我无法从OpenCV的摄像头捕获帧

Question

I am trying to detect eyes but I have another problem. I cannot display the camera frame. The problem can be obvious but I am newbie. A part of my code below:

Here is my EyeDetection.h

#include <opencv2/imgproc/imgproc.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/objdetect/objdetect.hpp>

using namespace cv;

class EyeDetection {
private:
    CascadeClassifier eye_cascade, eyepair_cascade;
public:
    EyeDetection();
    void detect();
}; 

Here is my EyeDetection.cpp

#include "EyeDetection.h"

EyeDetection::EyeDetection() {
    eye_cascade.load("haarcascade_eye.xml");
    eyepair_cascade.load("haarcascade_mcs_eyepair_big.xml");
}

void EyeDetection::detect()
{
    VideoCapture webcam(1); //Webcam number is 1
    if (eyepair_cascade.empty() || eye_cascade.empty() || !(webcam).isOpened())
        return;

    webcam.set(CV_CAP_PROP_FRAME_WIDTH, 800);
    webcam.set(CV_CAP_PROP_FRAME_HEIGHT, 600);

    Mat frame;
    while (1) {
        webcam >> frame;
        if (frame.empty()) continue;
        imshow("asad", frame);
    }
}

And here is my Source.cpp(main):

#include "EyeDetection.h"

using namespace cv;

int main(int argc, char** argv)
{
    EyeDetection e = EyeDetection();
    e.detect();
    return 0;
}

It does not show the camera frame, it shows just a blank gray window. What is the problem?

Answer 1

1. Please check your camera id 1. If you have only one connected camera then please replace the camera id 0 instead 1.

cv2.VideoCapture(1) to cv2.VideoCapture(0)

2. add the waitKey() line add this line at the end of loop

`

while (1) {
        webcam >> frame;
        if (frame.empty()) continue;
        imshow("asad", frame);
        cv2.waitkey(0)
    }

` Maybe to check about waitKey() should be needed for you. Thanks.