如何在OpenCv C ++中使用“ raspicam :: RaspiCam_Cv”而不是“ CvCapture * capture = cvCaptureFromAVI（a.avi）”

Question

我正在使用C ++编程语言的OpenCv实时检测形状。我找到了一个从文件夹读取并检测形状的代码。但就我而言，相机应实时检测。如何在C ++中使用 raspicam :: RaspiCam_Cv capture; 代替 CvCapture * capture = cvCaptureFromAVI（“ a.avi”）; 。

#include <cv.h>
#include <highgui.h>
using namespace std;

IplImage* imgTracking=0;

int lastX1 = -1;
int lastY1 = -1;

int lastX2 = -1;
int lastY2 = -1;

void trackObject(IplImage* imgThresh){
        CvSeq* contour;  //hold the pointer to a contour
        CvSeq* result;     //hold sequence of points of a contour
        CvMemStorage *storage = cvCreateMemStorage(0); //storage area for all contours

        //finding all contours in the image
        cvFindContours(imgThresh, storage, &contour, sizeof(CvContour), CV_RETR_LIST, CV_CHAIN_APPROX_SIMPLE, cvPoint(0,0));

       //iterating through each contour
       while(contour)
       {
        //obtain a sequence of points of the countour, pointed by the variable 'countour'
       result = cvApproxPoly(contour, sizeof(CvContour), storage, CV_POLY_APPROX_DP, cvContourPerimeter(contour)*0.02, 0);

       //if there are 3 vertices  in the contour and the area of the triangle is more than 100 pixels
       if(result->total==3 && fabs(cvContourArea(result, CV_WHOLE_SEQ))>100 )
       {
              //iterating through each point
              CvPoint *pt[3];
              for(int i=0;i<3;i++){
                   pt[i] = (CvPoint*)cvGetSeqElem(result, i);
              }

               int posX=( pt[0]->x + pt[1]->x + pt[2]->x )/3;
               int posY=( pt[0]->y + pt[1]->y + pt[2]->y )/3;

               if(posX > 360 ){
                   if(lastX1>=0 && lastY1>=0 && posX>=0 && posY>=0){
                       // Draw a red line from the previous point to the current point
                       cvLine(imgTracking, cvPoint(posX, posY), cvPoint(lastX1, lastY1), cvScalar(0,0,255), 4);
                   }

                    lastX1 = posX;
                    lastY1 = posY;  
               }
               else{
                    if(lastX2>=0 && lastY2>=0 && posX>=0 && posY>=0){
                        // Draw a blue line from the previous point to the current point
                         cvLine(imgTracking, cvPoint(posX, posY), cvPoint(lastX2, lastY2), cvScalar(255,0,0), 4);
                     }

                      lastX2 = posX;
                      lastY2 = posY; 
                 }
            }

            //obtain the next contour
            contour = contour->h_next; 
      }

      cvReleaseMemStorage(&storage);
}


int main(){
    //load the video file to the memory
    CvCapture *capture = cvCaptureFromAVI("a.avi");

    if(!capture){
        printf("Capture failure\n");
        return -1;
    }

    IplImage* frame=0;
    frame = cvQueryFrame(capture);           
    if(!frame) return -1;

    //create a blank image and assigned to 'imgTracking' which has the same size of original video
    imgTracking=cvCreateImage(cvGetSize(frame),IPL_DEPTH_8U, 3);
    cvZero(imgTracking); //covert the image, 'imgTracking' to black

    cvNamedWindow("Video");     

    //iterate through each frames of the video     
    while(true){

        frame = cvQueryFrame(capture);           
        if(!frame) break;
        frame=cvCloneImage(frame); 

        //smooth the original image using Gaussian kernel
        cvSmooth(frame, frame, CV_GAUSSIAN,3,3); 

       //converting the original image into grayscale
      IplImage* imgGrayScale = cvCreateImage(cvGetSize(frame), 8, 1); 
      cvCvtColor(frame,imgGrayScale,CV_BGR2GRAY);

       //thresholding the grayscale image to get better results
       cvThreshold(imgGrayScale,imgGrayScale,100,255,CV_THRESH_BINARY_INV);

        //track the possition of the ball
        trackObject(imgGrayScale);

        // Add the tracking image and the frame
        cvAdd(frame, imgTracking, frame);

        cvShowImage("Video", frame);

        //Clean up used images
        cvReleaseImage(&imgGrayScale);            
        cvReleaseImage(&frame);

        //Wait 10mS
        int c = cvWaitKey(10);
        //If 'ESC' is pressed, break the loop
        if((char)c==27 ) break;      
    }

    cvDestroyAllWindows();
    cvReleaseImage(&imgTracking);
    cvReleaseCapture(&capture);     

    return 0;
}

我不能使用raspicam :: RaspiCam_Cv捕获；关键字而不是CvCapture * capture = cvCaptureFromAVI（）;我应该实时检测形状，例如当三角形出现时，然后调用一些函数。请帮助我