有没有办法让管道播放任何视频文件（它也会包含音频）？我曾尝试连接相同的元素：用管道在Gstreamer（Python）中播放音频和视频
filesrc -> decodebin
随着
queue -> audioconvert -> autoaudiosink
和
queue -> autovideoconvert -> autovideosink
这会导致两个问题：
queue不能链接到autovideoconvert 。"pad-added"事件实现pad，尤其是当管道支持音频和视频时。我想知道如何做到这一点，而不需要gst.parse_launch。另外，我希望pieline可以使用任何格式（比如playbin），但不能使用playbin，因为我需要链接其他元素（level和volume）。
另外，有没有办法将元素（例如level）连接到playbin？
我已经建立了一个example video player，使得使用您所描述的元素。
它应该告诉你如何动态地连接垫彼此。
'''
Copyright (c) 2011 Joar Wandborg
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
---
- A response to http://stackoverflow.com/questions/8187257/play-audio-and-video-with-a-pipeline-in-gstreamer-python/8197837
- Like it? Buy me a beer! https://flattr.com/thing/422997/Joar-Wandborg
'''
import gst
import gobject
gobject.threads_init()
import logging
logging.basicConfig()
_log = logging.getLogger(__name__)
_log.setLevel(logging.DEBUG)
class VideoPlayer(object):
'''
Simple video player
'''
source_file = None
def __init__(self, **kwargs):
self.loop = gobject.MainLoop()
if kwargs.get('src'):
self.source_file = kwargs.get('src')
self.__setup()
def run(self):
self.loop.run()
def stop(self):
self.loop.quit()
def __setup(self):
_log.info('Setting up VideoPlayer...')
self.__setup_pipeline()
_log.info('Set up')
def __setup_pipeline(self):
self.pipeline = gst.Pipeline('video-player-pipeline')
# Source element
self.filesrc = gst.element_factory_make('filesrc')
self.filesrc.set_property('location', self.source_file)
self.pipeline.add(self.filesrc)
# Demuxer
self.decoder = gst.element_factory_make('decodebin2')
self.decoder.connect('pad-added', self.__on_decoded_pad)
self.pipeline.add(self.decoder)
# Video elements
self.videoqueue = gst.element_factory_make('queue', 'videoqueue')
self.pipeline.add(self.videoqueue)
self.autovideoconvert = gst.element_factory_make('autovideoconvert')
self.pipeline.add(self.autovideoconvert)
self.autovideosink = gst.element_factory_make('autovideosink')
self.pipeline.add(self.autovideosink)
# Audio elements
self.audioqueue = gst.element_factory_make('queue', 'audioqueue')
self.pipeline.add(self.audioqueue)
self.audioconvert = gst.element_factory_make('audioconvert')
self.pipeline.add(self.audioconvert)
self.autoaudiosink = gst.element_factory_make('autoaudiosink')
self.pipeline.add(self.autoaudiosink)
self.progressreport = gst.element_factory_make('progressreport')
self.progressreport.set_property('update-freq', 1)
self.pipeline.add(self.progressreport)
# Link source and demuxer
linkres = gst.element_link_many(
self.filesrc,
self.decoder)
if not linkres:
_log.error('Could not link source & demuxer elements!\n{0}'.format(
linkres))
linkres = gst.element_link_many(
self.audioqueue,
self.audioconvert,
self.autoaudiosink)
if not linkres:
_log.error('Could not link audio elements!\n{0}'.format(
linkres))
linkres = gst.element_link_many(
self.videoqueue,
self.progressreport,
self.autovideoconvert,
self.autovideosink)
if not linkres:
_log.error('Could not link video elements!\n{0}'.format(
linkres))
self.bus = self.pipeline.get_bus()
self.bus.add_signal_watch()
self.bus.connect('message', self.__on_message)
self.pipeline.set_state(gst.STATE_PLAYING)
def __on_decoded_pad(self, pad, data):
_log.debug('on_decoded_pad: {0}'.format(pad))
if pad.get_caps()[0].to_string().startswith('audio'):
pad.link(self.audioqueue.get_pad('sink'))
else:
pad.link(self.videoqueue.get_pad('sink'))
def __on_message(self, bus, message):
_log.debug(' - MESSAGE: {0}'.format(message))
if __name__ == '__main__':
player = VideoPlayer(
src='/home/joar/Videos/big_buck_bunny_1080p_stereo.avi')
player.run()
queue不是源元素，您需要有uridecodebin或decodebin或类似于源元素的东西。
这是gst-launch格式的示例流水线。
uridecodebin \
uri="file:///home/joar/Dropbox/Music/04 - Deadmau5 - Clockwork (Jonas Steur Remix).mp3" \
! audioconvert ! autoaudiosink
这意味着，在管道有
uridecodebin - 解码斌，能够解码无论源文件是在GStreamer兼容，与uri属性设置为file:///home/joar/Dropbox/Music/04 - Deadmau5 - Clockwork (Jonas Steur Remix).mp3的。audioconvert - 转换不同的格式autoaudiosink之间的音频。如果需要，你可以添加uridecodebin和audioconvert之间的queue元素。
我可以做你的描述使用的是什么以下GST-launch命令
gst-launch-0.10 filesrc \
location="/home/joar/Dropbox/Skrillex vs. Adele - Set Fire to Everybody.mov" \
! decodebin name=dmux \
dmux. ! queue ! audioconvert ! autoaudiosink \
dmux. ! queue ! autovideoconvert ! autovideosink
我相信你现在已经实现了。但对于查看你的问题的其他人，我的回答可能会有所帮助。代码如下所示
#!/usr/bin/python
import pygst
pygst.require('0.10')
import gst
import pygtk
pygtk.require('2.0')
import gtk
# this is very important, without this, callbacks from gstreamer thread
# will messed our program up
def on_new_decoded_pad(dbin, pad, islast):
structure_name = pad.get_caps()[0].get_name()
decode = pad.get_parent()
pipeline = decode.get_parent()
if structure_name.startswith("video"):
queuev = pipeline.get_by_name('queuev')
decode.link(queuev)
if structure_name.startswith("audio"):
queuea = pipeline.get_by_name('queuea')
print queuea
decode.link(queuea)
def main():
pipeline = gst.Pipeline('pipleline')
filesrc = gst.element_factory_make("filesrc", "filesrc")
filesrc.set_property('location', '/home/thothadri/Videos/nuclear.avi')
decode = gst.element_factory_make("decodebin", "decode")
queuev = gst.element_factory_make("queue", "queuev")
sink = gst.element_factory_make("autovideosink", "sink")
queuea = gst.element_factory_make("queue", "queuea")
convert = gst.element_factory_make('audioconvert', 'convert')
sink_audio = gst.element_factory_make("autoaudiosink", "sink_audio")
pipeline.add(filesrc,decode,queuev,queuea,convert,sink,sink_audio)
gst.element_link_many(filesrc, decode)
gst.element_link_many(queuev,sink)
gst.element_link_many(queuea,convert,sink_audio)
decode.connect("new-decoded-pad", on_new_decoded_pad)
pipeline.set_state(gst.STATE_PLAYING)
main()
gtk.gdk.threads_init()
gtk.main()
或者您可以通过现在使用的GStreamer 1.0。
在那里，你会发现新的属性audio-filter和video-filter，它可以被用来连接元素（如level)到playbin
使用Python的GObject内省可以这样做一样简单：
level = Gst.ElementFactory.make('level')
playbin = Gst.ElementFactory.make("playbin")
playbin.props.audio_filter = level
完美，但我仍然有一个问题：'新解码垫'已弃用。我如何使用'pad-added'？ –
感谢您的提醒，我已经更新了代码，但还没有时间来测试它，但它应该非常相似 - 只是另一种方法。 – joar
它的工作原理，但你必须把'如果不是sink_pad.is_linked（）：'连接垫之前。此外，我只用音频测试了它，它从不播放。你知道为什么吗？ –