# -*- 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 gi
gi.require_version('Gst', '1.0')
from gi.repository import Gst
from gi.repository import GObject
Gst.init(None)
import os.path
import urllib.request
import urllib.parse
import urllib.error
from twisted.web import resource, server
from twisted.internet import protocol
from coherence import log
import struct
[docs]def get_transcoder_name(transcoder):
return transcoder.name
[docs]class InternalTranscoder(object):
'''Just a class to inherit from and which we can look
for upon creating our list of available transcoders.'''
GObject.type_register(FakeTransformer)
[docs]class DataSink(Gst.Element, log.LogAble):
logCategory = 'transcoder_datasink'
_sinkpadtemplate = Gst.PadTemplate.new(
'sinkpadtemplate',
Gst.PadDirection.SINK,
Gst.PadPresence.ALWAYS,
Gst.Caps.new_any())
def __init__(self, destination=None, request=None):
Gst.Element.__init__(self)
log.LogAble.__init__(self)
self.sinkpad = Gst.Pad.new_from_template(
self._sinkpadtemplate, 'sink')
self.add_pad(self.sinkpad)
self.sinkpad.set_chain_function_full(self.chainfunc)
self.sinkpad.set_event_function_full(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
[docs] def chainfunc(self, pad, inst, buffer):
size = buffer.get_size()
buf_data = buffer.extract_dup(0, size)
if not isinstance(buf_data, bytes):
buf = buffer.encode('ascii')
if self.closed:
return Gst.FlowReturn.OK
if self.destination is not None:
self.destination.write(buf_data)
elif self.request is not None:
self.buffer += buf_data
if len(self.buffer) > 200000:
self.request.write(self.buffer)
self.buffer = b''
else:
self.buffer += buffer.data
self.data_size += size
return Gst.FlowReturn.OK
[docs] def eventfunc(self, pad, inst, event):
if event.type == Gst.Event.new_stream_start('').type:
if not self.got_new_segment:
self.got_new_segment = True
else:
self.closed = True
elif event.type == Gst.Event.new_eos().type:
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)
[docs]class GStreamerPipeline(resource.Resource, log.LogAble):
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)
log.LogAble.__init__(self)
[docs] def parse_pipeline(self):
self.pipeline = Gst.parse_launch(self.pipeline_description)
self.appsink = Gst.ElementFactory.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)
[docs] def start(self, request=None):
self.info(
f'GStreamerPipeline start {request} {self.pipeline_description}')
self.requests.append(request)
self.pipeline.set_state(Gst.State.PLAYING)
d = request.notifyFinish()
d.addBoth(self.requestFinished, request)
[docs] 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 'streamheader' in s:
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)
[docs] 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 'streamheader' in s:
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)
[docs] def eos(self, appsink):
self.info('eos')
for r in self.requests:
r.finish()
self.cleanup()
[docs] def getChild(self, name, request):
self.info(f'getChild {name}, {request}')
return self
[docs] def render_GET(self, request):
self.info(f'render GET {request}')
request.setResponseCode(200)
if hasattr(self, 'contentType'):
request.setHeader(b'Content-Type', self.contentType)
request.write(b'')
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
[docs] def render_HEAD(self, request):
self.info(f'render HEAD {request}')
request.setResponseCode(200)
request.setHeader(b'Content-Type', self.contentType)
request.write(b'')
[docs] def requestFinished(self, result, request):
self.info(f'requestFinished {result}')
# TODO: 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()
[docs] def on_message(self, bus, message):
t = message.type
print('on_message', t)
if t == Gst.Message.ERROR:
# err, debug = message.parse_error()
# print(f'Error: {err}', debug)
self.cleanup()
elif t == Gst.Message.EOS:
self.cleanup()
[docs] def cleanup(self):
self.info('pipeline cleanup')
self.pipeline.set_state(Gst.State.NULL)
self.requests = []
self.streamheader = None
[docs]class BaseTranscoder(resource.Resource, log.LogAble):
logCategory = 'transcoder'
addSlash = True
def __init__(self, uri, destination=None, content_type=None):
if uri[:7] not in ['file://', 'http://']:
uri = 'file://' + urllib.parse.quote(uri) # FIXME
self.uri = uri
self.destination = destination
self.contentType = None
self.pipeline = None
resource.Resource.__init__(self)
log.LogAble.__init__(self)
self.info(f'uri {uri} {type(uri)}')
[docs] def getChild(self, name, request):
self.info(f'getChild {name}, {request}')
return self
[docs] def render_GET(self, request):
self.info(f'render GET {request}')
request.setResponseCode(200)
if self.contentType is not None:
request.setHeader(b'Content-Type', self.contentType)
request.write(b'')
headers = request.getAllHeaders()
if ('connection' in headers and
headers['connection'] == 'close'):
pass
self.start(request)
return server.NOT_DONE_YET
[docs] def render_HEAD(self, request):
self.info(f'render HEAD {request}')
request.setResponseCode(200)
request.setHeader(b'Content-Type', self.contentType)
request.write(b'')
[docs] def requestFinished(self, result):
self.info(f'requestFinished {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)
[docs] def on_message(self, bus, message):
t = message.type
print('on_message', t)
if t == Gst.Message.ERROR:
# err, debug = message.parse_error()
# print(f'Error: {err}', debug)
self.cleanup()
elif t == Gst.Message.EOS:
self.cleanup()
[docs] def cleanup(self):
self.pipeline.set_state(Gst.State.NULL)
[docs] def start(self, request=None):
'''This method should be sub classed for each
class which inherits from BaseTranscoder'''
pass
[docs]class PCMTranscoder(BaseTranscoder, InternalTranscoder):
contentType = 'audio/L16;rate=44100;channels=2'
name = 'lpcm'
[docs] def start(self, request=None):
self.info(f'PCMTranscoder start {request} {self.uri}')
self.pipeline = Gst.parse_launch(
f'{self.uri} ! decodebin ! audioconvert name=conv')
conv = self.pipeline.get_by_name('conv')
caps = Gst.Caps.from_string(
'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.ElementFactory.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)
[docs]class WAVTranscoder(BaseTranscoder, InternalTranscoder):
contentType = 'audio/x-wav'
name = 'wav'
[docs] def start(self, request=None):
self.info(f'start {request}')
self.pipeline = Gst.parse_launch(
f'{self.uri} ! decodebin ! audioconvert ! wavenc name=enc')
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)
[docs]class MP3Transcoder(BaseTranscoder, InternalTranscoder):
contentType = 'audio/mpeg'
name = 'mp3'
[docs] def start(self, request=None):
self.info(f'start {request}')
self.pipeline = Gst.parse_launch(
f'{self.uri} ! decodebin ! audioconvert ! lame name=enc')
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)
[docs]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'
[docs] def start(self, request=None):
self.info(f'start {request}')
self.pipeline = Gst.parse_launch(
f'{self.uri} ! qtdemux name=d ! queue ! h264parse '
f'! mp4mux name=mux d. ! queue ! mux.')
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)
[docs]class MP2TSTranscoder(BaseTranscoder, InternalTranscoder):
contentType = 'video/mpeg'
name = 'mpegts'
[docs] def start(self, request=None):
self.info(f'start {request}')
# FIXME - mpeg2enc
self.pipeline = Gst.parse_launch(
f'mpegtsmux name=mux {self.uri} ! decodebin2 name=d ! queue '
f'! ffmpegcolorspace ! mpeg2enc ! queue ! mux. d. '
f'! queue ! audioconvert ! twolame ! queue ! mux.')
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)
[docs]class ThumbTranscoder(BaseTranscoder, InternalTranscoder):
'''
Should create a valid thumbnail according to the DLNA spec
.. warning:: Neither width nor height must exceed 160px
'''
contentType = 'image/jpeg'
name = 'thumb'
[docs] def start(self, request=None):
self.info(f'start {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 IndexError:
type = 'jpeg'
if type == 'png':
self.pipeline = Gst.parse_launch(
f'{self.uri} ! decodebin2 ! videoscale '
f'! video/x-raw-yuv,width=160,height=160 ! pngenc name=enc')
self.contentType = 'image/png'
else:
self.pipeline = Gst.parse_launch(
f'{self.uri} ! decodebin2 ! videoscale '
f'! video/x-raw-yuv,width=160,height=160 ! jpegenc name=enc')
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)
[docs]class GStreamerTranscoder(BaseTranscoder):
'''
A generic Transcoder based on GStreamer.
'''
pipeline_description = None
'''
The pipeline which will be parsed upon calling the start method,
has to be set as the attribute :attr:`pipeline_description` to
the instantiated class.
'''
[docs] def start(self, request=None):
if self.pipeline_description is None:
raise NotImplementedError(
'Warning: operation cancelled. You must set a value for '
'GStreamerTranscoder.pipeline_description')
self.info(f'start {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)
[docs]class ExternalProcessProtocol(protocol.ProcessProtocol):
def __init__(self, caller):
self.caller = caller
[docs] def connectionMade(self):
print('pp connection made')
[docs] def outReceived(self, data):
# print(f'outReceived with {len(data):d} bytes!')
self.caller.write_data(data)
[docs] def errReceived(self, data):
# print(f'errReceived! with {len(data):d} bytes!')
print('pp (err):', data.strip())
[docs] def inConnectionLost(self):
# print('inConnectionLost! stdin is closed! (we probably did it)')
pass
[docs] def outConnectionLost(self):
# print('outConnectionLost! The child closed their stdout!')
pass
[docs] def errConnectionLost(self):
# print('errConnectionLost! The child closed their stderr.')
pass
[docs] def processEnded(self, status_object):
print(f'processEnded, status {status_object.value.exitCode:d}')
print('processEnded quitting')
self.caller.ended = True
self.caller.write_data('')
[docs]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)
[docs] def write_data(self, data):
if data:
# print(f'write {len(data):d} bytes of 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
[docs] 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, {})
[docs] def pauseProducing(self):
pass
[docs] def stopProducing(self):
print('stopProducing', self.request)
self.request.unregisterProducer()
self.process.loseConnection()
self.request.finish()
self.request = None
[docs]class ExternalProcessPipeline(resource.Resource, log.LogAble):
logCategory = 'externalprocess'
addSlash = False
pipeline_description = None
contentType = None
def __init__(self, uri):
self.uri = uri
resource.Resource.__init__(self)
log.LogAble.__init__(self)
[docs] def getChildWithDefault(self, path, request):
return self
[docs] def render(self, request):
print('ExternalProcessPipeline render')
if self.pipeline_description is None:
raise NotImplementedError(
'Warning: operation cancelled. You must set a value for '
'ExternalProcessPipeline.pipeline_description')
if self.contentType is not None:
request.setHeader(b'Content-Type', self.contentType)
ExternalProcessProducer(self.pipeline_description % self.uri, request)
return server.NOT_DONE_YET
[docs]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
[docs]class TranscoderManager(log.LogAble):
'''
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 ***
.. code-block:: xml
<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)
if 'coherence' in kwargs:
obj.coherence = kwargs['coherence']
cls._instance_ = obj
return cls._instance_
[docs] def __init__(self, coherence=None):
'''
Initializes the class :class:`TranscoderManager`.
It should be called at least once with the main
:class:`~coherence.base.Coherence` class passed as an argument,
so we have access to the config.
'''
log.LogAble.__init__(self)
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 '%s' not 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(
f'unknown transcoder type {transcoder_type}')
continue
self.transcoders[transcoder_name] = wrapped
# FIXME reduce that to info later
self.warning(f'available transcoders {self.transcoders}')
[docs] 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