blob: 0882017d84c75445a0b5ccc487a0a63864c96a9c [file] [log] [blame]
/*
* GStreamer
* Copyright (C) 2009 Sebastian Dröge <sebastian.droege@collabora.co.uk>
*
* 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.
*
*/
/**
* SECTION:element-audioiirfilter
*
* audioiirfilter implements a generic audio <ulink url="http://en.wikipedia.org/wiki/Infinite_impulse_response">IIR filter</ulink>. Before usage the
* "a" and "b" properties have to be set to the filter coefficients that
* should be used.
*
* The filter coefficients describe the numerator and denominator of the
* transfer function.
*
* To change the filter coefficients whenever the sampling rate changes the
* "rate-changed" signal can be used. This should be done for most
* IIR filters as they're depending on the sampling rate.
*
* <refsect2>
* <title>Example application</title>
* |[
* <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" parse="text" href="../../../../tests/examples/audiofx/iirfilter-example.c" />
* ]|
* </refsect2>
*/
/* FIXME 0.11: suppress warnings for deprecated API such as GValueArray
* with newer GLib versions (>= 2.31.0) */
#define GLIB_DISABLE_DEPRECATION_WARNINGS
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include <math.h>
#include <gst/gst.h>
#include <gst/audio/gstaudiofilter.h>
#include "audioiirfilter.h"
#include "gst/glib-compat-private.h"
#define GST_CAT_DEFAULT gst_audio_iir_filter_debug
GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
enum
{
SIGNAL_RATE_CHANGED,
LAST_SIGNAL
};
enum
{
PROP_0,
PROP_A,
PROP_B
};
static guint gst_audio_iir_filter_signals[LAST_SIGNAL] = { 0, };
#define gst_audio_iir_filter_parent_class parent_class
G_DEFINE_TYPE (GstAudioIIRFilter, gst_audio_iir_filter,
GST_TYPE_AUDIO_FX_BASE_IIR_FILTER);
static void gst_audio_iir_filter_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_audio_iir_filter_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static void gst_audio_iir_filter_finalize (GObject * object);
static gboolean gst_audio_iir_filter_setup (GstAudioFilter * base,
const GstAudioInfo * info);
static void
gst_audio_iir_filter_class_init (GstAudioIIRFilterClass * klass)
{
GObjectClass *gobject_class = (GObjectClass *) klass;
GstElementClass *gstelement_class = (GstElementClass *) klass;
GstAudioFilterClass *filter_class = (GstAudioFilterClass *) klass;
GST_DEBUG_CATEGORY_INIT (gst_audio_iir_filter_debug, "audioiirfilter", 0,
"Generic audio IIR filter plugin");
gobject_class->set_property = gst_audio_iir_filter_set_property;
gobject_class->get_property = gst_audio_iir_filter_get_property;
gobject_class->finalize = gst_audio_iir_filter_finalize;
g_object_class_install_property (gobject_class, PROP_A,
g_param_spec_value_array ("a", "A",
"Filter coefficients (denominator of transfer function)",
g_param_spec_double ("Coefficient", "Filter Coefficient",
"Filter coefficient", -G_MAXDOUBLE, G_MAXDOUBLE, 0.0,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS),
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_B,
g_param_spec_value_array ("b", "B",
"Filter coefficients (numerator of transfer function)",
g_param_spec_double ("Coefficient", "Filter Coefficient",
"Filter coefficient", -G_MAXDOUBLE, G_MAXDOUBLE, 0.0,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS),
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
filter_class->setup = GST_DEBUG_FUNCPTR (gst_audio_iir_filter_setup);
/**
* GstAudioIIRFilter::rate-changed:
* @filter: the filter on which the signal is emitted
* @rate: the new sampling rate
*
* Will be emitted when the sampling rate changes. The callbacks
* will be called from the streaming thread and processing will
* stop until the event is handled.
*/
gst_audio_iir_filter_signals[SIGNAL_RATE_CHANGED] =
g_signal_new ("rate-changed", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstAudioIIRFilterClass, rate_changed),
NULL, NULL, NULL, G_TYPE_NONE, 1, G_TYPE_INT);
gst_element_class_set_static_metadata (gstelement_class,
"Audio IIR filter", "Filter/Effect/Audio",
"Generic audio IIR filter with custom filter kernel",
"Sebastian Dröge <sebastian.droege@collabora.co.uk>");
}
static void
gst_audio_iir_filter_update_coefficients (GstAudioIIRFilter * self,
GValueArray * va, GValueArray * vb)
{
gdouble *a = NULL, *b = NULL;
guint i;
if (va) {
if (self->a)
g_value_array_free (self->a);
self->a = va;
}
if (vb) {
if (self->b)
g_value_array_free (self->b);
self->b = vb;
}
if (self->a && self->a->n_values > 0) {
a = g_new (gdouble, self->a->n_values);
for (i = 0; i < self->a->n_values; i++) {
GValue *v = g_value_array_get_nth (self->a, i);
a[i] = g_value_get_double (v);
}
}
if (self->b && self->b->n_values > 0) {
b = g_new (gdouble, self->b->n_values);
for (i = 0; i < self->b->n_values; i++) {
GValue *v = g_value_array_get_nth (self->b, i);
b[i] = g_value_get_double (v);
}
}
gst_audio_fx_base_iir_filter_set_coefficients (GST_AUDIO_FX_BASE_IIR_FILTER
(self), a, (self->a) ? self->a->n_values : 0, b,
(self->b) ? self->b->n_values : 0);
}
static void
gst_audio_iir_filter_init (GstAudioIIRFilter * self)
{
GValue v = { 0, };
GValueArray *a, *b;
a = g_value_array_new (1);
g_value_init (&v, G_TYPE_DOUBLE);
g_value_set_double (&v, 1.0);
g_value_array_append (a, &v);
g_value_unset (&v);
b = NULL;
gst_audio_iir_filter_update_coefficients (self, a, b);
g_mutex_init (&self->lock);
}
/* GstAudioFilter vmethod implementations */
/* get notified of caps and plug in the correct process function */
static gboolean
gst_audio_iir_filter_setup (GstAudioFilter * base, const GstAudioInfo * info)
{
GstAudioIIRFilter *self = GST_AUDIO_IIR_FILTER (base);
gint new_rate = GST_AUDIO_INFO_RATE (info);
if (GST_AUDIO_FILTER_RATE (self) != new_rate) {
g_signal_emit (G_OBJECT (self),
gst_audio_iir_filter_signals[SIGNAL_RATE_CHANGED], 0, new_rate);
}
return GST_AUDIO_FILTER_CLASS (parent_class)->setup (base, info);
}
static void
gst_audio_iir_filter_finalize (GObject * object)
{
GstAudioIIRFilter *self = GST_AUDIO_IIR_FILTER (object);
g_mutex_clear (&self->lock);
if (self->a)
g_value_array_free (self->a);
self->a = NULL;
if (self->b)
g_value_array_free (self->b);
self->b = NULL;
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static void
gst_audio_iir_filter_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstAudioIIRFilter *self = GST_AUDIO_IIR_FILTER (object);
g_return_if_fail (GST_IS_AUDIO_IIR_FILTER (self));
switch (prop_id) {
case PROP_A:
g_mutex_lock (&self->lock);
gst_audio_iir_filter_update_coefficients (self, g_value_dup_boxed (value),
NULL);
g_mutex_unlock (&self->lock);
break;
case PROP_B:
g_mutex_lock (&self->lock);
gst_audio_iir_filter_update_coefficients (self, NULL,
g_value_dup_boxed (value));
g_mutex_unlock (&self->lock);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_audio_iir_filter_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstAudioIIRFilter *self = GST_AUDIO_IIR_FILTER (object);
switch (prop_id) {
case PROP_A:
g_value_set_boxed (value, self->a);
break;
case PROP_B:
g_value_set_boxed (value, self->b);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}