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/* GStreamer
*
* stepping.c: stepping sample application
*
* Copyright (C) 2009 Wim Taymans <wim.taymans@gmail.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include <stdlib.h>
#include <math.h>
#include <gst/gst.h>
static GMainLoop *loop;
static gdouble period = 0.0;
static void
do_step (GstElement * bin)
{
gdouble rate;
rate = sin (period);
period += M_PI / 150;
rate += 1.2;
gst_element_send_event (bin,
gst_event_step_new (GST_FORMAT_TIME, 40 * GST_MSECOND, rate, FALSE,
FALSE));
}
static void
handle_sync_message (GstBus * bus, GstMessage * message, gpointer data)
{
GstElement *bin;
bin = GST_ELEMENT_CAST (data);
switch (message->type) {
case GST_MESSAGE_STEP_DONE:
do_step (bin);
break;
default:
break;
}
}
static void
handle_message (GstBus * bus, GstMessage * message, gpointer data)
{
switch (message->type) {
case GST_MESSAGE_EOS:
g_message ("got EOS");
g_main_loop_quit (loop);
break;
case GST_MESSAGE_WARNING:
case GST_MESSAGE_ERROR:
{
GError *gerror;
gchar *debug;
if (message->type == GST_MESSAGE_ERROR)
gst_message_parse_error (message, &gerror, &debug);
else
gst_message_parse_warning (message, &gerror, &debug);
gst_object_default_error (GST_MESSAGE_SRC (message), gerror, debug);
g_error_free (gerror);
g_free (debug);
if (message->type == GST_MESSAGE_ERROR)
g_main_loop_quit (loop);
break;
}
default:
break;
}
}
int
main (int argc, char *argv[])
{
GstElement *bin;
GstBus *bus;
gst_init (&argc, &argv);
if (argc < 2) {
g_print ("usage: %s <uri>\n", argv[0]);
return -1;
}
/* create a new bin to hold the elements */
bin = gst_element_factory_make ("playbin2", "bin");
g_assert (bin);
g_object_set (bin, "uri", argv[1], NULL);
bus = gst_pipeline_get_bus (GST_PIPELINE (bin));
gst_bus_add_signal_watch (bus);
gst_bus_enable_sync_message_emission (bus);
g_signal_connect (bus, "message", (GCallback) handle_message, bin);
g_signal_connect (bus, "sync-message", (GCallback) handle_sync_message, bin);
/* go to the PAUSED state and wait for preroll */
g_message ("prerolling first frame");
gst_element_set_state (bin, GST_STATE_PAUSED);
gst_element_get_state (bin, NULL, NULL, -1);
/* queue step */
do_step (bin);
gst_element_set_state (bin, GST_STATE_PLAYING);
loop = g_main_loop_new (NULL, TRUE);
g_main_loop_run (loop);
g_message ("finished");
/* stop the bin */
gst_element_set_state (bin, GST_STATE_NULL);
g_main_loop_unref (loop);
gst_object_unref (bus);
exit (0);
}
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