def __init__(self, app, cookie, payload, jitter_buffer_time=10, session_bw=524288, verbose=0):
#Verbose mode
if verbose:
global VERBOSE
VERBOSE = 1
#Init settings
self.app = app
self.cookie = cookie
self.payload = payload
#Reserved bandwidth
self.session_bw = session_bw
self._pendingDTMF = []
self.ptdict = {}
#seq num send
self.seq = self.genRandom(bits=16)
#seq num receiv
self.jitter_buffer = JitterBuffer()
#Init Random Timestamp and SSRC (<- use to send data)
self.ts = self.genInitTS()
self.ssrc = self.genSSRC()
if VERBOSE:
print(" SSRC: " + str(self.ssrc))
#To check Silent
self._silent = True
# only for debugging -- the way to prevent the sending of RTP packets
# onto the Net is to reopen the audio device with a None (default)
# media sample handler instead of this RTP object as the media sample
#handler.
self.sending = False
#SR infos
self.currentSentBytesTotal = 0
self.currentSentPacketsTotal = 0
#Jitter vars
self.jitter_buffer_flag = True
self.last_sent_time = 0
#Estimation of round trip time
self.rt_time = None
self.rt_time_ref = None
#jitter buffer time in ms (default 10)
self.jitter_buffer_time = jitter_buffer_time
def setUp(self):
self.jitter_buffer = JitterBuffer()
class TestJitterBuffer(unittest.TestCase):
"""Testing function from JitterBuffer"""
def setUp(self):
self.jitter_buffer = JitterBuffer()
def tearDown(self):
pass
def test_init(self):
jitter_buffer = JitterBuffer()
assert(len(jitter_buffer.buffer) == 0), self.fail("Wrong size at initialization")
def test_add(self):
"""Test Adding a packet to jitter buffer"""
packet = RTPPacket(0, 42, 0, "", 0, \
marker=0, \
xhdrtype=None, xhdrdata='')
time = 0
self.jitter_buffer.add([packet, time])
assert(len(self.jitter_buffer.buffer) == 1), \
self.fail("Wrong size afther adding an element")
assert(self.jitter_buffer.buffer[0][1] == 0), self.fail("Wrong value in the buffer for time")
assert(self.jitter_buffer.buffer[0][0].header.seq == 42), self.fail("Wrong value in the buffer for seq num")
packet = RTPPacket(0, 41, 0, "", 0, \
marker=0, \
xhdrtype=None, xhdrdata='')
time = 2
self.jitter_buffer.add([packet, time])
def test_has_seq(self):
"""Testing seq num existenze in the buffer"""
#Adding packets
packet = RTPPacket(0, 42, 0, "", 0, \
marker=0, \
xhdrtype=None, xhdrdata='')
time = 0
self.jitter_buffer.add([packet, time])
packet = RTPPacket(0, 43, 0, "", 0, \
marker=0, \
xhdrtype=None, xhdrdata='')
time = 5
self.jitter_buffer.add([packet, time])
#TEsting values
res = self.jitter_buffer.has_seq(42)
assert(res==True), \
self.fail("Wrong answer from has_seq, can't find an int that is in the buffer")
res = self.jitter_buffer.has_seq(54)
assert(res==False), \
self.fail("Wrong answer from has_seq, can find an int that isn't in the buffer")
def test_get_packets(self):
"""Testing Get Packets from jitter buffer"""
#Adding packets
packet = RTPPacket(0, 42, 0, "", 0, \
marker=0, \
xhdrtype=None, xhdrdata='')
time = 0
self.jitter_buffer.add([packet, time])
packet = RTPPacket(0, 43, 0, "", 0, \
marker=0, \
xhdrtype=None, xhdrdata='')
time = 5
self.jitter_buffer.add([packet, time])
packet = RTPPacket(0, 45, 0, "", 0, \
marker=0, \
xhdrtype=None, xhdrdata='')
time = 8
self.jitter_buffer.add([packet, time])
packet = RTPPacket(0, 44, 0, "", 0, \
marker=0, \
xhdrtype=None, xhdrdata='')
time = 9
self.jitter_buffer.add([packet, time])
res = self.jitter_buffer.get_packets(9)
assert(len(res)==4), self.fail("Wrong size returned")
for i in range(len(res)):
assert(res[i].header.seq==42+i), self.fail("Wrong seq num returned")
assert(len(self.jitter_buffer.buffer)==0), self.fail("Packets have not been erase from jitter buffer")
def test_init(self):
jitter_buffer = JitterBuffer()
assert(len(jitter_buffer.buffer) == 0), self.fail("Wrong size at initialization")
class RTPProtocol(DatagramProtocol):
"""Implementation of the RTP protocol.
Also manages a RTCP instance.
"""
_stunAttempts = 0
_cbDone = None
dest = None
Done = False
def __init__(self, app, cookie, payload, jitter_buffer_time=10, session_bw=524288, verbose=0):
#Verbose mode
if verbose:
global VERBOSE
VERBOSE = 1
#Init settings
self.app = app
self.cookie = cookie
self.payload = payload
#Reserved bandwidth
self.session_bw = session_bw
self._pendingDTMF = []
self.ptdict = {}
#seq num send
self.seq = self.genRandom(bits=16)
#seq num receiv
self.jitter_buffer = JitterBuffer()
#Init Random Timestamp and SSRC (<- use to send data)
self.ts = self.genInitTS()
self.ssrc = self.genSSRC()
if VERBOSE:
print(" SSRC: " + str(self.ssrc))
#To check Silent
self._silent = True
# only for debugging -- the way to prevent the sending of RTP packets
# onto the Net is to reopen the audio device with a None (default)
# media sample handler instead of this RTP object as the media sample
#handler.
self.sending = False
#SR infos
self.currentSentBytesTotal = 0
self.currentSentPacketsTotal = 0
#Jitter vars
self.jitter_buffer_flag = True
self.last_sent_time = 0
#Estimation of round trip time
self.rt_time = None
self.rt_time_ref = None
#jitter buffer time in ms (default 10)
self.jitter_buffer_time = jitter_buffer_time
def createRTPSocket(self, locIP, rport=0, sport=0, needSTUN=False):
""" Start listening on UDP ports for RTP and RTCP.
Returns a Deferred, which is triggered when the sockets are
connected, and any STUN has been completed. The deferred
callback will be passed (extIP, extPort). (The port is the RTP
port.) We don't guarantee a working RTCP port, just RTP.
"""
self.needSTUN = needSTUN
self.rport = rport
self.sport = sport
d = defer.Deferred()
self._socketCompleteDef = d
if rport != 0:
port = rport
else:
port = sport
rtp_port, rtcp_port = self._socketCreationAttempt(locIP, port)
if sport != 0:
if VERBOSE:
if sport != rtp_port :
print("Warning: Selected sending port could not be used, another one has been selected")
print(" Sending port:", rtp_port)
if rport != 0:
if VERBOSE:
if rport != rtp_port :
print("Warning: Selected receiving port could not be used, another one has been selected")
print(" Receiving port:", rtp_port)
self.lastreceivetime = time()
self.init_time = time()*1000
return d
def _socketCreationAttempt(self, locIP, locPort):
"""Creating socket and determining port to be used in the session"""
self.RTCP = rtcp.RTCPProtocol(self, locIP, VERBOSE)
# RTP port must be even, RTCP must be odd
# We select a RTP port at random, and try to get a pair of ports
# next to each other. What fun!
# Note that it's kinda pointless when we're behind a NAT that
# rewrites ports. We can at least send RTCP out in that case,
# but there's no way we'll get any back.
#rtpPort = self.app.getPref('force_rtp_port')
rtpPort = locPort
if not rtpPort:
rtpPort = 11000 + random.randint(0, 9000)
if (rtpPort % 2) == 1:
rtpPort += 1
while True:
try:
self.rtpListener = reactor.listenUDP(rtpPort, self)
except CannotListenError:
rtpPort += 2
continue
else:
break
rtcpPort = rtpPort + 1
#else:
# rtcpPort = self.sport + 1
while True:
try:
self.rtcpListener = reactor.listenUDP(rtcpPort, self.RTCP)
except CannotListenError:
# Not quite right - if it fails, re-do the RTP listen
if self.rport > 0:
self.rtpListener.stopListening()
rtpPort = rtpPort + 2
rtcpPort = rtpPort + 1
continue
else:
break
#self.rtpListener.stopReading()
if self.needSTUN is False:
# The pain can stop right here
self._extRTPPort = rtpPort
self._extIP = locIP
#Passing port to rtcp session ( is it in right place ??)
self.RTCP.peer_port = rtcpPort
d = self._socketCompleteDef
del self._socketCompleteDef
d.callback(self.cookie)
else:
# If the NAT is doing port translation as well, we will just
# have to try STUN and hope that the RTP/RTCP ports are on
# adjacent port numbers. Please, someone make the pain stop.
self.natMapping()
return rtpPort, rtcpPort
def getVisibleAddress(self):
''' returns the local IP address used for RTP (as visible from the
outside world if STUN applies) as ( 'w.x.y.z', rtpPort)
'''
# XXX got an exception at runtime here as mapper hasn't finished yet
#and
#attribute _extIP doesn't exist. I guess this means this should be
#triggered by
#the mapper instead of being a return value... --Zooko 2005-04-05
return (self._extIP, self._extRTPPort)
def natMapping(self):
''' Uses STUN to discover the external address for the RTP/RTCP
ports. deferred is a Deferred to be triggered when STUN is
complete.
'''
if VERBOSE:
print("Nat mapping ...")
# See above comment about port translation.
# We have to do STUN for both RTP and RTCP, and hope we get a sane
# answer.
from .nat import getMapper
d = getMapper()
d.addCallback(self._cb_gotMapper)
return d
def unmapRTP(self):
from .nat import getMapper
if self.needSTUN is False:
return defer.succeed(None)
# Currently removing an already-fired trigger doesn't hurt,
# but this seems likely to change.
try:
reactor.removeSystemEventTrigger(self._shutdownHook)
except:
pass
d = getMapper()
d.addCallback(self._cb_unmap_gotMapper)
return d
def _cb_unmap_gotMapper(self, mapper):
rtpDef = mapper.unmap(self.transport)
rtcpDef = mapper.unmap(self.RTCP.transport)
dl = defer.DeferredList([rtpDef, rtcpDef])
return dl
def _cb_gotMapper(self, mapper):
rtpDef = mapper.map(self.transport)
rtcpDef = mapper.map(self.RTCP.transport)
#TODO check addSystemEventTrigger function of reactor
self._shutdownHook =reactor.addSystemEventTrigger('before',
'shutdown',
self.unmapRTP)
dl = defer.DeferredList([rtpDef, rtcpDef])
dl.addCallback(self.setStunnedAddress).addErrback(log.err)
def setStunnedAddress(self, results):
''' Handle results of the rtp/rtcp STUN. We have to check that
the results have the same IP and usable port numbers
'''
log.msg("got NAT mapping back! %r"%(results), system='rtp')
rtpres, rtcpres = results
if rtpres[0] != defer.SUCCESS or rtcpres[0] != defer.SUCCESS:
# barf out.
log.msg("uh oh, stun failed %r"%(results), system='rtp')
else:
# a=RTCP might help for wacked out RTCP/RTP pairings
# format is something like "a=RTCP:AUDIO 16387"
# See RFC 3605
code1, rtp = rtpres
code2, rtcp = rtcpres
if rtp[0] != rtcp[0]:
print("stun gave different IPs for rtp and rtcp", results)
# We _should_ try and see if we have working rtp and rtcp, but
# this seems almost impossible with most firewalls. So just try
# to get a working rtp port (an even port number is required).
elif False and ((rtp[1] % 2) != 0):
log.error("stun: unusable RTP/RTCP ports %r, retry #%d"%
(results, self._stunAttempts),
system='rtp')
# XXX close connection, try again, tell user
if self._stunAttempts > 8:
# XXX
print("Giving up. Made %d attempts to get a working port" \
% (self._stunAttempts))
self._stunAttempts += 1
defer.maybeDeferred(
self.rtpListener.stopListening).addCallback( \
lambda x:self.rtcpListener.stopListening()).addCallback( \
lambda x:self._socketCreationAttempt())
else:
# phew. working NAT
log.msg("stun: sane NAT for RTP/RTCP; rtp addr: %s" \
% (rtp,), system='rtp')
#Register address and port
self._extIP, self._extRTPPort = rtp
self._stunAttempts = 0
d = self._socketCompleteDef
del self._socketCompleteDef
d.callback(self.cookie)
def connectionRefused(self):
if VERBOSE:
print("RTP got a connection refused, continuing anyway", end=' ')
print(" (May be remote has close his connection...)")
self.Done = True
self.app.drop_call(self.cookie)
def whenDone(self, cbDone):
self._cbDone = cbDone
def stopSendingAndReceiving(self):
self.Done = 1
self.jitter_buffer_flag = False
self.RTCP.send_BYE("Normal quit, ending session")
self.RTCP.stop()
#XXXSHTOOM
#d = self.unmapRTP()
d = defer.succeed(None)
if self.rport > 0:
d.addCallback(lambda x: self.rtpListener.stopListening())
d.addCallback(lambda x: self.rtcpListener.stopListening())
def _send_packet(self, pt, data, marker=0, xhdrtype=None, xhdrdata=''):
if not self.RTCP.we_sent:
#Updating we_sent
self.RTCP.we_sent = True
#Adding itself to senders table
new_member =self.RTCP.member.copy()
loc = self.getVisibleAddress()
#new_member['addr'] = "localhost"
#new_member['port'] = loc[1]+1
self.RTCP.senders_table[self.ssrc] = new_member
#Building packet
packet = RTPPacket(self.ssrc, self.seq, self.ts, data, pt=pt,
marker=marker, xhdrtype=xhdrtype, xhdrdata=xhdrdata)
self.seq += 1
rtp, session = self.app.currentRecordings[self.cookie]
session.seq = self.seq
# Note that seqno gets modulo 2^16 in RTPPacket, so it doesn't need
# to be wrapped at 16 bits here.
if self.seq >= 65536:
self.seq = 1
bytes = packet.netbytes()
## For RTCP sender report.
self.currentSentBytesTotal += len(bytes)
self.currentSentPacketsTotal += 1
for ssrc in self.RTCP.members_table:
if (ssrc != self.ssrc) and (self.RTCP.members_table[ssrc]['rtcp_port'] != 0):
try:
dest = (self.RTCP.members_table[ssrc]['addr'],
self.RTCP.members_table[ssrc]['rtcp_port']-1)
if DEBUG:
print("send RTP to " + str(dest))
self.transport.write(bytes, dest)
except MessageLengthError as e:
print("Cannot write on socket ! Exception e (member: " \
+ str(self.RTCP.members_table[ssrc]))
self.last_sent_time = time()
def _send_cn_packet(self, logit=False, recovery=0):
"""Send empty packet in order to signal a silence and detect any
loss of packet (also usefull fro the first packet"""
assert hasattr(self, 'dest'), "_send_cn_packet called before start %r" \
% (self,)
if logit:
if VERBOSE:
print()
print("Sending CN(%s) to seed firewall to %s:%d" % (self.payload, self.dest[0], self.dest[1]))
self._send_packet(self.payload, chr(127))
def start(self, dest, fp=None):
self.dest = dest
self.jitter_buffer_flag = True
self.Done = False
self.sending = True
# don't use udp connected mode if were sending to localhost, otherwise we won't be able
# to receive on localhost as this sender will also listen on this port, blocking any
# woudl be receiver from using this port
#if hasattr(self.transport, 'connect') and self.dest[0] != '127.0.0.1':
# self.transport.connect(*self.dest)
# Now send a single CN packet to seed any firewalls that might
# need an outbound packet to let the inbound back.
self._send_cn_packet(logit=True)
#Launching jitter buffer polling
if self.rport > 0:
reactor.callInThread(self._polling_jitter_buffer)
#Launching RTCP
self.RTCP.start()
def _polling_jitter_buffer(self):
while self.jitter_buffer_flag:
#if something in the jitter buffer
if len(self.jitter_buffer.buffer) > 0:
#Getting packets from jitter buffer
ref_time = time()*1000 - self.jitter_buffer_time
res = self.jitter_buffer.get_packets(ref_time)
#Checking seq num and silent packets
for packet in res:
ssrc = packet.header.ssrc
#Wrap around seq num
if self.RTCP.members_table[ssrc]['last_seq'] >= 65535:
self.RTCP.members_table[ssrc]['last_seq'] = 1
#Checking seq num
if self.RTCP.members_table[ssrc]['last_seq']+1 \
== packet.header.seq:
#Call app without recovery
self.app.incoming_rtp(self.cookie, packet.header.ts, \
packet, 0)
self.RTCP.members_table[ssrc]['last_seq'] += 1
else:
if self.RTCP.members_table[ssrc]['last_seq'] == 0:
#Call app with recovery journal
self.app.incoming_rtp(self.cookie, packet.header.ts, \
packet, 0)
self.RTCP.members_table[ssrc]['last_seq'] \
= packet.header.seq
else:
#recover infos
self.RTCP.members_table[ssrc]['lost'] += 1
self.RTCP.members_table[ssrc]['last_seq'] \
= packet.header.seq
#logging
if VERBOSE:
line = "Packet Num " \
+ str(self.RTCP.members_table[ssrc]['last_seq']-1)
line += " lost (total lost: " \
+ str(self.RTCP.members_table[ssrc]['lost']) + ")"
line += " for client " \
+ str(self.RTCP.members_table[ssrc]['addr'])
print(line)
#Call app with recovery journal
self.app.incoming_rtp(self.cookie, packet.header.ts,
packet, 1)
sleep(0.001)
def datagramReceived(self, datagram, addr, t=time):
"""Handle packets arriving"""
if self.rport == 0:
return
if not self.checksum(datagram):
if VERBOSE:
print("Warning: Packet received with wrong checksum RTP")
return
#parse the packet
packet = parse_rtppacket(datagram)
#Checking SSRC
ssrc = packet.header.ssrc
if ssrc in self.RTCP.members_table:
cname = self.RTCP.members_table[ssrc]['cname']
else:
cname = ""
if not self.RTCP.check_ssrc(ssrc, addr, "DATA", cname):
if VERBOSE:
print("Warning: Bad SSRC leaving packet on the floor")
return
else:
#Update last_seq and lastreceivetime
self.RTCP.members_table[ssrc]['total_received_bytes'] += len(datagram)
self.RTCP.members_table[ssrc]['total_received_packets'] += 1
self.RTCP.members_table[ssrc]['last_rtp_receive'] = time()
if self.RTCP.members_table[ssrc]['last_seq'] != 0 :
if packet.data == "p":
#Silent without recovery
if DEBUG :
print("silent packet received")
#self.RTCP.members_table[ssrc]['last_seq'] += 1
return
#Testing payload type TODO erase this test
if packet.header.pt == self.payload:
if DEBUG:
print("payload of packet accepted")
#Getting stats
last_ts = self.RTCP.members_table[ssrc]['last_ts']
last_time = self.RTCP.members_table[ssrc]['last_time']
jitter = self.RTCP.members_table[ssrc]['jitter']
#Jitter calculation (rfc 3550 6.4.1)
#S = RTP Timestamp and R is time of arrival
if (last_ts == 0 and last_time == 0) \
or ( (int(time()*1000 - self.init_time) \
- last_time) > JITTER_CALC_TIME_OUT ):
last_ts = packet.header.ts
last_time = int(time()*1000 - self.init_time)
else:
arrival_time = int(time()*1000 - self.init_time)
timestamp = packet.header.ts
delta = float(( arrival_time - last_time ) \
- ( timestamp - last_ts ))
jitter = jitter \
+ ( abs(delta) - jitter ) / 16
self.RTCP.members_table[ssrc]['last_ts'] = timestamp
last_time = self.RTCP.members_table[ssrc]['last_time'] = arrival_time
self.RTCP.members_table[ssrc]['jitter_values'].to_list(jitter)
self.RTCP.members_table[ssrc]['jitter'] = jitter
if self.RTCP.members_table[ssrc]['total_received_packets'] % CHECK_FREQ == 0:
if DEBUG:
print("Estimate jitter time")
jitter_average = self.RTCP.members_table[ssrc]['jitter_values'].average()
total_received = self.RTCP.members_table[ssrc]['total_received_packets']
#Lost rate estimation
lost = self.RTCP.members_table[ssrc]['lost']
lost_rate = (lost / float(total_received + lost)) * 100
#Keep this ?
if lost_rate > MAX_LOST_RATE :
if VERBOSE:
line = "Loosing too much packet !!"
print(line)
#Adjusting latency (based on round trip time/jitter)
#self.test_jitter()
#self.test_delay()
#Adding packet to the jitter buffer
if DEBUG:
print("Adding packet to jitter buffer")
self.jitter_buffer.add([packet, time()*1000])
else:
if VERBOSE:
print("Incompatible payload type")
else:
#this is the first packet
if VERBOSE:
line = "First RTP packet received from " + str(addr)
print(line)
self.RTCP.members_table[ssrc]['last_seq'] = packet.header.seq
##
#Testing function
##
def checksum(self, bytes):
"""Testing that the packet is valid"""
#FIXME: rename for a better name
try:
header = unpack('!BBHII', bytes[:12])
except struct.error as e:
return False
except IndexError as e:
return False
#(version)
version = (header[0]>>6)
if version != 2:
return False
# Payload type
pt = header[1] & 127
if pt != self.payload:
return False
# Padding
padding = (header[0] & 32) and 1 or 0
if padding:
oct_count = len(bytes) - 12
if (oct_count % 4) != 0:
return 0
#Others test ??
# Extension header present
#ext = (hdrpieces[0] & 16) and 1 or 0
#TODO test ext
#si ext, extension mecanism n'est pas present dans session RTP sinon
#return 0
#sinon
#
#TEst : packet must be consistent with CC ? and
#payload type(chek midi payload)
return True
# def test_jitter(self, ):
# jbtime = self.jitter_buffer_time
# #Ajusting jitter buffer size and timestamp
# if int(jitter_average) > int(jbtime) + 3:
# self.app.midi_out.latency += \
# int(jitter_average - jbtime) \
# + 10
# self.jitter_buffer_time += \
# int(jitter_average - jbtime) \
# + 10
# #Logging
# line = "Increasing jitter buffer, now set to "
# line += str(self.jitter_buffer_time)
# line += " ms, jitter estimation is "
# line += str(int(jitter_average)) + " ms"
# log.info(line)
# elif int(jitter_average) < (int(jbtime) - 10) \
# and (jbtime - (jbtime - jitter_average) - 3) \
# > MIN_JITTER_BUFFER_TIME \
# and jbtime > MIN_JITTER_BUFFER_TIME:
# self.app.midi_out.latency -= \
# int(jbtime - jitter_average) - 3
# self.jitter_buffer_time -= \
# int(jbtime - jitter_average) - 3
# #Logging
# line = "Decreasing jitter buffer, now set to "
# line += str(self.jitter_buffer_time)
# line += " ms, jitter estimation is "
# line += str(int(jitter_average)) + " ms"
# log.info(line)
# def test_delay(self):
# if DEBUG:
# print "test delay"
# if self.rt_time != None and self.rt_time_ref != None:
# rt_time = self.rt_time * 1000
# rt_time_ref = self.rt_time_ref * 1000
# if rt_time > rt_time_ref:
# #latency MUST be > to the split between initial
# #rt_time and rt_time_ref
# self.app.midi_out.latency += \
# int(rt_time - rt_time_ref) + 10
# #Logging action
# line = "Updating latency to feet the changing delay"
# line += ", now set to "
# line += str(self.app.midi_out.latency) + " ms"
# log.nfo(line)
# #Update split_ts
# self.split_ts = new_split_ts
# elif rt_time < (rt_time_ref - 40) \
# and (self.app.midi_out.latency > MIN_LATENCY) \
# and ((self.app.midi_out.latency \
# - int(rt_time_ref - rt_time) - 10) \
# > MIN_LATENCY):
# #latency
# self.app.midi_out.latency -= \
# int(rt_time_ref - rt_time) - 10
# #Logging action
# line = "Updating latency to feet the changing delay"
# line += ", now set to "
# line += str(self.app.midi_out.latency) + " ms"
# log.info(line)
# #Update round trip time ref
# self.rt_time_ref = rt_time / 1000
# else:
# if self.rt_time != None:
# if DEBUG:
# print "init rt_ref time"
# self.rt_time_ref = self.rt_time
#
def genSSRC(self):
# Python-ish hack at RFC1889, Appendix A.6
m = hashlib.new('md5')
m.update(str(time()))
m.update(str(id(self)))
if hasattr(os, 'getuid'):
m.update(str(os.getuid()))
m.update(str(os.getgid()))
m.update(str(socket.gethostname()))
hex = m.hexdigest()
nums = hex[:8], hex[8:16], hex[16:24], hex[24:]
nums = [ int(x, 17) for x in nums ]
ssrc = 0
for n in nums: ssrc = ssrc ^ n
ssrc = ssrc & (2**32 - 1)
return ssrc
def genInitTS(self):
# Python-ish hack at RFC1889, Appendix A.6
m = hashlib.new('md5')
m.update(str(self.genSSRC()))
m.update(str(time()))
hex = m.hexdigest()
nums = hex[:8], hex[8:16], hex[16:24], hex[24:]
nums = [ int(x, 16) for x in nums ]
ts = 0
for n in nums: ts = ts ^ n
ts = ts & (2**32 - 1)
return ts
def genRandom(self, bits):
"""Generate up to 128 bits of randomness."""
if os.path.exists("/dev/urandom"):
hex = open('/dev/urandom').read(16).encode("hex")
else:
m = hashlib.new('md5')
m.update(str(time()))
m.update(str(random.random()))
m.update(str(id(self.dest)))
hex = m.hexdigest()
return int(hex[:bits//4],16)
def handle_data(self, pt, timestamp, sample, marker):
if self.Done:
if self._cbDone:
self._cbDone()
return
# We need to keep track of whether we were in silence mode or not -
# when we go from silent->talking, set the marker bit. Other end
# can use this as an excuse to adjust playout buffer.
if not self.sending:
if not hasattr(self, 'warnedaboutthis'):
log.info(("%s.handle_media_sample() should only be called" +
" only when it is in sending mode.") % (self,))
if VERBOSE:
print("WARNING: warnedaboutthis")
self.warnedaboutthis = True
return
incTS = True
#Marker is on first packet after a silent
if not self._silent:
if marker:
marker = 0
self._silent = True
incTS = False
else:
marker = 1
self._silent = False
if incTS:
#Taking care about ts
self.ts += int(timestamp)
# Wrapping
if self.ts >= TWO_TO_THE_32ND:
self.ts = self.ts - TWO_TO_THE_32ND
self._send_packet(pt, sample, marker=marker)
def setUp(self):
self.jitter_buffer = JitterBuffer()
class TestJitterBuffer(unittest.TestCase):
"""Testing function from JitterBuffer"""
def setUp(self):
self.jitter_buffer = JitterBuffer()
def tearDown(self):
pass
def test_init(self):
jitter_buffer = JitterBuffer()
assert len(jitter_buffer.buffer) == 0, self.fail("Wrong size at initialization")
def test_add(self):
"""Test Adding a packet to jitter buffer"""
packet = RTPPacket(0, 42, 0, "", 0, marker=0, xhdrtype=None, xhdrdata="")
time = 0
self.jitter_buffer.add([packet, time])
assert len(self.jitter_buffer.buffer) == 1, self.fail("Wrong size afther adding an element")
assert self.jitter_buffer.buffer[0][1] == 0, self.fail("Wrong value in the buffer for time")
assert self.jitter_buffer.buffer[0][0].header.seq == 42, self.fail("Wrong value in the buffer for seq num")
packet = RTPPacket(0, 41, 0, "", 0, marker=0, xhdrtype=None, xhdrdata="")
time = 2
self.jitter_buffer.add([packet, time])
def test_has_seq(self):
"""Testing seq num existenze in the buffer"""
# Adding packets
packet = RTPPacket(0, 42, 0, "", 0, marker=0, xhdrtype=None, xhdrdata="")
time = 0
self.jitter_buffer.add([packet, time])
packet = RTPPacket(0, 43, 0, "", 0, marker=0, xhdrtype=None, xhdrdata="")
time = 5
self.jitter_buffer.add([packet, time])
# TEsting values
res = self.jitter_buffer.has_seq(42)
assert res == True, self.fail("Wrong answer from has_seq, can't find an int that is in the buffer")
res = self.jitter_buffer.has_seq(54)
assert res == False, self.fail("Wrong answer from has_seq, can find an int that isn't in the buffer")
def test_get_packets(self):
"""Testing Get Packets from jitter buffer"""
# Adding packets
packet = RTPPacket(0, 42, 0, "", 0, marker=0, xhdrtype=None, xhdrdata="")
time = 0
self.jitter_buffer.add([packet, time])
packet = RTPPacket(0, 43, 0, "", 0, marker=0, xhdrtype=None, xhdrdata="")
time = 5
self.jitter_buffer.add([packet, time])
packet = RTPPacket(0, 45, 0, "", 0, marker=0, xhdrtype=None, xhdrdata="")
time = 8
self.jitter_buffer.add([packet, time])
packet = RTPPacket(0, 44, 0, "", 0, marker=0, xhdrtype=None, xhdrdata="")
time = 9
self.jitter_buffer.add([packet, time])
res = self.jitter_buffer.get_packets(9)
assert len(res) == 4, self.fail("Wrong size returned")
for i in range(len(res)):
assert res[i].header.seq == 42 + i, self.fail("Wrong seq num returned")
assert len(self.jitter_buffer.buffer) == 0, self.fail("Packets have not been erase from jitter buffer")