QT用QImage实现图片的放大缩小

void ImageWidget::Zoomin()

{

cout<<"image size: "<<ptr_image_->width()<<' '<<ptr_image_->height()<<endl;

int width = ptr_image_->width();

int height = ptr_image_->height();

*ptr_image_=ptr_image_->scaled(width*1.2,height*1.2,Qt::KeepAspectRatio);

update();

}

void ImageWidget::Zoomout()

{

int width = ptr_image_->width();

int height = ptr_image_->height();

*ptr_image_=ptr_image_->scaled(width*0.8,height*0.8,Qt::KeepAspectRatio);

update();

}