Gstreamer 进程在 OSX 上以 Hello World 示例完成，退出代码为 132

Question

当我为 Gstreamers python API 运行 Hello World tutorial 时，我收到以下错误：

GST_DEBUG=3 python tutorial_1.py
0:00:01.787091000 98337 0x7fde78071920 ERROR              gldisplay gstgldisplay_cocoa.m:171:gst_gl_display_cocoa_setup_nsapp: Custom NSApp initialization failed
0:00:01.787178000 98337 0x7fde78071920 ERROR                glutils gstglutils.c:229:gst_gl_element_propagate_display_context:<sink> Could not get GL display connection
0:00:01.788032000 98337 0x7fde78071920 WARN                 playbin gstplaybin2.c:4757:autoplug_select_cb:<playbin0> Could not activate sink glimagesink
0:00:01.792032000 98337 0x7fde78071920 FIXME           videodecoder gstvideodecoder.c:1052:gst_video_decoder_drain_out:<vp8dec0> Sub-class should implement drain()
0:00:01.859639000 98337 0x7fde78071980 FIXME           videodecoder gstvideodecoder.c:1052:gst_video_decoder_drain_out:<vp8dec0> Sub-class should implement drain()
zsh: illegal hardware instruction  GST_DEBUG=3 python tutorial_1.py

但是当我在终端中运行 Gstreamer 命令时，该命令的目的基本相同，窗口会正确打开，没有任何问题：

gst-launch-1.0 -v playbin uri=https://www.freedesktop.org/software/gstreamer-sdk/data/media/sintel_trailer-480p.webm

寻找解决方案或推动正确的方向来解决这个问题。

环境：

• 硬件：
  • 型号名称：MacBook Pro
  • 型号标识符：MacBookPro13,3
  • 处理器名称：四核 Intel Core i7
  • 处理器速度：2.7 GHz
• 操作系统：
  • 系统版本：macOS 11.6 (20G165)
  • 内核版本：Darwin 20.6.0
• GStreamer 1.18.4
• pygobject 3.42.0
• python 3.9.7

教程中的代码：

#!/usr/bin/env python3
import sys

import gi

gi.require_version('GLib', '2.0')
gi.require_version('GObject', '2.0')
gi.require_version('Gst', '1.0')

from gi.repository import Gst, GObject, GLib

pipeline = None
bus = None
message = None

# initialize GStreamer
Gst.init(sys.argv[1:])

# build the pipeline
pipeline = Gst.parse_launch(
    "playbin uri=https://www.freedesktop.org/software/gstreamer-sdk/data/media/sintel_trailer-480p.webm"
)

# start playing
pipeline.set_state(Gst.State.PLAYING)

# wait until EOS or error
bus = pipeline.get_bus()
msg = bus.timed_pop_filtered(
    Gst.CLOCK_TIME_NONE,
    Gst.MessageType.ERROR | Gst.MessageType.EOS
)

# free resources
pipeline.set_state(Gst.State.NULL)

Answer 1

这可能是由于与 MacOS 上的 OpenGL 相关的一些要求。请注意，在您的示例中，playbin 将尝试打开一些 OpenGL 窗口以显示其中的视频。如需更多信息，请访问this 链接。

以下是一个简单的示例，如何使用 hello world 应用程序在 C++ 中解决该问题：

#include <gst/gst.h>

#include <thread>

#include <CoreFoundation/CoreFoundation.h>

int
main (int argc, char *argv[])
{
  std::thread t([&]{
    GstElement *pipeline;
    GstBus *bus;
    GstMessage *msg;

    /* Initialize GStreamer */
    gst_init(&argc, &argv);

    /* Build the pipeline */
    pipeline =
      gst_parse_launch
      ("playbin uri=https://www.freedesktop.org/software/gstreamer-sdk/data/media/sintel_trailer-480p.webm",
      NULL);

    /* Start playing */
    gst_element_set_state(pipeline, GST_STATE_PLAYING);

    /* Wait until error or EOS */
    bus = gst_element_get_bus(pipeline);
    msg = gst_bus_timed_pop_filtered(
        bus, GST_CLOCK_TIME_NONE,
        static_cast<GstMessageType>(GST_MESSAGE_ERROR | GST_MESSAGE_EOS));

    /* Free resources */
    if (msg != NULL)
      gst_message_unref(msg);
    gst_object_unref(bus);
    gst_element_set_state(pipeline, GST_STATE_NULL);
    gst_object_unref(pipeline);
  });
  CFRunLoopRun();
  t.join();
  return 0;
}

构建和运行：

$ clang++ -std=c++17  -ggdb -O0  gst.cpp $(pkg-config --cflags --libs gstreamer-1.0) -framework CoreFoundation
$ ./a.out