gst-plugins-good  1.20.3
About: GStreamer (Good Plugins) is a library for constructing of graphs of media-handling components. A set of good-quality plug-ins (under LGPL license).
  Fossies Dox: gst-plugins-good-1.20.3.tar.xz  ("unofficial" and yet experimental doxygen-generated source code documentation)  

audioiirfilter.c
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1/*
2 * GStreamer
3 * Copyright (C) 2009 Sebastian Dröge <sebastian.droege@collabora.co.uk>
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/**
23 * SECTION:element-audioiirfilter
24 * @title: audioiirfilter
25 *
26 * audioiirfilter implements a generic audio
27 * [IIR filter](http://en.wikipedia.org/wiki/Infinite_impulse_response).
28 * Before usage the "a" and "b" properties have to be set to the filter
29 * coefficients that should be used.
30 *
31 * The filter coefficients describe the numerator and denominator of the
32 * transfer function.
33 *
34 * To change the filter coefficients whenever the sampling rate changes the
35 * "rate-changed" signal can be used. This should be done for most
36 * IIR filters as they're depending on the sampling rate.
37 *
38 * ## Example application
39 * <programlisting language="C">
40 * <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" parse="text" href="../../../../tests/examples/audiofx/iirfilter-example.c" />
41 * ]|
42 *
43 */
44
45/* FIXME 0.11: suppress warnings for deprecated API such as GValueArray
46 * with newer GLib versions (>= 2.31.0) */
47#define GLIB_DISABLE_DEPRECATION_WARNINGS
48
49#ifdef HAVE_CONFIG_H
50#include "config.h"
51#endif
52
53#include <string.h>
54#include <math.h>
55#include <gst/gst.h>
56#include <gst/audio/gstaudiofilter.h>
57
58#include "audioiirfilter.h"
59
61
62#define GST_CAT_DEFAULT gst_audio_iir_filter_debug
64
65enum
66{
69};
70
71enum
72{
75 PROP_B
76};
77
79
80#define gst_audio_iir_filter_parent_class parent_class
81G_DEFINE_TYPE (GstAudioIIRFilter, gst_audio_iir_filter,
83GST_ELEMENT_REGISTER_DEFINE (audioiirfilter, "audioiirfilter",
84 GST_RANK_NONE, GST_TYPE_AUDIO_IIR_FILTER);
85
86static void gst_audio_iir_filter_set_property (GObject * object, guint prop_id,
87 const GValue * value, GParamSpec * pspec);
88static void gst_audio_iir_filter_get_property (GObject * object, guint prop_id,
89 GValue * value, GParamSpec * pspec);
90static void gst_audio_iir_filter_finalize (GObject * object);
91
92static gboolean gst_audio_iir_filter_setup (GstAudioFilter * base,
93 const GstAudioInfo * info);
94
95static void
97{
98 GObjectClass *gobject_class = (GObjectClass *) klass;
99 GstElementClass *gstelement_class = (GstElementClass *) klass;
100 GstAudioFilterClass *filter_class = (GstAudioFilterClass *) klass;
101
102 GST_DEBUG_CATEGORY_INIT (gst_audio_iir_filter_debug, "audioiirfilter", 0,
103 "Generic audio IIR filter plugin");
104
105 gobject_class->set_property = gst_audio_iir_filter_set_property;
106 gobject_class->get_property = gst_audio_iir_filter_get_property;
107 gobject_class->finalize = gst_audio_iir_filter_finalize;
108
109 g_object_class_install_property (gobject_class, PROP_A,
110 g_param_spec_value_array ("a", "A",
111 "Filter coefficients (denominator of transfer function)",
112 g_param_spec_double ("Coefficient", "Filter Coefficient",
113 "Filter coefficient", -G_MAXDOUBLE, G_MAXDOUBLE, 0.0,
114 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS),
115 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
116 g_object_class_install_property (gobject_class, PROP_B,
117 g_param_spec_value_array ("b", "B",
118 "Filter coefficients (numerator of transfer function)",
119 g_param_spec_double ("Coefficient", "Filter Coefficient",
120 "Filter coefficient", -G_MAXDOUBLE, G_MAXDOUBLE, 0.0,
121 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS),
122 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
123
124 filter_class->setup = GST_DEBUG_FUNCPTR (gst_audio_iir_filter_setup);
125
126 /**
127 * GstAudioIIRFilter::rate-changed:
128 * @filter: the filter on which the signal is emitted
129 * @rate: the new sampling rate
130 *
131 * Will be emitted when the sampling rate changes. The callbacks
132 * will be called from the streaming thread and processing will
133 * stop until the event is handled.
134 */
136 g_signal_new ("rate-changed", G_TYPE_FROM_CLASS (klass),
137 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstAudioIIRFilterClass, rate_changed),
138 NULL, NULL, NULL, G_TYPE_NONE, 1, G_TYPE_INT);
139
140 gst_element_class_set_static_metadata (gstelement_class,
141 "Audio IIR filter", "Filter/Effect/Audio",
142 "Generic audio IIR filter with custom filter kernel",
143 "Sebastian Dröge <sebastian.droege@collabora.co.uk>");
144}
145
146static void
148 GValueArray * va, GValueArray * vb)
149{
150 gdouble *a = NULL, *b = NULL;
151 guint i;
152
153 if (va) {
154 if (self->a)
155 g_value_array_free (self->a);
156
157 self->a = va;
158 }
159 if (vb) {
160 if (self->b)
161 g_value_array_free (self->b);
162
163 self->b = vb;
164 }
165
166 if (self->a && self->a->n_values > 0) {
167 a = g_new (gdouble, self->a->n_values);
168
169 for (i = 0; i < self->a->n_values; i++) {
170 GValue *v = g_value_array_get_nth (self->a, i);
171 a[i] = g_value_get_double (v);
172 }
173 }
174
175 if (self->b && self->b->n_values > 0) {
176 b = g_new (gdouble, self->b->n_values);
177 for (i = 0; i < self->b->n_values; i++) {
178 GValue *v = g_value_array_get_nth (self->b, i);
179 b[i] = g_value_get_double (v);
180 }
181 }
182
184 (self), a, (self->a) ? self->a->n_values : 0, b,
185 (self->b) ? self->b->n_values : 0);
186}
187
188static void
190{
191 GValue v = { 0, };
192 GValueArray *a;
193
194 a = g_value_array_new (1);
195
196 g_value_init (&v, G_TYPE_DOUBLE);
197 g_value_set_double (&v, 1.0);
198 g_value_array_append (a, &v);
199 g_value_unset (&v);
200
201 gst_audio_iir_filter_update_coefficients (self, a, g_value_array_copy (a));
202
203 g_mutex_init (&self->lock);
204}
205
206/* GstAudioFilter vmethod implementations */
207
208/* get notified of caps and plug in the correct process function */
209static gboolean
210gst_audio_iir_filter_setup (GstAudioFilter * base, const GstAudioInfo * info)
211{
213 gint new_rate = GST_AUDIO_INFO_RATE (info);
214
215 if (GST_AUDIO_FILTER_RATE (self) != new_rate) {
216 g_signal_emit (G_OBJECT (self),
218 }
219
220 return GST_AUDIO_FILTER_CLASS (parent_class)->setup (base, info);
221}
222
223static void
225{
227
228 g_mutex_clear (&self->lock);
229
230 if (self->a)
231 g_value_array_free (self->a);
232 self->a = NULL;
233 if (self->b)
234 g_value_array_free (self->b);
235 self->b = NULL;
236
237 G_OBJECT_CLASS (parent_class)->finalize (object);
238}
239
240static void
241gst_audio_iir_filter_set_property (GObject * object, guint prop_id,
242 const GValue * value, GParamSpec * pspec)
243{
245
246 g_return_if_fail (GST_IS_AUDIO_IIR_FILTER (self));
247
248 switch (prop_id) {
249 case PROP_A:
250 g_mutex_lock (&self->lock);
251 gst_audio_iir_filter_update_coefficients (self, g_value_dup_boxed (value),
252 NULL);
253 g_mutex_unlock (&self->lock);
254 break;
255 case PROP_B:
256 g_mutex_lock (&self->lock);
258 g_value_dup_boxed (value));
259 g_mutex_unlock (&self->lock);
260 break;
261 default:
262 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
263 break;
264 }
265}
266
267static void
268gst_audio_iir_filter_get_property (GObject * object, guint prop_id,
269 GValue * value, GParamSpec * pspec)
270{
272
273 switch (prop_id) {
274 case PROP_A:
275 g_value_set_boxed (value, self->a);
276 break;
277 case PROP_B:
278 g_value_set_boxed (value, self->b);
279 break;
280 default:
281 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
282 break;
283 }
284}
void gst_audio_fx_base_iir_filter_set_coefficients(GstAudioFXBaseIIRFilter *filter, gdouble *a, guint na, gdouble *b, guint nb)
#define GST_AUDIO_FX_BASE_IIR_FILTER(obj)
#define GST_TYPE_AUDIO_FX_BASE_IIR_FILTER
G_DEFINE_TYPE(GstAudioIIRFilter, gst_audio_iir_filter,(gst_audio_fx_base_iir_filter_get_type()))
static void gst_audio_iir_filter_init(GstAudioIIRFilter *self)
@ PROP_A
@ PROP_B
@ PROP_0
static void gst_audio_iir_filter_get_property(GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
@ LAST_SIGNAL
@ SIGNAL_RATE_CHANGED
static void gst_audio_iir_filter_class_init(GstAudioIIRFilterClass *klass)
static guint gst_audio_iir_filter_signals[LAST_SIGNAL]
GST_ELEMENT_REGISTER_DEFINE(audioiirfilter, "audioiirfilter", GST_RANK_NONE,(gst_audio_iir_filter_get_type()))
static void gst_audio_iir_filter_update_coefficients(GstAudioIIRFilter *self, GValueArray *va, GValueArray *vb)
static void gst_audio_iir_filter_finalize(GObject *object)
static void gst_audio_iir_filter_set_property(GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
#define GST_CAT_DEFAULT
static gboolean gst_audio_iir_filter_setup(GstAudioFilter *base, const GstAudioInfo *info)
GST_DEBUG_CATEGORY_STATIC(gst_audio_iir_filter_debug)
#define GST_IS_AUDIO_IIR_FILTER(obj)
#define GST_TYPE_AUDIO_IIR_FILTER
#define GST_AUDIO_IIR_FILTER(obj)
#define parent_class
Definition: gstsbcparse.c:83
GValueArray * a
GValueArray * b