Cascade Classifer Is Very Slow

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Hello, I'm trying to make my code more efficent in context of faster FPS but seems I am getting around 35 fps or so... very slow indeed. Can someone please tell me what I have done wrong with this code that is bottlenecking it? I don't have much experience with OpenCV any help appreciated. Code will compile and execution below is from top to bottom, thanks.

//

 called in main class first func
void start_camera::load_face_files(){
    // Load the cascades will trip if path is not correct
    if( !face_cascade.load( face_cascade_name ) ){ printf("--(!)Error loading face cascade from open cv file\n");
  cout<<" \n ERROR: FILE PATH"<<face_cascade_name<<" \n NOT FOUND!"<<endl; // print error if face does not load
    };

    entry_func();
}


void start_camera::entry_func(){
  cap.open(0);

              // 0 = open default camera
    int apiID = cv::CAP_ANY;      // 0 = autodetect default API
    // open selected camera using selected APi
    cap.open(0,apiID);
    // check if we succeeded

    if (!cap.isOpened()) {
        cerr << "ERROR! Unable to open camera\n";

    }
    cout << "Start grabbing" << endl
    << "Press any key to terminate" << endl;

    while(cap.read(frame)){

        if (frame.empty()) {
           cerr << "ERROR! blank frame grabbed\n";
        break;
       }

        imshow("live",frame);

        cam_start(frame);

        if (waitKey(1) >= 0)
            //break;
            cout<<"";
    }

}



void start_camera::cam_start(Mat frame){
     std::vector<Rect> faces;
    Mat frame_gray;
    cvtColor(frame, frame_gray, COLOR_BGR2GRAY);  // Convert to gray scale
    equalizeHist(frame_gray, frame_gray);       // Equalize histogram

    // Detect faces
    face_cascade.detectMultiScale(frame_gray, faces, 1.1, 3, 0|CASCADE_SCALE_IMAGE, Size(30, 30));

    // Iterate over all of the faces
    for( size_t i = 0; i < faces.size(); i++ ) {

        // Find center of faces
        Point center(faces[i].x + faces[i].width/2, faces[i].y + faces[i].height/2);

        // Draw ellipse around face
        ellipse(frame, center, Size(faces[i].width/2, faces[i].height/2),
                0, 0, 360, Scalar( 255, 0, 0 ), 4, 8, 0 );
    }

    imshow(window_name, frame);  // Display frame
}