Question

我正在尝试用tkinter，GStreamer和python3制作视频播放器，我有以下代码

import sys, os
from tkinter import *
from gi.repository import GObject
from gi.repository import GLib
from gi.repository import Gtk
from gi.repository import Gst
def start():
        player.set_property('video-sink', None)
        player.set_property("uri", "./video.avi")
        player.set_state(Gst.STATE_PLAYING)

def on_sync_message(bus, message):
        if message.structure is None:
                return
        message_name = message.structure.get_name()
        if message_name == "prepare-xwindow-id":
                imagesink = message.src
                imagesink.set_property("force-aspect-ratio", True)
                imagesink.set_xwindow_id(mwin_id)

window = Tk()
window.geometry("500x400")
movie_window = Frame(window,bg='#000000')
movie_window.pack(side=BOTTOM,anchor=S,expand=YES,fill=BOTH)

mwin_id = movie_window.winfo_id()

player = Gst.ElementFactory.make("playbin2", "player")
fakesink = Gst.ElementFactory.make("fakesink", "fakesink")
player.set_property("video-sink", fakesink)


bus = player.get_bus()
bus.add_signal_watch()
bus.enable_sync_message_emission()
bus.connect("sync-message::element", on_sync_message)


window.mainloop()
start()

但收到错误：

(reproductor4.py:6856): GStreamer-CRITICAL **: gst_element_factory_make: assertion `gst_is_initialized ()' failed
Traceback (most recent call last):
  File "reproductor4.py", line 30, in <module>
    player.set_property("video-sink", fakesink)
AttributeError: 'NoneType' object has no attribute 'set_property'

为什么会发生这种情况的一些想法？

Answer 1

第30行是player.set_property("video-sink", fakesink)。回溯和属性错误消息似乎声称player为无。在该行之前使用print(player)进行测试。但是，我不明白Traceback之前的额外消息。它表明gst代码中的断言失败了。

Answer 2

您的问题实际上是：

(reproductor4.py:6856): GStreamer-CRITICAL **: gst_element_factory_make: assertion `gst_is_initialized ()' failed

您的代码中没有任何内容正在调用初始化例程：gst_init（）（它可能是python中的Gst.init（））。如果没有初始化，gstreamer将无法正常工作。

Answer 3

解决方案是这样的：最后在调用之前只附加这一行： GObject.threads_init（） Gst.init（无）

'NoneType'对象没有属性'set_property'Tkinter，GStreamer python3

3 个答案: