--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/gst_plugins_good/gst/audiofx/audiowsincband.c Fri Apr 16 15:15:52 2010 +0300
@@ -0,0 +1,440 @@
+/* -*- c-basic-offset: 2 -*-
+ *
+ * GStreamer
+ * Copyright (C) 1999-2001 Erik Walthinsen <omega@cse.ogi.edu>
+ * 2006 Dreamlab Technologies Ltd. <mathis.hofer@dreamlab.net>
+ * 2007-2009 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.
+ *
+ *
+ * this windowed sinc filter is taken from the freely downloadable DSP book,
+ * "The Scientist and Engineer's Guide to Digital Signal Processing",
+ * chapter 16
+ * available at http://www.dspguide.com/
+ *
+ */
+
+/**
+ * SECTION:element-audiowsincband
+ *
+ * Attenuates all frequencies outside (bandpass) or inside (bandreject) of a frequency
+ * band. The length parameter controls the rolloff, the window parameter
+ * controls rolloff and stopband attenuation. The Hamming window provides a faster rolloff but a bit
+ * worse stopband attenuation, the other way around for the Blackman window.
+ *
+ * This element has the advantage over the Chebyshev bandpass and bandreject filter that it has
+ * a much better rolloff when using a larger kernel size and almost linear phase. The only
+ * disadvantage is the much slower execution time with larger kernels.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch audiotestsrc freq=1500 ! audioconvert ! audiosincband mode=band-pass lower-frequency=3000 upper-frequency=10000 length=501 window=blackman ! audioconvert ! alsasink
+ * gst-launch filesrc location="melo1.ogg" ! oggdemux ! vorbisdec ! audioconvert ! audiowsincband mode=band-reject lower-frequency=59 upper-frequency=61 length=10001 window=hamming ! audioconvert ! alsasink
+ * gst-launch audiotestsrc wave=white-noise ! audioconvert ! audiowsincband mode=band-pass lower-frequency=1000 upper-frequency=2000 length=31 ! audioconvert ! alsasink
+ * ]|
+ * </refsect2>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <string.h>
+#include <math.h>
+#include <gst/gst.h>
+#include <gst/audio/gstaudiofilter.h>
+#include <gst/controller/gstcontroller.h>
+
+#include "audiowsincband.h"
+
+#define GST_CAT_DEFAULT gst_gst_audio_wsincband_debug
+GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
+
+enum
+{
+ PROP_0,
+ PROP_LENGTH,
+ PROP_LOWER_FREQUENCY,
+ PROP_UPPER_FREQUENCY,
+ PROP_MODE,
+ PROP_WINDOW
+};
+
+enum
+{
+ MODE_BAND_PASS = 0,
+ MODE_BAND_REJECT
+};
+
+#define GST_TYPE_AUDIO_WSINC_BAND_MODE (gst_gst_audio_wsincband_mode_get_type ())
+static GType
+gst_gst_audio_wsincband_mode_get_type (void)
+{
+ static GType gtype = 0;
+
+ if (gtype == 0) {
+ static const GEnumValue values[] = {
+ {MODE_BAND_PASS, "Band pass (default)",
+ "band-pass"},
+ {MODE_BAND_REJECT, "Band reject",
+ "band-reject"},
+ {0, NULL, NULL}
+ };
+
+ gtype = g_enum_register_static ("GstAudioWSincBandMode", values);
+ }
+ return gtype;
+}
+
+enum
+{
+ WINDOW_HAMMING = 0,
+ WINDOW_BLACKMAN
+};
+
+#define GST_TYPE_AUDIO_WSINC_BAND_WINDOW (gst_gst_audio_wsincband_window_get_type ())
+static GType
+gst_gst_audio_wsincband_window_get_type (void)
+{
+ static GType gtype = 0;
+
+ if (gtype == 0) {
+ static const GEnumValue values[] = {
+ {WINDOW_HAMMING, "Hamming window (default)",
+ "hamming"},
+ {WINDOW_BLACKMAN, "Blackman window",
+ "blackman"},
+ {0, NULL, NULL}
+ };
+
+ gtype = g_enum_register_static ("GstAudioWSincBandWindow", values);
+ }
+ return gtype;
+}
+
+#define DEBUG_INIT(bla) \
+ GST_DEBUG_CATEGORY_INIT (gst_gst_audio_wsincband_debug, "audiowsincband", 0, \
+ "Band-pass and Band-reject Windowed sinc filter plugin");
+
+GST_BOILERPLATE_FULL (GstAudioWSincBand, gst_audio_wsincband, GstAudioFilter,
+ GST_TYPE_AUDIO_FX_BASE_FIR_FILTER, DEBUG_INIT);
+
+static void gst_audio_wsincband_set_property (GObject * object, guint prop_id,
+ const GValue * value, GParamSpec * pspec);
+static void gst_audio_wsincband_get_property (GObject * object, guint prop_id,
+ GValue * value, GParamSpec * pspec);
+static void gst_audio_wsincband_finalize (GObject * object);
+
+static gboolean gst_audio_wsincband_setup (GstAudioFilter * base,
+ GstRingBufferSpec * format);
+
+/* Element class */
+static void
+gst_audio_wsincband_base_init (gpointer g_class)
+{
+ GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
+
+ gst_element_class_set_details_simple (element_class,
+ "Band pass & band reject filter", "Filter/Effect/Audio",
+ "Band pass and band reject windowed sinc filter",
+ "Thomas Vander Stichele <thomas at apestaart dot org>, "
+ "Steven W. Smith, "
+ "Dreamlab Technologies Ltd. <mathis.hofer@dreamlab.net>, "
+ "Sebastian Dröge <sebastian.droege@collabora.co.uk>");
+}
+
+static void
+gst_audio_wsincband_class_init (GstAudioWSincBandClass * klass)
+{
+ GObjectClass *gobject_class = (GObjectClass *) klass;
+ GstAudioFilterClass *filter_class = (GstAudioFilterClass *) klass;
+
+ gobject_class->set_property = gst_audio_wsincband_set_property;
+ gobject_class->get_property = gst_audio_wsincband_get_property;
+ gobject_class->finalize = gst_audio_wsincband_finalize;
+
+ /* FIXME: Don't use the complete possible range but restrict the upper boundary
+ * so automatically generated UIs can use a slider */
+ g_object_class_install_property (gobject_class, PROP_LOWER_FREQUENCY,
+ g_param_spec_float ("lower-frequency", "Lower Frequency",
+ "Cut-off lower frequency (Hz)", 0.0, 100000.0, 0,
+ G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
+ g_object_class_install_property (gobject_class, PROP_UPPER_FREQUENCY,
+ g_param_spec_float ("upper-frequency", "Upper Frequency",
+ "Cut-off upper frequency (Hz)", 0.0, 100000.0, 0,
+ G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
+ g_object_class_install_property (gobject_class, PROP_LENGTH,
+ g_param_spec_int ("length", "Length",
+ "Filter kernel length, will be rounded to the next odd number", 3,
+ 50000, 101,
+ G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
+
+ g_object_class_install_property (gobject_class, PROP_MODE,
+ g_param_spec_enum ("mode", "Mode",
+ "Band pass or band reject mode", GST_TYPE_AUDIO_WSINC_BAND_MODE,
+ MODE_BAND_PASS,
+ G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
+
+ g_object_class_install_property (gobject_class, PROP_WINDOW,
+ g_param_spec_enum ("window", "Window",
+ "Window function to use", GST_TYPE_AUDIO_WSINC_BAND_WINDOW,
+ WINDOW_HAMMING,
+ G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
+
+ filter_class->setup = GST_DEBUG_FUNCPTR (gst_audio_wsincband_setup);
+}
+
+static void
+gst_audio_wsincband_init (GstAudioWSincBand * self,
+ GstAudioWSincBandClass * g_class)
+{
+ self->kernel_length = 101;
+ self->lower_frequency = 0.0;
+ self->upper_frequency = 0.0;
+ self->mode = MODE_BAND_PASS;
+ self->window = WINDOW_HAMMING;
+
+ self->lock = g_mutex_new ();
+}
+
+static void
+gst_audio_wsincband_build_kernel (GstAudioWSincBand * self)
+{
+ gint i = 0;
+ gdouble sum = 0.0;
+ gint len = 0;
+ gdouble *kernel_lp, *kernel_hp;
+ gdouble w;
+ gdouble *kernel;
+
+ len = self->kernel_length;
+
+ if (GST_AUDIO_FILTER (self)->format.rate == 0) {
+ GST_DEBUG ("rate not set yet");
+ return;
+ }
+
+ if (GST_AUDIO_FILTER (self)->format.channels == 0) {
+ GST_DEBUG ("channels not set yet");
+ return;
+ }
+
+ /* Clamp frequencies */
+ self->lower_frequency =
+ CLAMP (self->lower_frequency, 0.0,
+ GST_AUDIO_FILTER (self)->format.rate / 2);
+ self->upper_frequency =
+ CLAMP (self->upper_frequency, 0.0,
+ GST_AUDIO_FILTER (self)->format.rate / 2);
+ if (self->lower_frequency > self->upper_frequency) {
+ gint tmp = self->lower_frequency;
+
+ self->lower_frequency = self->upper_frequency;
+ self->upper_frequency = tmp;
+ }
+
+ GST_DEBUG ("gst_audio_wsincband: initializing filter kernel of length %d "
+ "with lower frequency %.2lf Hz "
+ ", upper frequency %.2lf Hz for mode %s",
+ len, self->lower_frequency, self->upper_frequency,
+ (self->mode == MODE_BAND_PASS) ? "band-pass" : "band-reject");
+
+ /* fill the lp kernel */
+ w = 2 * M_PI * (self->lower_frequency / GST_AUDIO_FILTER (self)->format.rate);
+ kernel_lp = g_new (gdouble, len);
+ for (i = 0; i < len; ++i) {
+ if (i == len / 2)
+ kernel_lp[i] = w;
+ else
+ kernel_lp[i] = sin (w * (i - len / 2))
+ / (i - len / 2);
+ /* Windowing */
+ if (self->window == WINDOW_HAMMING)
+ kernel_lp[i] *= (0.54 - 0.46 * cos (2 * M_PI * i / len));
+ else
+ kernel_lp[i] *=
+ (0.42 - 0.5 * cos (2 * M_PI * i / len) +
+ 0.08 * cos (4 * M_PI * i / len));
+ }
+
+ /* normalize for unity gain at DC */
+ sum = 0.0;
+ for (i = 0; i < len; ++i)
+ sum += kernel_lp[i];
+ for (i = 0; i < len; ++i)
+ kernel_lp[i] /= sum;
+
+ /* fill the hp kernel */
+ w = 2 * M_PI * (self->upper_frequency / GST_AUDIO_FILTER (self)->format.rate);
+ kernel_hp = g_new (gdouble, len);
+ for (i = 0; i < len; ++i) {
+ if (i == len / 2)
+ kernel_hp[i] = w;
+ else
+ kernel_hp[i] = sin (w * (i - len / 2))
+ / (i - len / 2);
+ /* Windowing */
+ if (self->window == WINDOW_HAMMING)
+ kernel_hp[i] *= (0.54 - 0.46 * cos (2 * M_PI * i / len));
+ else
+ kernel_hp[i] *=
+ (0.42 - 0.5 * cos (2 * M_PI * i / len) +
+ 0.08 * cos (4 * M_PI * i / len));
+ }
+
+ /* normalize for unity gain at DC */
+ sum = 0.0;
+ for (i = 0; i < len; ++i)
+ sum += kernel_hp[i];
+ for (i = 0; i < len; ++i)
+ kernel_hp[i] /= sum;
+
+ /* do spectral inversion to go from lowpass to highpass */
+ for (i = 0; i < len; ++i)
+ kernel_hp[i] = -kernel_hp[i];
+ kernel_hp[len / 2] += 1;
+
+ /* combine the two kernels */
+ kernel = g_new (gdouble, len);
+
+ for (i = 0; i < len; ++i)
+ kernel[i] = kernel_lp[i] + kernel_hp[i];
+
+ /* free the helper kernels */
+ g_free (kernel_lp);
+ g_free (kernel_hp);
+
+ /* do spectral inversion to go from bandreject to bandpass
+ * if specified */
+ if (self->mode == MODE_BAND_PASS) {
+ for (i = 0; i < len; ++i)
+ kernel[i] = -kernel[i];
+ kernel[len / 2] += 1;
+ }
+
+ gst_audio_fx_base_fir_filter_set_kernel (GST_AUDIO_FX_BASE_FIR_FILTER (self),
+ kernel, self->kernel_length, (len - 1) / 2);
+}
+
+/* GstAudioFilter vmethod implementations */
+
+/* get notified of caps and plug in the correct process function */
+static gboolean
+gst_audio_wsincband_setup (GstAudioFilter * base, GstRingBufferSpec * format)
+{
+ GstAudioWSincBand *self = GST_AUDIO_WSINC_BAND (base);
+
+ gst_audio_wsincband_build_kernel (self);
+
+ return GST_AUDIO_FILTER_CLASS (parent_class)->setup (base, format);
+}
+
+static void
+gst_audio_wsincband_finalize (GObject * object)
+{
+ GstAudioWSincBand *self = GST_AUDIO_WSINC_BAND (object);
+
+ g_mutex_free (self->lock);
+ self->lock = NULL;
+
+ G_OBJECT_CLASS (parent_class)->finalize (object);
+}
+
+static void
+gst_audio_wsincband_set_property (GObject * object, guint prop_id,
+ const GValue * value, GParamSpec * pspec)
+{
+ GstAudioWSincBand *self = GST_AUDIO_WSINC_BAND (object);
+
+ g_return_if_fail (GST_IS_AUDIO_WSINC_BAND (self));
+
+ switch (prop_id) {
+ case PROP_LENGTH:{
+ gint val;
+
+ g_mutex_lock (self->lock);
+ val = g_value_get_int (value);
+ if (val % 2 == 0)
+ val++;
+
+ if (val != self->kernel_length) {
+ gst_audio_fx_base_fir_filter_push_residue (GST_AUDIO_FX_BASE_FIR_FILTER
+ (self));
+ self->kernel_length = val;
+ gst_audio_wsincband_build_kernel (self);
+ }
+ g_mutex_unlock (self->lock);
+ break;
+ }
+ case PROP_LOWER_FREQUENCY:
+ g_mutex_lock (self->lock);
+ self->lower_frequency = g_value_get_float (value);
+ gst_audio_wsincband_build_kernel (self);
+ g_mutex_unlock (self->lock);
+ break;
+ case PROP_UPPER_FREQUENCY:
+ g_mutex_lock (self->lock);
+ self->upper_frequency = g_value_get_float (value);
+ gst_audio_wsincband_build_kernel (self);
+ g_mutex_unlock (self->lock);
+ break;
+ case PROP_MODE:
+ g_mutex_lock (self->lock);
+ self->mode = g_value_get_enum (value);
+ gst_audio_wsincband_build_kernel (self);
+ g_mutex_unlock (self->lock);
+ break;
+ case PROP_WINDOW:
+ g_mutex_lock (self->lock);
+ self->window = g_value_get_enum (value);
+ gst_audio_wsincband_build_kernel (self);
+ g_mutex_unlock (self->lock);
+ break;
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+ break;
+ }
+}
+
+static void
+gst_audio_wsincband_get_property (GObject * object, guint prop_id,
+ GValue * value, GParamSpec * pspec)
+{
+ GstAudioWSincBand *self = GST_AUDIO_WSINC_BAND (object);
+
+ switch (prop_id) {
+ case PROP_LENGTH:
+ g_value_set_int (value, self->kernel_length);
+ break;
+ case PROP_LOWER_FREQUENCY:
+ g_value_set_float (value, self->lower_frequency);
+ break;
+ case PROP_UPPER_FREQUENCY:
+ g_value_set_float (value, self->upper_frequency);
+ break;
+ case PROP_MODE:
+ g_value_set_enum (value, self->mode);
+ break;
+ case PROP_WINDOW:
+ g_value_set_enum (value, self->window);
+ break;
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+ break;
+ }
+}