gstreamer/libs/gst/controller/gstlfocontrolsource.c

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/* GStreamer
*
* Copyright (C) 2007,2010 Sebastian Dröge <sebastian.droege@collabora.co.uk>
*
* gstlfocontrolsource.c: Control source that provides some periodic waveforms
* as control values.
*
* 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:gstlfocontrolsource
* @title: GstLFOControlSource
* @short_description: LFO control source
*
* #GstLFOControlSource is a #GstControlSource, that provides several periodic
* waveforms as control values.
*
* To use #GstLFOControlSource get a new instance by calling
* gst_lfo_control_source_new(), bind it to a #GParamSpec and set the relevant
* properties.
*
* All functions are MT-safe.
*/
#include <float.h>
#include <glib-object.h>
#include <gst/gst.h>
#include <gst/gstcontrolsource.h>
#include "gstlfocontrolsource.h"
#include "gst/glib-compat-private.h"
#include <gst/math-compat.h>
#define GST_CAT_DEFAULT controller_debug
GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
struct _GstLFOControlSourcePrivate
{
GstLFOWaveform waveform;
gdouble frequency;
GstClockTime period;
GstClockTime timeshift;
gdouble amplitude;
gdouble offset;
};
/* FIXME: as % in C is not the modulo operator we need here for
* negative numbers implement our own. Are there better ways? */
static inline GstClockTime
_calculate_pos (GstClockTime timestamp, GstClockTime timeshift,
GstClockTime period)
{
while (timestamp < timeshift)
timestamp += period;
timestamp -= timeshift;
return timestamp % period;
}
static inline gdouble
_sine_get (GstLFOControlSource * self, gdouble amp, gdouble off,
GstClockTime timeshift, GstClockTime period, gdouble frequency,
GstClockTime timestamp)
{
gdouble pos =
gst_guint64_to_gdouble (_calculate_pos (timestamp, timeshift, period));
gdouble ret;
ret = sin (2.0 * M_PI * (frequency / GST_SECOND) * pos);
ret *= amp;
ret += off;
return ret;
}
static gboolean
waveform_sine_get (GstLFOControlSource * self, GstClockTime timestamp,
gdouble * value)
{
GstLFOControlSourcePrivate *priv = self->priv;
gst_object_sync_values (GST_OBJECT (self), timestamp);
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g_mutex_lock (&self->lock);
*value = _sine_get (self, priv->amplitude, priv->offset, priv->timeshift,
priv->period, priv->frequency, timestamp);
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g_mutex_unlock (&self->lock);
return TRUE;
}
static gboolean
waveform_sine_get_value_array (GstLFOControlSource * self,
GstClockTime timestamp, GstClockTime interval, guint n_values,
gdouble * values)
{
GstLFOControlSourcePrivate *priv = self->priv;
guint i;
GstClockTime ts = timestamp;
for (i = 0; i < n_values; i++) {
gst_object_sync_values (GST_OBJECT (self), ts);
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g_mutex_lock (&self->lock);
*values = _sine_get (self, priv->amplitude, priv->offset, priv->timeshift,
priv->period, priv->frequency, ts);
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g_mutex_unlock (&self->lock);
ts += interval;
values++;
}
return TRUE;
}
static inline gdouble
_square_get (GstLFOControlSource * self, gdouble amp, gdouble off,
GstClockTime timeshift, GstClockTime period, gdouble frequency,
GstClockTime timestamp)
{
GstClockTime pos = _calculate_pos (timestamp, timeshift, period);
gdouble ret;
if (pos >= period / 2)
ret = amp;
else
ret = -amp;
ret += off;
return ret;
}
static gboolean
waveform_square_get (GstLFOControlSource * self, GstClockTime timestamp,
gdouble * value)
{
GstLFOControlSourcePrivate *priv = self->priv;
gst_object_sync_values (GST_OBJECT (self), timestamp);
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g_mutex_lock (&self->lock);
*value = _square_get (self, priv->amplitude, priv->offset, priv->timeshift,
priv->period, priv->frequency, timestamp);
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g_mutex_unlock (&self->lock);
return TRUE;
}
static gboolean
waveform_square_get_value_array (GstLFOControlSource * self,
GstClockTime timestamp, GstClockTime interval, guint n_values,
gdouble * values)
{
GstLFOControlSourcePrivate *priv = self->priv;
guint i;
GstClockTime ts = timestamp;
for (i = 0; i < n_values; i++) {
gst_object_sync_values (GST_OBJECT (self), ts);
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g_mutex_lock (&self->lock);
*values = _square_get (self, priv->amplitude, priv->offset, priv->timeshift,
priv->period, priv->frequency, ts);
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g_mutex_unlock (&self->lock);
ts += interval;
values++;
}
return TRUE;
}
static inline gdouble
_saw_get (GstLFOControlSource * self, gdouble amp, gdouble off,
GstClockTime timeshift, GstClockTime period, gdouble frequency,
GstClockTime timestamp)
{
gdouble pos =
gst_guint64_to_gdouble (_calculate_pos (timestamp, timeshift, period));
gdouble per = gst_guint64_to_gdouble (period);
gdouble ret;
ret = -((pos - per / 2.0) * ((2.0 * amp) / per));
ret += off;
return ret;
}
static gboolean
waveform_saw_get (GstLFOControlSource * self, GstClockTime timestamp,
gdouble * value)
{
GstLFOControlSourcePrivate *priv = self->priv;
gst_object_sync_values (GST_OBJECT (self), timestamp);
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g_mutex_lock (&self->lock);
*value = _saw_get (self, priv->amplitude, priv->offset, priv->timeshift,
priv->period, priv->frequency, timestamp);
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g_mutex_unlock (&self->lock);
return TRUE;
}
static gboolean
waveform_saw_get_value_array (GstLFOControlSource * self,
GstClockTime timestamp, GstClockTime interval, guint n_values,
gdouble * values)
{
GstLFOControlSourcePrivate *priv = self->priv;
guint i;
GstClockTime ts = timestamp;
for (i = 0; i < n_values; i++) {
gst_object_sync_values (GST_OBJECT (self), ts);
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g_mutex_lock (&self->lock);
*values = _saw_get (self, priv->amplitude, priv->offset, priv->timeshift,
priv->period, priv->frequency, ts);
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g_mutex_unlock (&self->lock);
ts += interval;
values++;
}
return TRUE;
}
static inline gdouble
_rsaw_get (GstLFOControlSource * self, gdouble amp, gdouble off,
GstClockTime timeshift, GstClockTime period, gdouble frequency,
GstClockTime timestamp)
{
gdouble pos =
gst_guint64_to_gdouble (_calculate_pos (timestamp, timeshift, period));
gdouble per = gst_guint64_to_gdouble (period);
gdouble ret;
ret = (pos - per / 2.0) * ((2.0 * amp) / per);
ret += off;
return ret;
}
static gboolean
waveform_rsaw_get (GstLFOControlSource * self, GstClockTime timestamp,
gdouble * value)
{
GstLFOControlSourcePrivate *priv = self->priv;
gst_object_sync_values (GST_OBJECT (self), timestamp);
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g_mutex_lock (&self->lock);
*value = _rsaw_get (self, priv->amplitude, priv->offset, priv->timeshift,
priv->period, priv->frequency, timestamp);
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g_mutex_unlock (&self->lock);
return TRUE;
}
static gboolean
waveform_rsaw_get_value_array (GstLFOControlSource * self,
GstClockTime timestamp, GstClockTime interval, guint n_values,
gdouble * values)
{
GstLFOControlSourcePrivate *priv = self->priv;
guint i;
GstClockTime ts = timestamp;
for (i = 0; i < n_values; i++) {
gst_object_sync_values (GST_OBJECT (self), ts);
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g_mutex_lock (&self->lock);
*values = _rsaw_get (self, priv->amplitude, priv->offset, priv->timeshift,
priv->period, priv->frequency, ts);
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g_mutex_unlock (&self->lock);
ts += interval;
values++;
}
return TRUE;
}
static inline gdouble
_triangle_get (GstLFOControlSource * self, gdouble amp, gdouble off,
GstClockTime timeshift, GstClockTime period, gdouble frequency,
GstClockTime timestamp)
{
gdouble pos =
gst_guint64_to_gdouble (_calculate_pos (timestamp, timeshift, period));
gdouble per = gst_guint64_to_gdouble (period);
gdouble ret;
if (pos <= 0.25 * per)
/* 1st quarter */
ret = pos * ((4.0 * amp) / per);
else if (pos <= 0.75 * per)
/* 2nd & 3rd quarter */
ret = -(pos - per / 2.0) * ((4.0 * amp) / per);
else
/* 4th quarter */
ret = -(per - pos) * ((4.0 * amp) / per);
ret += off;
return ret;
}
static gboolean
waveform_triangle_get (GstLFOControlSource * self, GstClockTime timestamp,
gdouble * value)
{
GstLFOControlSourcePrivate *priv = self->priv;
gst_object_sync_values (GST_OBJECT (self), timestamp);
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g_mutex_lock (&self->lock);
*value = _triangle_get (self, priv->amplitude, priv->offset, priv->timeshift,
priv->period, priv->frequency, timestamp);
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g_mutex_unlock (&self->lock);
return TRUE;
}
static gboolean
waveform_triangle_get_value_array (GstLFOControlSource * self,
GstClockTime timestamp, GstClockTime interval, guint n_values,
gdouble * values)
{
GstLFOControlSourcePrivate *priv = self->priv;
guint i;
GstClockTime ts = timestamp;
for (i = 0; i < n_values; i++) {
gst_object_sync_values (GST_OBJECT (self), ts);
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g_mutex_lock (&self->lock);
*values =
_triangle_get (self, priv->amplitude, priv->offset, priv->timeshift,
priv->period, priv->frequency, ts);
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g_mutex_unlock (&self->lock);
ts += interval;
values++;
}
return TRUE;
}
static struct
{
GstControlSourceGetValue get;
GstControlSourceGetValueArray get_value_array;
} waveforms[] = {
{
(GstControlSourceGetValue) waveform_sine_get,
(GstControlSourceGetValueArray) waveform_sine_get_value_array}, {
(GstControlSourceGetValue) waveform_square_get,
(GstControlSourceGetValueArray) waveform_square_get_value_array}, {
(GstControlSourceGetValue) waveform_saw_get,
(GstControlSourceGetValueArray) waveform_saw_get_value_array}, {
(GstControlSourceGetValue) waveform_rsaw_get,
(GstControlSourceGetValueArray) waveform_rsaw_get_value_array}, {
(GstControlSourceGetValue) waveform_triangle_get,
(GstControlSourceGetValueArray) waveform_triangle_get_value_array}
};
static const guint num_waveforms = G_N_ELEMENTS (waveforms);
enum
{
PROP_WAVEFORM = 1,
PROP_FREQUENCY,
PROP_TIMESHIFT,
PROP_AMPLITUDE,
PROP_OFFSET
};
#define _do_init \
GST_DEBUG_CATEGORY_INIT (GST_CAT_DEFAULT, "lfo control source", 0, "low frequency oscillator control source")
#define gst_lfo_control_source_parent_class parent_class
G_DEFINE_TYPE_WITH_CODE (GstLFOControlSource, gst_lfo_control_source,
GST_TYPE_CONTROL_SOURCE, _do_init);
static void
gst_lfo_control_source_reset (GstLFOControlSource * self)
{
GstControlSource *csource = GST_CONTROL_SOURCE (self);
csource->get_value = NULL;
csource->get_value_array = NULL;
}
/**
* gst_lfo_control_source_new:
*
* This returns a new, unbound #GstLFOControlSource.
*
* Returns: (transfer full): a new, unbound #GstLFOControlSource.
*/
GstControlSource *
Correct all relevant warnings found by the sparse semantic code analyzer. This include marking several symbols static... Original commit message from CVS: * gst/gstconfig.h.in: * libs/gst/base/gstcollectpads.c: (gst_collect_pads_read_buffer): * libs/gst/check/gstcheck.c: (gst_check_log_message_func), (gst_check_log_critical_func), (gst_check_drop_buffers), (gst_check_element_push_buffer_list): * libs/gst/controller/gstcontroller.c: (gst_controller_get), (gst_controller_get_type): * libs/gst/controller/gsthelper.c: (gst_object_control_properties), (gst_object_get_controller), (gst_object_get_control_source): * libs/gst/controller/gstinterpolationcontrolsource.c: (gst_interpolation_control_source_new): * libs/gst/controller/gstlfocontrolsource.c: (gst_lfo_control_source_new): * libs/gst/dataprotocol/dataprotocol.c: (gst_dp_event_from_packet_0_2): * plugins/elements/gstfdsrc.c: * plugins/elements/gstmultiqueue.c: * plugins/elements/gsttee.c: * plugins/elements/gsttypefindelement.c: * plugins/indexers/gstfileindex.c: (_file_index_id_save_xml), (gst_file_index_add_association): * plugins/indexers/gstmemindex.c: * tests/benchmarks/gstpollstress.c: (mess_some_more): * tests/check/elements/queue.c: (setup_queue): * tests/check/gst/gstpipeline.c: * tests/check/libs/collectpads.c: (setup), (teardown), (gst_collect_pads_suite): * tests/examples/adapter/adapter_test.c: * tests/examples/metadata/read-metadata.c: (make_pipeline): * tests/examples/xml/createxml.c: * tests/examples/xml/runxml.c: * tools/gst-inspect.c: * tools/gst-run.c: Correct all relevant warnings found by the sparse semantic code analyzer. This include marking several symbols static, using NULL instead of 0 for pointers, not using variable sized arrays on the stack, moving variable declarations to the beginning of a block and using "foo (void)" instead of "foo ()" for declarations.
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gst_lfo_control_source_new (void)
{
return g_object_new (GST_TYPE_LFO_CONTROL_SOURCE, NULL);
}
static gboolean
gst_lfo_control_source_set_waveform (GstLFOControlSource * self,
GstLFOWaveform waveform)
{
GstControlSource *csource = GST_CONTROL_SOURCE (self);
if (waveform >= num_waveforms || (int) waveform < 0) {
GST_WARNING ("waveform %d invalid or not implemented yet", waveform);
return FALSE;
}
csource->get_value = waveforms[waveform].get;
csource->get_value_array = waveforms[waveform].get_value_array;
self->priv->waveform = waveform;
return TRUE;
}
static void
gst_lfo_control_source_init (GstLFOControlSource * self)
{
self->priv =
G_TYPE_INSTANCE_GET_PRIVATE (self, GST_TYPE_LFO_CONTROL_SOURCE,
GstLFOControlSourcePrivate);
self->priv->waveform = gst_lfo_control_source_set_waveform (self,
GST_LFO_WAVEFORM_SINE);
self->priv->frequency = 1.0;
self->priv->amplitude = 1.0;
self->priv->period = GST_SECOND / self->priv->frequency;
self->priv->timeshift = 0;
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g_mutex_init (&self->lock);
}
static void
gst_lfo_control_source_finalize (GObject * obj)
{
GstLFOControlSource *self = GST_LFO_CONTROL_SOURCE (obj);
gst_lfo_control_source_reset (self);
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g_mutex_clear (&self->lock);
G_OBJECT_CLASS (parent_class)->finalize (obj);
}
static void
gst_lfo_control_source_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstLFOControlSource *self = GST_LFO_CONTROL_SOURCE (object);
switch (prop_id) {
case PROP_WAVEFORM:
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g_mutex_lock (&self->lock);
gst_lfo_control_source_set_waveform (self,
(GstLFOWaveform) g_value_get_enum (value));
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g_mutex_unlock (&self->lock);
break;
case PROP_FREQUENCY:{
gdouble frequency = g_value_get_double (value);
g_return_if_fail (((GstClockTime) (GST_SECOND / frequency)) != 0);
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g_mutex_lock (&self->lock);
self->priv->frequency = frequency;
self->priv->period = GST_SECOND / frequency;
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g_mutex_unlock (&self->lock);
break;
}
case PROP_TIMESHIFT:
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g_mutex_lock (&self->lock);
self->priv->timeshift = g_value_get_uint64 (value);
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g_mutex_unlock (&self->lock);
break;
case PROP_AMPLITUDE:
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g_mutex_lock (&self->lock);
self->priv->amplitude = g_value_get_double (value);
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g_mutex_unlock (&self->lock);
break;
case PROP_OFFSET:
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g_mutex_lock (&self->lock);
self->priv->offset = g_value_get_double (value);
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g_mutex_unlock (&self->lock);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_lfo_control_source_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstLFOControlSource *self = GST_LFO_CONTROL_SOURCE (object);
switch (prop_id) {
case PROP_WAVEFORM:
g_value_set_enum (value, self->priv->waveform);
break;
case PROP_FREQUENCY:
g_value_set_double (value, self->priv->frequency);
break;
case PROP_TIMESHIFT:
g_value_set_uint64 (value, self->priv->timeshift);
break;
case PROP_AMPLITUDE:
g_value_set_double (value, self->priv->amplitude);
break;
case PROP_OFFSET:
g_value_set_double (value, self->priv->offset);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_lfo_control_source_class_init (GstLFOControlSourceClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
g_type_class_add_private (klass, sizeof (GstLFOControlSourcePrivate));
gobject_class->finalize = gst_lfo_control_source_finalize;
gobject_class->set_property = gst_lfo_control_source_set_property;
gobject_class->get_property = gst_lfo_control_source_get_property;
/**
* GstLFOControlSource:waveform:
*
* Specifies the waveform that should be used for this #GstLFOControlSource.
*/
g_object_class_install_property (gobject_class, PROP_WAVEFORM,
g_param_spec_enum ("waveform", "Waveform", "Waveform",
Define G_PARAM_STATIC_STRINGS if it's undefined (GLib < 2.13.0) and use it everywhere for GParamSpecs that use static... Original commit message from CVS: * docs/pwg/advanced-dparams.xml: * docs/pwg/building-props.xml: * docs/pwg/other-source.xml: * gst/glib-compat.h: * gst/gstbin.c: (gst_bin_class_init): * gst/gstclock.c: (gst_clock_class_init): * gst/gstindex.c: (gst_index_class_init): * gst/gstobject.c: (gst_object_class_init): * gst/gstpad.c: (gst_pad_class_init): * gst/gstpipeline.c: (gst_pipeline_class_init): * libs/gst/base/gstbasesink.c: (gst_base_sink_class_init): * libs/gst/base/gstbasesrc.c: (gst_base_src_class_init): * libs/gst/base/gstbasetransform.c: (gst_base_transform_class_init): * libs/gst/base/gstdataqueue.c: (gst_data_queue_class_init): * libs/gst/check/gstcheck.c: (_gst_check_fault_handler_restore), (_gst_check_fault_handler_sighandler), (_gst_check_fault_handler_setup), (gst_check_init): * libs/gst/controller/gstcontroller.c: (_gst_controller_class_init): * libs/gst/controller/gstlfocontrolsource.c: (gst_lfo_control_source_class_init): * libs/gst/net/gstnetclientclock.c: (gst_net_client_clock_class_init): * libs/gst/net/gstnettimeprovider.c: (gst_net_time_provider_class_init): * plugins/elements/gstcapsfilter.c: (gst_capsfilter_class_init): * plugins/elements/gstfakesink.c: (gst_fake_sink_class_init): * plugins/elements/gstfakesrc.c: (gst_fake_src_class_init): * plugins/elements/gstfdsink.c: (gst_fd_sink_class_init): * plugins/elements/gstfdsrc.c: (gst_fd_src_class_init): * plugins/elements/gstfilesink.c: (gst_file_sink_class_init): * plugins/elements/gstfilesrc.c: (gst_file_src_class_init): * plugins/elements/gstidentity.c: (gst_identity_class_init): * plugins/elements/gstmultiqueue.c: (gst_multi_queue_class_init): * plugins/elements/gstqueue.c: (gst_queue_class_init): * plugins/elements/gsttee.c: (gst_tee_class_init): * plugins/elements/gsttypefindelement.c: (gst_type_find_element_class_init): * plugins/indexers/gstfileindex.c: (gst_file_index_class_init): Define G_PARAM_STATIC_STRINGS if it's undefined (GLib < 2.13.0) and use it everywhere for GParamSpecs that use static strings (i.e. all). This gives us less memory usage, fewer allocations and thus less memory defragmentation. Fixes bug #523806.
2008-03-22 14:56:17 +00:00
GST_TYPE_LFO_WAVEFORM, GST_LFO_WAVEFORM_SINE,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
/**
* GstLFOControlSource:frequency:
*
* Specifies the frequency that should be used for the waveform
* of this #GstLFOControlSource. It should be large enough
* so that the period is longer than one nanosecond.
*/
g_object_class_install_property (gobject_class, PROP_FREQUENCY,
g_param_spec_double ("frequency", "Frequency",
"Frequency of the waveform", DBL_MIN, G_MAXDOUBLE, 1.0,
G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
/**
* GstLFOControlSource:timeshift:
*
* Specifies the timeshift to the right that should be used for the waveform
* of this #GstLFOControlSource in nanoseconds.
*
* To get a n nanosecond shift to the left use
* "(GST_SECOND / frequency) - n".
*
*/
g_object_class_install_property (gobject_class, PROP_TIMESHIFT,
g_param_spec_uint64 ("timeshift", "Timeshift",
"Timeshift of the waveform to the right", 0, G_MAXUINT64, 0,
G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
/**
* GstLFOControlSource:amplitude:
*
* Specifies the amplitude for the waveform of this #GstLFOControlSource.
*/
g_object_class_install_property (gobject_class, PROP_AMPLITUDE,
g_param_spec_double ("amplitude", "Amplitude",
"Amplitude of the waveform", 0.0, 1.0, 1.0,
G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
/**
* GstLFOControlSource:offset:
*
* Specifies the value offset for the waveform of this #GstLFOControlSource.
*/
g_object_class_install_property (gobject_class, PROP_OFFSET,
g_param_spec_double ("offset", "Offset", "Offset of the waveform",
0.0, 1.0, 1.0,
G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
}