gst/audiofx/: Implement a base class for IIR filters.
Original commit message from CVS:
* gst/audiofx/Makefile.am:
* gst/audiofx/audiofxbaseiirfilter.c:
(gst_audio_fx_base_iir_filter_base_init),
(gst_audio_fx_base_iir_filter_dispose),
(gst_audio_fx_base_iir_filter_class_init),
(gst_audio_fx_base_iir_filter_init),
(gst_audio_fx_base_iir_filter_calculate_gain),
(gst_audio_fx_base_iir_filter_set_coefficients),
(gst_audio_fx_base_iir_filter_setup), (process),
(gst_audio_fx_base_iir_filter_transform_ip),
(gst_audio_fx_base_iir_filter_stop):
* gst/audiofx/audiofxbaseiirfilter.h:
Implement a base class for IIR filters.
* gst/audiofx/audiochebband.c: (gst_audio_cheb_band_base_init),
(gst_audio_cheb_band_class_init), (gst_audio_cheb_band_init),
(generate_coefficients), (gst_audio_cheb_band_set_property),
(gst_audio_cheb_band_setup):
* gst/audiofx/audiochebband.h:
* gst/audiofx/audiocheblimit.c: (gst_audio_cheb_limit_base_init),
(gst_audio_cheb_limit_class_init), (gst_audio_cheb_limit_init),
(generate_coefficients), (gst_audio_cheb_limit_set_property),
(gst_audio_cheb_limit_setup):
* gst/audiofx/audiocheblimit.h:
Use the IIR filter base class for the chebyshev filters.
2009-01-05 10:13:29 +00:00
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/*
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* GStreamer
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* Copyright (C) 2007-2009 Sebastian Dröge <sebastian.droege@collabora.co.uk>
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Library General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Library General Public License for more details.
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*
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* You should have received a copy of the GNU Library General Public
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* License along with this library; if not, write to the
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* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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* Boston, MA 02111-1307, USA.
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*/
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#ifdef HAVE_CONFIG_H
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#include "config.h"
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#endif
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#include <gst/gst.h>
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#include <gst/base/gstbasetransform.h>
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#include <gst/audio/audio.h>
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#include <gst/audio/gstaudiofilter.h>
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#include <gst/controller/gstcontroller.h>
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#include <math.h>
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#include "audiofxbaseiirfilter.h"
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#define GST_CAT_DEFAULT gst_audio_fx_base_iir_filter_debug
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GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
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#define ALLOWED_CAPS \
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"audio/x-raw-float," \
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" width = (int) { 32, 64 }, " \
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" endianness = (int) BYTE_ORDER," \
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" rate = (int) [ 1, MAX ]," \
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" channels = (int) [ 1, MAX ]"
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#define DEBUG_INIT(bla) \
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gst/audiofx/: Implement a base class for generic audio FIR filters.
Original commit message from CVS:
* gst/audiofx/Makefile.am:
* gst/audiofx/audiofxbasefirfilter.c:
(gst_audio_fx_base_fir_filter_dispose),
(gst_audio_fx_base_fir_filter_base_init),
(gst_audio_fx_base_fir_filter_class_init),
(gst_audio_fx_base_fir_filter_init),
(gst_audio_fx_base_fir_filter_push_residue),
(gst_audio_fx_base_fir_filter_setup),
(gst_audio_fx_base_fir_filter_transform),
(gst_audio_fx_base_fir_filter_start),
(gst_audio_fx_base_fir_filter_stop),
(gst_audio_fx_base_fir_filter_query),
(gst_audio_fx_base_fir_filter_query_type),
(gst_audio_fx_base_fir_filter_event),
(gst_audio_fx_base_fir_filter_set_kernel):
* gst/audiofx/audiofxbasefirfilter.h:
* gst/audiofx/audiofxbaseiirfilter.c:
Implement a base class for generic audio FIR filters.
* gst/audiofx/audiowsincband.c:
(gst_gst_audio_wsincband_mode_get_type),
(gst_gst_audio_wsincband_window_get_type),
(gst_audio_wsincband_base_init), (gst_audio_wsincband_class_init),
(gst_audio_wsincband_init), (gst_audio_wsincband_build_kernel),
(gst_audio_wsincband_setup), (gst_audio_wsincband_set_property),
(gst_audio_wsincband_get_property):
* gst/audiofx/audiowsincband.h:
* gst/audiofx/audiowsinclimit.c:
(gst_audio_wsinclimit_mode_get_type),
(gst_audio_wsinclimit_window_get_type),
(gst_audio_wsinclimit_base_init),
(gst_audio_wsinclimit_class_init), (gst_audio_wsinclimit_init),
(gst_audio_wsinclimit_build_kernel), (gst_audio_wsinclimit_setup),
(gst_audio_wsinclimit_set_property),
(gst_audio_wsinclimit_get_property):
* gst/audiofx/audiowsinclimit.h:
* tests/check/elements/audiowsincband.c: (GST_START_TEST):
* tests/check/elements/audiowsinclimit.c: (GST_START_TEST):
Use this new base class for audiowsincband and audiowsinclimit.
Also cleanup both elements.
2009-01-11 19:03:38 +00:00
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GST_DEBUG_CATEGORY_INIT (gst_audio_fx_base_iir_filter_debug, "audiofxbaseiirfilter", 0, "Audio IIR Filter Base Class");
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gst/audiofx/: Implement a base class for IIR filters.
Original commit message from CVS:
* gst/audiofx/Makefile.am:
* gst/audiofx/audiofxbaseiirfilter.c:
(gst_audio_fx_base_iir_filter_base_init),
(gst_audio_fx_base_iir_filter_dispose),
(gst_audio_fx_base_iir_filter_class_init),
(gst_audio_fx_base_iir_filter_init),
(gst_audio_fx_base_iir_filter_calculate_gain),
(gst_audio_fx_base_iir_filter_set_coefficients),
(gst_audio_fx_base_iir_filter_setup), (process),
(gst_audio_fx_base_iir_filter_transform_ip),
(gst_audio_fx_base_iir_filter_stop):
* gst/audiofx/audiofxbaseiirfilter.h:
Implement a base class for IIR filters.
* gst/audiofx/audiochebband.c: (gst_audio_cheb_band_base_init),
(gst_audio_cheb_band_class_init), (gst_audio_cheb_band_init),
(generate_coefficients), (gst_audio_cheb_band_set_property),
(gst_audio_cheb_band_setup):
* gst/audiofx/audiochebband.h:
* gst/audiofx/audiocheblimit.c: (gst_audio_cheb_limit_base_init),
(gst_audio_cheb_limit_class_init), (gst_audio_cheb_limit_init),
(generate_coefficients), (gst_audio_cheb_limit_set_property),
(gst_audio_cheb_limit_setup):
* gst/audiofx/audiocheblimit.h:
Use the IIR filter base class for the chebyshev filters.
2009-01-05 10:13:29 +00:00
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GST_BOILERPLATE_FULL (GstAudioFXBaseIIRFilter,
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gst_audio_fx_base_iir_filter, GstAudioFilter, GST_TYPE_AUDIO_FILTER,
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DEBUG_INIT);
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static gboolean gst_audio_fx_base_iir_filter_setup (GstAudioFilter * filter,
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GstRingBufferSpec * format);
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static GstFlowReturn
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gst_audio_fx_base_iir_filter_transform_ip (GstBaseTransform * base,
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GstBuffer * buf);
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static gboolean gst_audio_fx_base_iir_filter_stop (GstBaseTransform * base);
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static void process_64 (GstAudioFXBaseIIRFilter * filter,
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gdouble * data, guint num_samples);
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static void process_32 (GstAudioFXBaseIIRFilter * filter,
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gfloat * data, guint num_samples);
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/* GObject vmethod implementations */
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static void
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gst_audio_fx_base_iir_filter_base_init (gpointer klass)
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{
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GstCaps *caps;
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caps = gst_caps_from_string (ALLOWED_CAPS);
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gst_audio_filter_class_add_pad_templates (GST_AUDIO_FILTER_CLASS (klass),
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caps);
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gst_caps_unref (caps);
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}
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static void
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gst_audio_fx_base_iir_filter_dispose (GObject * object)
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{
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GstAudioFXBaseIIRFilter *filter = GST_AUDIO_FX_BASE_IIR_FILTER (object);
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if (filter->a) {
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g_free (filter->a);
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filter->a = NULL;
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}
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if (filter->b) {
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g_free (filter->b);
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filter->b = NULL;
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}
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if (filter->channels) {
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GstAudioFXBaseIIRFilterChannelCtx *ctx;
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guint i;
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for (i = 0; i < filter->nchannels; i++) {
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ctx = &filter->channels[i];
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g_free (ctx->x);
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g_free (ctx->y);
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}
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g_free (filter->channels);
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filter->channels = NULL;
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}
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G_OBJECT_CLASS (parent_class)->dispose (object);
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}
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static void
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gst_audio_fx_base_iir_filter_class_init (GstAudioFXBaseIIRFilterClass * klass)
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{
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GObjectClass *gobject_class = (GObjectClass *) klass;
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GstBaseTransformClass *trans_class = (GstBaseTransformClass *) klass;
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GstAudioFilterClass *filter_class = (GstAudioFilterClass *) klass;
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gobject_class->dispose = gst_audio_fx_base_iir_filter_dispose;
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filter_class->setup = GST_DEBUG_FUNCPTR (gst_audio_fx_base_iir_filter_setup);
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trans_class->transform_ip =
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GST_DEBUG_FUNCPTR (gst_audio_fx_base_iir_filter_transform_ip);
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trans_class->stop = GST_DEBUG_FUNCPTR (gst_audio_fx_base_iir_filter_stop);
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}
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static void
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gst_audio_fx_base_iir_filter_init (GstAudioFXBaseIIRFilter * filter,
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GstAudioFXBaseIIRFilterClass * klass)
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{
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gst_base_transform_set_in_place (GST_BASE_TRANSFORM (filter), TRUE);
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filter->a = NULL;
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filter->na = 0;
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filter->b = NULL;
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filter->nb = 0;
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filter->channels = NULL;
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filter->nchannels = 0;
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}
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/* Evaluate the transfer function that corresponds to the IIR
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* coefficients at zr + zi*I and return the magnitude */
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gdouble
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gst_audio_fx_base_iir_filter_calculate_gain (gdouble * a, guint na, gdouble * b,
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guint nb, gdouble zr, gdouble zi)
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{
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gdouble sum_ar, sum_ai;
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gdouble sum_br, sum_bi;
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gdouble gain_r, gain_i;
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gdouble sum_r_old;
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gdouble sum_i_old;
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gint i;
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sum_ar = 0.0;
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sum_ai = 0.0;
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for (i = na - 1; i >= 0; i--) {
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sum_r_old = sum_ar;
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sum_i_old = sum_ai;
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sum_ar = (sum_r_old * zr - sum_i_old * zi) + a[i];
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sum_ai = (sum_r_old * zi + sum_i_old * zr) + 0.0;
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}
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sum_br = 0.0;
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sum_bi = 0.0;
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for (i = nb - 1; i >= 0; i--) {
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sum_r_old = sum_br;
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sum_i_old = sum_bi;
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sum_br = (sum_r_old * zr - sum_i_old * zi) - b[i];
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sum_bi = (sum_r_old * zi + sum_i_old * zr) - 0.0;
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}
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sum_br += 1.0;
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sum_bi += 0.0;
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gain_r =
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(sum_ar * sum_br + sum_ai * sum_bi) / (sum_br * sum_br + sum_bi * sum_bi);
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gain_i =
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(sum_ai * sum_br - sum_ar * sum_bi) / (sum_br * sum_br + sum_bi * sum_bi);
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return (sqrt (gain_r * gain_r + gain_i * gain_i));
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}
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void
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gst_audio_fx_base_iir_filter_set_coefficients (GstAudioFXBaseIIRFilter * filter,
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gdouble * a, guint na, gdouble * b, guint nb)
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{
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guint i;
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g_return_if_fail (GST_IS_AUDIO_FX_BASE_IIR_FILTER (filter));
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GST_BASE_TRANSFORM_LOCK (filter);
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g_free (filter->a);
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g_free (filter->b);
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filter->a = filter->b = NULL;
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if (filter->channels) {
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GstAudioFXBaseIIRFilterChannelCtx *ctx;
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gboolean free = (na != filter->na || nb != filter->nb);
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for (i = 0; i < filter->nchannels; i++) {
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ctx = &filter->channels[i];
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if (free)
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g_free (ctx->x);
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else
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memset (ctx->x, 0, filter->na * sizeof (gdouble));
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if (free)
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g_free (ctx->y);
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else
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memset (ctx->y, 0, filter->nb * sizeof (gdouble));
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}
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g_free (filter->channels);
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filter->channels = NULL;
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}
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filter->na = na;
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filter->nb = nb;
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filter->a = a;
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filter->b = b;
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if (filter->nchannels && !filter->channels) {
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GstAudioFXBaseIIRFilterChannelCtx *ctx;
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filter->channels =
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g_new0 (GstAudioFXBaseIIRFilterChannelCtx, filter->nchannels);
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for (i = 0; i < filter->nchannels; i++) {
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ctx = &filter->channels[i];
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ctx->x = g_new0 (gdouble, filter->na);
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ctx->y = g_new0 (gdouble, filter->nb);
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}
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}
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GST_BASE_TRANSFORM_UNLOCK (filter);
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}
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/* GstAudioFilter vmethod implementations */
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static gboolean
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gst_audio_fx_base_iir_filter_setup (GstAudioFilter * base,
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GstRingBufferSpec * format)
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{
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GstAudioFXBaseIIRFilter *filter = GST_AUDIO_FX_BASE_IIR_FILTER (base);
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gboolean ret = TRUE;
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if (format->width == 32)
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filter->process = (GstAudioFXBaseIIRFilterProcessFunc)
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process_32;
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else if (format->width == 64)
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filter->process = (GstAudioFXBaseIIRFilterProcessFunc)
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process_64;
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else
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ret = FALSE;
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if (format->channels != filter->nchannels) {
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guint i;
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GstAudioFXBaseIIRFilterChannelCtx *ctx;
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if (filter->channels) {
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for (i = 0; i < filter->nchannels; i++) {
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ctx = &filter->channels[i];
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g_free (ctx->x);
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g_free (ctx->y);
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}
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g_free (filter->channels);
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filter->channels = NULL;
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}
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filter->nchannels = format->channels;
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filter->channels =
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g_new0 (GstAudioFXBaseIIRFilterChannelCtx, filter->nchannels);
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for (i = 0; i < filter->nchannels; i++) {
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ctx = &filter->channels[i];
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|
|
|
|
|
ctx->x = g_new0 (gdouble, filter->na);
|
|
|
|
ctx->y = g_new0 (gdouble, filter->nb);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline gdouble
|
|
|
|
process (GstAudioFXBaseIIRFilter * filter,
|
|
|
|
GstAudioFXBaseIIRFilterChannelCtx * ctx, gdouble x0)
|
|
|
|
{
|
|
|
|
gdouble val = filter->a[0] * x0;
|
|
|
|
gint i, j;
|
|
|
|
|
|
|
|
for (i = 1, j = ctx->x_pos; i < filter->na; i++) {
|
|
|
|
val += filter->a[i] * ctx->x[j];
|
|
|
|
j--;
|
|
|
|
if (j < 0)
|
|
|
|
j = filter->na - 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
for (i = 1, j = ctx->y_pos; i < filter->nb; i++) {
|
|
|
|
val += filter->b[i] * ctx->y[j];
|
|
|
|
j--;
|
|
|
|
if (j < 0)
|
|
|
|
j = filter->nb - 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (ctx->x) {
|
|
|
|
ctx->x_pos++;
|
|
|
|
if (ctx->x_pos >= filter->na)
|
|
|
|
ctx->x_pos = 0;
|
|
|
|
ctx->x[ctx->x_pos] = x0;
|
|
|
|
}
|
|
|
|
if (ctx->y) {
|
|
|
|
ctx->y_pos++;
|
|
|
|
if (ctx->y_pos >= filter->nb)
|
|
|
|
ctx->y_pos = 0;
|
|
|
|
|
|
|
|
ctx->y[ctx->y_pos] = val;
|
|
|
|
}
|
|
|
|
|
|
|
|
return val;
|
|
|
|
}
|
|
|
|
|
|
|
|
#define DEFINE_PROCESS_FUNC(width,ctype) \
|
|
|
|
static void \
|
|
|
|
process_##width (GstAudioFXBaseIIRFilter * filter, \
|
|
|
|
g##ctype * data, guint num_samples) \
|
|
|
|
{ \
|
|
|
|
gint i, j, channels = GST_AUDIO_FILTER (filter)->format.channels; \
|
|
|
|
gdouble val; \
|
|
|
|
\
|
|
|
|
for (i = 0; i < num_samples / channels; i++) { \
|
|
|
|
for (j = 0; j < channels; j++) { \
|
|
|
|
val = process (filter, &filter->channels[j], *data); \
|
|
|
|
*data++ = val; \
|
|
|
|
} \
|
|
|
|
} \
|
|
|
|
}
|
|
|
|
|
|
|
|
DEFINE_PROCESS_FUNC (32, float);
|
|
|
|
DEFINE_PROCESS_FUNC (64, double);
|
|
|
|
|
|
|
|
#undef DEFINE_PROCESS_FUNC
|
|
|
|
|
|
|
|
/* GstBaseTransform vmethod implementations */
|
|
|
|
static GstFlowReturn
|
|
|
|
gst_audio_fx_base_iir_filter_transform_ip (GstBaseTransform * base,
|
|
|
|
GstBuffer * buf)
|
|
|
|
{
|
|
|
|
GstAudioFXBaseIIRFilter *filter = GST_AUDIO_FX_BASE_IIR_FILTER (base);
|
|
|
|
guint num_samples =
|
|
|
|
GST_BUFFER_SIZE (buf) / (GST_AUDIO_FILTER (filter)->format.width / 8);
|
|
|
|
|
|
|
|
if (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_TIMESTAMP (buf)))
|
|
|
|
gst_object_sync_values (G_OBJECT (filter), GST_BUFFER_TIMESTAMP (buf));
|
|
|
|
|
|
|
|
if (gst_base_transform_is_passthrough (base))
|
|
|
|
return GST_FLOW_OK;
|
|
|
|
|
|
|
|
g_return_val_if_fail (filter->a != NULL, GST_FLOW_ERROR);
|
|
|
|
|
|
|
|
filter->process (filter, GST_BUFFER_DATA (buf), num_samples);
|
|
|
|
|
|
|
|
return GST_FLOW_OK;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
static gboolean
|
|
|
|
gst_audio_fx_base_iir_filter_stop (GstBaseTransform * base)
|
|
|
|
{
|
|
|
|
GstAudioFXBaseIIRFilter *filter = GST_AUDIO_FX_BASE_IIR_FILTER (base);
|
|
|
|
guint channels = GST_AUDIO_FILTER (filter)->format.channels;
|
|
|
|
GstAudioFXBaseIIRFilterChannelCtx *ctx;
|
|
|
|
guint i;
|
|
|
|
|
|
|
|
/* Reset the history of input and output values if
|
|
|
|
* already existing */
|
|
|
|
if (channels && filter->channels) {
|
|
|
|
for (i = 0; i < channels; i++) {
|
|
|
|
ctx = &filter->channels[i];
|
|
|
|
g_free (ctx->x);
|
|
|
|
g_free (ctx->y);
|
|
|
|
}
|
|
|
|
g_free (filter->channels);
|
|
|
|
}
|
|
|
|
filter->channels = NULL;
|
|
|
|
|
|
|
|
return TRUE;
|
|
|
|
}
|