tests/examples/dynamic/sprinkle2.c - mtk-gst-plugins-base-debian - Git at Google

 /* GStreamer
  *
  * sprinkle.c: sample application to dynamically mix tones with adder
  *
  * Copyright (C) <2009> 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.
  */

 /*
  * Produces a sweeping sprinkle of tones by dynamically adding and removing
  * elements to adder.
  *
  * gcc `pkg-config --cflags --libs gstreamer-0.10` sprinkle2.c -osprinkle2
  */

 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif

 #include <gst/gst.h>

 static GstElement *pipeline, *adder;
 static GMainLoop *loop;

 typedef struct
 {
   GstElement *src, *fx;
   GstPad *src_srcpad;
   GstPad *fx_sinkpad, *fx_srcpad;
   GstPad *adder_sinkpad;
   gdouble freq;
   gfloat pos;
 } SourceInfo;

 /* dynamically add the source to the pipeline and link it to a new pad on
  * adder */
 static SourceInfo *
 add_source (gdouble freq, gfloat pos)
 {
   SourceInfo *info;

   info = g_new0 (SourceInfo, 1);
   info->freq = freq;
   info->pos = pos;

   /* make source with unique name */
   info->src = gst_element_factory_make ("audiotestsrc", NULL);
   info->fx = gst_element_factory_make ("audiopanorama", NULL);

   g_object_set (info->src, "freq", freq, "volume", (gdouble) 0.35, NULL);
   g_object_set (info->fx, "panorama", pos, NULL);

   /* add to the bin */
   gst_bin_add (GST_BIN (pipeline), info->src);
   gst_bin_add (GST_BIN (pipeline), info->fx);

   /* get pads from the elements */
   info->src_srcpad = gst_element_get_static_pad (info->src, "src");
   info->fx_srcpad = gst_element_get_static_pad (info->fx, "src");
   info->fx_sinkpad = gst_element_get_static_pad (info->fx, "sink");

   /* get new pad from adder, adder will now wait for data on this pad */
   info->adder_sinkpad = gst_element_get_request_pad (adder, "sink_%u");

   /* link src to fx and fx to adder */
   gst_pad_link (info->fx_srcpad, info->adder_sinkpad);
   gst_pad_link (info->src_srcpad, info->fx_sinkpad);

   /* and play the elements, change the state from sink to source */
   gst_element_set_state (info->fx, GST_STATE_PLAYING);
   gst_element_set_state (info->src, GST_STATE_PLAYING);

   g_print ("added  freq %5.0f, pos %3.1f\n", info->freq, info->pos);

   return info;
 }

 /* remove the source from the pipeline after removing it from adder */
 static void
 remove_source (SourceInfo * info)
 {
   g_print ("remove freq %5.0f, pos %3.1f\n", info->freq, info->pos);

   /* lock the state so that we can put it to NULL without the parent messing
    * with our state */
   gst_element_set_locked_state (info->src, TRUE);
   gst_element_set_locked_state (info->fx, TRUE);

   /* first stop the source. Remember that this might block when in the PAUSED
    * state. Alternatively one could send EOS to the source, install an event
    * probe and schedule a state change/unlink/release from the mainthread. */
   gst_element_set_state (info->fx, GST_STATE_NULL);
   /* NOTE that the source emits EOS when shutting down but the EOS will not
    * reach the adder sinkpad because the effect is in the NULL state. We will
    * send an EOS to adder later. */
   gst_element_set_state (info->src, GST_STATE_NULL);

   /* unlink from adder */
   gst_pad_unlink (info->src_srcpad, info->fx_sinkpad);
   gst_pad_unlink (info->fx_srcpad, info->adder_sinkpad);
   gst_object_unref (info->src_srcpad);
   gst_object_unref (info->fx_srcpad);
   gst_object_unref (info->fx_sinkpad);

   /* remove from the bin */
   gst_bin_remove (GST_BIN (pipeline), info->src);
   gst_bin_remove (GST_BIN (pipeline), info->fx);

   /* send EOS to the sinkpad to make adder EOS when needed */
   gst_pad_send_event (info->adder_sinkpad, gst_event_new_eos ());

   /* give back the pad */
   gst_element_release_request_pad (adder, info->adder_sinkpad);
   gst_object_unref (info->adder_sinkpad);

   g_free (info);
 }

 /* we'll keep the state of the sources in this structure. We keep 3 sources
  * alive */
 typedef struct
 {
   guint count;
   SourceInfo *infos[3];
 } SprinkleState;

 static SprinkleState *
 create_state (void)
 {
   SprinkleState *state;

   state = g_new0 (SprinkleState, 1);

   return state;
 }

 static void
 free_state (SprinkleState * state)
 {
   SourceInfo *info;
   gint i;

   for (i = 0; i < 3; i++) {
     info = state->infos[i];
     if (info)
       remove_source (info);
   }

   g_free (state);
 }

 static gboolean
 do_sprinkle (SprinkleState * state)
 {
   SourceInfo *info;
   gint i;

   /* first remove the oldest info */
   info = state->infos[2];

   if (info)
     remove_source (info);

   /* move sources */
   for (i = 2; i > 0; i--) {
     state->infos[i] = state->infos[i - 1];
   }

   /* add new source, stop adding sources after 10 rounds. */
   if (state->count < 20) {
     state->infos[0] = add_source (
         (gdouble) ((state->count * 100) + 200),
         ((gfloat) (state->count % 5) / 2.0 - 1.0));
     state->count++;
   } else {
     state->infos[0] = NULL;
   }
   return TRUE;
 }

 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);
 }

 int
 main (int argc, char *argv[])
 {
   GstBus *bus;
   GstElement *filter, *convert, *sink;
   GstCaps *caps;
   gboolean res;
   SprinkleState *state;

   gst_init (&argc, &argv);

   loop = g_main_loop_new (NULL, TRUE);

   pipeline = gst_pipeline_new ("pipeline");

   /* add the fixed part to the pipeline. Remember that we need a capsfilter
    * after adder so that multiple sources are not racing to negotiate
    * a format */
   adder = gst_element_factory_make ("adder", "adder");
   filter = gst_element_factory_make ("capsfilter", "filter");
   convert = gst_element_factory_make ("audioconvert", "convert");
   sink = gst_element_factory_make ("autoaudiosink", "sink");

   caps = gst_caps_new_simple ("audio/x-raw",
       "format", G_TYPE_STRING, "S16LE",
       "channels", G_TYPE_INT, 2, "rate", G_TYPE_INT, 44100, NULL);
   g_object_set (filter, "caps", caps, NULL);
   gst_caps_unref (caps);

   gst_bin_add_many (GST_BIN (pipeline), adder, filter, convert, sink, NULL);

   res = gst_element_link_many (adder, filter, convert, sink, NULL);
   g_assert (res);

   /* 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, the pipeline will not yet preroll because
    * there is no source providing data for it yet */
   gst_element_set_state (pipeline, GST_STATE_PLAYING);

   /* and add the function that modifies the pipeline every 100ms */
   state = create_state ();
   g_timeout_add (100, (GSourceFunc) do_sprinkle, state);

   /* go to main loop */
   g_main_loop_run (loop);

   gst_element_set_state (pipeline, GST_STATE_NULL);

   free_state (state);
   gst_object_unref (bus);
   gst_object_unref (pipeline);

   return 0;
 }
	/* GStreamer
	*
	* sprinkle.c: sample application to dynamically mix tones with adder
	*
	* Copyright (C) <2009> 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.
	*/

	/*
	* Produces a sweeping sprinkle of tones by dynamically adding and removing
	* elements to adder.
	*
	* gcc `pkg-config --cflags --libs gstreamer-0.10` sprinkle2.c -osprinkle2
	*/

	#ifdef HAVE_CONFIG_H
	#include "config.h"
	#endif

	#include <gst/gst.h>

	static GstElement pipeline, adder;
	static GMainLoop *loop;

	typedef struct
	{
	GstElement src, fx;
	GstPad *src_srcpad;
	GstPad fx_sinkpad, fx_srcpad;
	GstPad *adder_sinkpad;
	gdouble freq;
	gfloat pos;
	} SourceInfo;

	/* dynamically add the source to the pipeline and link it to a new pad on
	* adder */
	static SourceInfo *
	add_source (gdouble freq, gfloat pos)
	{
	SourceInfo *info;

	info = g_new0 (SourceInfo, 1);
	info->freq = freq;
	info->pos = pos;

	/* make source with unique name */
	info->src = gst_element_factory_make ("audiotestsrc", NULL);
	info->fx = gst_element_factory_make ("audiopanorama", NULL);

	g_object_set (info->src, "freq", freq, "volume", (gdouble) 0.35, NULL);
	g_object_set (info->fx, "panorama", pos, NULL);

	/* add to the bin */
	gst_bin_add (GST_BIN (pipeline), info->src);
	gst_bin_add (GST_BIN (pipeline), info->fx);

	/* get pads from the elements */
	info->src_srcpad = gst_element_get_static_pad (info->src, "src");
	info->fx_srcpad = gst_element_get_static_pad (info->fx, "src");
	info->fx_sinkpad = gst_element_get_static_pad (info->fx, "sink");

	/* get new pad from adder, adder will now wait for data on this pad */
	info->adder_sinkpad = gst_element_get_request_pad (adder, "sink_%u");

	/* link src to fx and fx to adder */
	gst_pad_link (info->fx_srcpad, info->adder_sinkpad);
	gst_pad_link (info->src_srcpad, info->fx_sinkpad);

	/* and play the elements, change the state from sink to source */
	gst_element_set_state (info->fx, GST_STATE_PLAYING);
	gst_element_set_state (info->src, GST_STATE_PLAYING);

	g_print ("added freq %5.0f, pos %3.1f\n", info->freq, info->pos);

	return info;
	}

	/* remove the source from the pipeline after removing it from adder */
	static void
	remove_source (SourceInfo * info)
	{
	g_print ("remove freq %5.0f, pos %3.1f\n", info->freq, info->pos);

	/* lock the state so that we can put it to NULL without the parent messing
	* with our state */
	gst_element_set_locked_state (info->src, TRUE);
	gst_element_set_locked_state (info->fx, TRUE);

	/* first stop the source. Remember that this might block when in the PAUSED
	* state. Alternatively one could send EOS to the source, install an event
	* probe and schedule a state change/unlink/release from the mainthread. */
	gst_element_set_state (info->fx, GST_STATE_NULL);
	/* NOTE that the source emits EOS when shutting down but the EOS will not
	* reach the adder sinkpad because the effect is in the NULL state. We will
	* send an EOS to adder later. */
	gst_element_set_state (info->src, GST_STATE_NULL);

	/* unlink from adder */
	gst_pad_unlink (info->src_srcpad, info->fx_sinkpad);
	gst_pad_unlink (info->fx_srcpad, info->adder_sinkpad);
	gst_object_unref (info->src_srcpad);
	gst_object_unref (info->fx_srcpad);
	gst_object_unref (info->fx_sinkpad);

	/* remove from the bin */
	gst_bin_remove (GST_BIN (pipeline), info->src);
	gst_bin_remove (GST_BIN (pipeline), info->fx);

	/* send EOS to the sinkpad to make adder EOS when needed */
	gst_pad_send_event (info->adder_sinkpad, gst_event_new_eos ());

	/* give back the pad */
	gst_element_release_request_pad (adder, info->adder_sinkpad);
	gst_object_unref (info->adder_sinkpad);

	g_free (info);
	}

	/* we'll keep the state of the sources in this structure. We keep 3 sources
	* alive */
	typedef struct
	{
	guint count;
	SourceInfo *infos[3];
	} SprinkleState;

	static SprinkleState *
	create_state (void)
	{
	SprinkleState *state;

	state = g_new0 (SprinkleState, 1);

	return state;
	}

	static void
	free_state (SprinkleState * state)
	{
	SourceInfo *info;
	gint i;

	for (i = 0; i < 3; i++) {
	info = state->infos[i];
	if (info)
	remove_source (info);
	}

	g_free (state);
	}

	static gboolean
	do_sprinkle (SprinkleState * state)
	{
	SourceInfo *info;
	gint i;

	/* first remove the oldest info */
	info = state->infos[2];

	if (info)
	remove_source (info);

	/* move sources */
	for (i = 2; i > 0; i--) {
	state->infos[i] = state->infos[i - 1];
	}

	/* add new source, stop adding sources after 10 rounds. */
	if (state->count < 20) {
	state->infos[0] = add_source (
	(gdouble) ((state->count * 100) + 200),
	((gfloat) (state->count % 5) / 2.0 - 1.0));
	state->count++;
	} else {
	state->infos[0] = NULL;
	}
	return TRUE;
	}

	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);
	}

	int
	main (int argc, char *argv[])
	{
	GstBus *bus;
	GstElement filter, convert, *sink;
	GstCaps *caps;
	gboolean res;
	SprinkleState *state;

	gst_init (&argc, &argv);

	loop = g_main_loop_new (NULL, TRUE);

	pipeline = gst_pipeline_new ("pipeline");

	/* add the fixed part to the pipeline. Remember that we need a capsfilter
	* after adder so that multiple sources are not racing to negotiate
	* a format */
	adder = gst_element_factory_make ("adder", "adder");
	filter = gst_element_factory_make ("capsfilter", "filter");
	convert = gst_element_factory_make ("audioconvert", "convert");
	sink = gst_element_factory_make ("autoaudiosink", "sink");

	caps = gst_caps_new_simple ("audio/x-raw",
	"format", G_TYPE_STRING, "S16LE",
	"channels", G_TYPE_INT, 2, "rate", G_TYPE_INT, 44100, NULL);
	g_object_set (filter, "caps", caps, NULL);
	gst_caps_unref (caps);

	gst_bin_add_many (GST_BIN (pipeline), adder, filter, convert, sink, NULL);

	res = gst_element_link_many (adder, filter, convert, sink, NULL);
	g_assert (res);

	/* 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, the pipeline will not yet preroll because
	* there is no source providing data for it yet */
	gst_element_set_state (pipeline, GST_STATE_PLAYING);

	/* and add the function that modifies the pipeline every 100ms */
	state = create_state ();
	g_timeout_add (100, (GSourceFunc) do_sprinkle, state);

	/* go to main loop */
	g_main_loop_run (loop);

	gst_element_set_state (pipeline, GST_STATE_NULL);

	free_state (state);
	gst_object_unref (bus);
	gst_object_unref (pipeline);

	return 0;
	}