Demo/sgi/video/Vreceive.py

   1 #! /usr/bin/env python
   2
   3 # Receive live video UDP packets.
   4 # Usage: Vreceive [port]
   5
   6 import sys
   7 import struct
   8 from socket import *                    # syscalls and support functions
   9 from SOCKET import *                    # <sys/socket.h>
  10 from IN import *                        # <netinet/in.h>
  11 import select
  12 import struct
  13 import gl, GL, DEVICE
  14 sys.path.append('/ufs/guido/src/video')
  15 import LiveVideoOut
  16 import regsub
  17 import getopt
  18
  19 from senddefs import *
  20
  21
  22 # Print usage message and exit(2).
  23
  24 def usage(msg):
  25         print msg
  26         print 'usage: Vreceive [-m mcastgrp] [-p port] [-c type]'
  27         print '-m mcastgrp: multicast group (default ' + `DEFMCAST` + ')'
  28         print '-p port    : port (default ' + `DEFPORT` + ')'
  29         print '-c type    : signal type: rgb8, grey or mono (default rgb8)'
  30         sys.exit(2)
  31
  32
  33 # Main program: parse options and main loop.
  34
  35 def main():
  36
  37         sys.stdout = sys.stderr
  38
  39         group = DEFMCAST
  40         port = DEFPORT
  41         width = DEFWIDTH
  42         height = DEFHEIGHT
  43         vtype = 'rgb8'
  44
  45         try:
  46                 opts, args = getopt.getopt(sys.argv[1:], 'm:p:c:')
  47         except getopt.error, msg:
  48                 usage(msg)
  49
  50         try:
  51                 for opt, optarg in opts:
  52                         if opt == '-p':
  53                                 port = string.atoi(optarg)
  54                         if opt == '-m':
  55                                 group = gethostbyname(optarg)
  56                         if opt == '-c':
  57                                 vtype = optarg
  58         except string.atoi_error, msg:
  59                 usage('bad integer: ' + msg)
  60
  61         s = opensocket(group, port)
  62
  63         gl.foreground()
  64         gl.prefsize(width, height)
  65         wid = gl.winopen('Vreceive')
  66         gl.winconstraints()
  67         gl.qdevice(DEVICE.ESCKEY)
  68         gl.qdevice(DEVICE.WINSHUT)
  69         gl.qdevice(DEVICE.WINQUIT)
  70
  71         lvo = LiveVideoOut.LiveVideoOut(wid, width, height, vtype)
  72
  73         ifdlist = [gl.qgetfd(), s.fileno()]
  74         ofdlist = []
  75         xfdlist = []
  76         timeout = 1.0
  77         selectargs = (ifdlist, ofdlist, xfdlist, timeout)
  78
  79         while 1:
  80
  81                 if gl.qtest():
  82                         dev, val = gl.qread()
  83                         if dev in (DEVICE.ESCKEY, \
  84                                 DEVICE.WINSHUT, DEVICE.WINQUIT):
  85                                 break
  86                         if dev == DEVICE.REDRAW:
  87                                 lvo.reshapewindow()
  88                 elif s.avail():
  89                         data = s.recv(16*1024)
  90                         pos, w, h = struct.unpack('hhh', data[:6])
  91                         if (w, h) <> (width, height):
  92                                 x, y =  gl.getorigin()
  93                                 y = y + height - h
  94                                 gl.winposition(x, x+w-1, y, y+h-1)
  95                                 width, height = w, h
  96                                 lvo.resizevideo(width, height)
  97                         lvo.putnextpacket(pos, data[6:])
  98                 else:
  99                         x = select.select(selectargs)
 100
 101         lvo.close()
 102
 103
 104 # Subroutine to create and properly initialize the receiving socket
 105
 106 def opensocket(group, port):
 107
 108         # Create the socket
 109         s = socket(AF_INET, SOCK_DGRAM)
 110
 111         # Allow multiple copies of this program on one machine
 112         s.setsockopt(SOL_SOCKET, SO_REUSEPORT, 1) # (Not strictly needed)
 113
 114         # Bind the port to it
 115         s.bind('', port)
 116
 117         # Look up the group once
 118         group = gethostbyname(group)
 119
 120         # Construct binary group address
 121         group_bytes = eval(regsub.gsub('\.', ',', group))
 122         grpaddr = 0
 123         for byte in group_bytes: grpaddr = (grpaddr << 8) | byte
 124
 125         # Construct struct mreq from grpaddr and ifaddr
 126         ifaddr = INADDR_ANY
 127         mreq = struct.pack('ll', grpaddr, ifaddr)
 128
 129         # Add group membership
 130         s.setsockopt(IPPROTO_IP, IP_ADD_MEMBERSHIP, mreq)
 131
 132         return s
 133
 134
 135 main()