CV2: How to stream cv2.imshow to flask server?

Question

I have the following code that (1) takes a video (2) analyse for motion and add some text (3) show the output via cv2.imshow (4) finally, publish the output animation on a html page (to be shared with team mates over a intranet/network drive).

How do I pass the cv2.imshow output to the camera in Flask? Also, would anyone know if the Flask webpage can be placed on a shared drive... thus allowing others to view it over intranet (eg over an address such as P:/test/index.html instead of http://127.0.0.1:5000/)?

I've tried looking for solutions by myself, but haven't been able to find answers. Thanks for your kind advice!

cap = cv2.VideoCapture('c:/data/flare2.mp4')
fgbg1 = cv2.createBackgroundSubtractorMOG2()
fgbg2 = cv2.createBackgroundSubtractorMOG2()

while(1):
    ret, frame = cap.read()
    frame1 = frame[0:400, 0:400]
    frame2 = frame[0:400, 400:800]
    
    #FRAME1
    fgmask1 = fgbg1.apply(frame1)
    number_of_white_pix1 = np.sum(fgmask1 == 255)
    fgmask1 = cv2.cvtColor(fgmask1, cv2.COLOR_BGR2RGB  )
    maskcolour1 = cv2.addWeighted(frame1,0,fgmask1,1,0)
    text1 = str(round(number_of_white_pix1/1000,0)) + ' kg / hr flare'

    #FRAME2
    fgmask2 = fgbg2.apply(frame2)
    number_of_white_pix2 = np.sum(fgmask2 == 255)
    fgmask2 = cv2.cvtColor(fgmask2, cv2.COLOR_BGR2RGB  )
    maskcolour2 = cv2.addWeighted(frame2,0,fgmask2,1,0)
    text2 = str(round(number_of_white_pix2/1000,0)) + ' kg / hr flare'
   
    
    font = cv2.FONT_HERSHEY_SIMPLEX 
    cv2.putText(maskcolour1, 
                text1, 
                (50, 50), 
                font, 1, 
                (0, 255, 0), 
                4, 
                cv2.LINE_8)
    
    cv2.putText(maskcolour2, 
                text2, 
                (50, 50), 
                font, 1, 
                (0, 255, 0), 
                4, 
                cv2.LINE_8)
    
    add = cv2.hconcat([maskcolour1, maskcolour2])
    cv2.imshow('combinedall', add)


    k = cv2.waitKey(30) & 0xff
    if k == 27:
        break


##################STREAMING

cap.release()
cv2.destroyAllWindows()


from flask import Flask, render_template, Response
import cv2

app = Flask(__name__)

camera = add ###<<<<is this correct?

def gen_frames():  # generate frame by frame from camera
    while True:
        # Capture frame-by-frame
        success, frame = camera.read()  # read the camera frame
        if not success:
            break
        else:
            ret, buffer = cv2.imencode('.jpg', frame)
            frame = buffer.tobytes()
            yield (b'--frame\r\n'
                   b'Content-Type: image/jpeg\r\n\r\n' + frame + b'\r\n')  # concat frame one by one and show result


@app.route('/video_feed')
def video_feed():
    #Video streaming route. Put this in the src attribute of an img tag
    return Response(gen_frames(), mimetype='multipart/x-mixed-replace; boundary=frame')


@app.route('/')
def index():
    """Video streaming home page."""
    return render_template('index.html')


if __name__ == '__main__':
    app.run(debug=True,use_reloader=False)