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/* GStreamer
* Copyright (C) 2011 David Schleef <ds@entropywave.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 Street, Suite 500,
* Boston, MA 02110-1335, USA.
*/
/**
* SECTION:element-gstdecklinksink
*
* The decklinksink element is a sink element for BlackMagic DeckLink
* cards.
*
* <refsect2>
* <title>Example launch line</title>
* |[
* gst-launch-1.0 -v videotestsrc ! decklinksink
* ]|
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/gst.h>
#include <gst/video/video.h>
#include "gstdecklink.h"
#include "gstdecklinksink.h"
#include <string.h>
/* FIXME:
* - handle ALLOCATION query
* - provide buffer pool with suitable strides/alignment for video
* - handle video meta
*/
GST_DEBUG_CATEGORY_STATIC (gst_decklink_sink_debug_category);
#define GST_CAT_DEFAULT gst_decklink_sink_debug_category
static void gst_decklink_sink_set_property (GObject * object,
guint property_id, const GValue * value, GParamSpec * pspec);
static void gst_decklink_sink_get_property (GObject * object,
guint property_id, GValue * value, GParamSpec * pspec);
static void gst_decklink_sink_finalize (GObject * object);
static GstStateChangeReturn
gst_decklink_sink_change_state (GstElement * element,
GstStateChange transition);
static GstFlowReturn gst_decklink_sink_videosink_chain (GstPad * pad,
GstObject * parent, GstBuffer * buffer);
static gboolean gst_decklink_sink_videosink_event (GstPad * pad,
GstObject * parent, GstEvent * event);
static gboolean gst_decklink_sink_videosink_query (GstPad * pad,
GstObject * parent, GstQuery * query);
static GstFlowReturn gst_decklink_sink_audiosink_chain (GstPad * pad,
GstObject * parent, GstBuffer * buffer);
static gboolean gst_decklink_sink_audiosink_event (GstPad * pad,
GstObject * parent, GstEvent * event);
static gboolean gst_decklink_sink_audiosink_query (GstPad * pad,
GstObject * parent, GstQuery * query);
#ifdef _MSC_VER
/* COM initialization/uninitialization thread */
static void gst_decklink_sink_com_thread (GstDecklinkSink * sink);
#endif /* _MSC_VER */
enum
{
PROP_0,
PROP_MODE,
PROP_DEVICE_NUMBER
};
/* pad templates */
/* the video sink pad template is created on the fly */
static GstStaticPadTemplate gst_decklink_sink_audiosink_template =
GST_STATIC_PAD_TEMPLATE ("audiosink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("audio/x-raw, format=S16LE, channels=2, rate=48000, "
"layout=interleaved")
);
#define parent_class gst_decklink_sink_parent_class
G_DEFINE_TYPE (GstDecklinkSink, gst_decklink_sink, GST_TYPE_ELEMENT);
static void
gst_decklink_sink_class_init (GstDecklinkSinkClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
gobject_class->set_property = gst_decklink_sink_set_property;
gobject_class->get_property = gst_decklink_sink_get_property;
gobject_class->finalize = gst_decklink_sink_finalize;
element_class->change_state =
GST_DEBUG_FUNCPTR (gst_decklink_sink_change_state);
g_object_class_install_property (gobject_class, PROP_MODE,
g_param_spec_enum ("mode", "Playback Mode",
"Video Mode to use for playback",
GST_TYPE_DECKLINK_MODE, GST_DECKLINK_MODE_NTSC,
(GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
G_PARAM_CONSTRUCT)));
g_object_class_install_property (gobject_class, PROP_DEVICE_NUMBER,
g_param_spec_int ("device-number", "Device number",
"Output device instance to use", 0, G_MAXINT, 0,
(GParamFlags) (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
G_PARAM_CONSTRUCT)));
gst_element_class_add_pad_template (element_class,
gst_pad_template_new ("videosink", GST_PAD_SINK, GST_PAD_ALWAYS,
gst_decklink_mode_get_template_caps ()));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&gst_decklink_sink_audiosink_template));
gst_element_class_set_static_metadata (element_class, "Decklink Sink",
"Video/Sink", "Decklink Sink", "David Schleef <ds@entropywave.com>");
GST_DEBUG_CATEGORY_INIT (gst_decklink_sink_debug_category, "decklinksink", 0,
"debug category for decklinksink element");
}
static void
gst_decklink_sink_init (GstDecklinkSink * decklinksink)
{
GstDecklinkSinkClass *decklinksink_class;
decklinksink_class = GST_DECKLINK_SINK_GET_CLASS (decklinksink);
decklinksink->videosinkpad =
gst_pad_new_from_template (gst_element_class_get_pad_template
(GST_ELEMENT_CLASS (decklinksink_class), "videosink"), "videosink");
gst_pad_set_chain_function (decklinksink->videosinkpad,
GST_DEBUG_FUNCPTR (gst_decklink_sink_videosink_chain));
gst_pad_set_event_function (decklinksink->videosinkpad,
GST_DEBUG_FUNCPTR (gst_decklink_sink_videosink_event));
gst_pad_set_query_function (decklinksink->videosinkpad,
GST_DEBUG_FUNCPTR (gst_decklink_sink_videosink_query));
gst_element_add_pad (GST_ELEMENT (decklinksink), decklinksink->videosinkpad);
decklinksink->audiosinkpad =
gst_pad_new_from_static_template (&gst_decklink_sink_audiosink_template,
"audiosink");
gst_pad_set_chain_function (decklinksink->audiosinkpad,
GST_DEBUG_FUNCPTR (gst_decklink_sink_audiosink_chain));
gst_pad_set_event_function (decklinksink->audiosinkpad,
GST_DEBUG_FUNCPTR (gst_decklink_sink_audiosink_event));
gst_pad_set_query_function (decklinksink->audiosinkpad,
GST_DEBUG_FUNCPTR (gst_decklink_sink_audiosink_query));
gst_element_add_pad (GST_ELEMENT (decklinksink), decklinksink->audiosinkpad);
GST_OBJECT_FLAG_SET (decklinksink, GST_ELEMENT_FLAG_SINK);
g_cond_init (&decklinksink->cond);
g_mutex_init (&decklinksink->mutex);
g_mutex_init (&decklinksink->audio_mutex);
g_cond_init (&decklinksink->audio_cond);
decklinksink->mode = GST_DECKLINK_MODE_NTSC;
decklinksink->device_number = 0;
decklinksink->callback = new Output;
decklinksink->callback->decklinksink = decklinksink;
#ifdef _MSC_VER
g_mutex_init (&decklinksink->com_init_lock);
g_mutex_init (&decklinksink->com_deinit_lock);
g_cond_init (&decklinksink->com_initialized);
g_cond_init (&decklinksink->com_uninitialize);
g_cond_init (&decklinksink->com_uninitialized);
g_mutex_lock (&decklinksink->com_init_lock);
/* create the COM initialization thread */
g_thread_create ((GThreadFunc) gst_decklink_sink_com_thread,
decklinksink, FALSE, NULL);
/* wait until the COM thread signals that COM has been initialized */
g_cond_wait (&decklinksink->com_initialized, &decklinksink->com_init_lock);
g_mutex_unlock (&decklinksink->com_init_lock);
#endif /* _MSC_VER */
}
void
gst_decklink_sink_set_property (GObject * object, guint property_id,
const GValue * value, GParamSpec * pspec)
{
GstDecklinkSink *decklinksink;
g_return_if_fail (GST_IS_DECKLINK_SINK (object));
decklinksink = GST_DECKLINK_SINK (object);
switch (property_id) {
case PROP_MODE:
decklinksink->mode = (GstDecklinkModeEnum) g_value_get_enum (value);
break;
case PROP_DEVICE_NUMBER:
decklinksink->device_number = g_value_get_int (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
break;
}
}
void
gst_decklink_sink_get_property (GObject * object, guint property_id,
GValue * value, GParamSpec * pspec)
{
GstDecklinkSink *decklinksink;
g_return_if_fail (GST_IS_DECKLINK_SINK (object));
decklinksink = GST_DECKLINK_SINK (object);
switch (property_id) {
case PROP_MODE:
g_value_set_enum (value, decklinksink->mode);
break;
case PROP_DEVICE_NUMBER:
g_value_set_int (value, decklinksink->device_number);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
break;
}
}
#ifdef _MSC_VER
static void
gst_decklink_sink_com_thread (GstDecklinkSink * sink)
{
HRESULT res;
g_mutex_lock (sink->com_init_lock);
/* Initialize COM with a MTA for this process. This thread will
* be the first one to enter the apartement and the last one to leave
* it, unitializing COM properly */
res = CoInitializeEx (0, COINIT_MULTITHREADED);
if (res == S_FALSE)
GST_WARNING_OBJECT (sink,
"COM has been already initialized in the same process");
else if (res == RPC_E_CHANGED_MODE)
GST_WARNING_OBJECT (sink, "The concurrency model of COM has changed.");
else
GST_INFO_OBJECT (sink, "COM intialized succesfully");
sink->comInitialized = TRUE;
/* Signal other threads waiting on this condition that COM was initialized */
g_cond_signal (sink->com_initialized);
g_mutex_unlock (sink->com_init_lock);
/* Wait until the unitialize condition is met to leave the COM apartement */
g_mutex_lock (sink->com_deinit_lock);
g_cond_wait (sink->com_uninitialize, sink->com_deinit_lock);
CoUninitialize ();
GST_INFO_OBJECT (sink, "COM unintialized succesfully");
sink->comInitialized = FALSE;
g_cond_signal (sink->com_uninitialized);
g_mutex_unlock (sink->com_deinit_lock);
}
#endif /* _MSC_VER */
void
gst_decklink_sink_finalize (GObject * object)
{
GstDecklinkSink *decklinksink;
decklinksink = GST_DECKLINK_SINK (object);
g_cond_clear (&decklinksink->cond);
g_mutex_clear (&decklinksink->mutex);
g_cond_clear (&decklinksink->audio_cond);
g_mutex_clear (&decklinksink->audio_mutex);
delete decklinksink->callback;
#ifdef _MSC_VER
/* signal the COM thread that it should uninitialize COM */
if (decklinksink->comInitialized) {
g_mutex_lock (&decklinksink->com_deinit_lock);
g_cond_signal (&decklinksink->com_uninitialize);
g_cond_wait (&decklinksink->com_uninitialized,
&decklinksink->com_deinit_lock);
g_mutex_unlock (&decklinksink->com_deinit_lock);
}
g_mutex_clear (&decklinksink->com_init_lock);
g_mutex_clear (&decklinksink->com_deinit_lock);
g_cond_clear (&decklinksink->com_initialized);
g_cond_clear (&decklinksink->com_uninitialize);
g_cond_clear (&decklinksink->com_uninitialized);
#endif /* _MSC_VER */
G_OBJECT_CLASS (parent_class)->finalize (object);
}
/* FIXME: post error messages for the misc. failures */
static gboolean
gst_decklink_sink_start (GstDecklinkSink * decklinksink)
{
HRESULT ret;
const GstDecklinkMode *mode;
BMDAudioSampleType sample_depth;
decklinksink->decklink =
gst_decklink_get_nth_device (decklinksink->device_number);
if (!decklinksink->decklink) {
GST_WARNING ("failed to get device %d", decklinksink->device_number);
return FALSE;
}
decklinksink->output =
gst_decklink_get_nth_output (decklinksink->device_number);
if (!decklinksink->decklink) {
GST_WARNING ("no output for device %d", decklinksink->device_number);
return FALSE;
}
decklinksink->output->SetAudioCallback (decklinksink->callback);
mode = gst_decklink_get_mode (decklinksink->mode);
ret = decklinksink->output->EnableVideoOutput (mode->mode,
bmdVideoOutputFlagDefault);
if (ret != S_OK) {
GST_WARNING ("failed to enable video output");
return FALSE;
}
//decklinksink->video_enabled = TRUE;
decklinksink->output->SetScheduledFrameCompletionCallback (decklinksink->
callback);
sample_depth = bmdAudioSampleType16bitInteger;
ret = decklinksink->output->EnableAudioOutput (bmdAudioSampleRate48kHz,
sample_depth, 2, bmdAudioOutputStreamContinuous);
if (ret != S_OK) {
GST_WARNING ("failed to enable audio output");
return FALSE;
}
decklinksink->audio_adapter = gst_adapter_new ();
decklinksink->num_frames = 0;
return TRUE;
}
static gboolean
gst_decklink_sink_force_stop (GstDecklinkSink * decklinksink)
{
g_mutex_lock (&decklinksink->mutex);
decklinksink->stop = TRUE;
g_cond_signal (&decklinksink->cond);
g_mutex_unlock (&decklinksink->mutex);
g_mutex_lock (&decklinksink->audio_mutex);
g_cond_signal (&decklinksink->audio_cond);
g_mutex_unlock (&decklinksink->audio_mutex);
return TRUE;
}
static gboolean
gst_decklink_sink_stop (GstDecklinkSink * decklinksink)
{
decklinksink->output->StopScheduledPlayback (0, NULL, 0);
decklinksink->output->DisableAudioOutput ();
decklinksink->output->DisableVideoOutput ();
return TRUE;
}
static GstStateChangeReturn
gst_decklink_sink_change_state (GstElement * element, GstStateChange transition)
{
GstDecklinkSink *decklinksink;
GstStateChangeReturn ret;
decklinksink = GST_DECKLINK_SINK (element);
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
if (!gst_decklink_sink_start (decklinksink)) {
ret = GST_STATE_CHANGE_FAILURE;
goto out;
}
break;
case GST_STATE_CHANGE_READY_TO_PAUSED:
break;
case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
break;
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
gst_decklink_sink_force_stop (decklinksink);
break;
case GST_STATE_CHANGE_PAUSED_TO_READY:
break;
case GST_STATE_CHANGE_READY_TO_NULL:
gst_decklink_sink_stop (decklinksink);
break;
default:
break;
}
out:
return ret;
}
static GstFlowReturn
gst_decklink_sink_videosink_chain (GstPad * pad, GstObject * parent,
GstBuffer * buffer)
{
GstDecklinkSink *decklinksink;
IDeckLinkMutableVideoFrame *frame;
void *data;
GstFlowReturn flow_ret;
const GstDecklinkMode *mode;
HRESULT ret;
decklinksink = GST_DECKLINK_SINK (parent);
#if 0
if (!decklinksink->video_enabled) {
HRESULT ret;
ret = decklinksink->output->EnableVideoOutput (decklinksink->display_mode,
bmdVideoOutputFlagDefault);
if (ret != S_OK) {
GST_WARNING ("failed to enable video output");
//return FALSE;
}
decklinksink->video_enabled = TRUE;
}
#endif
mode = gst_decklink_get_mode (decklinksink->mode);
ret = decklinksink->output->CreateVideoFrame (mode->width,
mode->height, mode->width * 2, decklinksink->pixel_format,
bmdFrameFlagDefault, &frame);
if (ret != S_OK) {
GST_ELEMENT_ERROR (decklinksink, STREAM, FAILED,
(NULL), ("Failed to create video frame: 0x%08x", ret));
return GST_FLOW_ERROR;
}
frame->GetBytes (&data);
gst_buffer_extract (buffer, 0, data, gst_buffer_get_size (buffer));
gst_buffer_unref (buffer);
g_mutex_lock (&decklinksink->mutex);
while (decklinksink->queued_frames > 2 && !decklinksink->stop) {
g_cond_wait (&decklinksink->cond, &decklinksink->mutex);
}
if (!decklinksink->stop) {
decklinksink->queued_frames++;
}
g_mutex_unlock (&decklinksink->mutex);
if (!decklinksink->stop) {
ret = decklinksink->output->ScheduleVideoFrame (frame,
decklinksink->num_frames * mode->fps_d, mode->fps_d, mode->fps_n);
if (ret != S_OK) {
GST_ELEMENT_ERROR (decklinksink, STREAM, FAILED,
(NULL), ("Failed to schedule frame: 0x%08x", ret));
flow_ret = GST_FLOW_ERROR;
goto out;
}
decklinksink->num_frames++;
if (!decklinksink->sched_started) {
ret = decklinksink->output->StartScheduledPlayback (0, mode->fps_d, 1.0);
if (ret != S_OK) {
GST_ELEMENT_ERROR (decklinksink, STREAM, FAILED,
(NULL), ("Failed to start scheduled playback: 0x%08x", ret));
flow_ret = GST_FLOW_ERROR;
goto out;
}
decklinksink->sched_started = TRUE;
}
flow_ret = GST_FLOW_OK;
} else {
flow_ret = GST_FLOW_FLUSHING;
}
out:
frame->Release ();
return flow_ret;
}
static gboolean
gst_decklink_sink_videosink_event (GstPad * pad, GstObject * parent,
GstEvent * event)
{
gboolean res;
GstDecklinkSink *decklinksink;
decklinksink = GST_DECKLINK_SINK (parent);
GST_DEBUG_OBJECT (pad, "event: %" GST_PTR_FORMAT, event);
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_CAPS:{
decklinksink->pixel_format = bmdFormat8BitYUV;
res = TRUE;
/* FIXME: this makes no sense, template caps don't contain v210 */
#if 0
GstCaps *caps;
gst_event_parse_caps (event, &caps);
ret = gst_video_format_parse_caps (caps, &format, &width, &height);
if (ret) {
if (format == GST_VIDEO_FORMAT_v210) {
decklinksink->pixel_format = bmdFormat10BitYUV;
} else {
decklinksink->pixel_format = bmdFormat8BitYUV;
}
}
#endif
break;
}
case GST_EVENT_EOS:
/* FIXME: EOS aggregation with audio pad looks wrong */
decklinksink->video_eos = TRUE;
decklinksink->video_seqnum = gst_event_get_seqnum (event);
{
GstMessage *message;
message = gst_message_new_eos (GST_OBJECT_CAST (decklinksink));
gst_message_set_seqnum (message, decklinksink->video_seqnum);
gst_element_post_message (GST_ELEMENT_CAST (decklinksink), message);
}
res = gst_pad_event_default (pad, parent, event);
break;
default:
res = gst_pad_event_default (pad, parent, event);
break;
}
return res;
}
static gboolean
gst_decklink_sink_videosink_query (GstPad * pad, GstObject * parent,
GstQuery * query)
{
gboolean res;
GstDecklinkSink *decklinksink;
decklinksink = GST_DECKLINK_SINK (parent);
GST_DEBUG_OBJECT (decklinksink, "query");
switch (GST_QUERY_TYPE (query)) {
case GST_QUERY_CAPS:{
GstCaps *mode_caps, *filter, *caps;
/* FIXME: do we change mode if incoming caps change? If yes, we
* should probably return the template caps instead */
mode_caps = gst_decklink_mode_get_caps (decklinksink->mode);
gst_query_parse_caps (query, &filter);
if (filter) {
caps =
gst_caps_intersect_full (filter, mode_caps,
GST_CAPS_INTERSECT_FIRST);
gst_caps_unref (mode_caps);
} else {
caps = mode_caps;
}
gst_query_set_caps_result (query, caps);
gst_caps_unref (caps);
res = TRUE;
break;
}
default:
res = gst_pad_query_default (pad, parent, query);
break;
}
return res;
}
static GstFlowReturn
gst_decklink_sink_audiosink_chain (GstPad * pad, GstObject * parent,
GstBuffer * buffer)
{
GstDecklinkSink *decklinksink;
GstFlowReturn ret;
decklinksink = GST_DECKLINK_SINK (parent);
if (decklinksink->stop)
return GST_FLOW_FLUSHING;
g_mutex_lock (&decklinksink->audio_mutex);
while (!decklinksink->stop &&
gst_adapter_available (decklinksink->audio_adapter) > 1600 * 4 * 2) {
g_cond_wait (&decklinksink->audio_cond, &decklinksink->audio_mutex);
}
gst_adapter_push (decklinksink->audio_adapter, buffer);
g_mutex_unlock (&decklinksink->audio_mutex);
ret = GST_FLOW_OK;
return ret;
}
static gboolean
gst_decklink_sink_audiosink_event (GstPad * pad, GstObject * parent,
GstEvent * event)
{
gboolean res;
GstDecklinkSink *decklinksink;
decklinksink = GST_DECKLINK_SINK (parent);
GST_DEBUG_OBJECT (pad, "event: %" GST_PTR_FORMAT, event);
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_EOS:
/* FIXME: EOS aggregation with video pad looks wrong */
decklinksink->audio_eos = TRUE;
decklinksink->audio_seqnum = gst_event_get_seqnum (event);
res = gst_pad_event_default (pad, parent, event);
break;
default:
res = gst_pad_event_default (pad, parent, event);
break;
}
return res;
}
static gboolean
gst_decklink_sink_audiosink_query (GstPad * pad, GstObject * parent,
GstQuery * query)
{
gboolean res;
GST_DEBUG_OBJECT (pad, "query: %" GST_PTR_FORMAT, query);
switch (GST_QUERY_TYPE (query)) {
default:
res = gst_pad_query_default (pad, parent, query);
break;
}
return res;
}
HRESULT
Output::ScheduledFrameCompleted (IDeckLinkVideoFrame * completedFrame,
BMDOutputFrameCompletionResult result)
{
GST_DEBUG ("ScheduledFrameCompleted");
g_mutex_lock (&decklinksink->mutex);
g_cond_signal (&decklinksink->cond);
decklinksink->queued_frames--;
g_mutex_unlock (&decklinksink->mutex);
return S_OK;
}
HRESULT
Output::ScheduledPlaybackHasStopped ()
{
GST_DEBUG ("ScheduledPlaybackHasStopped");
return S_OK;
}
HRESULT
Output::RenderAudioSamples (bool preroll)
{
uint32_t samplesWritten;
HRESULT ret;
// guint64 samplesToWrite;
if (decklinksink->stop) {
GST_DEBUG ("decklinksink->stop set TRUE!");
decklinksink->output->BeginAudioPreroll ();
// running = true;
} else {
gconstpointer data;
int n;
g_mutex_lock (&decklinksink->audio_mutex);
n = gst_adapter_available (decklinksink->audio_adapter);
if (n > 0) {
data = gst_adapter_map (decklinksink->audio_adapter, n);
ret = decklinksink->output->ScheduleAudioSamples ((void *) data, n / 4,
0, 0, &samplesWritten);
gst_adapter_unmap (decklinksink->audio_adapter);
gst_adapter_flush (decklinksink->audio_adapter, samplesWritten * 4);
if (ret != S_OK) {
GST_ELEMENT_ERROR (decklinksink, STREAM, FAILED,
(NULL), ("Failed to schedule audio samples: 0x%08x", ret));
} else {
GST_DEBUG ("wrote %d samples, %d available", samplesWritten, n / 4);
}
g_cond_signal (&decklinksink->audio_cond);
} else {
if (decklinksink->audio_eos) {
GstMessage *message;
message = gst_message_new_eos (GST_OBJECT_CAST (decklinksink));
gst_message_set_seqnum (message, decklinksink->audio_seqnum);
gst_element_post_message (GST_ELEMENT_CAST (decklinksink), message);
}
}
g_mutex_unlock (&decklinksink->audio_mutex);
}
GST_DEBUG ("RenderAudioSamples");
return S_OK;
}