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/* GStreamer
* Copyright (C) <2004> Benjamin Otte <otte@gnome.org>
* <2007> Stefan Kost <ensonic@users.sf.net>
*
* 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-equalizer-nbands
*
* The n-band equalizer element is a fully parametric equalizer. It allows to
* select between 1 and 64 bands and has properties on each band to change
* the center frequency, band width and gain.
*
* <refsect2>
* <title>Example launch line</title>
* |[
* gst-launch filesrc location=song.ogg ! oggdemux ! vorbisdec ! audioconvert ! equalizer-nbands num-bands=15 band5::gain=6.0 ! alsasink
* ]| This make the equalizer use 15 bands and raises the volume of the 5th band by 6 db.
* </refsect2>
* <refsect2>
* <title>Example code</title>
* |[
* #include <gst/gst.h>
*
* ...
* typedef struct {
* gfloat freq;
* gfloat width;
* gfloat gain;
* } GstEqualizerBandState;
*
* ...
*
* GstElement *equalizer;
* GstObject *band;
* gint i;
* GstEqualizerBandState state[] = {
* { 120.0, 50.0, - 3.0},
* { 500.0, 20.0, 12.0},
* {1503.0, 2.0, -20.0},
* {6000.0, 1000.0, 6.0},
* {3000.0, 120.0, 2.0}
* };
*
* ...
*
* equalizer = gst_element_factory_make ("equalizer-nbands", "equalizer");
* g_object_set (G_OBJECT (equalizer), "num-bands", 5, NULL);
*
* ...
*
* for (i = 0; i < 5; i++) {
* band = gst_child_proxy_get_child_by_index (GST_CHILD_PROXY (equalizer), i);
* g_object_set (G_OBJECT (band), "freq", state[i].freq,
* "bandwidth", state[i].width,
* "gain", state[i].gain);
* g_object_unref (G_OBJECT (band));
* }
*
* ...
* ]|
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "gstiirequalizer.h"
#include "gstiirequalizernbands.h"
enum
{
PROP_NUM_BANDS = 1
};
static void gst_iir_equalizer_nbands_set_property (GObject * object,
guint prop_id, const GValue * value, GParamSpec * pspec);
static void gst_iir_equalizer_nbands_get_property (GObject * object,
guint prop_id, GValue * value, GParamSpec * pspec);
GST_DEBUG_CATEGORY_EXTERN (equalizer_debug);
#define GST_CAT_DEFAULT equalizer_debug
#define gst_iir_equalizer_nbands_parent_class parent_class
G_DEFINE_TYPE (GstIirEqualizerNBands, gst_iir_equalizer_nbands,
GST_TYPE_IIR_EQUALIZER);
/* equalizer implementation */
static void
gst_iir_equalizer_nbands_class_init (GstIirEqualizerNBandsClass * klass)
{
GObjectClass *gobject_class = (GObjectClass *) klass;
GstElementClass *gstelement_class = (GstElementClass *) klass;
gobject_class->set_property = gst_iir_equalizer_nbands_set_property;
gobject_class->get_property = gst_iir_equalizer_nbands_get_property;
g_object_class_install_property (gobject_class, PROP_NUM_BANDS,
g_param_spec_uint ("num-bands", "num-bands",
"number of different bands to use", 1, 64, 10,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_CONSTRUCT));
gst_element_class_set_static_metadata (gstelement_class, "N Band Equalizer",
"Filter/Effect/Audio",
"Direct Form IIR equalizer",
"Benjamin Otte <otte@gnome.org>," " Stefan Kost <ensonic@users.sf.net>");
}
static void
gst_iir_equalizer_nbands_init (GstIirEqualizerNBands * equ_n)
{
GstIirEqualizer *equ = GST_IIR_EQUALIZER (equ_n);
gst_iir_equalizer_compute_frequencies (equ, 10);
}
static void
gst_iir_equalizer_nbands_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstIirEqualizer *equ = GST_IIR_EQUALIZER (object);
switch (prop_id) {
case PROP_NUM_BANDS:
gst_iir_equalizer_compute_frequencies (equ, g_value_get_uint (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_iir_equalizer_nbands_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstIirEqualizer *equ = GST_IIR_EQUALIZER (object);
switch (prop_id) {
case PROP_NUM_BANDS:
g_value_set_uint (value, equ->freq_band_count);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
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