FFMPEG_BIN = 'ffmpeg'
SOURCE = 'YOUR RTMP INPUT STREAM HERE'
DESTINATION = 'YOUR RTMP PROCESSED OUTPUT STREAM'
FRAME_WIDTH = 1280
FRAME_HEIGHT = 720

import subprocess as sp

cmd_video_only_in = [ FFMPEG_BIN, '-i', SOURCE, '-f', 'image2pipe', '-pix_fmt', 'bgr24', '-vcodec', 'rawvideo','-']
video_input_stream = sp.Popen(cmd_video_only_in, stdout=sp.PIPE, bufsize=FRAME_WIDTH*FRAME_HEIGHT*3, shell=False)

cmd_processed_stream_out = [FFMPEG_BIN,'-y','-thread_queue_size', '1024','-f', 'rawvideo', '-pix_fmt', 'bgr24', '-video_size', str(FRAME_WIDTH)+'X'+str(FRAME_HEIGHT),'-i','-','-itsoffset','-2','-i', SOURCE,'-map','0:v:0','-map','1:a:0','-vcodec','libx264','-pix_fmt','yuv420p','-acodec','copy','-preset','ultrafast','-f','flv',DESTINATION]
processed_output_stream = sp.Popen(cmd_processed_stream_out, stdin=sp.PIPE, shell=False)

import cv2
import numpy as np
import time

while (True):
	raw_image = video_input_stream.stdout.read(FRAME_WIDTH*FRAME_HEIGHT*3)
	image = np.fromstring(raw_image, dtype='uint8')
	image = image.reshape((FRAME_HEIGHT,FRAME_WIDTH,3))
	#Process the image TODO
	processed_output_stream.stdin.write(image.tostring())
	video_input_stream.stdout.flush()
	if cv2.waitKey(25) & 0xFF == ord('q'):
		video_input_stream.terminate()
		processed_output_stream.stdin.close()
		processed_output_stream.terminate()
		break