基于QT和USB摄像头的人脸检测

#include "widget.h" #include "ui_widget.h" #include <QtGui> #include <highgui.h> #ifndef PROPERTY #define PROPERTY #define image_width 320 //图片显示宽度 #define image_height 240 //图片显示高度 #define image_Format QImage::Format_RGB888 //图片显示格式 #define cameraDevice "/dev/video0" //摄像头设备 #define haarXML "./data/haarcascade_frontalface_alt2.xml" //人脸模型级联分类器文件 #define imgSizeScaleSmall 0.5 //图像防缩比例 #define imgSizeScaleBig 2 //图像防缩比例 #endif //PROPERTY Widget::Widget(QWidget *parent) : QWidget(parent), ui(new Ui::Widget) { ui->setupUi(this); imgBuf = (unsigned char *)malloc(image_width * image_height/*QWidget::width()*QWidget::height()*/* 3 * sizeof(char)); frame = new QImage(imgBuf,image_width,image_height,image_Format); //根据存储空间开辟QImage图像 m_camera = new VideoDevice(tr(cameraDevice)); //获取摄像头设备 connect(m_camera, SIGNAL(display_error(QString)), this,SLOT(display_error(QString))); camReturn = m_camera->open_device(); //打开摄像头 if(-1==camReturn) { QMessageBox::warning(this,tr("error"),tr("open /dev/dsp error"),QMessageBox::Yes); m_camera->close_device(); } camReturn = m_camera->init_device(); //初始化摄像头 if(-1==camReturn) { QMessageBox::warning(this,tr("error"),tr("init failed"),QMessageBox::Yes); m_camera->close_device(); } camReturn = m_camera->start_capturing(); //摄像头开始捕获图像 if(-1==camReturn) { QMessageBox::warning(this,tr("error"),tr("start capture failed"),QMessageBox::Yes); m_camera->close_device(); } if(-1==camReturn) { QMessageBox::warning(this,tr("error"),tr("get frame failed"),QMessageBox::Yes); m_camera->stop_capturing(); } //设定时间间隔，对图像界面进行刷新 timer = new QTimer(this); connect(timer,SIGNAL(timeout()),this,SLOT(update())); //update将调用paintEvent timer->start(30); // Storage for the rectangles detected cascadeFile = haarXML; cascade = (CvHaarClassifierCascade *) cvLoad(cascadeFile.toUtf8()); m_FaceCount = 0; storage = cvCreateMemStorage(0); } Widget::~Widget() { delete ui; } void Widget::changeEvent(QEvent *e) { QWidget::changeEvent(e); switch (e->type()) { case QEvent::LanguageChange: ui->retranslateUi(this); break; default: break; } } void Widget::paintEvent(QPaintEvent *) { uchar * pImgBuf; unsigned int len; camReturn = m_camera->get_frame((void **)&pImgBuf,&len); convert_yuv_to_rgb_buffer(pImgBuf,imgBuf,image_width,image_height/*QWidget::width(),QWidget::height()*/); frame->loadFromData((uchar *)imgBuf,/*len*/image_width * image_height * 3 * sizeof(char)); IplImage* src = QImageToIplImage(frame); // IplImage* img = cvLoadImage("./funny.jpg"); if (!src) { printf("img error!"); return; } // cvSaveImage("jason1.jpg", src); double sizeScale = imgSizeScaleSmall; CvSize img_cvsize; img_cvsize.width = src->width * sizeScale; img_cvsize.height = src->height * sizeScale; IplImage* dst = cvCreateImage(img_cvsize, src->depth, src->nChannels); cvResize(src, dst, CV_INTER_LINEAR); detect_and_draw(dst); sizeScale = imgSizeScaleBig; img_cvsize.width = dst->width * sizeScale; img_cvsize.height = dst->height * sizeScale; IplImage* img = cvCreateImage(img_cvsize, dst->depth, dst->nChannels); cvResize(dst, img, CV_INTER_LINEAR); // cvSaveImage("jason2.jpg", img); QImage qimage = QImage((uchar *)img->imageData, img->width,img->height, image_Format); //IplImage为BGR格式，QImage为RGB格式，所以要交换B和R通道显示才正常 //可以用OpenCV的cvConcertImage函数交换，也可以用QImage的rgbSwapped函数交换； qimage = qimage.rgbSwapped(); ui->m_imgLabel->setPixmap(QPixmap::fromImage(qimage)); camReturn = m_camera->unget_frame(); cvReleaseImage(&img); //释放图片内存 cvReleaseImage(&src); } void Widget::display_error(QString err) { QMessageBox::warning(this,tr("error"), err,QMessageBox::Yes); } /*yuv格式转换为rgb格式*/ int Widget::convert_yuv_to_rgb_buffer(unsigned char *yuv, unsigned char *rgb, unsigned int width, unsigned int height) { unsigned int in, out = 0; unsigned int pixel_16; unsigned char pixel_24[3]; unsigned int pixel32; int y0, u, y1, v; for(in = 0; in < width * height * 2; in += 4) { pixel_16 = yuv[in + 3] << 24 | yuv[in + 2] << 16 | yuv[in + 1] << 8 | yuv[in + 0]; y0 = (pixel_16 & 0x000000ff); u = (pixel_16 & 0x0000ff00) >> 8; y1 = (pixel_16 & 0x00ff0000) >> 16; v = (pixel_16 & 0xff000000) >> 24; pixel32 = convert_yuv_to_rgb_pixel(y0, u, v); pixel_24[0] = (pixel32 & 0x000000ff); pixel_24[1] = (pixel32 & 0x0000ff00) >> 8; pixel_24[2] = (pixel32 & 0x00ff0000) >> 16; rgb[out++] = pixel_24[0]; rgb[out++] = pixel_24[1]; rgb[out++] = pixel_24[2]; pixel32 = convert_yuv_to_rgb_pixel(y1, u, v); pixel_24[0] = (pixel32 & 0x000000ff); pixel_24[1] = (pixel32 & 0x0000ff00) >> 8; pixel_24[2] = (pixel32 & 0x00ff0000) >> 16; rgb[out++] = pixel_24[0]; rgb[out++] = pixel_24[1]; rgb[out++] = pixel_24[2]; } return 0; } int Widget::convert_yuv_to_rgb_pixel(int y, int u, int v) { unsigned int pixel32 = 0; unsigned char *pixel = (unsigned char *)&pixel32; int r, g, b; r = y + (1.370705 * (v-128)); g = y - (0.698001 * (v-128)) - (0.337633 * (u-128)); b = y + (1.732446 * (u-128)); 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; pixel[0] = r * 220 / 256; pixel[1] = g * 220 / 256; pixel[2] = b * 220 / 256; return pixel32; } /*yuv格式转换为rgb格式*/ //QImage 转 IplImage 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); //记着释放内存 for (int y = 0; y < height; ++y) { for (int x = 0; x < width; ++x) { QRgb rgb = qImage->pixel(x, y); cvSet2D(IplImageBuffer, y, x, CV_RGB(qRed(rgb), qGreen(rgb), qBlue(rgb))); } } return IplImageBuffer; } //人脸检测函数 void Widget::detect_and_draw(IplImage *img) { 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}} }; double scale = 2.0; 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 ); int i; cvCvtColor( img, gray, CV_BGR2GRAY ); cvResize( gray, small_img, CV_INTER_LINEAR ); cvEqualizeHist( small_img, small_img ); cvClearMemStorage( storage ); if( cascade ) { double t = (double)cvGetTickCount(); CvSeq* faces = cvHaarDetectObjects( small_img, cascade, storage, 1.2, 2, 0, cvSize(30, 30) ); t = (double)cvGetTickCount() - t; printf( "detection time = %gms\n", t/((double)cvGetTickFrequency()*1000.) ); for( i = 0; i < (faces ? faces->total : 0); i++ ) { CvRect* r = (CvRect*)cvGetSeqElem( faces, i ); CvPoint rectP1, rectP2; rectP1.x = cvRound(r->x * scale); rectP1.y = cvRound(r->y * scale); rectP2.x = cvRound((r->x + r->width) * scale); rectP2.y = cvRound((r->y + r->height) * scale); cvRectangl