cv：：add 在 openCV 中不起作用

Question

我尝试建立10帧的平均值，所以我尝试:

 .....
cv::Mat frame,outf,resultframe1, resultframe2;
VideoCapture cap(1);
cap>> frame;
resultframe1 = Mat::zeros(frame.rows,frame.cols,CV_32F);
resultframe2 = Mat::zeros(frame.rows,frame.cols,CV_32F);
while(waitKey(0) != 27}{
cap>> frame;
if ( waitKey(1) = 'm'){
for (  int j = 0 ; j <= 10 ; j++){  
cv::add(frame,resultframe1,resultframe2);// here crashes the program ????? 
     ....
 }

}

any Idea我该如何解决这个问题?提前感谢

Answer 1

当OpenCV c++接口中有操作符可用时，不需要显式调用add函数。下面是如何计算指定帧数的平均值。

void main()
{
    cv::VideoCapture cap(-1);
    if(!cap.isOpened())
    {
        cout<<"Capture Not Opened"<<endl;   return;
    }
    //Number of frames to take average of
    const int count = 10;
    const int width = cap.get(CV_CAP_PROP_FRAME_WIDTH);
    const int height = cap.get(CV_CAP_PROP_FRAME_HEIGHT);
    cv::Mat frame, frame32f;
    cv::Mat resultframe = cv::Mat::zeros(height,width,CV_32FC3);
    for(int i=0; i<count; i++)
    {
        cap>>frame;
        if(frame.empty())
        {
            cout<<"Capture Finished"<<endl; break;
        }
        //Convert the input frame to float, without any scaling
        frame.convertTo(frame32f,CV_32FC3); 
        //Add the captured image to the result.
        resultframe += frame32f;
    }
    //Average the frame values.
    resultframe *= (1.0/count);
    /*
     * Result frame is of float data type
     * Scale the values from 0.0 to 1.0 to visualize the image.
     */
    resultframe /= 255.0f;
    cv::imshow("Average",resultframe);
    cv::waitKey();
}

在创建矩阵时始终指定完整类型，例如CV_32FC3而不仅仅是CV_32F。