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# -*- coding: utf-8 -*-
# Licensed under the MIT license
# http://opensource.org/licenses/mit-license.php
# Copyright 2008, Frank Scholz <coherence@beebits.net>
""" transcoder classes to be used in combination with
a Coherence MediaServer
using GStreamer pipelines for the actually work
and feeding the output into a http response
"""
import pygst
pygst.require('0.10')
import gst
import gobject
gobject.threads_init()
import os.path
import urllib
from twisted.web import resource, server
from twisted.internet import protocol
from coherence import log
import struct
def get_transcoder_name(transcoder):
return transcoder.name
class InternalTranscoder(object):
""" just a class to inherit from and
which we can look for upon creating our
list of available transcoders
"""
class FakeTransformer(gst.Element, log.Loggable):
logCategory = 'faker_datasink'
_sinkpadtemplate = gst.PadTemplate ("sinkpadtemplate",
gst.PAD_SINK,
gst.PAD_ALWAYS,
gst.caps_new_any())
_srcpadtemplate = gst.PadTemplate ("srcpadtemplate",
gst.PAD_SRC,
gst.PAD_ALWAYS,
gst.caps_new_any())
def __init__(self, destination=None, request=None):
gst.Element.__init__(self)
self.sinkpad = gst.Pad(self._sinkpadtemplate, "sink")
self.srcpad = gst.Pad(self._srcpadtemplate, "src")
self.add_pad(self.sinkpad)
self.add_pad(self.srcpad)
self.sinkpad.set_chain_function(self.chainfunc)
self.buffer = ''
self.buffer_size = 0
self.proxy = False
self.got_new_segment = False
self.closed = False
def get_fake_header(self):
return struct.pack(">L4s", 32, 'ftyp') + \
"mp42\x00\x00\x00\x00mp42mp41isomiso2"
def chainfunc(self, pad, buffer):
if self.proxy:
# we are in proxy mode already
self.srcpad.push(buffer)
return gst.FLOW_OK
self.buffer = self.buffer + buffer.data
if not self.buffer_size:
try:
self.buffer_size, a_type = struct.unpack(">L4s", self.buffer[:8])
except:
return gst.FLOW_OK
if len(self.buffer) < self.buffer_size:
# we need to buffer more
return gst.FLOW_OK
buffer = self.buffer[self.buffer_size:]
fake_header = self.get_fake_header()
n_buf = gst.Buffer(fake_header + buffer)
self.proxy = True
self.srcpad.push(n_buf)
return gst.FLOW_OK
gobject.type_register(FakeTransformer)
class DataSink(gst.Element, log.Loggable):
logCategory = 'transcoder_datasink'
_sinkpadtemplate = gst.PadTemplate ("sinkpadtemplate",
gst.PAD_SINK,
gst.PAD_ALWAYS,
gst.caps_new_any())
def __init__(self, destination=None, request=None):
gst.Element.__init__(self)
self.sinkpad = gst.Pad(self._sinkpadtemplate, "sink")
self.add_pad(self.sinkpad)
self.sinkpad.set_chain_function(self.chainfunc)
self.sinkpad.set_event_function(self.eventfunc)
self.destination = destination
self.request = request
if self.destination is not None:
self.destination = open(self.destination, 'wb')
self.buffer = ''
self.data_size = 0
self.got_new_segment = False
self.closed = False
def chainfunc(self, pad, buffer):
if self.closed:
return gst.FLOW_OK
if self.destination is not None:
self.destination.write(buffer.data)
elif self.request is not None:
self.buffer += buffer.data
if len(self.buffer) > 200000:
self.request.write(self.buffer)
self.buffer = ''
else:
self.buffer += buffer.data
self.data_size += buffer.size
return gst.FLOW_OK
def eventfunc(self, pad, event):
if event.type == gst.EVENT_NEWSEGMENT:
if not self.got_new_segment:
self.got_new_segment = True
else:
self.closed = True
elif event.type == gst.EVENT_EOS:
if self.destination is not None:
self.destination.close()
elif self.request is not None:
if len(self.buffer) > 0:
self.request.write(self.buffer)
self.request.finish()
return True
gobject.type_register(DataSink)
class GStreamerPipeline(resource.Resource, log.Loggable):
logCategory = 'gstreamer'
addSlash = True
def __init__(self, pipeline, content_type):
self.pipeline_description = pipeline
self.contentType = content_type
self.requests = []
# if stream has a streamheader (something that has to be prepended
# before any data), then it will be a tuple of GstBuffers
self.streamheader = None
self.parse_pipeline()
resource.Resource.__init__(self)
def parse_pipeline(self):
self.pipeline = gst.parse_launch(self.pipeline_description)
self.appsink = gst.element_factory_make("appsink", "sink")
self.appsink.set_property('emit-signals', True)
self.pipeline.add(self.appsink)
enc = self.pipeline.get_by_name("enc")
enc.link(self.appsink)
self.appsink.connect("new-preroll", self.new_preroll)
self.appsink.connect("new-buffer", self.new_buffer)
self.appsink.connect("eos", self.eos)
def start(self, request=None):
self.info("GStreamerPipeline start %r %r", request,
self.pipeline_description)
self.requests.append(request)
self.pipeline.set_state(gst.STATE_PLAYING)
d = request.notifyFinish()
d.addBoth(self.requestFinished, request)
def new_preroll(self, appsink):
self.debug("new preroll")
buffer = appsink.emit('pull-preroll')
if not self.streamheader:
# check caps for streamheader buffer
caps = buffer.get_caps()
s = caps[0]
if s.has_key("streamheader"):
self.streamheader = s["streamheader"]
self.debug("setting streamheader")
for r in self.requests:
self.debug("writing streamheader")
for h in self.streamheader:
r.write(h.data)
for r in self.requests:
self.debug("writing preroll")
r.write(buffer.data)
def new_buffer(self, appsink):
buffer = appsink.emit('pull-buffer')
if not self.streamheader:
# check caps for streamheader buffers
caps = buffer.get_caps()
s = caps[0]
if s.has_key("streamheader"):
self.streamheader = s["streamheader"]
self.debug("setting streamheader")
for r in self.requests:
self.debug("writing streamheader")
for h in self.streamheader:
r.write(h.data)
for r in self.requests:
r.write(buffer.data)
def eos(self, appsink):
self.info("eos")
for r in self.requests:
r.finish()
self.cleanup()
def getChild(self, name, request):
self.info('getChild %s, %s' % (name, request))
return self
def render_GET(self, request):
self.info('render GET %r' % (request))
request.setResponseCode(200)
if hasattr(self, 'contentType'):
request.setHeader('Content-Type', self.contentType)
request.write('')
headers = request.getAllHeaders()
if('connection' in headers and
headers['connection'] == 'close'):
pass
if self.requests:
if self.streamheader:
self.debug("writing streamheader")
for h in self.streamheader:
request.write(h.data)
self.requests.append(request)
else:
self.parse_pipeline()
self.start(request)
return server.NOT_DONE_YET
def render_HEAD(self, request):
self.info('render HEAD %r' % (request))
request.setResponseCode(200)
request.setHeader('Content-Type', self.contentType)
request.write('')
def requestFinished(self, result, request):
self.info("requestFinished %r" % result)
""" we need to find a way to destroy the pipeline here
"""
#from twisted.internet import reactor
#reactor.callLater(0, self.pipeline.set_state, gst.STATE_NULL)
self.requests.remove(request)
if not self.requests:
self.cleanup()
def on_message(self, bus, message):
t = message.type
print "on_message", t
if t == gst.MESSAGE_ERROR:
#err, debug = message.parse_error()
#print "Error: %s" % err, debug
self.cleanup()
elif t == gst.MESSAGE_EOS:
self.cleanup()
def cleanup(self):
self.info("pipeline cleanup")
self.pipeline.set_state(gst.STATE_NULL)
self.requests = []
self.streamheader = None
class BaseTranscoder(resource.Resource, log.Loggable):
logCategory = 'transcoder'
addSlash = True
def __init__(self, uri, destination=None):
self.info('uri %s %r' % (uri, type(uri)))
if uri[:7] not in ['file://', 'http://']:
uri = 'file://' + urllib.quote(uri) #FIXME
self.uri = uri
self.destination = destination
resource.Resource.__init__(self)
def getChild(self, name, request):
self.info('getChild %s, %s' % (name, request))
return self
def render_GET(self, request):
self.info('render GET %r' % (request))
request.setResponseCode(200)
if hasattr(self, 'contentType'):
request.setHeader('Content-Type', self.contentType)
request.write('')
headers = request.getAllHeaders()
if('connection' in headers and
headers['connection'] == 'close'):
pass
self.start(request)
return server.NOT_DONE_YET
def render_HEAD(self, request):
self.info('render HEAD %r' % (request))
request.setResponseCode(200)
request.setHeader('Content-Type', self.contentType)
request.write('')
def requestFinished(self, result):
self.info("requestFinished %r" % result)
""" we need to find a way to destroy the pipeline here
"""
#from twisted.internet import reactor
#reactor.callLater(0, self.pipeline.set_state, gst.STATE_NULL)
gobject.idle_add(self.cleanup)
def on_message(self, bus, message):
t = message.type
print "on_message", t
if t == gst.MESSAGE_ERROR:
#err, debug = message.parse_error()
#print "Error: %s" % err, debug
self.cleanup()
elif t == gst.MESSAGE_EOS:
self.cleanup()
def cleanup(self):
self.pipeline.set_state(gst.STATE_NULL)
class PCMTranscoder(BaseTranscoder, InternalTranscoder):
contentType = 'audio/L16;rate=44100;channels=2'
name = 'lpcm'
def start(self, request=None):
self.info("PCMTranscoder start %r %r", request, self.uri)
self.pipeline = gst.parse_launch(
"%s ! decodebin ! audioconvert name=conv" % self.uri)
conv = self.pipeline.get_by_name('conv')
caps = gst.Caps("audio/x-raw-int,rate=44100,endianness=4321,channels=2,width=16,depth=16,signed=true")
#FIXME: UGLY. 'filter' is a python builtin!
filter = gst.element_factory_make("capsfilter", "filter")
filter.set_property("caps", caps)
self.pipeline.add(filter)
conv.link(filter)
sink = DataSink(destination=self.destination, request=request)
self.pipeline.add(sink)
filter.link(sink)
self.pipeline.set_state(gst.STATE_PLAYING)
d = request.notifyFinish()
d.addBoth(self.requestFinished)
class WAVTranscoder(BaseTranscoder, InternalTranscoder):
contentType = 'audio/x-wav'
name = 'wav'
def start(self, request=None):
self.info("start %r", request)
self.pipeline = gst.parse_launch(
"%s ! decodebin ! audioconvert ! wavenc name=enc" % self.uri)
enc = self.pipeline.get_by_name('enc')
sink = DataSink(destination=self.destination, request=request)
self.pipeline.add(sink)
enc.link(sink)
#bus = self.pipeline.get_bus()
#bus.connect('message', self.on_message)
self.pipeline.set_state(gst.STATE_PLAYING)
d = request.notifyFinish()
d.addBoth(self.requestFinished)
class MP3Transcoder(BaseTranscoder, InternalTranscoder):
contentType = 'audio/mpeg'
name = 'mp3'
def start(self, request=None):
self.info("start %r", request)
self.pipeline = gst.parse_launch(
"%s ! decodebin ! audioconvert ! lame name=enc" % self.uri)
enc = self.pipeline.get_by_name('enc')
sink = DataSink(destination=self.destination, request=request)
self.pipeline.add(sink)
enc.link(sink)
self.pipeline.set_state(gst.STATE_PLAYING)
d = request.notifyFinish()
d.addBoth(self.requestFinished)
class MP4Transcoder(BaseTranscoder, InternalTranscoder):
""" Only works if H264 inside Quicktime/MP4 container is input
Source has to be a valid uri
"""
contentType = 'video/mp4'
name = 'mp4'
def start(self, request=None):
self.info("start %r", request)
self.pipeline = gst.parse_launch(
"%s ! qtdemux name=d ! queue ! h264parse ! mp4mux name=mux d. ! queue ! mux." % self.uri)
mux = self.pipeline.get_by_name('mux')
sink = DataSink(destination=self.destination, request=request)
self.pipeline.add(sink)
mux.link(sink)
self.pipeline.set_state(gst.STATE_PLAYING)
d = request.notifyFinish()
d.addBoth(self.requestFinished)
class MP2TSTranscoder(BaseTranscoder, InternalTranscoder):
contentType = 'video/mpeg'
name = 'mpegts'
def start(self, request=None):
self.info("start %r", request)
### FIXME mpeg2enc
self.pipeline = gst.parse_launch(
"mpegtsmux name=mux %s ! decodebin2 name=d ! queue ! ffmpegcolorspace ! mpeg2enc ! queue ! mux. d. ! queue ! audioconvert ! twolame ! queue ! mux." % self.uri)
enc = self.pipeline.get_by_name('mux')
sink = DataSink(destination=self.destination, request=request)
self.pipeline.add(sink)
enc.link(sink)
self.pipeline.set_state(gst.STATE_PLAYING)
d = request.notifyFinish()
d.addBoth(self.requestFinished)
class ThumbTranscoder(BaseTranscoder, InternalTranscoder):
""" should create a valid thumbnail according to the DLNA spec
neither width nor height must exceed 160px
"""
contentType = 'image/jpeg'
name = 'thumb'
def start(self, request=None):
self.info("start %r", request)
""" what we actually want here is a pipeline that calls
us when it knows about the size of the original image,
and allows us now to adjust the caps-filter with the
calculated values for width and height
new_width = 160
new_height = 160
if original_width > 160:
new_heigth = int(float(original_height) * (160.0/float(original_width)))
if new_height > 160:
new_width = int(float(new_width) * (160.0/float(new_height)))
elif original_height > 160:
new_width = int(float(original_width) * (160.0/float(original_height)))
"""
try:
type = request.args['type'][0]
except:
type = 'jpeg'
if type == 'png':
self.pipeline = gst.parse_launch(
"%s ! decodebin2 ! videoscale ! video/x-raw-yuv,width=160,height=160 ! pngenc name=enc" % self.uri)
self.contentType = 'image/png'
else:
self.pipeline = gst.parse_launch(
"%s ! decodebin2 ! videoscale ! video/x-raw-yuv,width=160,height=160 ! jpegenc name=enc" % self.uri)
self.contentType = 'image/jpeg'
enc = self.pipeline.get_by_name('enc')
sink = DataSink(destination=self.destination, request=request)
self.pipeline.add(sink)
enc.link(sink)
self.pipeline.set_state(gst.STATE_PLAYING)
d = request.notifyFinish()
d.addBoth(self.requestFinished)
class GStreamerTranscoder(BaseTranscoder):
""" a generic Transcode based on GStreamer
the pipeline which will be parsed upon
calling the start method, as to be set as
the attribute pipeline_description to the
instantiated class
same for the attribute contentType
"""
def start(self, request=None):
self.info("start %r", request)
self.pipeline = gst.parse_launch(self.pipeline_description % self.uri)
enc = self.pipeline.get_by_name('mux')
sink = DataSink(destination=self.destination, request=request)
self.pipeline.add(sink)
enc.link(sink)
self.pipeline.set_state(gst.STATE_PLAYING)
d = request.notifyFinish()
d.addBoth(self.requestFinished)
class ExternalProcessProtocol(protocol.ProcessProtocol):
def __init__(self, caller):
self.caller = caller
def connectionMade(self):
print "pp connection made"
def outReceived(self, data):
#print "outReceived with %d bytes!" % len(data)
self.caller.write_data(data)
def errReceived(self, data):
#print "errReceived! with %d bytes!" % len(data)
print "pp (err):", data.strip()
def inConnectionLost(self):
#print "inConnectionLost! stdin is closed! (we probably did it)"
pass
def outConnectionLost(self):
#print "outConnectionLost! The child closed their stdout!"
pass
def errConnectionLost(self):
#print "errConnectionLost! The child closed their stderr."
pass
def processEnded(self, status_object):
print "processEnded, status %d" % status_object.value.exitCode
print "processEnded quitting"
self.caller.ended = True
self.caller.write_data('')
class ExternalProcessProducer(object):
logCategory = 'externalprocess'
def __init__(self, pipeline, request):
self.pipeline = pipeline
self.request = request
self.process = None
self.written = 0
self.data = ''
self.ended = False
request.registerProducer(self, 0)
def write_data(self, data):
if data:
#print "write %d bytes of data" % len(data)
self.written += len(data)
# this .write will spin the reactor, calling .doWrite and then
# .resumeProducing again, so be prepared for a re-entrant call
self.request.write(data)
if self.request and self.ended:
print "closing"
self.request.unregisterProducer()
self.request.finish()
self.request = None
def resumeProducing(self):
#print "resumeProducing", self.request
if not self.request:
return
if self.process is None:
argv = self.pipeline.split()
executable = argv[0]
argv[0] = os.path.basename(argv[0])
from twisted.internet import reactor
self.process = reactor.spawnProcess(ExternalProcessProtocol(self),
executable, argv, {})
def pauseProducing(self):
pass
def stopProducing(self):
print "stopProducing", self.request
self.request.unregisterProducer()
self.process.loseConnection()
self.request.finish()
self.request = None
class ExternalProcessPipeline(resource.Resource, log.Loggable):
logCategory = 'externalprocess'
addSlash = False
def __init__(self, uri):
self.uri = uri
def getChildWithDefault(self, path, request):
return self
def render(self, request):
print "ExternalProcessPipeline render"
try:
if self.contentType:
request.setHeader('Content-Type', self.contentType)
except AttributeError:
pass
ExternalProcessProducer(self.pipeline_description % self.uri, request)
return server.NOT_DONE_YET
def transcoder_class_wrapper(klass, content_type, pipeline):
def create_object(uri):
transcoder = klass(uri)
transcoder.contentType = content_type
transcoder.pipeline_description = pipeline
return transcoder
return create_object
class TranscoderManager(log.Loggable):
""" singleton class which holds information
about all available transcoders
they are put into a transcoders dict with
their id as the key
we collect all internal transcoders by searching
for all subclasses of InternalTranscoder, the class
will be the value
transcoders defined in the config are parsed and
stored as a dict in the transcoders dict
in the config a transcoder description has to look like this:
*** preliminary, will be extended and might even change without further notice ***
<transcoder>
<pipeline>%s ...</pipeline> <!-- we need a %s here to insert the source uri
(or can we have all the times pipelines we can prepend
with a '%s !')
and an element named mux where we can attach
our sink -->
<type>gstreamer</type> <!-- could be gstreamer or process -->
<name>mpegts</name>
<target>video/mpeg</target>
<fourth_field> <!-- value for the 4th field of the protocolInfo phalanx,
default is '*' -->
</transcoder>
"""
logCategory = 'transcoder_manager'
_instance_ = None # Singleton
def __new__(cls, *args, **kwargs):
""" creates the singleton """
if cls._instance_ is None:
obj = super(TranscoderManager, cls).__new__(cls, *args, **kwargs)
cls._instance_ = obj
return cls._instance_
def __init__(self, coherence=None):
""" initializes the class
it should be called at least once
with the main coherence class passed as an argument,
so we have access to the config
"""
self.transcoders = {}
for transcoder in InternalTranscoder.__subclasses__():
self.transcoders[get_transcoder_name(transcoder)] = transcoder
if coherence is not None:
self.coherence = coherence
try:
transcoders_from_config = self.coherence.config['transcoder']
if isinstance(transcoders_from_config, dict):
transcoders_from_config = [transcoders_from_config]
except KeyError:
transcoders_from_config = []
for transcoder in transcoders_from_config:
# FIXME: is anyone checking if all keys are given ?
pipeline = transcoder['pipeline']
if not '%s' in pipeline:
self.warning("Can't create transcoder %r:"
" missing placehoder '%%s' in 'pipeline'",
transcoder)
continue
try:
transcoder_name = transcoder['name'].decode('ascii')
except UnicodeEncodeError:
self.warning("Can't create transcoder %r:"
" the 'name' contains non-ascii letters",
transcoder)
continue
transcoder_type = transcoder['type'].lower()
if transcoder_type == 'gstreamer':
wrapped = transcoder_class_wrapper(GStreamerTranscoder,
transcoder['target'], transcoder['pipeline'])
elif transcoder_type == 'process':
wrapped = transcoder_class_wrapper(ExternalProcessPipeline,
transcoder['target'], transcoder['pipeline'])
else:
self.warning("unknown transcoder type %r", transcoder_type)
continue
self.transcoders[transcoder_name] = wrapped
#FIXME reduce that to info later
self.warning("available transcoders %r" % self.transcoders)
def select(self, name, uri, backend=None):
# FIXME:why do we specify the name when trying to get it?
if backend is not None:
""" try to find a transcoder provided by the backend
and return that here,
if there isn't one continue with the ones
provided by the config or the internal ones
"""
pass
transcoder = self.transcoders[name](uri)
return transcoder
if __name__ == '__main__':
t = Transcoder(None)
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