电脑摄像头拍照

#include "qtusecamera.h"
#include<opencv/cv.h>
#include<opencv/highgui.h>
#include<windows.h>

QtUseCamera::QtUseCamera(QWidget *parent, Qt::WFlags flags)
: QWidget(parent, flags)
{
preReadLabel = new QLabel;
photoLabel =new QLabel;
openBut = new QPushButton("打开");
takeBut = new QPushButton("拍照");
closeBut=new QPushButton("关闭");
saveBut=new QPushButton("保存");
labelLayout=new QHBoxLayout;
butLayout=new QHBoxLayout;
mainLayout=new QVBoxLayout;
labelLayout->addWidget(preReadLabel);
labelLayout->addWidget(photoLabel);
butLayout->addWidget(openBut);
butLayout->addWidget(takeBut);
butLayout->addStretch();
butLayout->addWidget(saveBut);
butLayout->addWidget(closeBut);
butLayout->setContentsMargins(10,5,10,5);
mainLayout->addLayout(labelLayout);
mainLayout->addLayout(butLayout);
mainLayout->setSpacing(1);
mainLayout->setContentsMargins(0,0,0,0);
setLayout(mainLayout);

timer=new QTimer;
connect(openBut,SIGNAL(clicked()),this,SLOT(openCamera()));
connect(takeBut,SIGNAL(clicked()),this,SLOT(takingPictures()));
connect(closeBut,SIGNAL(clicked()),this,SLOT(closeCamera()));
connect(timer,SIGNAL(timeout()),this,SLOT(readFrame()));
connect(saveBut,SIGNAL(clicked()),this,SLOT(savePic()));

cam=NULL;
resize(200,200);
setWindowTitle("摄像头拍照");
}

QtUseCamera::~QtUseCamera()
{
cvReleaseCapture(&cam);
}

void QtUseCamera::openCamera(){
cam = cvCreateCameraCapture(0);
Sleep(1000);
timer->start(30);
}
void QtUseCamera::readFrame(){
if(!cam) return ;
frame = cvQueryFrame(cam);
QImage image = QImage((const uchar*)frame->imageData,
frame->width,
frame->height,
QImage::Format_RGB888).rgbSwapped();
preReadLabel->setPixmap(QPixmap::fromImage(image));
}
void QtUseCamera::closeCamera(){
timer->stop();
cvReleaseCapture(&cam);
preReadLabel->setPixmap(QPixmap());
photoLabel->setPixmap(QPixmap());
takePic=QImage();
resize(200,200);
}
void QtUseCamera::takingPictures(){
if(!cam) return ;
frame = cvQueryFrame(cam);
takePic = QImage((const uchar*)frame->imageData,
frame->width,
frame->height,
QImage::Format_RGB888).rgbSwapped();
photoLabel->setPixmap(QPixmap::fromImage(takePic));

}

void QtUseCamera::savePic(){
if(takePic.isNull()) return ;
QString fileName=QFileDialog::getSaveFileName(this,"保存照片",QString(),"png file(*.png)");
if(fileName.isEmpty()) return ;
takePic.save(fileName,"png",100);

}