| /* GStreamer |
| * |
| * addstream.c: sample application to dynamically add streams to a running |
| * pipeline |
| * |
| * Copyright (C) <2007> Wim Taymans <wim dot taymans at gmail dot 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., 51 Franklin St, Fifth Floor, |
| * Boston, MA 02110-1301, USA. |
| */ |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #include <gst/gst.h> |
| |
| static GstElement *pipeline; |
| static GstClock *theclock; |
| static GMainLoop *loop; |
| static GstElement *bin1, *bin2, *bin3, *bin4, *bin5; |
| |
| /* start a bin with the given description */ |
| static GstElement * |
| create_stream (const gchar * descr) |
| { |
| GstElement *bin; |
| GError *error = NULL; |
| |
| bin = gst_parse_launch (descr, &error); |
| if (error) { |
| g_print ("pipeline could not be constructed: %s\n", error->message); |
| g_error_free (error); |
| return NULL; |
| } |
| |
| /* add the bin to the pipeline now, this will set the current base_time of the |
| * pipeline on the new bin. */ |
| gst_bin_add (GST_BIN_CAST (pipeline), bin); |
| |
| return bin; |
| } |
| |
| static void |
| pause_play_stream (GstElement * bin, gint seconds) |
| { |
| gboolean punch_in; |
| GstStateChangeReturn ret; |
| GstClockTime now, base_time, running_time; |
| |
| /* get current running time, we need this value to continue playback of |
| * non-live pipelines. */ |
| now = gst_clock_get_time (theclock); |
| base_time = gst_element_get_base_time (bin); |
| |
| running_time = now - base_time; |
| |
| /* set the new bin to PAUSED, the parent bin will notice (because of the ASYNC |
| * message and will perform latency calculations again when going to PLAYING |
| * later. */ |
| ret = gst_element_set_state (bin, GST_STATE_PAUSED); |
| |
| switch (ret) { |
| case GST_STATE_CHANGE_NO_PREROLL: |
| /* live source, timestamps are running_time of the pipeline clock. */ |
| punch_in = FALSE; |
| break; |
| case GST_STATE_CHANGE_SUCCESS: |
| /* success, no async state changes, same as async, timestamps start |
| * from 0 */ |
| case GST_STATE_CHANGE_ASYNC: |
| /* no live source, bin will preroll. We have to punch it in because in |
| * this situation timestamps start from 0. */ |
| punch_in = TRUE; |
| break; |
| case GST_STATE_CHANGE_FAILURE: |
| /* fall through to return */ |
| default: |
| return; |
| } |
| |
| if (seconds) |
| g_usleep (seconds * G_USEC_PER_SEC); |
| |
| if (punch_in) { |
| /* new bin has to be aligned with previous running_time. We do this by taking |
| * the current absolute clock time and calculating the base time that would |
| * give the previous running_time. We set this base_time on the bin before |
| * setting it to PLAYING. */ |
| now = gst_clock_get_time (theclock); |
| base_time = now - running_time; |
| |
| gst_element_set_base_time (bin, base_time); |
| } |
| |
| /* now set the pipeline to PLAYING */ |
| gst_element_set_state (bin, GST_STATE_PLAYING); |
| } |
| |
| static void |
| message_received (GstBus * bus, GstMessage * message, GstPipeline * pipeline) |
| { |
| const GstStructure *s; |
| |
| s = gst_message_get_structure (message); |
| g_print ("message from \"%s\" (%s): ", |
| GST_STR_NULL (GST_ELEMENT_NAME (GST_MESSAGE_SRC (message))), |
| gst_message_type_get_name (GST_MESSAGE_TYPE (message))); |
| if (s) { |
| gchar *sstr; |
| |
| sstr = gst_structure_to_string (s); |
| g_print ("%s\n", sstr); |
| g_free (sstr); |
| } else { |
| g_print ("no message details\n"); |
| } |
| } |
| |
| static void |
| eos_message_received (GstBus * bus, GstMessage * message, |
| GstPipeline * pipeline) |
| { |
| message_received (bus, message, pipeline); |
| g_main_loop_quit (loop); |
| } |
| |
| static gboolean |
| perform_step (gpointer pstep) |
| { |
| gint step = GPOINTER_TO_INT (pstep); |
| |
| switch (step) { |
| case 0: |
| /* live stream locks on to running_time, pipeline configures latency. */ |
| g_print ("creating bin1\n"); |
| bin1 = |
| create_stream |
| ("( v4l2src ! videoconvert ! timeoverlay ! queue ! xvimagesink name=v4llive )"); |
| pause_play_stream (bin1, 0); |
| g_timeout_add_seconds (1, (GSourceFunc) perform_step, |
| GINT_TO_POINTER (1)); |
| break; |
| case 1: |
| /* live stream locks on to running_time, pipeline reconfigures latency |
| * together with the previously added bin so that they run synchronized. */ |
| g_print ("creating bin2\n"); |
| bin2 = create_stream ("( alsasrc ! queue ! alsasink name=alsalive )"); |
| pause_play_stream (bin2, 0); |
| g_timeout_add_seconds (1, (GSourceFunc) perform_step, |
| GINT_TO_POINTER (2)); |
| break; |
| case 2: |
| /* non-live stream, need base_time to align with current running live sources. */ |
| g_print ("creating bin3\n"); |
| bin3 = create_stream ("( audiotestsrc ! alsasink name=atnonlive )"); |
| pause_play_stream (bin3, 0); |
| g_timeout_add_seconds (1, (GSourceFunc) perform_step, |
| GINT_TO_POINTER (3)); |
| break; |
| case 3: |
| g_print ("creating bin4\n"); |
| bin4 = |
| create_stream |
| ("( videotestsrc ! timeoverlay ! videoconvert ! ximagesink name=vtnonlive )"); |
| pause_play_stream (bin4, 0); |
| g_timeout_add_seconds (1, (GSourceFunc) perform_step, |
| GINT_TO_POINTER (4)); |
| break; |
| case 4: |
| /* live stream locks on to running_time */ |
| g_print ("creating bin5\n"); |
| bin5 = |
| create_stream |
| ("( videotestsrc is-live=1 ! timeoverlay ! videoconvert ! ximagesink name=vtlive )"); |
| pause_play_stream (bin5, 0); |
| g_timeout_add_seconds (1, (GSourceFunc) perform_step, |
| GINT_TO_POINTER (5)); |
| break; |
| case 5: |
| /* pause the fist live stream for 2 seconds */ |
| g_print ("PAUSE bin1 for 2 seconds\n"); |
| pause_play_stream (bin1, 2); |
| /* pause the non-live stream for 2 seconds */ |
| g_print ("PAUSE bin4 for 2 seconds\n"); |
| pause_play_stream (bin4, 2); |
| /* pause the pseudo live stream for 2 seconds */ |
| g_print ("PAUSE bin5 for 2 seconds\n"); |
| pause_play_stream (bin5, 2); |
| g_print ("Waiting 5 seconds\n"); |
| g_timeout_add_seconds (5, (GSourceFunc) perform_step, |
| GINT_TO_POINTER (6)); |
| break; |
| case 6: |
| g_print ("quiting\n"); |
| g_main_loop_quit (loop); |
| break; |
| default: |
| break; |
| } |
| return FALSE; |
| } |
| |
| int |
| main (int argc, char *argv[]) |
| { |
| GstBus *bus; |
| |
| gst_init (&argc, &argv); |
| |
| loop = g_main_loop_new (NULL, TRUE); |
| |
| pipeline = gst_pipeline_new ("pipeline"); |
| |
| /* setup message handling */ |
| bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline)); |
| gst_bus_add_signal_watch_full (bus, G_PRIORITY_HIGH); |
| g_signal_connect (bus, "message::error", (GCallback) message_received, |
| pipeline); |
| g_signal_connect (bus, "message::warning", (GCallback) message_received, |
| pipeline); |
| g_signal_connect (bus, "message::eos", (GCallback) eos_message_received, |
| pipeline); |
| |
| /* we set the pipeline to PLAYING, this will distribute a default clock and |
| * start running. no preroll is needed */ |
| gst_element_set_state (pipeline, GST_STATE_PLAYING); |
| |
| /* get the clock now. Since we never set the pipeline to PAUSED again, the |
| * clock will not change, even when we add new clock providers later. */ |
| theclock = gst_element_get_clock (pipeline); |
| |
| /* start our actions while we are in the mainloop so that we can catch errors |
| * and other messages. */ |
| g_idle_add ((GSourceFunc) perform_step, GINT_TO_POINTER (0)); |
| /* go to main loop */ |
| g_main_loop_run (loop); |
| |
| gst_element_set_state (pipeline, GST_STATE_NULL); |
| |
| gst_object_unref (bus); |
| gst_object_unref (pipeline); |
| gst_object_unref (theclock); |
| |
| return 0; |
| } |