/* 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/*
* Produces a sweeping sprinkle of tones by dynamically adding and removing
* elements to adder.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/gst.h>
static GstElement *pipeline, *adder;
static GMainLoop *loop;
typedef struct
{
GstElement *element;
GstPad *srcpad;
GstPad *sinkpad;
} SourceInfo;
/* dynamically add the source to the pipeline and link it to a new pad on
* adder */
static SourceInfo *
add_source (char *file_location)
{
GstElement *audio_decoder, *convert1;
SourceInfo *info;
info = g_new0 (SourceInfo, 1);
/* make source with unique name */
info->element = gst_element_factory_make ("filesrc", "filesrc1");
g_object_set (info->element, "location", file_location, NULL);
audio_decoder = gst_element_factory_make ("mad", "mad2");
convert1 = gst_element_factory_make ("audioconvert", "convert1");
/* add to the bin */
gst_bin_add_many (GST_BIN (pipeline), info->element, audio_decoder, convert1, NULL);
gst_element_link_many (info->element, audio_decoder, convert1, NULL);
/* get pad from the element */
info->srcpad = gst_element_get_static_pad (convert1, "src");
/* get new pad from adder, adder will now wait for data on this pad */
info->sinkpad = gst_element_get_request_pad (adder, "sink%d");
/* link pad to adder */
gst_pad_link (info->srcpad, info->sinkpad);
/* and play the element */
gst_element_set_state (info->element, GST_STATE_PLAYING);
return info;
}
/* remove the source from the pipeline after removing it from adder */
static void
remove_source (SourceInfo * info)
{
/* lock the state so that we can put it to NULL without the parent messing
* with our state */
gst_element_set_locked_state (info->element, 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.
* Note that changing the state of a source makes it emit an EOS, which can
* make adder go EOS. */
gst_element_set_state (info->element, GST_STATE_NULL);
/* unlink from adder */
gst_pad_unlink (info->srcpad, info->sinkpad);
gst_object_unref (info->srcpad);
/* remove from the bin */
gst_bin_remove (GST_BIN (pipeline), info->element);
/* give back the pad */
gst_element_release_request_pad (adder, info->sinkpad);
gst_object_unref (info->sinkpad);
g_free (info);
}
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, *convert1, *sink, *src1, *audio_decoder;
GstCaps *caps;
GstPad *srcpad;
GstPad *sinkpad;
gboolean res;
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 ("pulsesink", "sink");
g_object_set (G_OBJECT(sink), "sync", FALSE, NULL);
caps = gst_caps_new_simple ("audio/x-raw-int",
"endianness", G_TYPE_INT, G_LITTLE_ENDIAN,
"channels", G_TYPE_INT, 1,
"width", G_TYPE_INT, 16,
"depth", G_TYPE_INT, 16,
"rate", G_TYPE_INT, 44100, "signed", G_TYPE_BOOLEAN, TRUE, NULL);
g_object_set (filter, "caps", caps, NULL);
gst_caps_unref (caps);
src1 = gst_element_factory_make ("filesrc", "filesrc0");
g_object_set (src1, "location", argv[1], NULL);
audio_decoder = gst_element_factory_make ("mad", "mad");
convert1 = gst_element_factory_make ("audioconvert", "convert2");
gst_bin_add_many (GST_BIN (pipeline), adder, filter, convert, sink, src1, audio_decoder, convert1, NULL);
res = gst_element_link (src1, audio_decoder);
g_assert (res);
res = gst_element_link (audio_decoder, convert1);
g_assert (res);
/*
res = gst_element_link (src1, convert1);
g_assert (res);
*/
res = gst_element_link_many (adder, filter, convert, sink, NULL);
g_assert (res);
/* get pad from the element */
srcpad = gst_element_get_static_pad (convert1, "src");
/* get new pad from adder, adder will now wait for data on this pad */
sinkpad = gst_element_get_request_pad (adder, "sink%d");
/* link pad to adder */
gst_pad_link (srcpad, sinkpad);
/* 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);
sleep (10);
add_source (argv[2]);
/* 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);
return 0;
}