1 /* GStreamer
2 * Copyright (C) 2006 Stefan Kost <ensonic@users.sf.net>
3 * Copyright (C) 2008 Jan Schmidt <jan.schmidt@sun.com>
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
14 *
15 * You should have received a copy of the GNU Library General Public
16 * License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
18 * Boston, MA 02110-1301, USA.
19 */
20
21 #include <stdio.h>
22 #include <string.h>
23 #include <stdlib.h>
24 #include <gst/gst.h>
25
26 static guint spect_bands = 20;
27
28 #define AUDIOFREQ 32000
29
30 /* receive spectral data from element message */
31 static gboolean
message_handler(GstBus * bus,GstMessage * message,gpointer data)32 message_handler (GstBus * bus, GstMessage * message, gpointer data)
33 {
34 if (message->type == GST_MESSAGE_ELEMENT) {
35 const GstStructure *s = gst_message_get_structure (message);
36 const gchar *name = gst_structure_get_name (s);
37 GstClockTime endtime;
38
39 if (strcmp (name, "spectrum") == 0) {
40 const GValue *magnitudes;
41 const GValue *phases;
42 const GValue *mag, *phase;
43 gdouble freq;
44 guint i;
45
46 if (!gst_structure_get_clock_time (s, "endtime", &endtime))
47 endtime = GST_CLOCK_TIME_NONE;
48
49 g_print ("New spectrum message, endtime %" GST_TIME_FORMAT "\n",
50 GST_TIME_ARGS (endtime));
51
52 magnitudes = gst_structure_get_value (s, "magnitude");
53 phases = gst_structure_get_value (s, "phase");
54
55 for (i = 0; i < spect_bands; ++i) {
56 freq = (gdouble) ((AUDIOFREQ / 2) * i + AUDIOFREQ / 4) / spect_bands;
57 mag = gst_value_list_get_value (magnitudes, i);
58 phase = gst_value_list_get_value (phases, i);
59
60 if (mag != NULL && phase != NULL) {
61 g_print ("band %d (freq %g): magnitude %f dB phase %f\n", i, freq,
62 g_value_get_float (mag), g_value_get_float (phase));
63 }
64 }
65 g_print ("\n");
66 }
67 }
68 return TRUE;
69 }
70
71 int
main(int argc,char * argv[])72 main (int argc, char *argv[])
73 {
74 GstElement *bin;
75 GstElement *src, *audioconvert, *spectrum, *sink;
76 GstBus *bus;
77 GstCaps *caps;
78 GMainLoop *loop;
79
80 gst_init (&argc, &argv);
81
82 bin = gst_pipeline_new ("bin");
83
84 src = gst_element_factory_make ("audiotestsrc", "src");
85 g_object_set (G_OBJECT (src), "wave", 0, "freq", 6000.0, NULL);
86 audioconvert = gst_element_factory_make ("audioconvert", NULL);
87 g_assert (audioconvert);
88
89 spectrum = gst_element_factory_make ("spectrum", "spectrum");
90 g_object_set (G_OBJECT (spectrum), "bands", spect_bands, "threshold", -80,
91 "post-messages", TRUE, "message-phase", TRUE, NULL);
92
93 sink = gst_element_factory_make ("fakesink", "sink");
94 g_object_set (G_OBJECT (sink), "sync", TRUE, NULL);
95
96 gst_bin_add_many (GST_BIN (bin), src, audioconvert, spectrum, sink, NULL);
97
98 caps = gst_caps_new_simple ("audio/x-raw",
99 "rate", G_TYPE_INT, AUDIOFREQ, NULL);
100
101 if (!gst_element_link (src, audioconvert) ||
102 !gst_element_link_filtered (audioconvert, spectrum, caps) ||
103 !gst_element_link (spectrum, sink)) {
104 fprintf (stderr, "can't link elements\n");
105 exit (1);
106 }
107 gst_caps_unref (caps);
108
109 bus = gst_element_get_bus (bin);
110 gst_bus_add_watch (bus, message_handler, NULL);
111 gst_object_unref (bus);
112
113 gst_element_set_state (bin, GST_STATE_PLAYING);
114
115 /* we need to run a GLib main loop to get the messages */
116 loop = g_main_loop_new (NULL, FALSE);
117 g_main_loop_run (loop);
118
119 gst_element_set_state (bin, GST_STATE_NULL);
120
121 gst_object_unref (bin);
122
123 return 0;
124 }
125