1 /* GStreamer
2 * Copyright (C) <2004> Benjamin Otte <otte@gnome.org>
3 * <2007> Stefan Kost <ensonic@users.sf.net>
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 /**
22 * SECTION:element-equalizer-nbands
23 *
24 * The n-band equalizer element is a fully parametric equalizer. It allows to
25 * select between 1 and 64 bands and has properties on each band to change
26 * the center frequency, band width and gain.
27 *
28 * <refsect2>
29 * <title>Example launch line</title>
30 * |[
31 * gst-launch-1.0 filesrc location=song.ogg ! oggdemux ! vorbisdec ! audioconvert ! equalizer-nbands num-bands=15 band5::gain=6.0 ! alsasink
32 * ]| This make the equalizer use 15 bands and raises the volume of the 5th band by 6 db.
33 * </refsect2>
34 * <refsect2>
35 * <title>Example code</title>
36 * |[
37 * #include <gst/gst.h>
38 *
39 * ...
40 * typedef struct {
41 * gfloat freq;
42 * gfloat width;
43 * gfloat gain;
44 * } GstEqualizerBandState;
45 *
46 * ...
47 *
48 * GstElement *equalizer;
49 * GObject *band;
50 * gint i;
51 * GstEqualizerBandState state[] = {
52 * { 120.0, 50.0, - 3.0},
53 * { 500.0, 20.0, 12.0},
54 * {1503.0, 2.0, -20.0},
55 * {6000.0, 1000.0, 6.0},
56 * {3000.0, 120.0, 2.0}
57 * };
58 *
59 * ...
60 *
61 * equalizer = gst_element_factory_make ("equalizer-nbands", "equalizer");
62 * g_object_set (G_OBJECT (equalizer), "num-bands", 5, NULL);
63 *
64 * ...
65 *
66 * for (i = 0; i < 5; i++) {
67 * band = gst_child_proxy_get_child_by_index (GST_CHILD_PROXY (equalizer), i);
68 * g_object_set (G_OBJECT (band), "freq", state[i].freq,
69 * "bandwidth", state[i].width,
70 * "gain", state[i].gain);
71 * g_object_unref (G_OBJECT (band));
72 * }
73 *
74 * ...
75 * ]|
76 * </refsect2>
77 */
78
79 #ifdef HAVE_CONFIG_H
80 #include "config.h"
81 #endif
82
83 #include "gstiirequalizer.h"
84 #include "gstiirequalizernbands.h"
85
86
87 enum
88 {
89 PROP_NUM_BANDS = 1
90 };
91
92 static void gst_iir_equalizer_nbands_set_property (GObject * object,
93 guint prop_id, const GValue * value, GParamSpec * pspec);
94 static void gst_iir_equalizer_nbands_get_property (GObject * object,
95 guint prop_id, GValue * value, GParamSpec * pspec);
96
97 GST_DEBUG_CATEGORY_EXTERN (equalizer_debug);
98 #define GST_CAT_DEFAULT equalizer_debug
99
100 #define gst_iir_equalizer_nbands_parent_class parent_class
101 G_DEFINE_TYPE (GstIirEqualizerNBands, gst_iir_equalizer_nbands,
102 GST_TYPE_IIR_EQUALIZER);
103
104 /* equalizer implementation */
105
106 static void
gst_iir_equalizer_nbands_class_init(GstIirEqualizerNBandsClass * klass)107 gst_iir_equalizer_nbands_class_init (GstIirEqualizerNBandsClass * klass)
108 {
109 GObjectClass *gobject_class = (GObjectClass *) klass;
110 GstElementClass *gstelement_class = (GstElementClass *) klass;
111
112 gobject_class->set_property = gst_iir_equalizer_nbands_set_property;
113 gobject_class->get_property = gst_iir_equalizer_nbands_get_property;
114
115 g_object_class_install_property (gobject_class, PROP_NUM_BANDS,
116 g_param_spec_uint ("num-bands", "num-bands",
117 "number of different bands to use", 1, 64, 10,
118 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_CONSTRUCT));
119
120 gst_element_class_set_static_metadata (gstelement_class, "N Band Equalizer",
121 "Filter/Effect/Audio",
122 "Direct Form IIR equalizer",
123 "Benjamin Otte <otte@gnome.org>," " Stefan Kost <ensonic@users.sf.net>");
124 }
125
126 static void
gst_iir_equalizer_nbands_init(GstIirEqualizerNBands * equ_n)127 gst_iir_equalizer_nbands_init (GstIirEqualizerNBands * equ_n)
128 {
129 GstIirEqualizer *equ = GST_IIR_EQUALIZER (equ_n);
130
131 gst_iir_equalizer_compute_frequencies (equ, 10);
132 }
133
134 static void
gst_iir_equalizer_nbands_set_property(GObject * object,guint prop_id,const GValue * value,GParamSpec * pspec)135 gst_iir_equalizer_nbands_set_property (GObject * object, guint prop_id,
136 const GValue * value, GParamSpec * pspec)
137 {
138 GstIirEqualizer *equ = GST_IIR_EQUALIZER (object);
139
140 switch (prop_id) {
141 case PROP_NUM_BANDS:
142 gst_iir_equalizer_compute_frequencies (equ, g_value_get_uint (value));
143 break;
144 default:
145 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
146 break;
147 }
148 }
149
150 static void
gst_iir_equalizer_nbands_get_property(GObject * object,guint prop_id,GValue * value,GParamSpec * pspec)151 gst_iir_equalizer_nbands_get_property (GObject * object, guint prop_id,
152 GValue * value, GParamSpec * pspec)
153 {
154 GstIirEqualizer *equ = GST_IIR_EQUALIZER (object);
155
156 switch (prop_id) {
157 case PROP_NUM_BANDS:
158 g_value_set_uint (value, equ->freq_band_count);
159 break;
160 default:
161 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
162 break;
163 }
164 }
165