Qt 基于海康相机的视频绘图

需求

在视频窗口上进行绘图，包括圆，矩形，扇形等

效果：

 思路：

自己取图然后转成QImage ，再向QWidget 进行渲染，根据以往的经验，无法达到很高的帧率。因此决定使用相机SDK自带的渲染功能，也就是传一个句柄给到sdk。但是这样视频渲染出来了，向上绘制图案，会被视频遮挡住，因此这里采用了两个窗口叠加，然后上层窗口设置透明背景的方式来实现。

底层取图窗口代码：

#ifndef CAMERAWIDGET_H
#define CAMERAWIDGET_H#include <QWidget>
#include <windows.h>
#include <MvCameraControl.h>#include "./util/PSEventController.h"
#include "graphwidget.h"
class CameraWidget : public QWidget
{Q_OBJECT
public:explicit CameraWidget(QWidget *parent = nullptr);~CameraWidget();void updatePos(int x,int y);private:bool findDevice();bool printDeviceInfo(MV_CC_DEVICE_INFO* pstMVDevInfo);void getImage();bool openDevice();bool closeDevice();private:int nRet = MV_OK;void* handle = NULL;MV_CC_DEVICE_INFO_LIST stDeviceList = {0};std::atomic_bool bExit = true;HWND hwnd = NULL;GraphWidget * graphWidget=nullptr;QWidget *videoWidget =nullptr;std::atomic_bool isCapture{false};private:void initData();void mvToQImage(MV_DISPLAY_FRAME_INFO &stDisplayInfo);public slots:void on_psEvent_capture(bool isChecked);void on_psEvent_adjustImage(bool isChecked);void on_psEvent_fixImage(bool isChecked);signals:void capture(QImage image);
};#endif // CAMERAWIDGET_H#include "camerawidget.h"#include <iostream>
#include <mutex>
#include <thread>
#include <QWidget>
#include <QPainter>
#include <QGridLayout>
#include <QStackedLayout>
#include <QDebug>
#include <QGraphicsScene>
#include <QGraphicsView>
#include <QGraphicsItem>CameraWidget::CameraWidget(QWidget *parent): QWidget{parent}
{graphWidget = new GraphWidget(this);graphWidget->setWindowFlags(Qt::FramelessWindowHint|Qt::Dialog|Qt::WindowStaysOnTopHint|Qt::SubWindow);graphWidget->setAttribute(Qt::WA_TranslucentBackground, true);QPalette pal;pal.setColor(QPalette::Window,QColor(0,0,0,0));graphWidget->setAutoFillBackground(true);graphWidget->setPalette(pal);graphWidget->show();hwnd = (HWND)this->winId();openDevice();this->setFixedSize(816,683);graphWidget->setFixedSize(this->size());setUpdatesEnabled(false);setAttribute(Qt::WA_OpaquePaintEvent);initData();
}CameraWidget::~CameraWidget()
{closeDevice();
}bool CameraWidget::findDevice()
{//枚举设备nRet = MV_CC_EnumDevices(MV_GIGE_DEVICE | MV_USB_DEVICE, &stDeviceList);if (MV_OK != nRet){printf("Enum Devices fail! nRet [0x%x]\n", nRet);return false;}if (stDeviceList.nDeviceNum > 0){for (unsigned int i = 0; i < stDeviceList.nDeviceNum; i++){printf("[device %d]:\n", i);MV_CC_DEVICE_INFO* pDeviceInfo = stDeviceList.pDeviceInfo[i];if (NULL == pDeviceInfo){break;}printDeviceInfo(pDeviceInfo);}}else{printf("Find No Devices!\n");return false;}return true;
}bool CameraWidget::openDevice()
{if(!findDevice()){return false;}unsigned int nIndex = 0;if (nIndex >= stDeviceList.nDeviceNum){printf("Invalid device index!\n");return false;}do{//选择设备并创建句柄nRet = MV_CC_CreateHandle(&handle, stDeviceList.pDeviceInfo[nIndex]);if (MV_OK != nRet){printf("Create Handle fail! nRet [0x%x]\n", nRet);break;}// ch:打开设备nRet = MV_CC_OpenDevice(handle);if (MV_OK != nRet){printf("Open Device fail! nRet [0x%x]\n", nRet);break;}// ch:探测网络最佳包大小(只对GigE相机有效)if (stDeviceList.pDeviceInfo[nIndex]->nTLayerType == MV_GIGE_DEVICE){int nPacketSize = MV_CC_GetOptimalPacketSize(handle);if (nPacketSize > 0){nRet = MV_CC_SetIntValue(handle,"GevSCPSPacketSize",nPacketSize);if(nRet != MV_OK){printf("Warning: Set Packet Size fail nRet [0x%x]!", nRet);}}else{printf("Warning: Get Packet Size fail nRet [0x%x]!", nPacketSize);}}//设置触发模式为offnRet = MV_CC_SetEnumValue(handle, "TriggerMode", 0);if (MV_OK != nRet){printf("Set Trigger Mode fail! nRet [0x%x]\n", nRet);break;}// ch:开始取流 | en:Start grab imagenRet = MV_CC_StartGrabbing(handle);if (MV_OK != nRet){printf("Start Grabbing fail! nRet [0x%x]\n", nRet);break;}bExit=false;std::thread t([&](){getImage();});t.detach();return true;}while (0);if (nRet != MV_OK){if (handle != NULL){MV_CC_DestroyHandle(handle);handle = NULL;}}return false;
}bool CameraWidget::closeDevice()
{bExit=true;if (handle == NULL)return true;do{// ch:停止取流 | en:Stop grab imagenRet = MV_CC_StopGrabbing(handle);if (MV_OK != nRet){printf("Stop Grabbing fail! nRet [0x%x]\n", nRet);break;}// ch:关闭设备 | Close devicenRet = MV_CC_CloseDevice(handle);if (MV_OK != nRet){printf("ClosDevice fail! nRet [0x%x]\n", nRet);break;}// ch:销毁句柄 | Destroy handlenRet = MV_CC_DestroyHandle(handle);if (MV_OK != nRet){printf("Destroy Handle fail! nRet [0x%x]\n", nRet);break;}handle = NULL;return true;}while (0);if (nRet != MV_OK){if (handle != NULL){MV_CC_DestroyHandle(handle);handle = NULL;}}return false;
}void CameraWidget::initData()
{PSEventController::subscribe(this,"capture");PSEventController::subscribe(this,"adjustImage");PSEventController::subscribe(this,"fixImage");connect(this,&CameraWidget::capture,this,[&](QImage image){graphWidget->setBackgroundImage(QPixmap::fromImage(image),true);},Qt::UniqueConnection);
}void CameraWidget::on_psEvent_capture(bool isChecked)
{if(!isChecked){QPixmap backgroundImage;graphWidget->setBackgroundImage(backgroundImage,false);}else{isCapture=true;}
}void CameraWidget::on_psEvent_adjustImage(bool isChecked)
{graphWidget->setIsScale(true);
}void CameraWidget::on_psEvent_fixImage(bool isChecked)
{graphWidget->setIsScale(false);
}void CameraWidget::updatePos(int x, int y)
{graphWidget->move(x,y);
}bool CameraWidget::printDeviceInfo(MV_CC_DEVICE_INFO *pstMVDevInfo)
{if (NULL == pstMVDevInfo){printf("The Pointer of pstMVDevInfo is NULL!\n");return false;}if (pstMVDevInfo->nTLayerType == MV_GIGE_DEVICE){int nIp1 = ((pstMVDevInfo->SpecialInfo.stGigEInfo.nCurrentIp & 0xff000000) >> 24);int nIp2 = ((pstMVDevInfo->SpecialInfo.stGigEInfo.nCurrentIp & 0x00ff0000) >> 16);int nIp3 = ((pstMVDevInfo->SpecialInfo.stGigEInfo.nCurrentIp & 0x0000ff00) >> 8);int nIp4 = (pstMVDevInfo->SpecialInfo.stGigEInfo.nCurrentIp & 0x000000ff);// ch:打印当前相机ip和用户自定义名字 | en:print current ip and user defined nameprintf("CurrentIp: %d.%d.%d.%d\n" , nIp1, nIp2, nIp3, nIp4);printf("UserDefinedName: %s\n\n" , pstMVDevInfo->SpecialInfo.stGigEInfo.chUserDefinedName);}else if (pstMVDevInfo->nTLayerType == MV_USB_DEVICE){printf("UserDefinedName: %s\n", pstMVDevInfo->SpecialInfo.stUsb3VInfo.chUserDefinedName);printf("Serial Number: %s\n", pstMVDevInfo->SpecialInfo.stUsb3VInfo.chSerialNumber);printf("Device Number: %d\n\n", pstMVDevInfo->SpecialInfo.stUsb3VInfo.nDeviceNumber);}else{printf("Not support.\n");}return true;
}//std::once_flag flag;
void CameraWidget::getImage()
{int nRet = MV_OK;MV_FRAME_OUT stImageInfo = {0};MV_DISPLAY_FRAME_INFO stDisplayInfo = {0};while(1){nRet = MV_CC_GetImageBuffer(handle, &stImageInfo, 1000);if (nRet == MV_OK){// printf("Get Image Buffer: Width[%d], Height[%d], FrameNum[%d]\n",//  stImageInfo.stFrameInfo.nWidth, stImageInfo.stFrameInfo.nHeight, stImageInfo.stFrameInfo.nFrameNum);if (hwnd){stDisplayInfo.hWnd = hwnd;stDisplayInfo.pData = stImageInfo.pBufAddr;stDisplayInfo.nDataLen = stImageInfo.stFrameInfo.nFrameLen;stDisplayInfo.nWidth = stImageInfo.stFrameInfo.nWidth;stDisplayInfo.nHeight = stImageInfo.stFrameInfo.nHeight;stDisplayInfo.enPixelType = stImageInfo.stFrameInfo.enPixelType;//转qt QImage 给到绘图窗口if(isCapture){mvToQImage(stDisplayInfo);}//调整窗口尺寸//                std::call_once(flag, [&](){//                    int cW = stImageInfo.stFrameInfo.nWidth;//                    int cH = stImageInfo.stFrameInfo.nHeight;//                });MV_CC_DisplayOneFrame(handle, &stDisplayInfo);}nRet = MV_CC_FreeImageBuffer(handle, &stImageInfo);if(nRet != MV_OK){printf("Free Image Buffer fail! nRet [0x%x]\n", nRet);}}else{printf("Get Image fail! nRet [0x%x]\n", nRet);}if(bExit){break;}}
}void CameraWidget::mvToQImage(MV_DISPLAY_FRAME_INFO &stDisplayInfo)
{QImage image;if(stDisplayInfo.enPixelType==PixelType_Gvsp_Mono8){image= QImage(stDisplayInfo.pData, stDisplayInfo.nWidth, stDisplayInfo.nHeight, QImage::Format_Indexed8);}else if(stDisplayInfo.enPixelType==PixelType_Gvsp_RGB8_Packed){image= QImage(stDisplayInfo.pData, stDisplayInfo.nWidth, stDisplayInfo.nHeight, QImage::Format_RGB888);}emit capture(image);isCapture=false;
}

上层绘图窗口代码：

#ifndef CAMERAWIDGET_H
#define CAMERAWIDGET_H#include <QWidget>
#include <windows.h>
#include <MvCameraControl.h>#include "./util/PSEventController.h"
#include "graphwidget.h"
class CameraWidget : public QWidget
{Q_OBJECT
public:explicit CameraWidget(QWidget *parent = nullptr);~CameraWidget();void updatePos(int x,int y);private:bool findDevice();bool printDeviceInfo(MV_CC_DEVICE_INFO* pstMVDevInfo);void getImage();bool openDevice();bool closeDevice();private:int nRet = MV_OK;void* handle = NULL;MV_CC_DEVICE_INFO_LIST stDeviceList = {0};std::atomic_bool bExit = true;HWND hwnd = NULL;GraphWidget * graphWidget=nullptr;QWidget *videoWidget =nullptr;std::atomic_bool isCapture{false};private:void initData();void mvToQImage(MV_DISPLAY_FRAME_INFO &stDisplayInfo);public slots:void on_psEvent_capture(bool isChecked);void on_psEvent_adjustImage(bool isChecked);void on_psEvent_fixImage(bool isChecked);signals:void capture(QImage image);
};#endif // CAMERAWIDGET_H#include "graphwidget.h"
#include <QGridLayout>
#include <QPainter>
#include <QMouseEvent>
#include <QDebug>#include "../graphics/bqgraphicsitem.h"#define VIEW_CENTER viewport()->rect().center()
#define VIEW_WIDTH  viewport()->rect().width()
#define VIEW_HEIGHT viewport()->rect().height()GraphWidget::GraphWidget(QWidget *parent): QGraphicsView{parent}
{setAttribute(Qt::WA_TranslucentBackground);setStyleSheet("background: transparent;border:0px");setWindowFlags(Qt::FramelessWindowHint);setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);setRenderHint(QPainter::Antialiasing);scene = new QGraphicsScene(this);this->setScene(scene);setDragMode(ScrollHandDrag);this->setSceneRect(this->geometry());centerOn(0, 0);initData();
}void GraphWidget::setIsScale(bool newIsScale)
{isScale = newIsScale;if(!isScale){revertSize();}
}void GraphWidget::setBackgroundImage(const QPixmap &newBackgroundImage,bool newIsSetBackground)
{qDebug()<<"setBackgroundImage "<<newIsSetBackground;isSetBackground=newIsSetBackground;if(backgroundItem){scene->removeItem(backgroundItem);backgroundItem=nullptr;}if(isSetBackground){setAttribute(Qt::WA_TranslucentBackground,false);backgroundImage = newBackgroundImage;if(!backgroundImage.isNull()){backgroundItem = scene->addPixmap(backgroundImage);backgroundItem->setPos(-this->width()/2,-this->height()/2);backgroundItem->setZValue(-1000);backgroundItem->setFlags(QGraphicsItem::ItemIsSelectable |QGraphicsItem::ItemIsMovable |QGraphicsItem::ItemIsFocusable);update();}}else{setAttribute(Qt::WA_TranslucentBackground,true);revertSize();}}void GraphWidget::clearItem()
{for(int i=0;i<scene->items().size();i++){QGraphicsItem *item = scene->items().at(i);if(item->zValue()==-1000){continue;}else{scene->removeItem(scene->items().at(i));}}
}void GraphWidget::on_psEvent_addLine(bool isChecked)
{clearItem();BRectangle *m_rectangle = new BRectangle(0, 0, 100, 50, BGraphicsItem::ItemType::Rectangle);scene->addItem(m_rectangle);
}void GraphWidget::on_psEvent_addCircle(bool isChecked)
{clearItem();BConcentricCircle *m_conCircle = new BConcentricCircle(0, 0, 50, 80, BGraphicsItem::ItemType::Concentric_Circle);scene->addItem(m_conCircle);
}void GraphWidget::on_psEvent_addEllipse(bool isChecked)
{clearItem();BEllipse *m_ellipse = new BEllipse(0, 0, 100, 50, BGraphicsItem::ItemType::Ellipse);scene->addItem(m_ellipse);
}void GraphWidget::on_psEvent_addArc(bool isChecked)
{clearItem();BPie *m_pie = new BPie(0, 0, 80, 30, BGraphicsItem::ItemType::Pie);scene->addItem(m_pie);
}void GraphWidget::wheelEvent(QWheelEvent *event)
{if(isScale){static float scale = 1.1;auto angle = event->angleDelta();if(angle.y() > 0){this->scale(scale, scale);}else{this->scale(1/scale, 1/scale);}}
}void GraphWidget::initData()
{PSEventController::subscribe(this,"addLine");PSEventController::subscribe(this,"addCircle");PSEventController::subscribe(this,"addEllipse");PSEventController::subscribe(this,"addArc");
}void GraphWidget::revertSize()
{setTransformationAnchor(QGraphicsView::AnchorViewCenter);QMatrix q;q.setMatrix(1,this->matrix().m12(),this->matrix().m21(),1,this->matrix().dx(),this->matrix().dy());setMatrix(q,false);
}

主窗口移动和缩放时更新视频窗口位置：

void MainWindow::updateGraphWidgetPos()
{if(cameraWidget){QPoint p =  mapToGlobal(cameraWidget->parentWidget()->pos());cameraWidget->updatePos(p.x(),p.y()+22);}
}void MainWindow::resizeEvent(QResizeEvent *e)
{updateGraphWidgetPos();return QWidget::resizeEvent(e);
}void MainWindow::moveEvent(QMoveEvent *e)
{updateGraphWidgetPos();return QWidget::moveEvent(e);
}