/* 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_new_step (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); }