GStreamer演示在虚拟机中不起作用(寻找简单的例子)

Question

我正试图编写一个非常简单的GStreamer应用程序。它做什么并不重要，只要GStreamer做一些事情。即使只是显示一些文本或简单的JPEG也可以。

下面是我可以通过谷歌找到的最好的例子(我添加了一些错误检查)。当我在Windows下运行的Linux虚拟机中运行它时，我看到这个控制台消息:

libEGL警告:pci id for fd 4: 80ee:beef, driver (null)

libEGL警告:DRI2:未能打开vboxvideo(搜索路径)/usr/lib/i386-linux-gnu/dri: ${起源}/dri:/usr/lib/dri)

google显示这是虚拟机内3D渲染的错误。我找不到解决办法。

那么，有人能修复下面的代码，使其在VM中运行吗?我想这意味着要避免3D渲染，所以可能会显示图像或一些文本?没有必要播放视频，这只是一个简单的概念证明，使用GStreamer在其他东西(必须在虚拟机中运行)。

下面是代码…

void GstreamerPlayVideo()
{
      GstElement *pipeline;
      GstBus *bus;
      GstMessage *msg;
      int argc;
      GError *error = NULL;
      /* Initialize GStreamer */
      if (gst_init_check(&argc, NULL, &error) == TRUE)
      {
          /* Build the pipeline */
          // Change URL to test failure
          pipeline = gst_parse_launch ("bin uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", &error);
////          pipeline = gst_parse_launch ("bin uri=http://tecfa.unige.ch/guides/x3d/www.web3d.org/x3d/content/examples/HelloWorld.gif", &error);
          if (pipeline != NULL)
          {
              /* Start playing */
              gst_element_set_state (pipeline, GST_STATE_PLAYING);
              /* wait until it's up and running or failed */
              if (gst_element_get_state (pipeline, NULL, NULL, -1) == GST_STATE_CHANGE_FAILURE)
              {
                 g_error ("GST failed to go into PLAYING state");
                 exit(1);
              }
              /* Wait until error or EOS */
              bus = gst_element_get_bus (pipeline);
              if (bus != NULL)
              {
                  msg = gst_bus_timed_pop_filtered (bus, GST_CLOCK_TIME_NONE, GST_MESSAGE_ERROR | GST_MESSAGE_EOS);
                  /* Parse message */
                  if (msg != NULL)
                  {
                    gchar *debug_info;
                    switch (GST_MESSAGE_TYPE (msg))
                    {
                      case GST_MESSAGE_ERROR:
                        gst_message_parse_error (msg, &error, &debug_info);
                        g_printerr ("Error received from element %s: %sn", GST_OBJECT_NAME (msg->src), error->message);
                        g_printerr ("Debugging information: %sn", debug_info ? debug_info : "none");
                        g_clear_error (&error);
                        g_free (debug_info);
                        break;
                      case GST_MESSAGE_EOS:
                        g_print ("End-Of-Stream reached.n");
                        break;
                      default:
                        /* We should not reach here because we only asked for ERRORs and EOS */
                        g_printerr ("Unexpected message received.n");
                        break;
                    }
                    gst_message_unref (msg);
                  }
                  /* Free resources */
                  gst_object_unref (bus);
                  gst_element_set_state (pipeline, GST_STATE_NULL);
                  gst_object_unref (pipeline);
              }
              else
              {
                    g_print ("GST get bus error: %sn", error->message);
                    exit(1);
              }
          }
          else
          {
                g_print ("GST parse error: %sn", error->message);
                exit(1);
          }
      }
      else
      {
            g_print ("GST init error: %sn", error->message);
            exit(1);
      }
}   // GstreamerPlayVideo()

Answer 1

尝试在管道中手动指定视频接收器。

videotestsrc !ximagesink

您的系统可能安装了EGL视频接收器插件作为主要视频插件。Ximagesink似乎更有可能工作。

:

//this line is where you're creating your pipeline
pipeline = gst_parse_launch ("videotestsrc ! ximagesink", &error);

我建议先尝试gst-launch命令，这样你就可以掌握管道语法，接收器和源是什么，等等。您可以从命令行运行的最简单的测试是这样的(如果安装了gstreamer 1.0，则可能安装了0.10):

gst-launch-1.0 videotestsrc ! autovideosink