写特性。

思路介绍

图像切割思路如下：

1.载入图片
2.切割图片
->2.1 设置切割属性：将图片切割为 n*m 个图片
->2.2 计算每个图片的rect，保存为rect列表
->2.3 利用copy(Rect)函数将指定区域图片copy出来，存储到切割列表中
3.显示图片
-> 按照rect列表显示切割后的图片
4.保存图片
-> 将切割后的图片存储到指定位置

程序部分

类图

主要由三个类组成：Image类，负责图像操作部分。MainWindow,主线调度类，负责功能性调度，或者说逻辑模块，业务部分。splite类。图片剪切设置框

在这里插入图片描述

Image类

image.cpp
image.h
image.ui

class image : public QWidget
{Q_OBJECTpublic:explicit image(QWidget *parent = nullptr);~image();//图片载入void imageLoad(const QString path);void imageLoad(const QString path, int &_width, int &_height);uchar* imageData();//图像切割void iamgeItems(int x, int y, QList<QImage> &imageList);void iamgeItems(int x, int y, QList<uchar*> &list);//uchar* 方便像素级的图像算法或者其他图像操作void iamgeItems(int x, int y, QVector<uchar*> & vector);//图像保存void imageSave();void imageSave(int index);void imageSave(int start,int end);//图像显示void imageShow();void imageShow(QList<QImage> &listImage);void imageShow(QList<uchar*> &listItems);void imageShow(QVector<uchar*> &VectorItems);static image* instance();
private:Ui::image *ui;QImage r_image;uchar * r_image_data;QList<QRect> _imageRects;QList<QImage> _imageList;QList<uchar*> _listItems;QVector<uchar*> _vectorItems;
};

图像载入

//利用load方法载入图像
void image::imageLoad(const QString path)
{r_image.load(path);
}void image::imageLoad(const QString path, int &_width, int &_height)
{r_image.load(path);_width = r_image.width();_height = r_image.height();
}

图像切割

void image::iamgeItems(int x, int y, QList<QImage> &imageList)
{int r_width = r_image.width();int r_height =  r_image.height();int cellWidth = r_width / x;int cellHeight = r_height / y;qDebug() << r_width << " " <<  r_height << " " << cellWidth << " " << cellHeight;for(int i = 0 ;i < x; i++ ){for (int j = 0; j < y; j++) {QRect rect(i * cellWidth,j * cellHeight, cellWidth,cellHeight);qDebug() << rect.x() << " " <<  rect.y() << " " << rect.width() << " " << rect.height();_imageRects.push_back(rect);imageList.push_back(r_image.copy(rect));}}_imageList = imageList;
}

图像保存

void image::imageSave()
{int i = 0;for(auto it : _imageList){QString imageName = QString("image/%1.jpg").arg(i);it.save(imageName);i++;}qDebug() << "iamge save ok";
}void image::imageSave(int index)
{_imageList.at(index).save(QString("image/%1.jpg").arg(index));
}

图像显示

void image::imageShow()
{for(int i = 0 ;i < _imageList.size() ; i++){QLabel * label = new QLabel(this);label->setGeometry(_imageRects.at(i));QPixmap pixmap(QPixmap::fromImage(_imageList.at(i)));label->setPixmap(pixmap);label->show();}
}

MainWindow

负责全部的业务逻辑部分，也就是通俗所说的调度。

mainwindow.cpp
mainwindow.h
mainwindow.ui

class MainWindow : public QMainWindow
{Q_OBJECTpublic:explicit MainWindow(QWidget *parent = nullptr);~MainWindow();void menuInit();
private:Ui::MainWindow *ui;void sltImportImage();void sltSpliteImage();void sltSaveImage();void sltcalcImage();
};

菜单初始化

void MainWindow::menuInit()
{QAction* importImage = ui->menuBar->addAction(QString("导入图片"));QAction* spliteImage = ui->menuBar->addAction(QString("切割图片"));QAction* saveImage = ui->menuBar->addAction(QString("保存图片"));QAction* calcImage = ui->menuBar->addAction(QString("算法"));connect(importImage,&QAction::triggered,this,&MainWindow::sltImportImage);connect(spliteImage,&QAction::triggered,this,&MainWindow::sltSpliteImage);connect(saveImage,&QAction::triggered,this,&MainWindow::sltSaveImage);connect(calcImage,&QAction::triggered,this,&MainWindow::sltcalcImage);
}

导入图片

void MainWindow::sltImportImage()
{QString imagePath = QFileDialog::getOpenFileName(this,"导入图片","./","*png *jpg");int imageWidth = 0,imageHeight = 0;ui->iamge->imageLoad(imagePath,imageWidth,imageHeight);ui->iamge->imageData();this->resize(imageWidth,imageHeight);
}

图片切割

void MainWindow::sltSpliteImage()
{splite *_splite = new splite();_splite->show();connect(_splite,&splite::sign_spliteinfo,[=](int x,int y){QList<QImage> imageItems;ui->iamge->iamgeItems(x,y,imageItems);ui->iamge->imageShow();});
}

图像保存

void MainWindow::sltSaveImage()
{ui->iamge->imageSave();
}

图像算法选择

void MainWindow::sltcalcImage()
{//设计中选择图像算法，注册对应图像算法，选择实现对应的图像算法//算法模块中，特意提供了将图像数据列表，方便算法操作。//近期会找一两个比较简单的图像算法来实现
}

其他函数说明

主函数

int main(int argc, char *argv[])
{QApplication a(argc, argv);MainWindow w;w.show();return a.exec();
}

splite构造函数

splite::splite(QWidget *parent) :QWidget(parent),ui(new Ui::splite)
{ui->setupUi(this);connect(ui->pushButton_right,&QPushButton::clicked,[=](){emit sign_spliteinfo(ui->lineEdit_x->text().toInt(),ui->lineEdit_y->text().toInt());this->close();});connect(ui->pushButton_cancel,&QPushButton::clicked,[=](){this->close();});
}