#! /usr/bin/env python
# Receive live video UDP packets.
# Usage: Vreceive [port]
import sys
import struct
from socket import *# syscalls and support functions
fromSOCKET*#
fromIN*#
select
import struct
import gl, GL, DEVICE
sys.path.append('/ufs/guido/src/video')
import LiveVideoOut
import regsub
import getopt
from senddefs import *
# Print usage message and exit(2).
def usage(msg):
print msg
print 'usage: Vreceive [-m mcastgrp] [-p port] [-c type]'
print '-m mcastgrp: multicast group (default ' + `DEFMCAST` + ')'
print '-p port : port (default ' + `DEFPORT` + ')'
print '-c type : signal type: rgb8, grey or mono (default rgb8)'
sys.exit(2)
# Main program: parse options and main loop.
def main():
sys.stdout = sys.stderr
group = DEFMCAST
port = DEFPORT
width = DEFWIDTH
height = DEFHEIGHT
vtype = 'rgb8'
try:
opts, args = getopt.getopt(sys.argv[1:], 'm:p:c:')
except getopt.error, msg:
usage(msg)
try:
for opt, optarg in opts:
if opt == '-p':
port = string.atoi(optarg)
if opt == '-m':
group = gethostbyname(optarg)
if opt == '-c':
vtype = optarg
except string.atoi_error, msg:
usage('bad integer: ' + msg)
s = opensocket(group, port)
gl.foreground()
gl.prefsize(width, height)
wid = gl.winopen('Vreceive')
gl.winconstraints()
gl.qdevice(DEVICE.ESCKEY)
gl.qdevice(DEVICE.WINSHUT)
gl.qdevice(DEVICE.WINQUIT)
lvo = LiveVideoOut.LiveVideoOut(wid, width, height, vtype)
ifdlist = [gl.qgetfd(), s.fileno()]
ofdlist = []
xfdlist = []
timeout = 1.0
selectargs = (ifdlist, ofdlist, xfdlist, timeout)
while 1:
if gl.qtest():
dev, val = gl.qread()
if dev in (DEVICE.ESCKEY, \
DEVICE.WINSHUT, DEVICE.WINQUIT):
break
if dev == DEVICE.REDRAW:
lvo.reshapewindow()
elif s.avail():
data = s.recv(16*1024)
pos, w, h = struct.unpack('hhh', data[:6])
if (w, h) <> (width, height):
x, y = gl.getorigin()
y = y + height - h
gl.winposition(x, x+w-1, y, y+h-1)
width, height = w, h
lvo.resizevideo(width, height)
lvo.putnextpacket(pos, data[6:])
else:
x = select.select(selectargs)
lvo.close()
# Subroutine to create and properly initialize the receiving socket
def opensocket(group, port):
# Create the socket
s = socket(AF_INET, SOCK_DGRAM)
# Allow multiple copies of this program on one machine
s.setsockopt(SOL_SOCKET, SO_REUSEPORT, 1) # (Not strictly needed)
# Bind the port to it
s.bind('', port)
# Look up the group once
group = gethostbyname(group)
# Construct binary group address
group_bytes = eval(regsub.gsub('\.', ',', group))
grpaddr = 0
for byte in group_bytes: grpaddr = (grpaddr << 8) | byte
# Construct struct mreq from grpaddr and ifaddr
ifaddr = INADDR_ANY
mreq = struct.pack('ll', grpaddr, ifaddr)
# Add group membership
s.setsockopt(IPPROTO_IP, IP_ADD_MEMBERSHIP, mreq)
return s
main()
|