QT多線程調用攝像頭錄屏軟件開發
前言
實驗室項目需求，需要錄製攝像頭視頻畫面，海康大華自帶的攝像頭網頁錄製功能沒有選取區域錄製功能，並且錄製文件保存不夠便捷，文件太大，所以自己開發這個軟件，並且用了opencv壓縮視頻，可選用調取ffmpeg命令行來進一步壓縮錄製到的視頻。
一、調用攝像頭
實驗室常用的攝像頭有海康和大華兩種，rtsp有所區別，所以把攝像頭rtsp寫入配置文件方便調用,
在.pro文件中引入opencv庫，我用的是3.4.3版本
LIBS += \
D:\Softwares\ffmpeg4.1.3\lib\*.lib
INCLUDEPATH +=\
include\
D:/Softwares/opencv3.4.3GPU/build/include\
D:/Softwares/ffmpeg4.1.3/include
win32:CONFIG(release, debug|release):LIBS += \
D:/Softwares/opencv3.4.3/build/x64/vc14/lib/opencv_world343.lib
else:win32:CONFIG(debug, debug|release): LIBS += \
D:/Softwares/opencv3.4.3/build/x64/vc14/lib/opencv_world343d.lib
然後是調用攝像頭代碼片段
readvideo.h
public slots:
void setFlag(bool flag = false);
void openCamera();
private:
cv::VideoCapture capture;
cv::VideoWriter writer;
cv::Mat src_image;
void readvideo::openCamera()
{
QString sFilePath = QCoreApplication::applicationDirPath()+"/config.ini";
if(!QFileInfo::exists(sFilePath))
{
printf("FilePath is inexist!");
}
QSettings setting(sFilePath, QSettings::IniFormat);
setting.beginGroup("Hik");
QString iPrtsp = setting.value("rtsp").toString();
setting.endGroup();
capture.open(iPrtsp.toStdString().c_str());
if(!capture.isOpened())
{
return;
}
}
二、UI界面設計
1.Button
設計了五個button，分別對應五個功能，都是最關鍵的功能，在此不一一介紹，直接上代碼
代碼如下（示例）：
MainWindow.h
#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
#include <opencv2/core/core.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/opencv.hpp>
#include <opencv2/imgproc.hpp>
#include <QTimer>
#include <QDebug>
#include <QThread>
#include <QList>
#include"readvideo.h"
#include"mousechoose.h"
namespace Ui {
class MainWindow;
}
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();
private slots:
void receivePicture(QImage img);
void on_openCamera_clicked();
void on_startRecord_clicked();
void on_closeCamera_clicked();
void on_saveComplete_clicked();
void on_cut_clicked();
private:
Ui::MainWindow *ui;
MouseChoose *m_choose;
QThread *mainThread;
readvideo *videoThread;
QTimer fps_timer;
};
#endif // MAINWINDOW_H
MainWindow.cpp
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QMessageBox>
#include <QVBoxLayout>
#include <Qdir>
#include <QDebug>
#include "MyLabel.h"
#include <QProcess>
#include <QFileDialog>
using namespace cv;
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
m_choose = new MouseChoose(this);
m_choose->setGeometry(0,0,1920,980);
mainThread = new QThread;
videoThread = new readvideo;
videoThread->moveToThread(mainThread);
connect(&fps_timer, SIGNAL(timeout()),videoThread,SLOT(mainwindowDisplay()));
connect(videoThread,SIGNAL(sendPicture(QImage)),this,SLOT(receivePicture(QImage)));
this->setWindowTitle(QStringLiteral("攝像頭畫面錄製"));
fps_timer.setInterval(40);//每秒顯示25幀
QString save_picture = QCoreApplication::applicationDirPath();
QDir dir;
dir.cd(save_picture);
if(!dir.exists("Video"))
{
dir.mkdir("Video");
}
}
MainWindow::~MainWindow()
{
mainThread->wait();
delete videoThread;
delete mainThread;
delete m_choose;
delete ui;
}
void MainWindow::receivePicture(QImage img)
{
ui->label1->setPixmap(QPixmap::fromImage(img));
}
void MainWindow::on_openCamera_clicked()
{
mainThread->start();
fps_timer.start();
videoThread->openCamera();
}
void MainWindow::on_startRecord_clicked()
{
videoThread->setFlag(false);
videoThread->startRecord();
}
void MainWindow::on_closeCamera_clicked()
{
fps_timer.stop();
videoThread->closeCamera();
mainThread->quit();
mainThread->wait();
ui->label1->clear();
}
void MainWindow::on_saveComplete_clicked()
{
videoThread->setFlag(true);
videoThread->saveComplete();
}
void MainWindow::on_cut_clicked()
{
//選擇文件打開保存
QProcess * p = new QProcess(this);
QString program = "D:/Softwares/ffmpeg4.1.3/bin/ffmpeg.exe";
QString fileName = QFileDialog::getOpenFileName(
this,
tr("select a file."),
".",
tr("video files(*.avi *.mp4 *.wmv)"));
QStringList argu;
argu.append("-i");
argu.append(fileName.toStdString().c_str());
argu.append("-s");
argu.append("1920x1080");
argu.append("-c:v");
argu.append("libx265");
argu.append("-c:a");
argu.append("aac");
argu.append("-b:v");
argu.append("200k");
argu.append("-r");
argu.append("25");
argu.append("D:/QtProjects/SaveVideo/debug/Video/outtest.mp4");
p->start(program,argu);
p->waitForFinished();
delete p;
}
2.鼠標選擇矩形框錄製
根據QT帶的鼠標事件來截取錄製區域，如果不選擇矩形框那麼就是全屏錄製
代碼如下（示例）：
MouseChoose.h
#ifndef MOUSECHOOSE_H
#define MOUSECHOOSE_H
#include <QLabel>
#include <QPainter>
#include <opencv2/opencv.hpp>
#include <opencv2/core/core.hpp>
#include <opencv2/videoio.hpp>
#include <opencv2/highgui/highgui.hpp>
class MouseChoose : public QLabel
{
Q_OBJECT
public:
explicit MouseChoose(QWidget *parent = nullptr);
//鼠標按下
void mousePressEvent(QMouseEvent *ev);
//鼠標釋放
void mouseReleaseEvent(QMouseEvent *ev);
//鼠標移動
void mouseMoveEvent(QMouseEvent *ev);
//繪圖操作
void paintEvent(QPaintEvent *event);
static int m_x,m_y,m_width,m_height;
private:
QRect roirect;
bool m_isMousePress;
QPainter m_painter;
QPoint m_beginPoint;
QPoint m_midPoint;
QPoint m_endPoint;
};
#endif // MOUSECHOOSE_H
MouseChoose.cpp
#include "mousechoose.h"
#include <QDebug>
#include <QMouseEvent>
#include <QPainter>
#include <QRect>
#include <QLabel>
MouseChoose::MouseChoose(QWidget *parent) : QLabel(parent)
{
}
//鼠標按下
void MouseChoose::mousePressEvent(QMouseEvent *ev)
{
//當鼠標左鍵按下 提示信息
if( ev->button() == Qt::LeftButton)
{
m_isMousePress = true;
//獲取點座標
m_beginPoint = ev->pos();
qDebug()<<"00"<<m_beginPoint;
//update();
}
}
//鼠標釋放
void MouseChoose::mouseReleaseEvent(QMouseEvent *ev)
{
if(ev->button()==Qt::LeftButton)
{
m_endPoint = ev->pos();
m_isMousePress = false;
qDebug()<<"00"<<m_endPoint;
update();
}
}
//鼠標移動，更新矩形框
void MouseChoose::mouseMoveEvent(QMouseEvent *ev)
{
if( ev->buttons() & Qt::LeftButton )
{
m_midPoint=ev->pos();
update();
}
}
//靜態成員變量在類外分配內存空間
int MouseChoose::m_x = 0;
int MouseChoose::m_y = 0;
int MouseChoose::m_width = 0;
int MouseChoose::m_height = 0;
//畫矩形框
void MouseChoose::paintEvent(QPaintEvent *ev)
{
QLabel::paintEvent(ev);//先調用父類的paintEvent
QPainter m_painter(this);
m_painter.setPen(QPen(Qt::red,2));
if (m_isMousePress)
{
roirect = QRect(m_beginPoint,m_midPoint);
m_painter.drawRect(roirect);
MouseChoose::m_x = m_beginPoint.x();
MouseChoose::m_y = m_beginPoint.y();
MouseChoose::m_width = abs(m_midPoint.x() - m_beginPoint.x());
MouseChoose::m_height =abs(m_midPoint.y() - m_beginPoint.y());
}
else
{
roirect = QRect(m_beginPoint,m_endPoint);
m_painter.drawRect(roirect);
MouseChoose::m_x = m_beginPoint.x();
MouseChoose::m_y = m_beginPoint.y();
MouseChoose::m_width = abs(m_endPoint.x() - m_beginPoint.x());
MouseChoose::m_height = abs(m_endPoint.y() - m_beginPoint.y());
}
}
3.ffmpeg命令行壓縮
這部分已經放在Button下了，可以參考，具體實現可以去其他博主參考格式
現附上readvideo剩餘代碼
ReadVideo.h
#ifndef READVIDEO_H
#define READVIDEO_H
#include <QObject>
#include <QThread>
#include <opencv2/opencv.hpp>
#include <opencv2/core/core.hpp>
#include <opencv2/videoio.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <QMutex>
#include "mousechoose.h"
#include <QFileDialog>
class readvideo : public QObject
{
Q_OBJECT
public:
explicit readvideo(QObject *parent = 0);
~readvideo();
signals:
void sendPicture(const QImage &img);
public slots:
void setFlag(bool flag = false);
void openCamera();
void startRecord();
void closeCamera();
void saveComplete();
void mainwindowDisplay();
private:
MouseChoose *m_choose;
cv::VideoCapture capture;
cv::VideoWriter writer;
cv::Mat src_image;
QMutex m_Mutex;
bool stopFlag=false;
bool m_bUpdateMat;
};
#endif // READVIDEO_H
ReadVideo.cpp
#include "readvideo.h"
#include <QMessageBox>
#include <iostream>
#include <QDebug>
#include <QSettings>
#include <QFileInfo>
#include <QFileDialog>
#include <QDateTime>
#include <QCoreApplication>
#include <Windows.h>
readvideo::readvideo(QObject *parent):
QObject(parent)
{
stopFlag = false;
m_choose = new MouseChoose;
m_bUpdateMat =false;
}
readvideo::~readvideo()
{
delete m_choose;
}
void readvideo::openCamera()
{
QString sFilePath = QCoreApplication::applicationDirPath()+"/config.ini";
if(!QFileInfo::exists(sFilePath))
{
printf("FilePath is inexist!");
}
QSettings setting(sFilePath, QSettings::IniFormat);
setting.beginGroup("Hik");
QString iPrtsp = setting.value("rtsp").toString();
setting.endGroup();
capture.open(iPrtsp.toStdString().c_str());
if(!capture.isOpened())
{
return;
}
}
void readvideo::startRecord()
{
QString fileName = QFileDialog::getSaveFileName(nullptr,"保存文件",".",tr("*.mp4"));
cv::String file_path = fileName.toStdString();
int fps = capture.get(CV_CAP_PROP_FPS);
if(MouseChoose::m_height == 0)
{
writer.open(file_path,CV_FOURCC('D', 'I', 'V', 'X'), fps, cv::Size(capture.get(CV_CAP_PROP_FRAME_WIDTH),capture.get(CV_CAP_PROP_FRAME_HEIGHT)));
}
else
{
writer.open(file_path,CV_FOURCC('D', 'I', 'V', 'X'), fps, cv::Size(MouseChoose::m_width,MouseChoose::m_height));
}
while(!stopFlag)
{
//capture >> src_image;
if(m_bUpdateMat)
{
cv::Rect rect;
rect.width = MouseChoose::m_width;
rect.height = MouseChoose::m_height;
rect.x = MouseChoose::m_x;
rect.y = MouseChoose::m_y;
if(MouseChoose::m_height == 0)
{
// cv::imshow("錄製畫面",src_image);
writer.write(src_image);
m_bUpdateMat = false;
}
else
{
cv::Mat roimage = src_image(rect).clone();
// cv::imshow("錄製畫面", roimage);
writer.write(roimage);
m_bUpdateMat = false;
}
}
cv::waitKey(1);
}
writer.release();
}
void readvideo::mainwindowDisplay()
{
//40ms更新一次，如果不加m_bUpdateMat判斷，程序這需要10ms，開始錄製需要10ms，那麼3幀錄得都是同一畫面
// m_Mutex.lock();
capture >> src_image;
QImage img = QImage((const unsigned char*)src_image.data,
src_image.cols, src_image.rows, QImage::Format_RGB888).rgbSwapped(); //RGB格式轉換成BGR格式
m_bUpdateMat = true;
// m_Mutex.unlock();
emit sendPicture(img);
}
void readvideo::closeCamera()
{
if(!stopFlag) //如果還在保存視頻,則關閉cv窗口
{
cv::destroyWindow("video");
}
capture.release();
writer.release();
}
void readvideo::setFlag(bool flag)
{
stopFlag = flag;
}
void readvideo::saveComplete()
{
cv::destroyWindow("video");
}
該處使用的url網絡請求的數據。
總結
主線程和調用攝像頭線程，我用的是 QT更推薦的moveToThread——用moveToThread將繼承於QObject的類轉移到Thread裏這種方式，具體實現代碼中很清晰，這裏附上我的參考博客鏈接。
記錄自己C++代碼不斷進步的過程，一起加油，看到這的給我點個贊吧，謝謝！
VS+QT多線程實現——run和moveToThread 博主：Jack1009HF
https://blog.csdn.net/yrg1009/article/details/108546119