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Я искал много примеров использования библиотеки питона GStreamer на Windows, но только те, которые работают хорошо, как это:Play .avi видео с помощью GStreamer 1.0 и Python
#!/usr/bin/env python3
# -*- coding:utf-8 -*-
# GStreamer SDK Tutorials in Python
#
# basic-tutorial-2
#
"""
basic-tutorial-2: GStreamer concepts
http://docs.gstreamer.com/display/GstSDK/Basic+tutorial+2%3A+GStreamer+concepts
"""
import sys
from gi.repository import Gst
Gst.init(None)
# Create the elements
source = Gst.ElementFactory.make("videotestsrc", "source")
sink = Gst.ElementFactory.make("autovideosink", "sink")
# Create the empty pipeline
pipeline = Gst.Pipeline.new("test-pipeline")
if not source or not sink or not pipeline:
print("Not all elements could be created.", file=sys.stderr)
exit(-1)
# Build the pipeline
pipeline.add(source)
pipeline.add(sink)
if not Gst.Element.link(source, sink):
print("Elements could not be linked.", file=sys.stderr)
exit(-1)
# Modify the source's properties
source.set_property("pattern", 0)
# Start playing
ret = pipeline.set_state(Gst.State.PLAYING)
if ret == Gst.StateChangeReturn.FAILURE:
print("Unable to set the pipeline to the playing state.", file=sys.stderr)
exit(-1)
# Wait until error or EOS
bus = pipeline.get_bus()
msg = bus.timed_pop_filtered(
Gst.CLOCK_TIME_NONE, Gst.MessageType.ERROR | Gst.MessageType.EOS)
# Parse message
if (msg):
if msg.type == Gst.MessageType.ERROR:
err, debug = msg.parse_error()
print("Error received from element %s: %s" % (
msg.src.get_name(), err), file=sys.stderr)
print("Debugging information: %s" % debug, file=sys.stderr)
elif msg.type == Gst.MessageType.EOS:
print("End-Of-Stream reached.")
else:
print("Unexpected message received.", file=sys.stderr)
# Free resources
pipeline.set_state(Gst.State.NULL)
, что является простым тест и использует только «раковина объект», или те, что поток пример файла GStreamer (Синтел Movie Trailer), как это:
#!/usr/bin/env python3
# -*- coding:utf-8 -*-
# GStreamer SDK Tutorials in Python
#
# basic-tutorial-4
#
"""
basic-tutorial-4: Time management
http://docs.gstreamer.com/display/GstSDK/Basic+tutorial+4%3A+Time+management
"""
import sys
from gi.repository import Gst
Gst.init(None)
# Python version of GST_TIME_ARGS
def convert_ns(t):
s, ns = divmod(t, 1000000000)
m, s = divmod(s, 60)
if m < 60:
return "0:%02i:%02i.%i" % (m, s, ns)
else:
h, m = divmod(m, 60)
return "%i:%02i:%02i.%i" % (h, m, s, ns)
def handle_message(data, msg):
if message.type == Gst.MessageType.ERROR:
err, debug = message.parse_error()
print("Error received from element %s: %s" % (message.src.get_name(), err), file=sys.stderr)
print("Debugging information: %s" % debug, file=sys.stderr)
data["terminate"] = True
elif message.type == Gst.MessageType.EOS:
print("End-Of-Stream reached.")
data["terminate"] = True
elif message.type == Gst.MessageType.DURATION_CHANGED:
# The duration has changed, mark the current one as invalid
data["duration"] = Gst.CLOCK_TIME_NONE
elif message.type == Gst.MessageType.STATE_CHANGED:
if message.src == data["playbin"]:
old_state, new_state, pending_state = message.parse_state_changed()
print("Pipeline state changed from %s to %s." % (old_state.value_nick, new_state.value_nick))
data["playing"] = (new_state == Gst.State.PLAYING)
if data["playing"]:
query = Gst.Query.new_seeking(Gst.Format.TIME)
if data["playbin"].query(query):
(aux, data["seek_enabled"], start, end) = query.parse_seeking()
if data["seek_enabled"]:
print("Seeking is ENABLED from %s to %s" % (convert_ns(start), convert_ns(end)))
else:
print("Seeking is DISABLED for this stream.")
else:
print("Seeking query failed.", file=sys.stderr)
else:
print("Unexpected message received.", file=sys.stderr)
data = dict()
data["playing"] = False
data["terminate"] = False
data["seek_enabled"] = False
data["seek_done"] = False
data["duration"] = Gst.CLOCK_TIME_NONE
# Create the elements
data["playbin"] = Gst.ElementFactory.make("playbin", "playbin")
if not data["playbin"]:
print("Not all elements could be created.", file=sys.stderr)
exit(-1)
# Set the URI to play
data["playbin"].set_property(
"uri", "http://docs.gstreamer.com/media/sintel_trailer-480p.webm")
# Start playing
ret = data["playbin"].set_state(Gst.State.PLAYING)
if ret == Gst.StateChangeReturn.FAILURE:
print("Unable to set the pipeline to the playing state.", file=sys.stderr)
exit(-1)
# Listen to the bus
bus = data["playbin"].get_bus()
while not data["terminate"]:
message = bus.timed_pop_filtered(100 * Gst.MSECOND,
Gst.MessageType.STATE_CHANGED |
Gst.MessageType.ERROR |
Gst.MessageType.EOS |
Gst.MessageType.DURATION_CHANGED)
# Parse message
if message:
handle_message(data, message)
else:
if data["playing"]:
fmt = Gst.Format.TIME
current = -1
# Query the current position of the stream
_, current = data['playbin'].query_position(fmt)
if not current:
print("Could not query current position", file=sys.stderr)
# If we didn't know it yet, query the stream duration
if data["duration"] == Gst.CLOCK_TIME_NONE:
_, data["duration"] = data['playbin'].query_duration(fmt)
if not data["duration"]:
print("Could not query current duration", file=sys.stderr)
print("Position %s/%s\r" % (
convert_ns(current), convert_ns(data["duration"])), end=' ')
sys.stdout.flush()
# If seeking is enabled, we have not done it yet, and the time is
# right, seek
if data["seek_enabled"] and not data["seek_done"] and current > 10 * Gst.SECOND:
print("\nReached 10s, performing seek...")
data['playbin'].seek_simple(Gst.Format.TIME, Gst.SeekFlags.FLUSH | Gst.SeekFlags.KEY_UNIT, 30 * Gst.SECOND)
data["seek_done"] = True
# Free resources
data["playbin"].set_state(Gst.State.NULL)
Так, после попытки изменить код у меня есть некоторые вопросы :
- Является ли этот файл «/// C: /folder/video.avi» правильным форматом пути для GStreamer?
- Я знаю, что мне нужно использовать объект «playerbin» и установить его свойство uri, но я не знаю, где именно я должен поместить эти строки и как правильно их использовать.
- Есть ли проблемы, вызванные видеоформатом?
Большое вам спасибо за помощь!