gstreamer/subprojects/gst-editing-services/ges/ges-effect.c

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/* GStreamer Editing Services
* Copyright (C) 2010 Thibault Saunier <thibault.saunier@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
2012-11-04 00:25:20 +00:00
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:geseffect
* @title: GESEffect
* @short_description: adds an effect build from a parse-launch style bin
* description to a stream in a GESSourceClip or a GESLayer
*
* Any GStreamer filter can be used as effects in GES. The only restriction we
* have is that effects element should have a single [sinkpad](GST_PAD_SINK)
* (which will be requested if necessary) and a single [srcpad](GST_PAD_SRC).
*
* Note that `gesaudiomixer` and `gescompositor` can be used as effects even
* though they can have several sinkpads.
*
* ## GES specific effects:
*
* * **`gesvideoscale`**: GES implements a specific scaling bin that allows
* specifying where scaling will happen inside the chain of effects. By
* default scaling can happen either in the source (if the source doesn't have
* a specific size, like `videotestsrc` or [mixing](ges_track_set_mixing) has
* been disabled) or in the mixing element otherwise, when adding that element
* as an effect, GES guarantees that the scaling will happen in it. This can
* be useful for example if you want to crop the video before scaling or apply
* rounding corners to the video after scaling, etc...
*
* > Note: GES always adds converters (`audioconvert ! audioresample !
* > audioconvert` for audio effects and `videoconvert` for video effects) to
* > make it simpler for end users.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "ges-internal.h"
#include "ges-extractable.h"
#include "ges-track-element.h"
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#include "ges-base-effect.h"
#include "ges-effect-asset.h"
#include "ges-effect.h"
static void ges_extractable_interface_init (GESExtractableInterface * iface);
static void ges_effect_dispose (GObject * object);
static void ges_effect_finalize (GObject * object);
static GstElement *ges_effect_create_element (GESTrackElement * self);
struct _GESEffectPrivate
{
gchar *bin_description;
};
enum
{
PROP_0,
PROP_BIN_DESCRIPTION,
};
G_DEFINE_TYPE_WITH_CODE (GESEffect,
ges_effect, GES_TYPE_BASE_EFFECT, G_ADD_PRIVATE (GESEffect)
G_IMPLEMENT_INTERFACE (GES_TYPE_EXTRACTABLE,
ges_extractable_interface_init));
static gchar *
extractable_check_id (GType type, const gchar * id, GError ** error)
{
gchar *bin_desc, *real_id;
GESTrackType ttype;
bin_desc = ges_effect_asset_id_get_type_and_bindesc (id, &ttype, error);
if (bin_desc == NULL)
return NULL;
if (ttype == GES_TRACK_TYPE_AUDIO)
real_id = g_strdup_printf ("audio %s", bin_desc);
else if (ttype == GES_TRACK_TYPE_VIDEO)
real_id = g_strdup_printf ("video %s", bin_desc);
else
g_assert_not_reached ();
g_free (bin_desc);
return real_id;
}
G_GNUC_BEGIN_IGNORE_DEPRECATIONS; /* Start ignoring GParameter deprecation */
static GParameter *
extractable_get_parameters_from_id (const gchar * id, guint * n_params)
{
GParameter *params = g_new0 (GParameter, 3);
gchar *bin_desc;
GESTrackType ttype;
bin_desc = ges_effect_asset_id_get_type_and_bindesc (id, &ttype, NULL);
params[0].name = "bin-description";
g_value_init (&params[0].value, G_TYPE_STRING);
g_value_set_string (&params[0].value, bin_desc);
params[1].name = "track-type";
g_value_init (&params[1].value, GES_TYPE_TRACK_TYPE);
g_value_set_flags (&params[1].value, ttype);
*n_params = 2;
g_free (bin_desc);
return params;
}
G_GNUC_END_IGNORE_DEPRECATIONS; /* End ignoring GParameter deprecation */
static gchar *
extractable_get_id (GESExtractable * self)
{
return g_strdup (GES_EFFECT (self)->priv->bin_description);
}
static void
ges_extractable_interface_init (GESExtractableInterface * iface)
{
iface->asset_type = GES_TYPE_EFFECT_ASSET;
iface->check_id = (GESExtractableCheckId) extractable_check_id;
iface->get_parameters_from_id = extractable_get_parameters_from_id;
iface->get_id = extractable_get_id;
}
static int
property_name_compare (gconstpointer s1, gconstpointer s2)
{
return g_strcmp0 ((const gchar *) s1, (const gchar *) s2);
}
static void
ges_effect_get_property (GObject * object,
guint property_id, GValue * value, GParamSpec * pspec)
{
GESEffectPrivate *priv = GES_EFFECT (object)->priv;
switch (property_id) {
case PROP_BIN_DESCRIPTION:
g_value_set_string (value, priv->bin_description);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}
}
static void
ges_effect_set_property (GObject * object,
guint property_id, const GValue * value, GParamSpec * pspec)
{
GESEffect *self = GES_EFFECT (object);
switch (property_id) {
case PROP_BIN_DESCRIPTION:
self->priv->bin_description = g_value_dup_string (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}
}
static void
ges_effect_class_init (GESEffectClass * klass)
{
GObjectClass *object_class;
GESTrackElementClass *obj_bg_class;
object_class = G_OBJECT_CLASS (klass);
obj_bg_class = GES_TRACK_ELEMENT_CLASS (klass);
object_class->get_property = ges_effect_get_property;
object_class->set_property = ges_effect_set_property;
object_class->dispose = ges_effect_dispose;
object_class->finalize = ges_effect_finalize;
obj_bg_class->create_element = ges_effect_create_element;
Handle changing playback rate Before this patch, NLE and GES did not support NleOperations (respectively GESEffects) that changed the speed/tempo/rate at which the source plays. For example, the 'pitch' element can make audio play faster or slower. In GES 1.5.90 and before, an NleOperation containing the pitch element to change the rate (or tempo) would cause a pipeline state change to PAUSED after that stack; that has been fixed in 1.5.91 (see #755012 [0]). But even then, in 1.5.91 and later, NleComposition would send segment events to its NleSources assuming that one source second is equal to one pipeline second. The resulting early EOS event (in the case of a source rate higher than 1.0) would cause it to switch stacks too early, causing confusion in the timeline and spectacularly messed up output. This patch fixes that by searching for rate-changing elements in GESTrackElements such as GESEffects. If such rate-changing elements are found, their final effect on the playing rate is stored in the corresponding NleObject as the 'media duration factor', named like this because the 'media duration', or source duration, of an NleObject can be computed by multiplying the duration with the media duration factor of that object and its parents (this is called the 'recursive media duration factor'). For example, a 4-second NleSource with an NleOperation with a media duration factor of 2.0 will have an 8-second media duration, which means that for playing 4 seconds in the pipeline, the seek event sent to it must span 8 seconds of media. (So, the 'duration' of an NleObject or GES object always refers to its duration in the timeline, not the media duration.) To summarize: * Rate-changing elements are registered in the GESEffectClass (pitch::tempo and pitch::rate are registered by default); * GESTimelineElement is responsible for detecting rate-changing elements and computing the media_duration_factor; * GESTrackElement is responsible for storing the media_duration_factor in NleObject; * NleComposition is responsible for the recursive_media_duration_factor; * The latter property finally fixes media time computations in NleObject. NLE and GES tests are included. [0] https://bugzilla.gnome.org/show_bug.cgi?id=755012 Differential Revision: https://phabricator.freedesktop.org/D276
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klass->rate_properties = NULL;
ges_effect_class_register_rate_property (klass, "scaletempo", "rate");
Handle changing playback rate Before this patch, NLE and GES did not support NleOperations (respectively GESEffects) that changed the speed/tempo/rate at which the source plays. For example, the 'pitch' element can make audio play faster or slower. In GES 1.5.90 and before, an NleOperation containing the pitch element to change the rate (or tempo) would cause a pipeline state change to PAUSED after that stack; that has been fixed in 1.5.91 (see #755012 [0]). But even then, in 1.5.91 and later, NleComposition would send segment events to its NleSources assuming that one source second is equal to one pipeline second. The resulting early EOS event (in the case of a source rate higher than 1.0) would cause it to switch stacks too early, causing confusion in the timeline and spectacularly messed up output. This patch fixes that by searching for rate-changing elements in GESTrackElements such as GESEffects. If such rate-changing elements are found, their final effect on the playing rate is stored in the corresponding NleObject as the 'media duration factor', named like this because the 'media duration', or source duration, of an NleObject can be computed by multiplying the duration with the media duration factor of that object and its parents (this is called the 'recursive media duration factor'). For example, a 4-second NleSource with an NleOperation with a media duration factor of 2.0 will have an 8-second media duration, which means that for playing 4 seconds in the pipeline, the seek event sent to it must span 8 seconds of media. (So, the 'duration' of an NleObject or GES object always refers to its duration in the timeline, not the media duration.) To summarize: * Rate-changing elements are registered in the GESEffectClass (pitch::tempo and pitch::rate are registered by default); * GESTimelineElement is responsible for detecting rate-changing elements and computing the media_duration_factor; * GESTrackElement is responsible for storing the media_duration_factor in NleObject; * NleComposition is responsible for the recursive_media_duration_factor; * The latter property finally fixes media time computations in NleObject. NLE and GES tests are included. [0] https://bugzilla.gnome.org/show_bug.cgi?id=755012 Differential Revision: https://phabricator.freedesktop.org/D276
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ges_effect_class_register_rate_property (klass, "pitch", "tempo");
ges_effect_class_register_rate_property (klass, "pitch", "rate");
ges_effect_class_register_rate_property (klass, "videorate", "rate");
Handle changing playback rate Before this patch, NLE and GES did not support NleOperations (respectively GESEffects) that changed the speed/tempo/rate at which the source plays. For example, the 'pitch' element can make audio play faster or slower. In GES 1.5.90 and before, an NleOperation containing the pitch element to change the rate (or tempo) would cause a pipeline state change to PAUSED after that stack; that has been fixed in 1.5.91 (see #755012 [0]). But even then, in 1.5.91 and later, NleComposition would send segment events to its NleSources assuming that one source second is equal to one pipeline second. The resulting early EOS event (in the case of a source rate higher than 1.0) would cause it to switch stacks too early, causing confusion in the timeline and spectacularly messed up output. This patch fixes that by searching for rate-changing elements in GESTrackElements such as GESEffects. If such rate-changing elements are found, their final effect on the playing rate is stored in the corresponding NleObject as the 'media duration factor', named like this because the 'media duration', or source duration, of an NleObject can be computed by multiplying the duration with the media duration factor of that object and its parents (this is called the 'recursive media duration factor'). For example, a 4-second NleSource with an NleOperation with a media duration factor of 2.0 will have an 8-second media duration, which means that for playing 4 seconds in the pipeline, the seek event sent to it must span 8 seconds of media. (So, the 'duration' of an NleObject or GES object always refers to its duration in the timeline, not the media duration.) To summarize: * Rate-changing elements are registered in the GESEffectClass (pitch::tempo and pitch::rate are registered by default); * GESTimelineElement is responsible for detecting rate-changing elements and computing the media_duration_factor; * GESTrackElement is responsible for storing the media_duration_factor in NleObject; * NleComposition is responsible for the recursive_media_duration_factor; * The latter property finally fixes media time computations in NleObject. NLE and GES tests are included. [0] https://bugzilla.gnome.org/show_bug.cgi?id=755012 Differential Revision: https://phabricator.freedesktop.org/D276
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/**
* GESEffect:bin-description:
*
* The description of the effect bin with a gst-launch-style
* pipeline description.
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*
* Example: "videobalance saturation=1.5 hue=+0.5"
*/
g_object_class_install_property (object_class, PROP_BIN_DESCRIPTION,
g_param_spec_string ("bin-description",
"bin description",
"Bin description of the effect",
NULL, G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY));
}
static void
ges_effect_init (GESEffect * self)
{
self->priv = ges_effect_get_instance_private (self);
}
static void
ges_effect_dispose (GObject * object)
{
G_OBJECT_CLASS (ges_effect_parent_class)->dispose (object);
}
static void
ges_effect_finalize (GObject * object)
{
GESEffect *self = GES_EFFECT (object);
if (self->priv->bin_description)
g_free (self->priv->bin_description);
G_OBJECT_CLASS (ges_effect_parent_class)->finalize (object);
}
static gdouble
_get_rate_factor (GESBaseEffect * effect, GHashTable * rate_values)
{
GHashTableIter iter;
gpointer key, val;
gdouble factor = 1.0;
g_hash_table_iter_init (&iter, rate_values);
while (g_hash_table_iter_next (&iter, &key, &val)) {
GValue *value = val;
gchar *prop_name = key;
gdouble rate = 1.0;
switch (G_VALUE_TYPE (value)) {
case G_TYPE_DOUBLE:
rate = g_value_get_double (value);
break;
case G_TYPE_FLOAT:
rate = g_value_get_float (value);
break;
default:
GST_ERROR_OBJECT (effect, "Rate property %s has neither a gdouble "
"nor gfloat value", prop_name);
break;
}
factor *= rate;
}
return factor;
}
static GstClockTime
_rate_source_to_sink (GESBaseEffect * effect, GstClockTime time,
GHashTable * rate_values, gpointer user_data)
{
/* multiply by rate factor
* E.g. rate=2.0, then the time 30 at the source would become
* 60 at the sink because we are using up twice as much data in a given
* time */
gdouble rate_factor = _get_rate_factor (effect, rate_values);
if (time == 0)
return 0;
if (rate_factor == 0.0) {
GST_ERROR_OBJECT (effect, "The rate effect has a rate of 0");
return 0;
}
return (GstClockTime) (time * rate_factor);
}
static GstClockTime
_rate_sink_to_source (GESBaseEffect * effect, GstClockTime time,
GHashTable * rate_values, gpointer user_data)
{
/* divide by rate factor */
gdouble rate_factor = _get_rate_factor (effect, rate_values);
if (time == 0)
return 0;
if (rate_factor == 0.0) {
GST_ERROR_OBJECT (effect, "The rate effect has a rate of 0");
return GST_CLOCK_TIME_NONE;
}
return (GstClockTime) (time / rate_factor);
}
static GstElement *
ges_effect_create_element (GESTrackElement * object)
{
GList *tmp;
GESEffectClass *class;
GstElement *effect;
gboolean is_rate_effect = FALSE;
GESBaseEffect *base_effect = GES_BASE_EFFECT (object);
GError *error = NULL;
GESEffect *self = GES_EFFECT (object);
const gchar *blacklisted_factories[] =
{ "audioconvert", "audioresample", "videoconvert", NULL };
GESTrackType type = ges_track_element_get_track_type (object);
if (!g_strcmp0 (self->priv->bin_description, "gesaudiomixer") ||
!g_strcmp0 (self->priv->bin_description, "gescompositor"))
return gst_element_factory_make (self->priv->bin_description, NULL);
effect =
ges_effect_from_description (self->priv->bin_description, type, &error);
if (error != NULL) {
GST_ERROR ("An error occurred while creating the GstElement: %s",
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error->message);
g_error_free (error);
goto fail;
}
ges_track_element_add_children_props (object, effect, NULL,
blacklisted_factories, NULL);
class = GES_EFFECT_CLASS (g_type_class_peek (GES_TYPE_EFFECT));
for (tmp = class->rate_properties; tmp; tmp = tmp->next) {
gchar *prop = tmp->data;
if (ges_timeline_element_lookup_child (GES_TIMELINE_ELEMENT (object), prop,
NULL, NULL)) {
if (!ges_base_effect_register_time_property (base_effect, prop))
GST_ERROR_OBJECT (object, "Failed to register rate property %s", prop);
is_rate_effect = TRUE;
}
}
if (is_rate_effect
&& !ges_base_effect_set_time_translation_funcs (base_effect,
_rate_source_to_sink, _rate_sink_to_source, NULL, NULL))
GST_ERROR_OBJECT (object, "Failed to set rate translation functions");
done:
return effect;
fail:
gst_clear_object (&effect);
goto done;
}
/**
* ges_effect_new:
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* @bin_description: The gst-launch like bin description of the effect
*
* Creates a new #GESEffect from the description of the bin. It should be
* possible to determine the type of the effect through the element
* 'klass' metadata of the GstElements that will be created.
* In that corner case, you should use:
* #ges_asset_request (GES_TYPE_EFFECT, "audio your ! bin ! description", NULL);
* and extract that asset to be in full control.
2011-05-06 17:38:26 +00:00
*
* Returns: (nullable): a newly created #GESEffect, or %NULL if something went
2011-05-06 17:38:26 +00:00
* wrong.
*/
GESEffect *
ges_effect_new (const gchar * bin_description)
{
GESEffect *effect;
GError *error = NULL;
GESAsset *asset = ges_asset_request (GES_TYPE_EFFECT,
bin_description, &error);
if (error != NULL) {
GST_ERROR ("Error requesting asset with description \"%s\": %s",
bin_description, error->message);
g_error_free (error);
/* fall-through */
}
g_return_val_if_fail (asset, NULL);
effect = GES_EFFECT (ges_asset_extract (asset, NULL));
gst_object_unref (asset);
return effect;
}
Handle changing playback rate Before this patch, NLE and GES did not support NleOperations (respectively GESEffects) that changed the speed/tempo/rate at which the source plays. For example, the 'pitch' element can make audio play faster or slower. In GES 1.5.90 and before, an NleOperation containing the pitch element to change the rate (or tempo) would cause a pipeline state change to PAUSED after that stack; that has been fixed in 1.5.91 (see #755012 [0]). But even then, in 1.5.91 and later, NleComposition would send segment events to its NleSources assuming that one source second is equal to one pipeline second. The resulting early EOS event (in the case of a source rate higher than 1.0) would cause it to switch stacks too early, causing confusion in the timeline and spectacularly messed up output. This patch fixes that by searching for rate-changing elements in GESTrackElements such as GESEffects. If such rate-changing elements are found, their final effect on the playing rate is stored in the corresponding NleObject as the 'media duration factor', named like this because the 'media duration', or source duration, of an NleObject can be computed by multiplying the duration with the media duration factor of that object and its parents (this is called the 'recursive media duration factor'). For example, a 4-second NleSource with an NleOperation with a media duration factor of 2.0 will have an 8-second media duration, which means that for playing 4 seconds in the pipeline, the seek event sent to it must span 8 seconds of media. (So, the 'duration' of an NleObject or GES object always refers to its duration in the timeline, not the media duration.) To summarize: * Rate-changing elements are registered in the GESEffectClass (pitch::tempo and pitch::rate are registered by default); * GESTimelineElement is responsible for detecting rate-changing elements and computing the media_duration_factor; * GESTrackElement is responsible for storing the media_duration_factor in NleObject; * NleComposition is responsible for the recursive_media_duration_factor; * The latter property finally fixes media time computations in NleObject. NLE and GES tests are included. [0] https://bugzilla.gnome.org/show_bug.cgi?id=755012 Differential Revision: https://phabricator.freedesktop.org/D276
2015-12-20 13:03:57 +00:00
/**
* ges_effect_class_register_rate_property:
* @klass: Instance of the GESEffectClass
* @element_name: The #GstElementFactory name of the element that changes
* the rate
* @property_name: The name of the property that changes the rate
*
* Register an element that can change the rate at which media is playing.
* The property type must be float or double, and must be a factor of the
* rate, i.e. a value of 2.0 must mean that the media plays twice as fast.
* Several properties may be registered for a single element type,
* provided they all contribute to the rate as independent factors. For
* example, this is true for the "GstPitch::rate" and "GstPitch::tempo"
* properties. These are already registered by default in GES, along with
* #videorate:rate for #videorate and #scaletempo:rate for #scaletempo.
*
* If such a rate property becomes a child property of a #GESEffect upon
* its creation (the element is part of its #GESEffect:bin-description),
* it will be automatically registered as a time property (see
* ges_base_effect_register_time_property()) and will have its time
* translation functions set (see
* ges_base_effect_set_time_translation_funcs()) to use the overall rate
* of the rate properties. Note that if an effect contains a rate
* property as well as a non-rate time property, you should ensure to set
* the time translation functions to some other methods using
* ges_base_effect_set_time_translation_funcs().
Handle changing playback rate Before this patch, NLE and GES did not support NleOperations (respectively GESEffects) that changed the speed/tempo/rate at which the source plays. For example, the 'pitch' element can make audio play faster or slower. In GES 1.5.90 and before, an NleOperation containing the pitch element to change the rate (or tempo) would cause a pipeline state change to PAUSED after that stack; that has been fixed in 1.5.91 (see #755012 [0]). But even then, in 1.5.91 and later, NleComposition would send segment events to its NleSources assuming that one source second is equal to one pipeline second. The resulting early EOS event (in the case of a source rate higher than 1.0) would cause it to switch stacks too early, causing confusion in the timeline and spectacularly messed up output. This patch fixes that by searching for rate-changing elements in GESTrackElements such as GESEffects. If such rate-changing elements are found, their final effect on the playing rate is stored in the corresponding NleObject as the 'media duration factor', named like this because the 'media duration', or source duration, of an NleObject can be computed by multiplying the duration with the media duration factor of that object and its parents (this is called the 'recursive media duration factor'). For example, a 4-second NleSource with an NleOperation with a media duration factor of 2.0 will have an 8-second media duration, which means that for playing 4 seconds in the pipeline, the seek event sent to it must span 8 seconds of media. (So, the 'duration' of an NleObject or GES object always refers to its duration in the timeline, not the media duration.) To summarize: * Rate-changing elements are registered in the GESEffectClass (pitch::tempo and pitch::rate are registered by default); * GESTimelineElement is responsible for detecting rate-changing elements and computing the media_duration_factor; * GESTrackElement is responsible for storing the media_duration_factor in NleObject; * NleComposition is responsible for the recursive_media_duration_factor; * The latter property finally fixes media time computations in NleObject. NLE and GES tests are included. [0] https://bugzilla.gnome.org/show_bug.cgi?id=755012 Differential Revision: https://phabricator.freedesktop.org/D276
2015-12-20 13:03:57 +00:00
*
* Note, you can obtain a reference to the GESEffectClass using
Handle changing playback rate Before this patch, NLE and GES did not support NleOperations (respectively GESEffects) that changed the speed/tempo/rate at which the source plays. For example, the 'pitch' element can make audio play faster or slower. In GES 1.5.90 and before, an NleOperation containing the pitch element to change the rate (or tempo) would cause a pipeline state change to PAUSED after that stack; that has been fixed in 1.5.91 (see #755012 [0]). But even then, in 1.5.91 and later, NleComposition would send segment events to its NleSources assuming that one source second is equal to one pipeline second. The resulting early EOS event (in the case of a source rate higher than 1.0) would cause it to switch stacks too early, causing confusion in the timeline and spectacularly messed up output. This patch fixes that by searching for rate-changing elements in GESTrackElements such as GESEffects. If such rate-changing elements are found, their final effect on the playing rate is stored in the corresponding NleObject as the 'media duration factor', named like this because the 'media duration', or source duration, of an NleObject can be computed by multiplying the duration with the media duration factor of that object and its parents (this is called the 'recursive media duration factor'). For example, a 4-second NleSource with an NleOperation with a media duration factor of 2.0 will have an 8-second media duration, which means that for playing 4 seconds in the pipeline, the seek event sent to it must span 8 seconds of media. (So, the 'duration' of an NleObject or GES object always refers to its duration in the timeline, not the media duration.) To summarize: * Rate-changing elements are registered in the GESEffectClass (pitch::tempo and pitch::rate are registered by default); * GESTimelineElement is responsible for detecting rate-changing elements and computing the media_duration_factor; * GESTrackElement is responsible for storing the media_duration_factor in NleObject; * NleComposition is responsible for the recursive_media_duration_factor; * The latter property finally fixes media time computations in NleObject. NLE and GES tests are included. [0] https://bugzilla.gnome.org/show_bug.cgi?id=755012 Differential Revision: https://phabricator.freedesktop.org/D276
2015-12-20 13:03:57 +00:00
*
* ```
Handle changing playback rate Before this patch, NLE and GES did not support NleOperations (respectively GESEffects) that changed the speed/tempo/rate at which the source plays. For example, the 'pitch' element can make audio play faster or slower. In GES 1.5.90 and before, an NleOperation containing the pitch element to change the rate (or tempo) would cause a pipeline state change to PAUSED after that stack; that has been fixed in 1.5.91 (see #755012 [0]). But even then, in 1.5.91 and later, NleComposition would send segment events to its NleSources assuming that one source second is equal to one pipeline second. The resulting early EOS event (in the case of a source rate higher than 1.0) would cause it to switch stacks too early, causing confusion in the timeline and spectacularly messed up output. This patch fixes that by searching for rate-changing elements in GESTrackElements such as GESEffects. If such rate-changing elements are found, their final effect on the playing rate is stored in the corresponding NleObject as the 'media duration factor', named like this because the 'media duration', or source duration, of an NleObject can be computed by multiplying the duration with the media duration factor of that object and its parents (this is called the 'recursive media duration factor'). For example, a 4-second NleSource with an NleOperation with a media duration factor of 2.0 will have an 8-second media duration, which means that for playing 4 seconds in the pipeline, the seek event sent to it must span 8 seconds of media. (So, the 'duration' of an NleObject or GES object always refers to its duration in the timeline, not the media duration.) To summarize: * Rate-changing elements are registered in the GESEffectClass (pitch::tempo and pitch::rate are registered by default); * GESTimelineElement is responsible for detecting rate-changing elements and computing the media_duration_factor; * GESTrackElement is responsible for storing the media_duration_factor in NleObject; * NleComposition is responsible for the recursive_media_duration_factor; * The latter property finally fixes media time computations in NleObject. NLE and GES tests are included. [0] https://bugzilla.gnome.org/show_bug.cgi?id=755012 Differential Revision: https://phabricator.freedesktop.org/D276
2015-12-20 13:03:57 +00:00
* GES_EFFECT_CLASS (g_type_class_ref (GES_TYPE_EFFECT));
* ```
Handle changing playback rate Before this patch, NLE and GES did not support NleOperations (respectively GESEffects) that changed the speed/tempo/rate at which the source plays. For example, the 'pitch' element can make audio play faster or slower. In GES 1.5.90 and before, an NleOperation containing the pitch element to change the rate (or tempo) would cause a pipeline state change to PAUSED after that stack; that has been fixed in 1.5.91 (see #755012 [0]). But even then, in 1.5.91 and later, NleComposition would send segment events to its NleSources assuming that one source second is equal to one pipeline second. The resulting early EOS event (in the case of a source rate higher than 1.0) would cause it to switch stacks too early, causing confusion in the timeline and spectacularly messed up output. This patch fixes that by searching for rate-changing elements in GESTrackElements such as GESEffects. If such rate-changing elements are found, their final effect on the playing rate is stored in the corresponding NleObject as the 'media duration factor', named like this because the 'media duration', or source duration, of an NleObject can be computed by multiplying the duration with the media duration factor of that object and its parents (this is called the 'recursive media duration factor'). For example, a 4-second NleSource with an NleOperation with a media duration factor of 2.0 will have an 8-second media duration, which means that for playing 4 seconds in the pipeline, the seek event sent to it must span 8 seconds of media. (So, the 'duration' of an NleObject or GES object always refers to its duration in the timeline, not the media duration.) To summarize: * Rate-changing elements are registered in the GESEffectClass (pitch::tempo and pitch::rate are registered by default); * GESTimelineElement is responsible for detecting rate-changing elements and computing the media_duration_factor; * GESTrackElement is responsible for storing the media_duration_factor in NleObject; * NleComposition is responsible for the recursive_media_duration_factor; * The latter property finally fixes media time computations in NleObject. NLE and GES tests are included. [0] https://bugzilla.gnome.org/show_bug.cgi?id=755012 Differential Revision: https://phabricator.freedesktop.org/D276
2015-12-20 13:03:57 +00:00
*
* Returns: %TRUE if the rate property was successfully registered. When
* this method returns %FALSE, a warning is emitted with more information.
Handle changing playback rate Before this patch, NLE and GES did not support NleOperations (respectively GESEffects) that changed the speed/tempo/rate at which the source plays. For example, the 'pitch' element can make audio play faster or slower. In GES 1.5.90 and before, an NleOperation containing the pitch element to change the rate (or tempo) would cause a pipeline state change to PAUSED after that stack; that has been fixed in 1.5.91 (see #755012 [0]). But even then, in 1.5.91 and later, NleComposition would send segment events to its NleSources assuming that one source second is equal to one pipeline second. The resulting early EOS event (in the case of a source rate higher than 1.0) would cause it to switch stacks too early, causing confusion in the timeline and spectacularly messed up output. This patch fixes that by searching for rate-changing elements in GESTrackElements such as GESEffects. If such rate-changing elements are found, their final effect on the playing rate is stored in the corresponding NleObject as the 'media duration factor', named like this because the 'media duration', or source duration, of an NleObject can be computed by multiplying the duration with the media duration factor of that object and its parents (this is called the 'recursive media duration factor'). For example, a 4-second NleSource with an NleOperation with a media duration factor of 2.0 will have an 8-second media duration, which means that for playing 4 seconds in the pipeline, the seek event sent to it must span 8 seconds of media. (So, the 'duration' of an NleObject or GES object always refers to its duration in the timeline, not the media duration.) To summarize: * Rate-changing elements are registered in the GESEffectClass (pitch::tempo and pitch::rate are registered by default); * GESTimelineElement is responsible for detecting rate-changing elements and computing the media_duration_factor; * GESTrackElement is responsible for storing the media_duration_factor in NleObject; * NleComposition is responsible for the recursive_media_duration_factor; * The latter property finally fixes media time computations in NleObject. NLE and GES tests are included. [0] https://bugzilla.gnome.org/show_bug.cgi?id=755012 Differential Revision: https://phabricator.freedesktop.org/D276
2015-12-20 13:03:57 +00:00
*/
gboolean
ges_effect_class_register_rate_property (GESEffectClass * klass,
const gchar * element_name, const gchar * property_name)
{
GstElementFactory *element_factory = NULL;
GstElement *element = NULL;
GParamSpec *pspec = NULL;
gchar *full_property_name = NULL;
GType param_type;
gboolean res = FALSE;
element_factory = gst_element_factory_find (element_name);
if (element_factory == NULL) {
GST_WARNING
("Did not add rate property '%s' for element '%s': the element factory could not be found",
property_name, element_name);
goto fail;
}
element = gst_element_factory_create (element_factory, NULL);
if (element == NULL) {
GST_WARNING
("Did not add rate property '%s' for element '%s': the element could not be constructed",
property_name, element_name);
goto fail;
}
pspec =
g_object_class_find_property (G_OBJECT_GET_CLASS (element),
property_name);
if (pspec == NULL) {
GST_WARNING
("Did not add rate property '%s' for element '%s': the element did not have the property name specified",
property_name, element_name);
goto fail;
}
param_type = G_PARAM_SPEC_VALUE_TYPE (pspec);
if (param_type != G_TYPE_FLOAT && param_type != G_TYPE_DOUBLE) {
GST_WARNING
("Did not add rate property '%s' for element '%s': the property is not of float or double type",
property_name, element_name);
goto fail;
}
full_property_name = g_strdup_printf ("%s::%s",
g_type_name (gst_element_factory_get_element_type (element_factory)),
property_name);
if (g_list_find_custom (klass->rate_properties, full_property_name,
property_name_compare) == NULL) {
klass->rate_properties =
g_list_append (klass->rate_properties, full_property_name);
GST_DEBUG ("Added rate property %s", full_property_name);
} else {
g_free (full_property_name);
}
res = TRUE;
fail:
if (element_factory != NULL)
gst_object_unref (element_factory);
if (element != NULL)
gst_object_unref (element);
if (pspec != NULL)
g_param_spec_unref (pspec);
return res;
}