调用摄像头，然后将人脸标出结果报错，c++，哪位大佬指点下啊

void faceTest()
{
    String facefile = "F:\\work\\opencv\\build\\etc\\haarcascades\\haarcascade_frontalface_alt.xml";

    //脸部识别分类器
    CascadeClassifier faceCascader;

    if (!faceCascader.load(facefile)) {
        printf("无法加载脸部特征文件:%s", facefile);
        return;
    }

    namedWindow("摄像头", CV_WINDOW_AUTOSIZE);
    VideoCapture capture(0);//打开摄像头

    Mat frame;
    Mat gray;

    vector<Rect> faces;

    int sn = 0;
    //实时读取摄像头的图像帧
    while (capture.read(frame)) {
        //图像变灰 
        cvtColor(frame, gray, COLOR_RGB2GRAY);
        equalizeHist(gray, gray);

        faceCascader.detectMultiScale(gray, faces, 1.2, 3, 0, Size(30, 30));
        for (size_t faceSize = 0; faceSize < faces.size(); faceSize++)
        {
            Rect roi;
            roi.x = faces[static_cast<int>(faceSize)].x;
            roi.y = faces[static_cast<int>(faceSize)].y;
            roi.width = faces[static_cast<int>(faceSize)].width;
            roi.height = faces[static_cast<int>(faceSize)].height;

            Mat faceROI = frame(roi);

            //在人脸区域画一个矩形
            rectangle(frame, faces[static_cast<int>(faceSize)], Scalar(0, 0, 255), 2, 8, 0);

            sn++;
            //将sn整型值转为字符串
            stringstream stream;
            stream << sn;
            //生产一个新的文件名
            String snStr = "F:\\mm\\1\\img-" + stream.str() + ".jpg";
            cout << snStr << endl;
            imwrite(snStr, faceROI);
        }

        imshow("摄像头", frame);

        char key = waitKey(30);
        //按ESC键退出
        if (key == 27) {
            break;
        }
    }

}

int main()
{

    faceTest();

    waitKey(0);
    return 0;
}

在faceCascader.detectMultiScale(gray, faces, 1.2, 3, 0, Size(30, 30));这一句会报错0x00007FF9E591BFF2 (opencv_world341d.dll)处(位于 getphoto.exe 中)引发的异常: 0xC0000005: 读取位置 0x000002C90C45F000 时发生访问冲突。，哪位指点下a