gst/audiofx/audiofirfilter.c - imx-gst-plugins-good - Git at Google

 /*
  * 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., 51 Franklin St, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  *
  */

 /**
  * SECTION:element-audiofirfilter
  *
  * audiofirfilter implements a generic audio <ulink url="http://en.wikipedia.org/wiki/Finite_impulse_response">FIR filter</ulink>. Before usage the
  * "kernel" property has to be set to the filter kernel that should be
  * used and the "latency" property has to be set to the latency (in samples)
  * that is introduced by the filter kernel. Setting a latency of n samples
  * will lead to the first n samples being dropped from the output and
  * n samples added to the end.
  *
  * The filter kernel describes the impulse response of the filter. To
  * calculate the frequency response of the filter you have to calculate
  * the Fourier Transform of the impulse response.
  *
  * To change the filter kernel whenever the sampling rate changes the
  * "rate-changed" signal can be used. This should be done for most
  * FIR filters as they're depending on the sampling rate.
  *
  * <refsect2>
  * <title>Example application</title>
  * <informalexample><programlisting language="C">
  * <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" parse="text" href="../../../../tests/examples/audiofx/firfilter-example.c" />
  * </programlisting></informalexample>
  * </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 "audiofirfilter.h"

 #include "gst/glib-compat-private.h"

 #define GST_CAT_DEFAULT gst_audio_fir_filter_debug
 GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);

 enum
 {
   SIGNAL_RATE_CHANGED,
   LAST_SIGNAL
 };

 enum
 {
   PROP_0,
   PROP_KERNEL,
   PROP_LATENCY
 };

 static guint gst_audio_fir_filter_signals[LAST_SIGNAL] = { 0, };

 #define gst_audio_fir_filter_parent_class parent_class
 G_DEFINE_TYPE (GstAudioFIRFilter, gst_audio_fir_filter,
     GST_TYPE_AUDIO_FX_BASE_FIR_FILTER);

 static void gst_audio_fir_filter_set_property (GObject * object, guint prop_id,
     const GValue * value, GParamSpec * pspec);
 static void gst_audio_fir_filter_get_property (GObject * object, guint prop_id,
     GValue * value, GParamSpec * pspec);
 static void gst_audio_fir_filter_finalize (GObject * object);

 static gboolean gst_audio_fir_filter_setup (GstAudioFilter * base,
     const GstAudioInfo * info);


 static void
 gst_audio_fir_filter_class_init (GstAudioFIRFilterClass * klass)
 {
   GObjectClass *gobject_class = (GObjectClass *) klass;
   GstElementClass *gstelement_class = (GstElementClass *) klass;
   GstAudioFilterClass *filter_class = (GstAudioFilterClass *) klass;

   GST_DEBUG_CATEGORY_INIT (gst_audio_fir_filter_debug, "audiofirfilter", 0,
       "Generic audio FIR filter plugin");

   gobject_class->set_property = gst_audio_fir_filter_set_property;
   gobject_class->get_property = gst_audio_fir_filter_get_property;
   gobject_class->finalize = gst_audio_fir_filter_finalize;

   g_object_class_install_property (gobject_class, PROP_KERNEL,
       g_param_spec_value_array ("kernel", "Filter Kernel",
           "Filter kernel for the FIR filter",
           g_param_spec_double ("Element", "Filter Kernel Element",
               "Element of the filter kernel", -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_LATENCY,
       g_param_spec_uint64 ("latency", "Latecy",
           "Filter latency in samples",
           0, G_MAXUINT64, 0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   filter_class->setup = GST_DEBUG_FUNCPTR (gst_audio_fir_filter_setup);

   /**
    * GstAudioFIRFilter::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_fir_filter_signals[SIGNAL_RATE_CHANGED] =
       g_signal_new ("rate-changed", G_TYPE_FROM_CLASS (klass),
       G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstAudioFIRFilterClass, rate_changed),
       NULL, NULL, NULL, G_TYPE_NONE, 1, G_TYPE_INT);

   gst_element_class_set_static_metadata (gstelement_class,
       "Audio FIR filter", "Filter/Effect/Audio",
       "Generic audio FIR filter with custom filter kernel",
       "Sebastian Dröge <sebastian.droege@collabora.co.uk>");
 }

 static void
 gst_audio_fir_filter_update_kernel (GstAudioFIRFilter * self, GValueArray * va)
 {
   gdouble *kernel;
   guint i;

   if (va) {
     if (self->kernel)
       g_value_array_free (self->kernel);

     self->kernel = va;
   }

   kernel = g_new (gdouble, self->kernel->n_values);

   for (i = 0; i < self->kernel->n_values; i++) {
     GValue *v = g_value_array_get_nth (self->kernel, i);
     kernel[i] = g_value_get_double (v);
   }

   gst_audio_fx_base_fir_filter_set_kernel (GST_AUDIO_FX_BASE_FIR_FILTER (self),
       kernel, self->kernel->n_values, self->latency, NULL);
 }

 static void
 gst_audio_fir_filter_init (GstAudioFIRFilter * self)
 {
   GValue v = { 0, };
   GValueArray *va;

   self->latency = 0;
   va = g_value_array_new (1);

   g_value_init (&v, G_TYPE_DOUBLE);
   g_value_set_double (&v, 1.0);
   g_value_array_append (va, &v);
   g_value_unset (&v);
   gst_audio_fir_filter_update_kernel (self, va);

   g_mutex_init (&self->lock);
 }

 /* GstAudioFilter vmethod implementations */

 /* get notified of caps and plug in the correct process function */
 static gboolean
 gst_audio_fir_filter_setup (GstAudioFilter * base, const GstAudioInfo * info)
 {
   GstAudioFIRFilter *self = GST_AUDIO_FIR_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_fir_filter_signals[SIGNAL_RATE_CHANGED], 0, new_rate);
   }

   return GST_AUDIO_FILTER_CLASS (parent_class)->setup (base, info);
 }

 static void
 gst_audio_fir_filter_finalize (GObject * object)
 {
   GstAudioFIRFilter *self = GST_AUDIO_FIR_FILTER (object);

   g_mutex_clear (&self->lock);

   if (self->kernel)
     g_value_array_free (self->kernel);
   self->kernel = NULL;

   G_OBJECT_CLASS (parent_class)->finalize (object);
 }

 static void
 gst_audio_fir_filter_set_property (GObject * object, guint prop_id,
     const GValue * value, GParamSpec * pspec)
 {
   GstAudioFIRFilter *self = GST_AUDIO_FIR_FILTER (object);

   g_return_if_fail (GST_IS_AUDIO_FIR_FILTER (self));

   switch (prop_id) {
     case PROP_KERNEL:
       g_mutex_lock (&self->lock);
       /* update kernel already pushes residues */
       gst_audio_fir_filter_update_kernel (self, g_value_dup_boxed (value));
       g_mutex_unlock (&self->lock);
       break;
     case PROP_LATENCY:
       g_mutex_lock (&self->lock);
       self->latency = g_value_get_uint64 (value);
       gst_audio_fir_filter_update_kernel (self, NULL);
       g_mutex_unlock (&self->lock);
       break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
   }
 }

 static void
 gst_audio_fir_filter_get_property (GObject * object, guint prop_id,
     GValue * value, GParamSpec * pspec)
 {
   GstAudioFIRFilter *self = GST_AUDIO_FIR_FILTER (object);

   switch (prop_id) {
     case PROP_KERNEL:
       g_value_set_boxed (value, self->kernel);
       break;
     case PROP_LATENCY:
       g_value_set_uint64 (value, self->latency);
       break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
   }
 }
	/*
	* 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., 51 Franklin St, Fifth Floor,
	* Boston, MA 02110-1301, USA.
	*
	*/

	/**
	* SECTION:element-audiofirfilter
	*
	* audiofirfilter implements a generic audio <ulink url="http://en.wikipedia.org/wiki/Finite_impulse_response">FIR filter</ulink>. Before usage the
	* "kernel" property has to be set to the filter kernel that should be
	* used and the "latency" property has to be set to the latency (in samples)
	* that is introduced by the filter kernel. Setting a latency of n samples
	* will lead to the first n samples being dropped from the output and
	* n samples added to the end.
	*
	* The filter kernel describes the impulse response of the filter. To
	* calculate the frequency response of the filter you have to calculate
	* the Fourier Transform of the impulse response.
	*
	* To change the filter kernel whenever the sampling rate changes the
	* "rate-changed" signal can be used. This should be done for most
	* FIR filters as they're depending on the sampling rate.
	*
	* <refsect2>
	* <title>Example application</title>
	* <informalexample><programlisting language="C">
	* <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" parse="text" href="../../../../tests/examples/audiofx/firfilter-example.c" />
	* </programlisting></informalexample>
	* </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 "audiofirfilter.h"

	#include "gst/glib-compat-private.h"

	#define GST_CAT_DEFAULT gst_audio_fir_filter_debug
	GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);

	enum
	{
	SIGNAL_RATE_CHANGED,
	LAST_SIGNAL
	};

	enum
	{
	PROP_0,
	PROP_KERNEL,
	PROP_LATENCY
	};

	static guint gst_audio_fir_filter_signals[LAST_SIGNAL] = { 0, };

	#define gst_audio_fir_filter_parent_class parent_class
	G_DEFINE_TYPE (GstAudioFIRFilter, gst_audio_fir_filter,
	GST_TYPE_AUDIO_FX_BASE_FIR_FILTER);

	static void gst_audio_fir_filter_set_property (GObject * object, guint prop_id,
	const GValue * value, GParamSpec * pspec);
	static void gst_audio_fir_filter_get_property (GObject * object, guint prop_id,
	GValue * value, GParamSpec * pspec);
	static void gst_audio_fir_filter_finalize (GObject * object);

	static gboolean gst_audio_fir_filter_setup (GstAudioFilter * base,
	const GstAudioInfo * info);


	static void
	gst_audio_fir_filter_class_init (GstAudioFIRFilterClass * klass)
	{
	GObjectClass gobject_class = (GObjectClass ) klass;
	GstElementClass gstelement_class = (GstElementClass ) klass;
	GstAudioFilterClass filter_class = (GstAudioFilterClass ) klass;

	GST_DEBUG_CATEGORY_INIT (gst_audio_fir_filter_debug, "audiofirfilter", 0,
	"Generic audio FIR filter plugin");

	gobject_class->set_property = gst_audio_fir_filter_set_property;
	gobject_class->get_property = gst_audio_fir_filter_get_property;
	gobject_class->finalize = gst_audio_fir_filter_finalize;

	g_object_class_install_property (gobject_class, PROP_KERNEL,
	g_param_spec_value_array ("kernel", "Filter Kernel",
	"Filter kernel for the FIR filter",
	g_param_spec_double ("Element", "Filter Kernel Element",
	"Element of the filter kernel", -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_LATENCY,
	g_param_spec_uint64 ("latency", "Latecy",
	"Filter latency in samples",
	0, G_MAXUINT64, 0, G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	filter_class->setup = GST_DEBUG_FUNCPTR (gst_audio_fir_filter_setup);

	/**
	* GstAudioFIRFilter::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_fir_filter_signals[SIGNAL_RATE_CHANGED] =
	g_signal_new ("rate-changed", G_TYPE_FROM_CLASS (klass),
	G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstAudioFIRFilterClass, rate_changed),
	NULL, NULL, NULL, G_TYPE_NONE, 1, G_TYPE_INT);

	gst_element_class_set_static_metadata (gstelement_class,
	"Audio FIR filter", "Filter/Effect/Audio",
	"Generic audio FIR filter with custom filter kernel",
	"Sebastian Dröge <sebastian.droege@collabora.co.uk>");
	}

	static void
	gst_audio_fir_filter_update_kernel (GstAudioFIRFilter * self, GValueArray * va)
	{
	gdouble *kernel;
	guint i;

	if (va) {
	if (self->kernel)
	g_value_array_free (self->kernel);

	self->kernel = va;
	}

	kernel = g_new (gdouble, self->kernel->n_values);

	for (i = 0; i < self->kernel->n_values; i++) {
	GValue *v = g_value_array_get_nth (self->kernel, i);
	kernel[i] = g_value_get_double (v);
	}

	gst_audio_fx_base_fir_filter_set_kernel (GST_AUDIO_FX_BASE_FIR_FILTER (self),
	kernel, self->kernel->n_values, self->latency, NULL);
	}

	static void
	gst_audio_fir_filter_init (GstAudioFIRFilter * self)
	{
	GValue v = { 0, };
	GValueArray *va;

	self->latency = 0;
	va = g_value_array_new (1);

	g_value_init (&v, G_TYPE_DOUBLE);
	g_value_set_double (&v, 1.0);
	g_value_array_append (va, &v);
	g_value_unset (&v);
	gst_audio_fir_filter_update_kernel (self, va);

	g_mutex_init (&self->lock);
	}

	/* GstAudioFilter vmethod implementations */

	/* get notified of caps and plug in the correct process function */
	static gboolean
	gst_audio_fir_filter_setup (GstAudioFilter * base, const GstAudioInfo * info)
	{
	GstAudioFIRFilter *self = GST_AUDIO_FIR_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_fir_filter_signals[SIGNAL_RATE_CHANGED], 0, new_rate);
	}

	return GST_AUDIO_FILTER_CLASS (parent_class)->setup (base, info);
	}

	static void
	gst_audio_fir_filter_finalize (GObject * object)
	{
	GstAudioFIRFilter *self = GST_AUDIO_FIR_FILTER (object);

	g_mutex_clear (&self->lock);

	if (self->kernel)
	g_value_array_free (self->kernel);
	self->kernel = NULL;

	G_OBJECT_CLASS (parent_class)->finalize (object);
	}

	static void
	gst_audio_fir_filter_set_property (GObject * object, guint prop_id,
	const GValue * value, GParamSpec * pspec)
	{
	GstAudioFIRFilter *self = GST_AUDIO_FIR_FILTER (object);

	g_return_if_fail (GST_IS_AUDIO_FIR_FILTER (self));

	switch (prop_id) {
	case PROP_KERNEL:
	g_mutex_lock (&self->lock);
	/* update kernel already pushes residues */
	gst_audio_fir_filter_update_kernel (self, g_value_dup_boxed (value));
	g_mutex_unlock (&self->lock);
	break;
	case PROP_LATENCY:
	g_mutex_lock (&self->lock);
	self->latency = g_value_get_uint64 (value);
	gst_audio_fir_filter_update_kernel (self, NULL);
	g_mutex_unlock (&self->lock);
	break;
	default:
	G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
	break;
	}
	}

	static void
	gst_audio_fir_filter_get_property (GObject * object, guint prop_id,
	GValue * value, GParamSpec * pspec)
	{
	GstAudioFIRFilter *self = GST_AUDIO_FIR_FILTER (object);

	switch (prop_id) {
	case PROP_KERNEL:
	g_value_set_boxed (value, self->kernel);
	break;
	case PROP_LATENCY:
	g_value_set_uint64 (value, self->latency);
	break;
	default:
	G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
	break;
	}
	}