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142 lines
3.3 KiB
C
142 lines
3.3 KiB
C
/* GStreamer
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*
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* stepping.c: stepping sample application
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*
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* Copyright (C) 2009 Wim Taymans <wim.taymans@gmail.com>
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Library General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Library General Public License for more details.
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*
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* You should have received a copy of the GNU Library General Public
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* License along with this library; if not, write to the
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* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
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* Boston, MA 02110-1301, USA.
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*/
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#include <stdlib.h>
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#include <math.h>
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#include <gst/gst.h>
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static GMainLoop *loop;
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static gdouble period = 0.0;
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static void
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do_step (GstElement * bin)
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{
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gdouble rate;
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rate = sin (period);
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period += G_PI / 150;
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rate += 1.2;
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gst_element_send_event (bin,
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gst_event_new_step (GST_FORMAT_TIME, 40 * GST_MSECOND, rate, FALSE,
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FALSE));
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}
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static void
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handle_sync_message (GstBus * bus, GstMessage * message, gpointer data)
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{
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GstElement *bin;
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bin = GST_ELEMENT_CAST (data);
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switch (message->type) {
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case GST_MESSAGE_STEP_DONE:
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do_step (bin);
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break;
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default:
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break;
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}
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}
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static void
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handle_message (GstBus * bus, GstMessage * message, gpointer data)
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{
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switch (message->type) {
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case GST_MESSAGE_EOS:
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g_message ("got EOS");
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g_main_loop_quit (loop);
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break;
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case GST_MESSAGE_WARNING:
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case GST_MESSAGE_ERROR:
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{
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GError *gerror;
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gchar *debug;
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if (message->type == GST_MESSAGE_ERROR)
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gst_message_parse_error (message, &gerror, &debug);
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else
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gst_message_parse_warning (message, &gerror, &debug);
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gst_object_default_error (GST_MESSAGE_SRC (message), gerror, debug);
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g_error_free (gerror);
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g_free (debug);
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if (message->type == GST_MESSAGE_ERROR)
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g_main_loop_quit (loop);
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break;
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}
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default:
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break;
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}
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}
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int
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main (int argc, char *argv[])
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{
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GstElement *bin;
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GstBus *bus;
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gst_init (&argc, &argv);
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if (argc < 2) {
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g_print ("usage: %s <uri>\n", argv[0]);
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return -1;
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}
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/* create a new bin to hold the elements */
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bin = gst_element_factory_make ("playbin", "bin");
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g_assert (bin);
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g_object_set (bin, "uri", argv[1], NULL);
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bus = gst_pipeline_get_bus (GST_PIPELINE (bin));
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gst_bus_add_signal_watch (bus);
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gst_bus_enable_sync_message_emission (bus);
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g_signal_connect (bus, "message", (GCallback) handle_message, bin);
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g_signal_connect (bus, "sync-message", (GCallback) handle_sync_message, bin);
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/* go to the PAUSED state and wait for preroll */
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g_message ("prerolling first frame");
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gst_element_set_state (bin, GST_STATE_PAUSED);
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gst_element_get_state (bin, NULL, NULL, -1);
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/* queue step */
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do_step (bin);
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gst_element_set_state (bin, GST_STATE_PLAYING);
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loop = g_main_loop_new (NULL, TRUE);
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g_main_loop_run (loop);
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g_message ("finished");
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/* stop the bin */
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gst_element_set_state (bin, GST_STATE_NULL);
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g_main_loop_unref (loop);
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gst_object_unref (bus);
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exit (0);
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}
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