Run python screen capture script in Windows 10 background

Question

I am trying to run the script that captures my screen on the Windows 10 and sends that stream to the flask app. It works fine when I start the script from the Windows CMD, but once I set the script to be started in the background when I login (via Task Manager) it give only the black screen. Same thing happens when I use pythonw to start the script in the background from the CMD.

This is the code that I use:

from flask import Response
from flask import Flask
from flask import render_template
import threading
import numpy
import time
import cv2
import mss
from camera import Camera


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')

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

if __name__ == '__main__':
    app.run(host='10.10.10.1',port=5000, debug=True)

Any advice on how to run this one in the background to capture my screen?

Thank you in advance