1. Introduction to the environment
Windows version: Win10 X64
OpenCV version: 2.4.13.6
QT version: 5.12
2. Download the OpenCV library
OpenCV official website download address: https://opencv.org
Currently, the latest version of OpenCV on the official website is 4.2.0. The Windows version of OpenCV does not have X86 libraries after version 3.X, but only X64 libraries. If you need X86 libraries, you need to download the source code and recompile it yourself.
Since my QT software did not have a 64-bit compiler installed during installation, and I did not want to reinstall the 64-bit compiler, I chose the 2.X version to complete development and testing. The 3.X version is very convenient when adding libraries. Just one library.
After downloading the library, double-click to run it and extract it to the specified directory.
Next, you need to add the OpenCV dynamic library directory to the system environment variables, otherwise the program will crash if it cannot find the dependent library when running.
3. Description of program ideas
Program function: Open the camera in the sub-thread, obtain the camera data, pass the camera data to the main UI interface for real-time display through signals and slots, and use a timer to take the data on the label every 100ms for face detection processing , and then display the processed data on another label. The face detection classifier uses the classifier that comes with OpenCV. The main purpose of the program is to introduce how to develop OpenCV with QT.
OpenCV's own face detection classifier path: C:/OpenCV_2.4/opencv/sources/data/haarcascades_GPU/haarcascade_frontalface_alt2.xml
4. Realize the effect
5. Core code
xxx.pro project file code:
QT += core gui
QT += multimediawidgets
QT += xml
QT += multimedia
QT += network
QT += widgets
QT += serialport
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
CONFIG += c++11
# The following define makes your compiler emit warnings if you use
# any Qt feature that has been marked deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS
# You can also make your code fail to compile if it uses deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000 # disables all the APIs deprecated before Qt 6.0.0
SOURCES += \
main.cpp \
widget.cpp
HEADERS += \
widget.h
FORMS += \
widget.ui
# Default rules for deployment.
qnx: target.path = /tmp/$${TARGET}/bin
else: unix:!android: target.path = /opt/$${TARGET}/bin
!isEmpty(target.path): INSTALLS += target
#linu平台的路径设置
linux {
message('运行linu版本')
#添加opencv头文件的路径，需要根据自己的头文件路径进行修改
INCLUDEPATH+=/home/wbyq/work_pc/opencv-3.4.9/_install/install/include\
/home/wbyq/work_pc/opencv-3.4.9/_install/install/include/opencv\
/home/wbyq/work_pc/opencv-3.4.9/_install/install/include/opencv2
LIBS+=/home/wbyq/work_pc/opencv-3.4.9/_install/install/lib/libopencv_*
}
win32
{
message('运行win32版本')
#添加opencv头文件的路径，需要根据自己的头文件路径进行修改
INCLUDEPATH+=C:/OpenCV_2.4/opencv/build/include \
C:/OpenCV_2.4/opencv/build/include/opencv \
C:/OpenCV_2.4/opencv/build/include/opencv2
LIBS+=C:/OpenCV_2.4/opencv/build/x86/vc14/lib/opencv_*
}
RESOURCES += \
image.qrcwidget.cpp file code:
#include "widget.h"
#include "ui_widget.h"
class VideoAudioEncode videoaudioencode_0;
Widget::Widget(QWidget *parent)
: QWidget(parent)
, ui(new Ui::Widget)
{
ui->setupUi(this);
//驾驶室摄像头
//工作对象
videoRead_WorkClass_0=new VideoReadThread_0;
videoRead_Workthread_0=new QThread;
//连接摄像头采集信号,在主线程实时显示视频画面
connect(videoRead_WorkClass_0,SIGNAL(VideoDataOutput(QImage )),this,SLOT(VideoDataDisplay_0(QImage )));
//摄像头初始化函数
connect(this,SIGNAL(Init_VideoAudio_WorkClass_0()),videoRead_WorkClass_0,SLOT(run()));
//停止视频采集
connect(this,SIGNAL(Stop_AudioVideo0_work_0()),videoRead_WorkClass_0,SLOT(stop()));
//将工作对象移动到子线程里工作
videoRead_WorkClass_0->moveToThread(videoRead_Workthread_0);
//更新设备列表
UpdateVideoAudiodDevice(ui->comboBox_video_0,ui->plainTextEdit_log_0);
//
timer.start(100);
connect(&timer,SIGNAL(timeout()), this, SLOT(update()));
timer.start(100);
}
Widget::~Widget()
{
delete ui;
}
//分类器的路径
#define source_xml_addr "C:/OpenCV_2.4/opencv/sources/data/haarcascades_GPU/haarcascade_frontalface_alt2.xml"
//将要检测的图片路径
#define source_pix_addr "D:/linux-share-dir/1.jpg"
//人脸检测代码
void Widget::opencv_face(QImage qImage)
{
QTime time;
time.start();
static CvMemStorage* storage = 0;
static CvHaarClassifierCascade* cascade = 0;
const char*cascade_name =source_xml_addr;
//加载分类器
cascade = (CvHaarClassifierCascade*)cvLoad( cascade_name, 0, 0, 0 );
if( !cascade )
{
Log_Display_0("分类器加载错误.\n");
return ;
}
//创建内存空间
storage = cvCreateMemStorage(0);
//加载需要检测的图片
//const char* filename =source_pix_addr;
//IplImage* img = cvLoadImage(filename, 1 );
IplImage* img = QImageToIplImage(&qImage);
if(img ==nullptr )
{
Log_Display_0("图片加载错误.\n");
return;
}
double scale=1.2;
static CvScalar colors[] = {
{
{0,0,255}},{
{0,128,255}},{
{0,255,255}},{
{0,255,0}},
{
{255,128,0}},{
{255,255,0}},{
{255,0,0}},{
{255,0,255}}
};//Just some pretty colors to draw with
IplImage* gray = cvCreateImage(cvSize(img->width,img->height),8,1);
IplImage* small_img=cvCreateImage(cvSize(cvRound(img->width/scale),cvRound(img->height/scale)),8,1);
cvCvtColor(img,gray, CV_BGR2GRAY);
cvResize(gray, small_img, CV_INTER_LINEAR);
cvEqualizeHist(small_img,small_img); //直方图均衡
cvClearMemStorage(storage);
double t = (double)cvGetTickCount();
CvSeq* objects = cvHaarDetectObjects(small_img,
cascade,
storage,
1.1,
2,
0/*CV_HAAR_DO_CANNY_PRUNING*/,
cvSize(30,30));
t = (double)cvGetTickCount() - t;
//遍历找到对象和周围画盒
for(int i=0;i<(objects->total);++i)
{
CvRect* r=(CvRect*)cvGetSeqElem(objects,i);
cvRectangle(img, cvPoint(r->x*scale,r->y*scale), cvPoint((r->x+r->width)*scale,(r->y+r->height)*scale), colors[i%8]);
}
for( int i = 0; i < (objects? objects->total : 0); i++ )
{
CvRect* r = (CvRect*)cvGetSeqElem( objects, i );
CvPoint center;
int radius;
center.x = cvRound((r->x + r->width*0.5)*scale);
center.y = cvRound((r->y + r->height*0.5)*scale);
radius = cvRound((r->width + r->height)*0.25*scale);
cvCircle(img, center, radius, colors[i%8], 3, 8, 0 );
}
show_face(img); //显示检测的结果
cvReleaseImage(&gray);
cvReleaseImage(&small_img);
//释放图片
cvReleaseImage(&img);
Log_Display_0(tr("耗时:%1 ms\n").arg(time.elapsed()));
}
/*将QImage图片转为opecv的qimage格式*/
IplImage *Widget::QImageToIplImage(const QImage * qImage)
{
int width = qImage->width();
int height = qImage->height();
CvSize Size;
Size.height = height;
Size.width = width;
IplImage *IplImageBuffer = cvCreateImage(Size, IPL_DEPTH_8U, 3);
for (int y = 0; y < height; ++y)
{
for (int x = 0; x < width; ++x)
{
QRgb rgb = qImage->pixel(x, y);
CV_IMAGE_ELEM( IplImageBuffer, uchar, y, x*3+0 ) = qBlue(rgb);
CV_IMAGE_ELEM( IplImageBuffer, uchar, y, x*3+1 ) = qGreen(rgb);
CV_IMAGE_ELEM( IplImageBuffer, uchar, y, x*3+2 ) = qRed(rgb);
}
}
return IplImageBuffer;
}
/*将opecv的图片转为qimage格式*/
QImage *Widget::IplImageToQImage(IplImage *img)
{
QImage *qmg;
uchar *imgData=(uchar *)img->imageData;
qmg = new QImage(imgData,img->width,img->height,QImage::Format_RGB888);
*qmg=qmg->rgbSwapped(); //BGR格式转RGB
return qmg;
}
//显示检测的结果
void Widget::show_face(IplImage* img)
{
uchar *imgData=(uchar *)img->imageData;
QImage my_image=QImage(imgData,img->width,img->height,QImage::Format_RGB888);
my_image=my_image.rgbSwapped(); //BGR格式转RGB
QPixmap my_pix; //创建画图类
my_pix.convertFromImage(my_image);
/*在控件上显示*/
ui->label_display->setPixmap(my_pix);
}
//开始采集
void Widget::on_pushButton_Start_clicked()
{
//设置当前选择的摄像头
videoaudioencode_0.camera=video_dev_list.at(ui->comboBox_video_0->currentIndex());
Stop_VideoAudioEncode_0(true);
Start_VideoAudioEncode_Thread_0();
}
//析构函数
VideoReadThread_0::~VideoReadThread_0()
{
}
//停止视频采集
void VideoReadThread_0::stop()
{
qDebug()<<"停止视频采集--stop";
if(camera)
{
camera->stop();
delete camera;
camera=nullptr;
}
if(m_pProbe)
{
delete m_pProbe;
m_pProbe=nullptr;
}
}
//执行线程
void VideoReadThread_0::run()
{
stop();
Camear_Init();
qDebug()<<"摄像头开始采集数据";
}
void VideoReadThread_0::Camear_Init()
{
/*创建摄像头对象，根据选择的摄像头打开*/
camera = new QCamera(videoaudioencode_0.camera);
m_pProbe = new QVideoProbe;
if(m_pProbe != nullptr)
{
m_pProbe->setSource(camera); // Returns true, hopefully.
connect(m_pProbe, SIGNAL(videoFrameProbed(QVideoFrame)),this, SLOT(slotOnProbeFrame(QVideoFrame)), Qt::QueuedConnection);
}
/*配置摄像头捕 QCamera *camera;
QVideoProbe *m_pProbe;获模式为帧捕获模式*/
//camera->setCaptureMode(QCamera::CaptureStillImage); //如果在Linux系统下运行就这样设置
camera->setCaptureMode(QCamera::CaptureVideo);//如果在android系统下运行就这样设置
/*启动摄像头*/
camera->start();
/*设置摄像头的采集帧率和分辨率*/
QCameraViewfinderSettings settings;
settings.setPixelFormat(QVideoFrame::Format_YUYV); //设置像素格式 Android上只支持NV21格式
settings.setResolution(QSize(VIDEO_WIDTH,VIDEO_HEIGHT)); //设置摄像头的分辨率
camera->setViewfinderSettings(settings);
}
/**
* NV21是android相机默认格式
* @param data
* @param rgb
* @param width
* @param height
*/
void NV21_TO_RGB24(unsigned char *yuyv, unsigned char *rgb, int width, int height)
{
const int nv_start = width * height ;
int index = 0, rgb_index = 0;
uint8_t y, u, v;
int r, g, b, nv_index = 0,i, j;
for(i = 0; i < height; i++){
for(j = 0; j < width; j ++){
//nv_index = (rgb_index / 2 - width / 2 * ((i + 1) / 2)) * 2;
nv_index = i / 2 * width + j - j % 2;
y = yuyv[rgb_index];
u = yuyv[nv_start + nv_index ];
v = yuyv[nv_start + nv_index + 1];
r = y + (140 * (v-128))/100; //r
g = y - (34 * (u-128))/100 - (71 * (v-128))/100; //g
b = y + (177 * (u-128))/100; //b
if(r > 255) r = 255;
if(g > 255) g = 255;
if(b > 255) b = 255;
if(r < 0) r = 0;
if(g < 0) g = 0;
if(b < 0) b = 0;
index = rgb_index % width + (height - i - 1) * width;
//rgb[index * 3+0] = b;
//rgb[index * 3+1] = g;
//rgb[index * 3+2] = r;
//颠倒图像
//rgb[height * width * 3 - i * width * 3 - 3 * j - 1] = b;
//rgb[height * width * 3 - i * width * 3 - 3 * j - 2] = g;
//rgb[height * width * 3 - i * width * 3 - 3 * j - 3] = r;
//正面图像
rgb[i * width * 3 + 3 * j + 0] = b;
rgb[i * width * 3 + 3 * j + 1] = g;
rgb[i * width * 3 + 3 * j + 2] = r;
rgb_index++;
}
}
}
/*
函数功能: 将YUV数据转为RGB格式
函数参数:
unsigned char *yuv_buffer: YUV源数据
unsigned char *rgb_buffer: 转换之后的RGB数据
int iWidth,int iHeight : 图像的宽度和高度
*/
void yuyv_to_rgb(unsigned char *yuv_buffer,unsigned char *rgb_buffer,int iWidth,int iHeight)
{
int x;
int z=0;
unsigned char *ptr = rgb_buffer;
unsigned char *yuyv= yuv_buffer;
for (x = 0; x < iWidth*iHeight; x++)
{
int r, g, b;
int y, u, v;
if (!z)
y = yuyv[0] << 8;
else
y = yuyv[2] << 8;
u = yuyv[1] - 128;
v = yuyv[3] - 128;
r = (y + (359 * v)) >> 8;
g = (y - (88 * u) - (183 * v)) >> 8;
b = (y + (454 * u)) >> 8;
*(ptr++) = (r > 255) ? 255 : ((r < 0) ? 0 : r);
*(ptr++) = (g > 255) ? 255 : ((g < 0) ? 0 : g);
*(ptr++) = (b > 255) ? 255 : ((b < 0) ? 0 : b);
if(z++)
{
z = 0;
yuyv += 4;
}
}
}
void VideoReadThread_0::slotOnProbeFrame(const QVideoFrame &frame)
{
QVideoFrame cloneFrame(frame);
cloneFrame.map(QAbstractVideoBuffer::ReadOnly);
//qDebug()<<"height:"<<cloneFrame.height();
//qDebug()<<"width:"<<cloneFrame.width();
//qDebug()<<"bytesPerLine:"<<cloneFrame.bytesPerLine();
//qDebug()<<"mappedBytes:"<<cloneFrame.mappedBytes();
//qDebug()<<"pixelFormat:"<<cloneFrame.pixelFormat();
unsigned char rgb_buffer[VIDEO_WIDTH*VIDEO_HEIGHT*3];
if(cloneFrame.pixelFormat()==QVideoFrame::Format_NV21)
{
NV21_TO_RGB24(cloneFrame.bits(),rgb_buffer,cloneFrame.width(),cloneFrame.height());
}
else if(cloneFrame.pixelFormat()==QVideoFrame::Format_YUYV)
{
yuyv_to_rgb(cloneFrame.bits(),rgb_buffer,cloneFrame.width(),cloneFrame.height());
}
else
{
qDebug("当前格式编码为%1,暂时不支持转换.\n");
}
cloneFrame.unmap();
//加载图片数据
QImage image(rgb_buffer,
cloneFrame.width(),
cloneFrame.height(),
QImage::Format_RGB888);
//绘制图片水印
QDateTime dateTime(QDateTime::currentDateTime());
//时间效果: 2020-03-05 16:25::04 周一
QString qStr="";
qStr+=dateTime.toString("yyyy-MM-dd hh:mm:ss ddd");
QPainter pp(&image);
QPen pen = QPen(Qt::white);
pp.setPen(pen);
pp.drawText(QPointF(0,20),qStr);
//提取RGB数据
unsigned char *p=rgb_buffer;
for(int i=0;i<image.height();i++)
{
for(int j=0;j<image.width();j++)
{
QRgb rgb=image.pixel(j,i);
*p++=qRed(rgb);
*p++=qGreen(rgb);
*p++=qBlue(rgb);
}
}
emit VideoDataOutput(image); //发送信号
}
//驾驶室:视频刷新显示
void Widget::VideoDataDisplay_0(QImage image)
{
QPixmap my_pixmap;
my_pixmap.convertFromImage(image);
/*在控件上显示*/
ui->label_ImageDisplay_0->setPixmap(my_pixmap);
}
//驾驶室:日志显示
void Widget::Log_Display_0(QString text)
{
Log_Text_Display(ui->plainTextEdit_log_0,text);
}
/*日志显示*/
void Widget::Log_Text_Display(QPlainTextEdit *plainTextEdit_log,QString text)
{
plainTextEdit_log->insertPlainText(text);
//移动滚动条到底部
QScrollBar *scrollbar = plainTextEdit_log->verticalScrollBar();
if(scrollbar)
{
scrollbar->setSliderPosition(scrollbar->maximum());
}
}
//驾驶室:开启所有采集线程
void Widget::Start_VideoAudioEncode_Thread_0()
{
videoRead_Workthread_0->start(); //开启视频采集线程
Init_VideoAudio_WorkClass_0(); //发送初始化信号
}
//驾驶室:退出所有采集线程
void Widget::Stop_VideoAudioEncode_0(bool flag)
{
if(flag==true)
{
Stop_AudioVideo0_work_0(); //发送信号停止摄像头
QThread::msleep(10);
//退出视频采集
videoRead_Workthread_0->quit(); //告诉线程的事件循环以return 0（成功）退出
videoRead_Workthread_0->wait(); //等待线程退出
}
}
void Widget::on_pushButton_update_clicked()
{
UpdateVideoAudiodDevice(ui->comboBox_video_0,ui->plainTextEdit_log_0);
}
/*刷新本机可以的音频设备列表*/
void Widget::UpdateVideoAudiodDevice(
QComboBox *comboBox_video,
QPlainTextEdit *plainTextEdit_log)
{
/*2. 获取摄像头列表*/
video_dev_list.clear();
comboBox_video->clear();
video_dev_list=QCameraInfo::availableCameras();
for(int i=0;i<video_dev_list.size();i++)
{
comboBox_video->addItem(video_dev_list.at(i).deviceName());
}
/*如果没有可用的摄像头设备，按钮不可用*/
if(video_dev_list.size()==0)
{
Log_Text_Display(plainTextEdit_log,"未查询到可用的摄像头设备.\n");
}
}
//停止采集
void Widget::on_pushButton_stop_clicked()
{
Stop_VideoAudioEncode_0(true);
}
void Widget::update()
{
if(ui->label_ImageDisplay_0->pixmap())
opencv_face(ui->label_ImageDisplay_0->pixmap()->toImage());
}widget.h file code:
#ifndef WIDGET_H
#define WIDGET_H
#include <QWidget>
//opencv include
#include <cv.h>
#include <cxcore.h>
#include <highgui.h>
#include <QCamera>
#include <QVideoProbe>
#include <QAbstractVideoSurface>
#include <QVideoProbe>
#include <QThread>
#include <QApplication>
#include <QDebug>
#include <QObject>
#include <QMutex>
#include <QMutexLocker>
#include <QWaitCondition>
#include <QQueue>
#include <QCamera>
#include <QPen>
#include <QPainter>
#include <QRgb>
#include <QDateTime>
#include <QCameraInfo>
#include <QPlainTextEdit>
#include <QScrollBar>
#include <QComboBox>
#include <QTimer>
QT_BEGIN_NAMESPACE
namespace Ui { class Widget; }
QT_END_NAMESPACE
class Widget : public QWidget
{
Q_OBJECT
public:
Widget(QWidget *parent = nullptr);
void opencv_face(QImage qImage);
~Widget();
QList<QCameraInfo> video_dev_list;
void show_face(IplImage* img);
class VideoReadThread_0 *videoRead_WorkClass_0; //视频工作类
QThread *videoRead_Workthread_0; //视频线程
/*驾驶室摄像头*/
void Stop_VideoAudioEncode_0(bool flag);//停止线程
void Start_VideoAudioEncode_Thread_0(); //启动线程
void Log_Text_Display(QPlainTextEdit *plainTextEdit_log,QString text);
void UpdateVideoAudiodDevice(QComboBox *comboBox_video, QPlainTextEdit *plainTextEdit_log);
IplImage *QImageToIplImage(const QImage * qImage);
QImage *IplImageToQImage(IplImage *img);
QTimer timer;
signals:
void Init_VideoAudio_WorkClass_0();
void Stop_AudioVideo0_work_0();
private slots:
void update();
void on_pushButton_Start_clicked();
void Log_Display_0(QString text);
void VideoDataDisplay_0(QImage );
void on_pushButton_update_clicked();
void on_pushButton_stop_clicked();
private:
Ui::Widget *ui;
};
class VideoReadThread_0:public QObject
{
Q_OBJECT
public:
QCamera *camera;
QVideoProbe *m_pProbe;
VideoReadThread_0(QObject* parent=nullptr):QObject(parent){camera=nullptr;m_pProbe=nullptr;}
~VideoReadThread_0();
void Camear_Init(void);
public slots:
void stop();
void run();
void slotOnProbeFrame(const QVideoFrame &frame);
signals:
void VideoDataOutput(QImage); //输出信号
};
//视频音频编码类
class VideoAudioEncode
{
public:
QCameraInfo camera; //当前选择的摄像头
};
//视频输出尺寸
#define VIDEO_WIDTH 640
#define VIDEO_HEIGHT 480
extern class VideoAudioEncode videoaudioencode_0;
#endif // WIDGET_Hmain.cpp file code:
#include "widget.h"
#include <QApplication>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
Widget w;
w.show();
return a.exec();
}UI interface file:
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