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#include <stdlib.h>
#include <gst/gst.h>
/* This example uses the queue element to create a buffer between 2 elements.
* The scheduler automatically uses 2 threads, 1 to feed and another to consume
* data from the queue buffer
*/
/* Event loop to listen to events posted on the GstBus from the pipeline. Exits
* on EOS or ERROR events
*/
static void
event_loop (GstElement * pipe)
{
GstBus *bus;
GstMessage *message = NULL;
gboolean running = TRUE;
bus = gst_element_get_bus (GST_ELEMENT (pipe));
while (running) {
message = gst_bus_poll (bus, GST_MESSAGE_ANY, -1);
g_assert (message != NULL);
switch (message->type) {
case GST_MESSAGE_EOS:
running = FALSE;
break;
case GST_MESSAGE_WARNING:{
GError *gerror;
gchar *debug;
gst_message_parse_warning (message, &gerror, &debug);
gst_object_default_error (GST_MESSAGE_SRC (message), gerror, debug);
g_error_free (gerror);
g_free (debug);
break;
}
case GST_MESSAGE_ERROR:{
GError *gerror;
gchar *debug;
gst_message_parse_error (message, &gerror, &debug);
gst_object_default_error (GST_MESSAGE_SRC (message), gerror, debug);
g_error_free (gerror);
g_free (debug);
running = FALSE;
break;
}
default:
break;
}
gst_message_unref (message);
}
gst_object_unref (bus);
}
int
main (int argc, char *argv[])
{
GstElement *filesrc, *audiosink, *decode, *queue;
GstElement *pipeline;
gst_init (&argc, &argv);
if (argc != 2) {
g_print ("usage: %s <filename>\n", argv[0]);
exit (-1);
}
/* create a new pipeline to hold the elements */
pipeline = gst_pipeline_new ("pipeline");
g_assert (pipeline != NULL);
/* create a disk reader */
filesrc = gst_element_factory_make ("filesrc", "disk_source");
g_assert (filesrc != NULL);
g_object_set (G_OBJECT (filesrc), "location", argv[1], NULL);
decode = gst_element_factory_make ("mad", "decode");
g_assert (decode != NULL);
queue = gst_element_factory_make ("queue", "queue");
g_assert (queue != NULL);
/* and an audio sink */
audiosink = gst_element_factory_make ("alsasink", "play_audio");
g_assert (audiosink != NULL);
/* add objects to the main pipeline */
gst_bin_add_many (GST_BIN (pipeline), filesrc, decode, queue, audiosink,
NULL);
gst_element_link_many (filesrc, decode, queue, audiosink, NULL);
/* start playing */
gst_element_set_state (GST_ELEMENT (pipeline), GST_STATE_PLAYING);
/* Listen for EOS */
event_loop (pipeline);
gst_element_set_state (GST_ELEMENT (pipeline), GST_STATE_NULL);
exit (0);
}
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