gstreamer python snips

playbin_about-to-finish.py

#!/usr/bin/env python3

import gi

from urllib.parse import quote

gi.require_version('Gst', '1.0')
gi.require_version('GLib', '2.0')
from gi.repository import GLib, Gst

# mode debugging infos
Gst.debug_set_active(True)
Gst.debug_set_default_threshold(3)

Gst.init(None)

playlist = [
    '/home/user/dev/python/adtv.mp4',
    '/home/user/dev/python/voice.mp4',
    '/home/user/dev/python/andacht.mp4',
]

playbin = Gst.ElementFactory.make('playbin', 'playbin')

def on_about_to_finish(*args):
    url = quote(playlist.pop(0))
    playbin.set_property('uri', 'file://' + url)


playbin.connect('about-to-finish', on_about_to_finish)
url = quote(playlist.pop(0))
playbin.set_property('uri', 'file://' + url)

playbin.seek_simple(Gst.Format.TIME, Gst.SeekFlags.FLUSH, 10 * Gst.SECOND)
playbin.set_state(Gst.State.PLAYING)


loop = GLib.MainLoop()

loop.run()

uridecodebin3_about-to-finish.py

#!/usr/bin/env python3

import gi
import os
import sys
gi.require_version('Gst', '1.0')
gi.require_version('GLib', '2.0')
from gi.repository import GLib, Gst

"""
This example is not working!!!
"""

current_dir = os.path.dirname(os.path.realpath(__file__))
os.environ["GST_DEBUG_DUMP_DOT_DIR"] = current_dir
os.putenv('GST_DEBUG_DUMP_DIR_DIR', current_dir)
os.putenv('GST_DEBUG_NO_COLOR', "1")
os.putenv('GST_DEBUG_FILE', current_dir + '/debug.log')

# mode debugging infos
Gst.debug_set_active(True)
Gst.debug_set_default_threshold(6)

Gst.init(None)


# callback link pads
def on_new_decoded_pad(dbin, pad):
    type = pad.query_caps(None).to_string()
    decode = pad.get_parent()
    pipeline = decode.get_parent()

    if type.startswith("video"):
        video_queue = pipeline.get_by_name("video_queue")
        decode.link(video_queue)
        print("linked video")
    if type.startswith("audio"):
        audio_queue = pipeline.get_by_name("audio_queue")
        decode.link(audio_queue)
        print("linked audio")


playlist = [
    'file:///home/user/dev/python/adtv.mp4',
    'file:///home/user/dev/python/voice.mp4',
    'file:///home/user/dev/python/andacht.mp4',
]

pipe = Gst.Pipeline.new('pipleline')

uri = Gst.ElementFactory.make('uridecodebin3', "uri")
video_queue = Gst.ElementFactory.make('queue', 'video_queue')
audio_queue = Gst.ElementFactory.make('queue', 'audio_queue')
video_convert = Gst.ElementFactory.make('videoconvert', "video_convert")
audio_convert = Gst.ElementFactory.make('audioconvert', 'audio_convert')
video_sink = Gst.ElementFactory.make('autovideosink', 'video_sink')
audio_sink = Gst.ElementFactory.make('autoaudiosink', 'audio_sink')

pipe.add(uri)
pipe.add(video_queue)
pipe.add(audio_queue)
pipe.add(video_convert)
pipe.add(audio_convert)
pipe.add(video_sink)
pipe.add(audio_sink)

video_queue.link(video_convert)
audio_queue.link(audio_convert)
video_convert.link(video_sink)
audio_convert.link(audio_sink)


def on_about_to_finish(*args):
    uri.set_property('uri', playlist.pop(0))
    uri.connect('pad-added', on_new_decoded_pad)


# link decoder to coresponding queue
uri.connect('pad-added', on_new_decoded_pad)

uri.connect('about-to-finish', on_about_to_finish)
uri.set_property('uri', playlist.pop(0))

Gst.debug_bin_to_dot_file(
        pipe,
        Gst.DebugGraphDetails.ALL,
        'debug-graph')

# playbin.seek_simple(Gst.Format.TIME, Gst.SeekFlags.FLUSH, 10 * Gst.SECOND)
pipe.set_state(Gst.State.PLAYING)

loop = GLib.MainLoop()

loop.run()

@jb-alvarado I'm curious if you did any further experiments using gstreamer and playlists/playlist handling in addition to this gist. Obviously you've done a lot of interesting work using ffmpeg and your ffmpeg playout engine repo :-)

Yes I did, but all end in the conclusion that it is more difficult to have A/V sync and it needed more resources then my ffmpeg solution.

A really interesting project is FFdynamic. I think a playout solution based on that could be more powerful. But I'm not a c++ developer, so is more difficult for me to dive in.