gstreamer/ges/ges-audio-track.c
2021-01-19 11:08:32 -03:00

206 lines
6 KiB
C

/* GStreamer Editing Services
* Copyright (C) <2013> Thibault Saunier <thibault.saunier@collabora.com>
*
* 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: gesaudiotrack
* @title: GESAudioTrack
* @short_description: A standard #GESTrack for raw audio
*
* A #GESAudioTrack is a default audio #GESTrack, with a
* #GES_TRACK_TYPE_AUDIO #GESTrack:track-type and "audio/x-raw(ANY)"
* #GESTrack:caps.
*
* By default, an audio track will have its #GESTrack:restriction-caps
* set to "audio/x-raw" with the following properties:
*
* - format: "S32LE"
* - channels: 2
* - rate: 44100
* - layout: "interleaved"
*
* These fields are needed for negotiation purposes, but you can change
* their values if you wish. It is advised that you do so using
* ges_track_update_restriction_caps() with new values for the fields you
* wish to change, and any additional fields you may want to add. Unlike
* using ges_track_set_restriction_caps(), this will ensure that these
* default fields will at least have some value set.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "ges-internal.h"
#include "ges-smart-adder.h"
#include "ges-audio-track.h"
#define DEFAULT_CAPS "audio/x-raw"
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
#define DEFAULT_RESTRICTION_CAPS "audio/x-raw, format=S32LE, channels=2, "\
"rate=44100, layout=interleaved"
#else
#define DEFAULT_RESTRICTION_CAPS "audio/x-raw, format=S32BE, channels=2, "\
"rate=44100, layout=interleaved"
#endif
struct _GESAudioTrackPrivate
{
gpointer nothing;
};
G_DEFINE_TYPE_WITH_PRIVATE (GESAudioTrack, ges_audio_track, GES_TYPE_TRACK);
/****************************************************
* Private methods and utils *
****************************************************/
static void
_sync_capsfilter_with_track (GESTrack * track, GstElement * capsfilter)
{
GstCaps *restriction, *caps;
gint rate;
GstStructure *structure;
g_object_get (track, "restriction-caps", &restriction, NULL);
if (restriction == NULL)
return;
if (gst_caps_get_size (restriction) == 0)
goto done;
structure = gst_caps_get_structure (restriction, 0);
if (!gst_structure_get_int (structure, "rate", &rate))
goto done;
caps = gst_caps_new_simple ("audio/x-raw", "rate", G_TYPE_INT, rate, NULL);
g_object_set (capsfilter, "caps", caps, NULL);
gst_caps_unref (caps);
done:
gst_caps_unref (restriction);
}
static void
_track_restriction_changed_cb (GESTrack * track, GParamSpec * arg G_GNUC_UNUSED,
GstElement * capsfilter)
{
_sync_capsfilter_with_track (track, capsfilter);
}
static void
_weak_notify_cb (GESTrack * track, GstElement * capsfilter)
{
g_signal_handlers_disconnect_by_func (track,
(GCallback) _track_restriction_changed_cb, capsfilter);
}
static GstElement *
create_element_for_raw_audio_gap (GESTrack * track)
{
GstElement *bin;
GstElement *capsfilter;
bin = gst_parse_bin_from_description
("audiotestsrc wave=silence name=src ! audioconvert ! audioresample ! audioconvert ! capsfilter name=gapfilter caps=audio/x-raw",
TRUE, NULL);
capsfilter = gst_bin_get_by_name (GST_BIN (bin), "gapfilter");
g_object_weak_ref (G_OBJECT (capsfilter), (GWeakNotify) _weak_notify_cb,
track);
g_signal_connect (track, "notify::restriction-caps",
(GCallback) _track_restriction_changed_cb, capsfilter);
_sync_capsfilter_with_track (track, capsfilter);
gst_object_unref (capsfilter);
return bin;
}
/****************************************************
* GObject vmethods implementations *
****************************************************/
static void
ges_audio_track_init (GESAudioTrack * self)
{
self->priv = ges_audio_track_get_instance_private (self);
}
static void
ges_audio_track_finalize (GObject * object)
{
/* TODO: Add deinitalization code here */
G_OBJECT_CLASS (ges_audio_track_parent_class)->finalize (object);
}
static void
ges_audio_track_class_init (GESAudioTrackClass * klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
/* GESTrackClass *parent_class = GES_TRACK_CLASS (klass);
*/
object_class->finalize = ges_audio_track_finalize;
GES_TRACK_CLASS (klass)->get_mixing_element = ges_smart_adder_new;
}
/****************************************************
* API implementation *
****************************************************/
/**
* ges_audio_track_new:
*
* Creates a new audio track, with a #GES_TRACK_TYPE_AUDIO
* #GESTrack:track-type, "audio/x-raw(ANY)" #GESTrack:caps, and
* "audio/x-raw" #GESTrack:restriction-caps with the properties:
*
* - format: "S32LE"
* - channels: 2
* - rate: 44100
* - layout: "interleaved"
*
* You should use ges_track_update_restriction_caps() if you wish to
* modify these fields, or add additional ones.
*
* Returns: (transfer floating): The newly created audio track.
*/
GESAudioTrack *
ges_audio_track_new (void)
{
GESAudioTrack *ret;
GstCaps *caps = gst_caps_from_string (DEFAULT_CAPS);
GstCaps *restriction_caps = gst_caps_from_string (DEFAULT_RESTRICTION_CAPS);
ret = g_object_new (GES_TYPE_AUDIO_TRACK, "caps", caps,
"track-type", GES_TRACK_TYPE_AUDIO, NULL);
ges_track_set_create_element_for_gap_func (GES_TRACK (ret),
create_element_for_raw_audio_gap);
ges_track_set_restriction_caps (GES_TRACK (ret), restriction_caps);
gst_caps_unref (caps);
gst_caps_unref (restriction_caps);
return ret;
}