How to broadcast Webcam Image stream to multiple devices using Opencv and Flask?

I have the following code. It works well when trying to connect with one device to the server. When two devices connect, only one works the other freezes and gives the following error.

The goal is to broadcast a video stream to multiple devices. Also, is there a way to improve the FPS transmitted and reduce latency with Flask?

CODE

Camera.py

import cv2

class VideoCamera(object):
    def __init__(self):
        # Using OpenCV to capture from device 0. If you have trouble capturing
        # from a webcam, comment the line below out and use a video file
        # instead.
        self.video = cv2.VideoCapture(0)
        # If you decide to use video.mp4, you must have this file in the folder
        # as the main.py.
        # self.video = cv2.VideoCapture('video.mp4')

    def __del__(self):
        self.video.release()

    def get_frame(self):
        success, image = self.video.read()
        # We are using Motion JPEG, but OpenCV defaults to capture raw images,
        # so we must encode it into JPEG in order to correctly display the
        # video stream.
        ret, jpeg = cv2.imencode('.jpg', image)
        return jpeg.tobytes()

Main.py

import os

install_opencv = os.system("pip install flask opencv-python")
print("Install OPENCV-PYTHON: ", install_opencv)


from flask import Flask, render_template, Response
from camera import VideoCamera

app = Flask(__name__)

@app.route('/')
def index():
    return render_template('index.html')

def gen(camera):
    while True:
        frame = camera.get_frame()
        yield (b'--frame\r\n'
               b'Content-Type: image/jpeg\r\n\r\n' + frame + b'\r\n\r\n')

@app.route('/video_feed')
def video_feed():
    return Response(gen(VideoCamera()),
                    mimetype='multipart/x-mixed-replace; boundary=frame')

if __name__ == '__main__':
    app.run(host='0.0.0.0', debug=True)

ERROR

Traceback (most recent call last):
cv2.error: OpenCV(3.4.3) C:\projects\opencv-python\opencv\modules\imgcodecs\src\grfmt_base.cpp:145: error: (-10:Unknown error code -10) Raw image encoder error: Empty JPEG image (DNL not supported) in function 'cv::BaseImageEncoder::throwOnEror'
127.0.0.1 - - [01/Nov/2018 16:16:21] "GET /video_feed HTTP/1.1" 200