Displaying feed from ffmpeg pipe on rqt_image_view

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I am using ffmpeg to pipe video feed from an IP camera into stdout, then using cv_bridge to convert each frame into a compressed image message before publishing it and viewing them on rqt_image_view.

import subprocess
import numpy as np

import rospy
from sensor_msgs.msg import CompressedImage
from cv_bridge import CvBridge, CvBridgeError


class IPStream():
    def __init__(self):
        self.FFMPEG_CMD = "ffmpeg -nostdin -i <rtsp_stream> -pix_fmt bgr24 -r 12 -an -vcodec rawvideo -f rawvideo -".split(" ")
        self.WIDTH = 800
        self.HEIGHT = 600
        self.process = subprocess.Popen(self.FFMPEG_CMD, stdout=subprocess.PIPE, stderr=subprocess.DEVNULL)

        self.bridge = CvBridge()
        self.pub = rospy.Publisher('rtsp_feed', CompressedImage, queue_size=10)

    def ffmpeg_pipe(self):
        while True:
            raw_frame = self.process.stdout.read(self.WIDTH*self.HEIGHT*3)
            frame = np.frombuffer(raw_frame, np.uint8) 
            frame = frame.reshape((self.HEIGHT, self.WIDTH, 3))
            yield frame

    def stream_pub(self):
        generate = self.ffmpeg_pipe()
        while True:
            try:
                frame = next(generate)
                msg = self.bridge.cv2_to_compressed_imgmsg(frame)
                self.pub.publish(msg)
            except CvBridgeError as e:
                print(str(e))

if __name__ == "__main__":
    rospy.init_node("ip_stream")
    camera = IPStream()
    camera.stream_pub()
    try:
        rospy.spin()
    except KeyboardInterrupt:
        camera.process.terminate()

Using rostopic echo /rtsp_feed does provide me with an array, But I am unable to display the compressed image on rqt_image_view. Any idea what is wrong the the above implementation?