gstreamer/gst-libs/gst/audio/gstaudioclock.c
Sebastian Dröge 2a8784e218 audioclock: Sink the reference in the constructor
This is now needed as GstClock does not do that internally anymore,
because that broke bindings.

And mark the function correctly as (transfer full), which it already was
before.

https://bugzilla.gnome.org/show_bug.cgi?id=743062
2017-05-17 10:40:52 +03:00

241 lines
6.7 KiB
C

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wtay@chello.be>
*
* audioclock.c: Clock for use by audio plugins
*
* 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:gstaudioclock
* @title: GstAudioClock
* @short_description: Helper object for implementing audio clocks
* @see_also: #GstAudioBaseSink, #GstSystemClock
*
* #GstAudioClock makes it easy for elements to implement a #GstClock, they
* simply need to provide a function that returns the current clock time.
*
* This object is internally used to implement the clock in #GstAudioBaseSink.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "gstaudioclock.h"
GST_DEBUG_CATEGORY_STATIC (gst_audio_clock_debug);
#define GST_CAT_DEFAULT gst_audio_clock_debug
static void gst_audio_clock_dispose (GObject * object);
static GstClockTime gst_audio_clock_get_internal_time (GstClock * clock);
#define parent_class gst_audio_clock_parent_class
G_DEFINE_TYPE (GstAudioClock, gst_audio_clock, GST_TYPE_SYSTEM_CLOCK);
static void
gst_audio_clock_class_init (GstAudioClockClass * klass)
{
GstClockClass *gstclock_class;
GObjectClass *gobject_class;
gobject_class = (GObjectClass *) klass;
gstclock_class = (GstClockClass *) klass;
gobject_class->dispose = gst_audio_clock_dispose;
gstclock_class->get_internal_time = gst_audio_clock_get_internal_time;
GST_DEBUG_CATEGORY_INIT (gst_audio_clock_debug, "audioclock", 0,
"audioclock");
}
static void
gst_audio_clock_init (GstAudioClock * clock)
{
GST_DEBUG_OBJECT (clock, "init");
clock->last_time = 0;
clock->time_offset = 0;
GST_OBJECT_FLAG_SET (clock, GST_CLOCK_FLAG_CAN_SET_MASTER);
}
static void
gst_audio_clock_dispose (GObject * object)
{
GstAudioClock *clock = GST_AUDIO_CLOCK (object);
if (clock->destroy_notify && clock->user_data)
clock->destroy_notify (clock->user_data);
clock->destroy_notify = NULL;
clock->user_data = NULL;
G_OBJECT_CLASS (parent_class)->dispose (object);
}
/**
* gst_audio_clock_new:
* @name: the name of the clock
* @func: a function
* @user_data: user data
* @destroy_notify: #GDestroyNotify for @user_data
*
* Create a new #GstAudioClock instance. Whenever the clock time should be
* calculated it will call @func with @user_data. When @func returns
* #GST_CLOCK_TIME_NONE, the clock will return the last reported time.
*
* Returns: (transfer full): a new #GstAudioClock casted to a #GstClock.
*/
GstClock *
gst_audio_clock_new (const gchar * name, GstAudioClockGetTimeFunc func,
gpointer user_data, GDestroyNotify destroy_notify)
{
GstAudioClock *aclock =
GST_AUDIO_CLOCK (g_object_new (GST_TYPE_AUDIO_CLOCK, "name", name,
"clock-type", GST_CLOCK_TYPE_OTHER, NULL));
aclock->func = func;
aclock->user_data = user_data;
aclock->destroy_notify = destroy_notify;
gst_object_ref_sink (aclock);
return (GstClock *) aclock;
}
/**
* gst_audio_clock_reset:
* @clock: a #GstAudioClock
* @time: a #GstClockTime
*
* Inform @clock that future calls to #GstAudioClockGetTimeFunc will return values
* starting from @time. The clock will update an internal offset to make sure that
* future calls to internal_time will return an increasing result as required by
* the #GstClock object.
*/
void
gst_audio_clock_reset (GstAudioClock * clock, GstClockTime time)
{
GstClockTimeDiff time_offset;
if (clock->last_time >= time)
time_offset = clock->last_time - time;
else
time_offset = -(time - clock->last_time);
clock->time_offset = time_offset;
GST_DEBUG_OBJECT (clock,
"reset clock to %" GST_TIME_FORMAT ", last %" GST_TIME_FORMAT
", offset %" GST_STIME_FORMAT, GST_TIME_ARGS (time),
GST_TIME_ARGS (clock->last_time), GST_STIME_ARGS (time_offset));
}
static GstClockTime
gst_audio_clock_func_invalid (GstClock * clock, gpointer user_data)
{
return GST_CLOCK_TIME_NONE;
}
static GstClockTime
gst_audio_clock_get_internal_time (GstClock * clock)
{
GstAudioClock *aclock;
GstClockTime result;
aclock = GST_AUDIO_CLOCK_CAST (clock);
result = aclock->func (clock, aclock->user_data);
if (result == GST_CLOCK_TIME_NONE) {
result = aclock->last_time;
} else {
result += aclock->time_offset;
/* clock must be increasing */
if (aclock->last_time < result)
aclock->last_time = result;
else
result = aclock->last_time;
}
GST_DEBUG_OBJECT (clock,
"result %" GST_TIME_FORMAT ", last_time %" GST_TIME_FORMAT,
GST_TIME_ARGS (result), GST_TIME_ARGS (aclock->last_time));
return result;
}
/**
* gst_audio_clock_get_time:
* @clock: a #GstAudioClock
*
* Report the time as returned by the #GstAudioClockGetTimeFunc without applying
* any offsets.
*
* Returns: the time as reported by the time function of the audio clock
*/
GstClockTime
gst_audio_clock_get_time (GstAudioClock * clock)
{
GstClockTime result;
result = clock->func (GST_CLOCK_CAST (clock), clock->user_data);
if (result == GST_CLOCK_TIME_NONE) {
GST_DEBUG_OBJECT (clock, "no time, reuse last");
result = clock->last_time - clock->time_offset;
}
GST_DEBUG_OBJECT (clock,
"result %" GST_TIME_FORMAT ", last_time %" GST_TIME_FORMAT,
GST_TIME_ARGS (result), GST_TIME_ARGS (clock->last_time));
return result;
}
/**
* gst_audio_clock_adjust:
* @clock: a #GstAudioClock
* @time: a #GstClockTime
*
* Adjust @time with the internal offset of the audio clock.
*
* Returns: @time adjusted with the internal offset.
*/
GstClockTime
gst_audio_clock_adjust (GstAudioClock * clock, GstClockTime time)
{
GstClockTime result;
result = time + clock->time_offset;
return result;
}
/**
* gst_audio_clock_invalidate:
* @clock: a #GstAudioClock
*
* Invalidate the clock function. Call this function when the provided
* #GstAudioClockGetTimeFunc cannot be called anymore, for example, when the
* user_data becomes invalid.
*
* After calling this function, @clock will return the last returned time for
* the rest of its lifetime.
*/
void
gst_audio_clock_invalidate (GstAudioClock * clock)
{
clock->func = gst_audio_clock_func_invalid;
}