video_stream_opencv: mjpg_server.py Source File

Go to the documentation of this file.
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
 # Author: Yuki Furuta <furushchev@jsk.imi.i.u-tokyo.ac.jp>
 
 from __future__ import print_function
 import argparse
 import cv2
 import os
 import rospy
 import sys
 import time
 from BaseHTTPServer import BaseHTTPRequestHandler
 from BaseHTTPServer import HTTPServer
 from SocketServer import ThreadingMixIn
 
 
 VIDEO_PATH = None
 
 
 class MJPGStreamHandler(BaseHTTPRequestHandler):
     html_suffix = ['.html']
     mjpg_suffix = ['.mjpg', '.avi', '.mov']
     capture = None
     jpeg_quality = 80
     loop_rate = 20.0
 
     def do_GET(self):
         path, ext = os.path.splitext(self.path)
         if ext in self.html_suffix + self.mjpg_suffix:
             self.send_response(200)
             if ext in self.html_suffix:
                 self.html_response()
             elif ext in self.mjpg_suffix:
                 self.mjpg_response()
         else:
             self.send_response(404)
 
     def html_response(self):
         self.send_header('Content-type', 'text/html')
         self.end_headers()
 
         self.wfile.write('''
         <html>
           <head></head>
           <body>
             <img src="http://127.0.0.1:8080/camera.mjpg"/>
           </body>
         </html>''')
 
     def mjpg_response(self):
         self.send_header(
             'Content-type', 'multipart/x-mixed-replace; boundary=--jpgboundary')
         self.end_headers()
 
         if self.capture is None:
             self.capture = cv2.VideoCapture(VIDEO_PATH)
 
         nframes = self.capture.get(cv2.CAP_PROP_FRAME_COUNT)
         iframe = 0
 
         while True:
             try:
                 ok, img = self.capture.read()
                 if not ok:
                     continue
                 iframe += 1
                 if iframe > nframes:
                     iframe = 0
                     self.capture.open(VIDEO_PATH)
                 ok, img = cv2.imencode('.jpg', img, [cv2.IMWRITE_JPEG_QUALITY, self.jpeg_quality])
                 if not ok:
                     continue
                 jpg = img.tostring()
                 self.wfile.write('--jpgboundary')
                 self.send_header('Content-type', 'image/jpeg')
                 self.send_header('Content-length', str(len(jpg)))
                 self.end_headers()
                 self.wfile.write(jpg)
                 time.sleep(1.0 / self.loop_rate)
             except KeyboardInterrupt:
                 break
 
 
 class ThreadedHTTPServer(ThreadingMixIn, HTTPServer):
     pass
 
 
 def main():
     global VIDEO_PATH
     p = argparse.ArgumentParser()
     p.add_argument('video_path')
     p.add_argument('--port', default=8080, type=int)
 
     if rospy.myargv() == sys.argv:
         argv = sys.argv
         loginfo = print
     else:
         rospy.init_node('mjpg_server')
         argv = rospy.myargv()
         loginfo = rospy.loginfo
 
 
     args = p.parse_args(argv[1:])
 
     VIDEO_PATH = args.video_path
     if not os.path.exists(VIDEO_PATH):
         raise OSError('video not found: {}'.format(VIDEO_PATH))
 
     server = None
     try:
         server = ThreadedHTTPServer(('localhost', args.port), MJPGStreamHandler)
         loginfo('Server Started')
         server.serve_forever()
     except Exception as ex:
         loginfo('Got exception: {}'.format(str(ex)))
     finally:
         if server:
             server.socket.close()
         loginfo('Server Ended')
 
 
 if __name__ == '__main__':
     main()