gstreamer/gst/equalizer/gstiirequalizer.c
Ghislain 'Aus' Lacroix 9507cdc84c equalizer: Use floating point arithmetic internally for the int16 mode
By using int32 arithmetic we will introduce distortions as the
IIR filter is very sensitive to rounding errors. Fixes bug .
2009-05-28 12:39:46 +02:00

750 lines
25 KiB
C

/* GStreamer
* Copyright (C) <2004> Benjamin Otte <otte@gnome.org>
* <2007> Stefan Kost <ensonic@users.sf.net>
* <2007> Sebastian Dröge <slomo@circular-chaos.org>
*
* 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.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <math.h>
#include <string.h>
#include "gstiirequalizer.h"
#include "gstiirequalizernbands.h"
#include "gstiirequalizer3bands.h"
#include "gstiirequalizer10bands.h"
GST_DEBUG_CATEGORY (equalizer_debug);
#define GST_CAT_DEFAULT equalizer_debug
static void gst_iir_equalizer_child_proxy_interface_init (gpointer g_iface,
gpointer iface_data);
static void gst_iir_equalizer_finalize (GObject * object);
static gboolean gst_iir_equalizer_setup (GstAudioFilter * filter,
GstRingBufferSpec * fmt);
static GstFlowReturn gst_iir_equalizer_transform_ip (GstBaseTransform * btrans,
GstBuffer * buf);
GST_DEBUG_CATEGORY_EXTERN (equalizer_debug);
#define GST_CAT_DEFAULT equalizer_debug
#define ALLOWED_CAPS \
"audio/x-raw-int," \
" depth=(int)16," \
" width=(int)16," \
" endianness=(int)BYTE_ORDER," \
" signed=(bool)TRUE," \
" rate=(int)[1000,MAX]," \
" channels=(int)[1,MAX]; " \
"audio/x-raw-float," \
" width=(int) { 32, 64 } ," \
" endianness=(int)BYTE_ORDER," \
" rate=(int)[1000,MAX]," \
" channels=(int)[1,MAX]"
static void
_do_init (GType object_type)
{
const GInterfaceInfo child_proxy_interface_info = {
(GInterfaceInitFunc) gst_iir_equalizer_child_proxy_interface_init,
NULL, /* interface_finalize */
NULL /* interface_data */
};
g_type_add_interface_static (object_type, GST_TYPE_CHILD_PROXY,
&child_proxy_interface_info);
}
GST_BOILERPLATE_FULL (GstIirEqualizer, gst_iir_equalizer,
GstAudioFilter, GST_TYPE_AUDIO_FILTER, _do_init);
/* child object */
enum
{
ARG_GAIN = 1,
ARG_FREQ,
ARG_BANDWIDTH
};
typedef struct _GstIirEqualizerBandClass GstIirEqualizerBandClass;
#define GST_TYPE_IIR_EQUALIZER_BAND \
(gst_iir_equalizer_band_get_type())
#define GST_IIR_EQUALIZER_BAND(obj) \
(G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_IIR_EQUALIZER_BAND,GstIirEqualizerBand))
#define GST_IIR_EQUALIZER_BAND_CLASS(klass) \
(G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_IIR_EQUALIZER_BAND,GstIirEqualizerBandClass))
#define GST_IS_IIR_EQUALIZER_BAND(obj) \
(G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_IIR_EQUALIZER_BAND))
#define GST_IS_IIR_EQUALIZER_BAND_CLASS(klass) \
(G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_IIR_EQUALIZER_BAND))
struct _GstIirEqualizerBand
{
GstObject object;
/*< private > */
/* center frequency and gain */
gdouble freq;
gdouble gain;
gdouble width;
/* second order iir filter */
gdouble b1, b2; /* IIR coefficients for outputs */
gdouble a0, a1, a2; /* IIR coefficients for inputs */
};
struct _GstIirEqualizerBandClass
{
GstObjectClass parent_class;
};
static GType gst_iir_equalizer_band_get_type (void);
static void setup_filter (GstIirEqualizer * equ, GstIirEqualizerBand * band);
static void set_passthrough (GstIirEqualizer * equ);
static void
gst_iir_equalizer_band_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstIirEqualizerBand *band = GST_IIR_EQUALIZER_BAND (object);
switch (prop_id) {
case ARG_GAIN:{
gdouble gain;
gain = g_value_get_double (value);
GST_DEBUG_OBJECT (band, "gain = %lf -> %lf", band->gain, gain);
if (gain != band->gain) {
GstIirEqualizer *equ =
GST_IIR_EQUALIZER (gst_object_get_parent (GST_OBJECT (band)));
equ->need_new_coefficients = TRUE;
band->gain = gain;
gst_object_unref (equ);
GST_DEBUG_OBJECT (band, "changed gain = %lf ", band->gain);
}
break;
}
case ARG_FREQ:{
gdouble freq;
freq = g_value_get_double (value);
GST_DEBUG_OBJECT (band, "freq = %lf -> %lf", band->freq, freq);
if (freq != band->freq) {
GstIirEqualizer *equ =
GST_IIR_EQUALIZER (gst_object_get_parent (GST_OBJECT (band)));
equ->need_new_coefficients = TRUE;
band->freq = freq;
gst_object_unref (equ);
GST_DEBUG_OBJECT (band, "changed freq = %lf ", band->freq);
}
break;
}
case ARG_BANDWIDTH:{
gdouble width;
width = g_value_get_double (value);
GST_DEBUG_OBJECT (band, "width = %lf -> %lf", band->width, width);
if (width != band->width) {
GstIirEqualizer *equ =
GST_IIR_EQUALIZER (gst_object_get_parent (GST_OBJECT (band)));
equ->need_new_coefficients = TRUE;
band->width = width;
gst_object_unref (equ);
GST_DEBUG_OBJECT (band, "changed width = %lf ", band->width);
}
break;
}
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_iir_equalizer_band_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstIirEqualizerBand *band = GST_IIR_EQUALIZER_BAND (object);
switch (prop_id) {
case ARG_GAIN:
g_value_set_double (value, band->gain);
break;
case ARG_FREQ:
g_value_set_double (value, band->freq);
break;
case ARG_BANDWIDTH:
g_value_set_double (value, band->width);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_iir_equalizer_band_class_init (GstIirEqualizerBandClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
gobject_class->set_property = gst_iir_equalizer_band_set_property;
gobject_class->get_property = gst_iir_equalizer_band_get_property;
g_object_class_install_property (gobject_class, ARG_GAIN,
g_param_spec_double ("gain", "gain",
"gain for the frequency band ranging from -24.0 dB to +12.0 dB",
-24.0, 12.0, 0.0, G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE));
g_object_class_install_property (gobject_class, ARG_FREQ,
g_param_spec_double ("freq", "freq",
"center frequency of the band",
0.0, 100000.0, 0.0, G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE));
g_object_class_install_property (gobject_class, ARG_BANDWIDTH,
g_param_spec_double ("bandwidth", "bandwidth",
"difference between bandedges in Hz",
0.0, 100000.0, 1.0, G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE));
}
static void
gst_iir_equalizer_band_init (GstIirEqualizerBand * band,
GstIirEqualizerBandClass * klass)
{
band->freq = 0.0;
band->gain = 0.0;
band->width = 1.0;
}
static GType
gst_iir_equalizer_band_get_type (void)
{
static GType type = 0;
if (G_UNLIKELY (!type)) {
const GTypeInfo type_info = {
sizeof (GstIirEqualizerBandClass),
NULL,
NULL,
(GClassInitFunc) gst_iir_equalizer_band_class_init,
NULL,
NULL,
sizeof (GstIirEqualizerBand),
0,
(GInstanceInitFunc) gst_iir_equalizer_band_init,
};
type =
g_type_register_static (GST_TYPE_OBJECT, "GstIirEqualizerBand",
&type_info, 0);
}
return (type);
}
/* child proxy iface */
static GstObject *
gst_iir_equalizer_child_proxy_get_child_by_index (GstChildProxy * child_proxy,
guint index)
{
GstIirEqualizer *equ = GST_IIR_EQUALIZER (child_proxy);
g_return_val_if_fail (index < equ->freq_band_count, NULL);
GST_LOG ("return child[%d] '%s'", index, GST_OBJECT_NAME (equ->bands[index]));
return (gst_object_ref (equ->bands[index]));
}
static guint
gst_iir_equalizer_child_proxy_get_children_count (GstChildProxy * child_proxy)
{
GstIirEqualizer *equ = GST_IIR_EQUALIZER (child_proxy);
GST_LOG ("we have %d children", equ->freq_band_count);
return (equ->freq_band_count);
}
static void
gst_iir_equalizer_child_proxy_interface_init (gpointer g_iface,
gpointer iface_data)
{
GstChildProxyInterface *iface = g_iface;
GST_DEBUG ("initializing iface");
iface->get_child_by_index = gst_iir_equalizer_child_proxy_get_child_by_index;
iface->get_children_count = gst_iir_equalizer_child_proxy_get_children_count;
}
/* equalizer implementation */
static void
gst_iir_equalizer_base_init (gpointer g_class)
{
GstAudioFilterClass *audiofilter_class = GST_AUDIO_FILTER_CLASS (g_class);
GstCaps *caps;
caps = gst_caps_from_string (ALLOWED_CAPS);
gst_audio_filter_class_add_pad_templates (audiofilter_class, caps);
gst_caps_unref (caps);
}
static void
gst_iir_equalizer_class_init (GstIirEqualizerClass * klass)
{
GstAudioFilterClass *audio_filter_class = (GstAudioFilterClass *) klass;
GstBaseTransformClass *btrans_class = (GstBaseTransformClass *) klass;
GObjectClass *gobject_class = (GObjectClass *) klass;
gobject_class->finalize = gst_iir_equalizer_finalize;
audio_filter_class->setup = gst_iir_equalizer_setup;
btrans_class->transform_ip = gst_iir_equalizer_transform_ip;
}
static void
gst_iir_equalizer_init (GstIirEqualizer * eq, GstIirEqualizerClass * g_class)
{
eq->need_new_coefficients = TRUE;
}
static void
gst_iir_equalizer_finalize (GObject * object)
{
GstIirEqualizer *equ = GST_IIR_EQUALIZER (object);
gint i;
for (i = 0; i < equ->freq_band_count; i++) {
if (equ->bands[i])
gst_object_unparent (GST_OBJECT (equ->bands[i]));
equ->bands[i] = NULL;
}
equ->freq_band_count = 0;
g_free (equ->bands);
g_free (equ->history);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static inline gdouble
arg_to_scale (gdouble arg)
{
return (pow (10.0, arg / 20.0));
}
/* Filter taken from
*
* The Equivalence of Various Methods of Computing
* Biquad Coefficients for Audio Parametric Equalizers
*
* by Robert Bristow-Johnson
*
* http://www.aes.org/e-lib/browse.cfm?elib=6326
* http://www.musicdsp.org/files/EQ-Coefficients.pdf
*
* The bandwidth method that we use here is the preferred
* one from this article transformed from octaves to frequency
* in Hz.
*/
static void
setup_filter (GstIirEqualizer * equ, GstIirEqualizerBand * band)
{
g_return_if_fail (GST_AUDIO_FILTER (equ)->format.rate);
/* FIXME: we need better filters
* - we need shelf-filter for 1st and last band
*/
{
gdouble gain, omega, bw;
gdouble edge_gain, gamma;
gdouble alpha, beta;
gain = arg_to_scale (band->gain);
if (band->freq / GST_AUDIO_FILTER (equ)->format.rate >= 0.5)
omega = M_PI;
else if (band->freq <= 0.0)
omega = 0.0;
else
omega = 2.0 * M_PI * (band->freq / GST_AUDIO_FILTER (equ)->format.rate);
if (band->width / GST_AUDIO_FILTER (equ)->format.rate >= 0.5) {
/* If bandwidth == 0.5 the calculation below fails as tan(M_PI/2)
* is undefined. So set the bandwidth to a slightly smaller value.
*/
bw = M_PI - 0.00000001;
} else if (band->width <= 0.0) {
/* If bandwidth == 0 this band won't change anything so set
* the coefficients accordingly. The coefficient calculation
* below would create coefficients that for some reason amplify
* the band.
*/
band->a0 = 1.0;
band->a1 = 0.0;
band->a2 = 0.0;
band->b1 = 0.0;
band->b2 = 0.0;
gain = 1.0;
goto out;
} else {
bw = 2.0 * M_PI * (band->width / GST_AUDIO_FILTER (equ)->format.rate);
}
edge_gain = sqrt (gain);
gamma = tan (bw / 2.0);
alpha = gamma * edge_gain;
beta = gamma / edge_gain;
band->a0 = (1.0 + alpha) / (1.0 + beta);
band->a1 = (-2.0 * cos (omega)) / (1.0 + beta);
band->a2 = (1.0 - alpha) / (1.0 + beta);
band->b1 = (2.0 * cos (omega)) / (1.0 + beta);
band->b2 = -(1.0 - beta) / (1.0 + beta);
out:
GST_INFO
("gain = %5.1f, width= %7.2f, freq = %7.2f, a0 = %7.5g, a1 = %7.5g, a2=%7.5g b1 = %7.5g, b2 = %7.5g",
band->gain, band->width, band->freq, band->a0, band->a1, band->a2,
band->b1, band->b2);
}
}
static void
set_passthrough (GstIirEqualizer * equ)
{
gint i;
gboolean passthrough = TRUE;
for (i = 0; i < equ->freq_band_count; i++) {
passthrough = passthrough && (equ->bands[i]->gain == 0.0);
}
gst_base_transform_set_passthrough (GST_BASE_TRANSFORM (equ), passthrough);
GST_DEBUG ("Passthrough mode: %d\n", passthrough);
}
static void
update_coefficients (GstIirEqualizer * equ)
{
gint i;
for (i = 0; i < equ->freq_band_count; i++) {
setup_filter (equ, equ->bands[i]);
}
equ->need_new_coefficients = FALSE;
}
static void
alloc_history (GstIirEqualizer * equ)
{
/* free + alloc = no memcpy */
g_free (equ->history);
equ->history =
g_malloc0 (equ->history_size * GST_AUDIO_FILTER (equ)->format.channels *
equ->freq_band_count);
}
void
gst_iir_equalizer_compute_frequencies (GstIirEqualizer * equ, guint new_count)
{
guint old_count, i;
gdouble freq0, freq1, step;
gchar name[20];
if (equ->freq_band_count == new_count)
return;
old_count = equ->freq_band_count;
equ->freq_band_count = new_count;
GST_DEBUG ("bands %u -> %u", old_count, new_count);
if (old_count < new_count) {
/* add new bands */
equ->bands = g_realloc (equ->bands, sizeof (GstObject *) * new_count);
for (i = old_count; i < new_count; i++) {
equ->bands[i] = g_object_new (GST_TYPE_IIR_EQUALIZER_BAND, NULL);
/* otherwise they get names like 'iirequalizerband5' */
sprintf (name, "band%u", i);
gst_object_set_name (GST_OBJECT (equ->bands[i]), name);
GST_DEBUG ("adding band[%d]=%p", i, equ->bands[i]);
gst_object_set_parent (GST_OBJECT (equ->bands[i]), GST_OBJECT (equ));
gst_child_proxy_child_added (GST_OBJECT (equ),
GST_OBJECT (equ->bands[i]));
}
} else {
/* free unused bands */
for (i = new_count; i < old_count; i++) {
GST_DEBUG ("removing band[%d]=%p", i, equ->bands[i]);
gst_child_proxy_child_removed (GST_OBJECT (equ),
GST_OBJECT (equ->bands[i]));
gst_object_unparent (GST_OBJECT (equ->bands[i]));
equ->bands[i] = NULL;
}
}
alloc_history (equ);
/* set center frequencies and name band objects
* FIXME: arg! we can't change the name of parented objects :(
* application should read band->freq to get the name
*/
step = pow (HIGHEST_FREQ / LOWEST_FREQ, 1.0 / new_count);
freq0 = LOWEST_FREQ;
for (i = 0; i < new_count; i++) {
freq1 = freq0 * step;
equ->bands[i]->freq = freq0 + ((freq1 - freq0) / 2.0);
equ->bands[i]->width = freq1 - freq0;
GST_DEBUG ("band[%2d] = '%lf'", i, equ->bands[i]->freq);
/*
if(equ->bands[i]->freq<10000.0)
sprintf (name,"%dHz",(gint)equ->bands[i]->freq);
else
sprintf (name,"%dkHz",(gint)(equ->bands[i]->freq/1000.0));
gst_object_set_name( GST_OBJECT (equ->bands[i]), name);
GST_DEBUG ("band[%2d] = '%s'",i,name);
*/
freq0 = freq1;
}
equ->need_new_coefficients = TRUE;
}
/* start of code that is type specific */
#define CREATE_OPTIMIZED_FUNCTIONS_INT(TYPE,BIG_TYPE,MIN_VAL,MAX_VAL) \
typedef struct { \
BIG_TYPE x1, x2; /* history of input values for a filter */ \
BIG_TYPE y1, y2; /* history of output values for a filter */ \
} SecondOrderHistory ## TYPE; \
\
static inline BIG_TYPE \
one_step_ ## TYPE (GstIirEqualizerBand *filter, \
SecondOrderHistory ## TYPE *history, BIG_TYPE input) \
{ \
/* calculate output */ \
BIG_TYPE output = filter->a0 * input + \
filter->a1 * history->x1 + filter->a2 * history->x2 + \
filter->b1 * history->y1 + filter->b2 * history->y2; \
/* update history */ \
history->y2 = history->y1; \
history->y1 = output; \
history->x2 = history->x1; \
history->x1 = input; \
\
return output; \
} \
\
static const guint \
history_size_ ## TYPE = sizeof (SecondOrderHistory ## TYPE); \
\
static void \
gst_iir_equ_process_ ## TYPE (GstIirEqualizer *equ, guint8 *data, \
guint size, guint channels) \
{ \
guint frames = size / channels / sizeof (TYPE); \
guint i, c, f; \
BIG_TYPE cur; \
\
for (i = 0; i < frames; i++) { \
for (c = 0; c < channels; c++) { \
SecondOrderHistory ## TYPE *history = equ->history; \
cur = *((TYPE *) data); \
for (f = 0; f < equ->freq_band_count; f++) { \
GstIirEqualizerBand *filter = equ->bands[f]; \
\
cur = one_step_ ## TYPE (filter, history, cur); \
history++; \
} \
cur = CLAMP (cur, MIN_VAL, MAX_VAL); \
*((TYPE *) data) = (TYPE) floor (cur); \
data += sizeof (TYPE); \
} \
} \
}
#define CREATE_OPTIMIZED_FUNCTIONS(TYPE) \
typedef struct { \
TYPE x1, x2; /* history of input values for a filter */ \
TYPE y1, y2; /* history of output values for a filter */ \
} SecondOrderHistory ## TYPE; \
\
static inline TYPE \
one_step_ ## TYPE (GstIirEqualizerBand *filter, \
SecondOrderHistory ## TYPE *history, TYPE input) \
{ \
/* calculate output */ \
TYPE output = filter->a0 * input + filter->a1 * history->x1 + \
filter->a2 * history->x2 + filter->b1 * history->y1 + \
filter->b2 * history->y2; \
/* update history */ \
history->y2 = history->y1; \
history->y1 = output; \
history->x2 = history->x1; \
history->x1 = input; \
\
return output; \
} \
\
static const guint \
history_size_ ## TYPE = sizeof (SecondOrderHistory ## TYPE); \
\
static void \
gst_iir_equ_process_ ## TYPE (GstIirEqualizer *equ, guint8 *data, \
guint size, guint channels) \
{ \
guint frames = size / channels / sizeof (TYPE); \
guint i, c, f; \
TYPE cur; \
\
for (i = 0; i < frames; i++) { \
for (c = 0; c < channels; c++) { \
SecondOrderHistory ## TYPE *history = equ->history; \
cur = *((TYPE *) data); \
for (f = 0; f < equ->freq_band_count; f++) { \
GstIirEqualizerBand *filter = equ->bands[f]; \
\
cur = one_step_ ## TYPE (filter, history, cur); \
history++; \
} \
*((TYPE *) data) = (TYPE) cur; \
data += sizeof (TYPE); \
} \
} \
}
CREATE_OPTIMIZED_FUNCTIONS_INT (gint16, gfloat, -32768.0, 32767.0);
CREATE_OPTIMIZED_FUNCTIONS (gfloat);
CREATE_OPTIMIZED_FUNCTIONS (gdouble);
static GstFlowReturn
gst_iir_equalizer_transform_ip (GstBaseTransform * btrans, GstBuffer * buf)
{
GstAudioFilter *filter = GST_AUDIO_FILTER (btrans);
GstIirEqualizer *equ = GST_IIR_EQUALIZER (btrans);
GstClockTime timestamp;
if (G_UNLIKELY (filter->format.channels < 1 || equ->process == NULL))
return GST_FLOW_NOT_NEGOTIATED;
if (equ->need_new_coefficients) {
update_coefficients (equ);
set_passthrough (equ);
}
if (gst_base_transform_is_passthrough (btrans))
return GST_FLOW_OK;
timestamp = GST_BUFFER_TIMESTAMP (buf);
timestamp =
gst_segment_to_stream_time (&btrans->segment, GST_FORMAT_TIME, timestamp);
if (GST_CLOCK_TIME_IS_VALID (timestamp))
gst_object_sync_values (G_OBJECT (equ), timestamp);
equ->process (equ, GST_BUFFER_DATA (buf), GST_BUFFER_SIZE (buf),
filter->format.channels);
return GST_FLOW_OK;
}
static gboolean
gst_iir_equalizer_setup (GstAudioFilter * audio, GstRingBufferSpec * fmt)
{
GstIirEqualizer *equ = GST_IIR_EQUALIZER (audio);
switch (fmt->type) {
case GST_BUFTYPE_LINEAR:
switch (fmt->width) {
case 16:
equ->history_size = history_size_gint16;
equ->process = gst_iir_equ_process_gint16;
break;
default:
return FALSE;
}
break;
case GST_BUFTYPE_FLOAT:
switch (fmt->width) {
case 32:
equ->history_size = history_size_gfloat;
equ->process = gst_iir_equ_process_gfloat;
break;
case 64:
equ->history_size = history_size_gdouble;
equ->process = gst_iir_equ_process_gdouble;
break;
default:
return FALSE;
}
break;
default:
return FALSE;
}
alloc_history (equ);
return TRUE;
}
static gboolean
plugin_init (GstPlugin * plugin)
{
GST_DEBUG_CATEGORY_INIT (equalizer_debug, "equalizer", 0, "equalizer");
if (!(gst_element_register (plugin, "equalizer-nbands", GST_RANK_NONE,
GST_TYPE_IIR_EQUALIZER_NBANDS)))
return FALSE;
if (!(gst_element_register (plugin, "equalizer-3bands", GST_RANK_NONE,
GST_TYPE_IIR_EQUALIZER_3BANDS)))
return FALSE;
if (!(gst_element_register (plugin, "equalizer-10bands", GST_RANK_NONE,
GST_TYPE_IIR_EQUALIZER_10BANDS)))
return FALSE;
return TRUE;
}
GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
GST_VERSION_MINOR,
"equalizer",
"GStreamer audio equalizers",
plugin_init, VERSION, GST_LICENSE, GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)