Noetic python raw Image publisher (from video)

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Hi everyone, I have spent nearly 2 full days with this problem now and have some extensive research, but just can't figure it out. My apologies for being a burden, I ussually hesitate to waste anyones time. Before asking any questions I give it a good amount of effort.

I'm attempting to read a video stream from a file with opencv and then just publish every single fram on a topic. should be of message type sensor_msgs/Image

Once I have this completed, I will write a subscriber on a remote host, but I have to get the publisher done first, which is where I'm struggling. I have tried the below program, which executes without errors, until I add go into rviz and add new item by topic. that's when the application crashes.

I'm not sure at this point if the publisher works and the problem is on rviz side, or if the publisher is not properly set-up.

PLEASE help !

ROS noetic on Ubuntu 20_04 (native, not in a VM)

#! /usr/bin/env python

import rospy
import cv2
from std_msgs.msg import String
from sensor_msgs.msg import Image
from cv_bridge import CvBridge, CvBridgeError
import sys

VERBOSE=True

bridge = CvBridge()


def main(args):
    rospy.init_node('video_stream', anonymous=True)

    image_publisher = rospy.Publisher("/output/image_raw/stream", Image, queue_size=10)
    video_capture = cv2.VideoCapture('../video/ros.mp4')
    width  = video_capture.get(3)  # float `width`
    height = video_capture.get(4)  # float `height`

    if VERBOSE:
        print("initiated node and publisher")

    while not rospy.is_shutdown():
        try:
            ret, frame = video_capture.read()
            #cv_image = bridge.imgmsg_to_cv2(frame, "bgr8")

            vmsg = Image
            vmsg.header = rospy.Time.now()
            vmsg.height = height
            vmsg.width = width
            vmsg.encoding = "rgb8"
            vmsg.is_bigendian = True
            vmsg.step = 3
            vmsg.data = frame


            # Publish new image
            image_publisher.publish(vmsg)

        except KeyboardInterrupt:
            break
            print("Shutting down")    

    # </while>
    cv2.destroyAllWindows()

    return 0


if __name__ == '__main__':
    try:
        main(sys.argv)
    except KeyboardInterrupt:
        print("Shutting down")

Here is the error output I get when connecting it in rviz:

publish_video.py 
initiated node and publisher
Traceback (most recent call last):
  File "./publish_video.py", line 58, in <module>
    main(sys.argv)
  File "./publish_video.py", line 44, in main
    image_publisher.publish(vmsg)
  File "/opt/ros/noetic/lib/python3/dist-packages/rospy/topics.py", line 882, in publish
    self.impl.publish(data)
  File "/opt/ros/noetic/lib/python3/dist-packages/rospy/topics.py", line 1066, in publish
    serialize_message(b, self.seq, message)
  File "/opt/ros/noetic/lib/python3/dist-packages/rospy/msg.py", line 152, in serialize_message
    msg.serialize(b)
TypeError: serialize() missing 1 required positional argument: 'buff'