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/* GStreamer
* Copyright (C) 2006 Stefan Kost <ensonic@users.sf.net>
* Copyright (C) 2008 Jan Schmidt <jan.schmidt@sun.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 <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <gst/gst.h>
static guint spect_bands = 20;
#define AUDIOFREQ 32000
/* receive spectral data from element message */
gboolean
message_handler (GstBus * bus, GstMessage * message, gpointer data)
{
if (message->type == GST_MESSAGE_ELEMENT) {
const GstStructure *s = gst_message_get_structure (message);
const gchar *name = gst_structure_get_name (s);
GstClockTime endtime;
if (strcmp (name, "spectrum") == 0) {
const GValue *magnitudes;
const GValue *phases;
const GValue *mag, *phase;
gdouble freq;
guint i;
if (!gst_structure_get_clock_time (s, "endtime", &endtime))
endtime = GST_CLOCK_TIME_NONE;
g_print ("New spectrum message, endtime %" GST_TIME_FORMAT "\n",
GST_TIME_ARGS (endtime));
magnitudes = gst_structure_get_value (s, "magnitude");
phases = gst_structure_get_value (s, "phase");
for (i = 0; i < spect_bands; ++i) {
freq = (gdouble) ((AUDIOFREQ / 2) * i + AUDIOFREQ / 4) / spect_bands;
mag = gst_value_list_get_value (magnitudes, i);
phase = gst_value_list_get_value (phases, i);
if (mag != NULL && phase != NULL) {
g_print ("band %d (freq %g): magnitude %f dB phase %f\n", i, freq,
g_value_get_float (mag), g_value_get_float (phase));
}
}
g_print ("\n");
}
}
return TRUE;
}
int
main (int argc, char *argv[])
{
GstElement *bin;
GstElement *src, *audioconvert, *spectrum, *sink;
GstBus *bus;
GstCaps *caps;
GMainLoop *loop;
gst_init (&argc, &argv);
bin = gst_pipeline_new ("bin");
src = gst_element_factory_make ("audiotestsrc", "src");
g_object_set (G_OBJECT (src), "wave", 0, "freq", 6000.0, NULL);
audioconvert = gst_element_factory_make ("audioconvert", NULL);
g_assert (audioconvert);
spectrum = gst_element_factory_make ("spectrum", "spectrum");
g_object_set (G_OBJECT (spectrum), "bands", spect_bands, "threshold", -80,
"message", TRUE, "message-phase", TRUE, NULL);
sink = gst_element_factory_make ("fakesink", "sink");
g_object_set (G_OBJECT (sink), "sync", TRUE, NULL);
gst_bin_add_many (GST_BIN (bin), src, audioconvert, spectrum, sink, NULL);
caps = gst_caps_new_simple ("audio/x-raw-int",
"rate", G_TYPE_INT, AUDIOFREQ, NULL);
if (!gst_element_link (src, audioconvert) ||
!gst_element_link_filtered (audioconvert, spectrum, caps) ||
!gst_element_link (spectrum, sink)) {
fprintf (stderr, "can't link elements\n");
exit (1);
}
gst_caps_unref (caps);
bus = gst_element_get_bus (bin);
gst_bus_add_watch (bus, message_handler, NULL);
gst_object_unref (bus);
gst_element_set_state (bin, GST_STATE_PLAYING);
/* we need to run a GLib main loop to get the messages */
loop = g_main_loop_new (NULL, FALSE);
g_main_loop_run (loop);
gst_element_set_state (bin, GST_STATE_NULL);
gst_object_unref (bin);
return 0;
}
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