自学教程：C++ GST_DECKLINK_SRC函数代码示例

static gbooleangst_decklink_src_stop (GstElement * element){  GstDecklinkSrc *decklinksrc = GST_DECKLINK_SRC (element);  gst_task_stop (decklinksrc->task);  g_mutex_lock (&decklinksrc->mutex);  decklinksrc->stop = TRUE;  g_cond_signal (&decklinksrc->cond);  g_mutex_unlock (&decklinksrc->mutex);  gst_task_join (decklinksrc->task);  decklinksrc->input->StopStreams ();  decklinksrc->input->DisableVideoInput ();  decklinksrc->input->DisableAudioInput ();  g_list_free_full (decklinksrc->pending_events,      (GDestroyNotify) gst_mini_object_unref);  decklinksrc->pending_events = NULL;  decklinksrc->have_events = FALSE;  decklinksrc->pending_eos = FALSE;  return TRUE;}

voidgst_decklink_src_finalize (GObject * object){  GstDecklinkSrc *decklinksrc;  g_return_if_fail (GST_IS_DECKLINK_SRC (object));  decklinksrc = GST_DECKLINK_SRC (object);  /* clean up object here */  g_cond_clear (&decklinksrc->cond);  g_mutex_clear (&decklinksrc->mutex);  gst_task_set_lock (decklinksrc->task, NULL);  g_object_unref (decklinksrc->task);#ifdef _MSC_VER  /* signal the COM thread that it should uninitialize COM */  if (decklinksrc->comInitialized) {    g_mutex_lock (&decklinksrc->com_deinit_lock);    g_cond_signal (&decklinksrc->com_uninitialize);    g_cond_wait (&decklinksrc->com_uninitialized, &decklinksrc->com_deinit_lock);    g_mutex_unlock (&decklinksrc->com_deinit_lock);  }  g_mutex_clear (&decklinksrc->com_init_lock);  g_mutex_clear (&decklinksrc->com_deinit_lock);  g_cond_clear (&decklinksrc->com_initialized);  g_cond_clear (&decklinksrc->com_uninitialize);  g_cond_clear (&decklinksrc->com_uninitialized);#endif /* _MSC_VER */  g_rec_mutex_clear (&decklinksrc->task_mutex);  G_OBJECT_CLASS (parent_class)->finalize (object);}

static gbooleangst_decklink_src_stop (GstElement * element){  GstDecklinkSrc *decklinksrc = GST_DECKLINK_SRC (element);  gst_task_stop (decklinksrc->task);  g_mutex_lock (decklinksrc->mutex);  decklinksrc->stop = TRUE;  g_cond_signal (decklinksrc->cond);  g_mutex_unlock (decklinksrc->mutex);  gst_task_join (decklinksrc->task);  decklinksrc->input->StopStreams ();  decklinksrc->input->DisableVideoInput ();  decklinksrc->input->DisableAudioInput ();  decklinksrc->input->Release ();  decklinksrc->input = NULL;  decklinksrc->decklink->Release ();  decklinksrc->decklink = NULL;  return TRUE;}

voidgst_decklink_src_get_property (GObject * object, guint property_id,                               GValue * value, GParamSpec * pspec){    GstDecklinkSrc *decklinksrc;    g_return_if_fail (GST_IS_DECKLINK_SRC (object));    decklinksrc = GST_DECKLINK_SRC (object);    switch (property_id) {    case PROP_MODE:        g_value_set_enum (value, decklinksrc->mode);        break;    case PROP_CONNECTION:        g_value_set_enum (value, decklinksrc->connection);        break;    case PROP_AUDIO_INPUT:        g_value_set_enum (value, decklinksrc->audio_connection);        break;    case PROP_SUBDEVICE:        g_value_set_int (value, decklinksrc->subdevice);        break;    default:        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);        break;    }}

voidgst_decklink_src_set_property (GObject * object, guint property_id,    const GValue * value, GParamSpec * pspec){  GstDecklinkSrc *decklinksrc;  decklinksrc = GST_DECKLINK_SRC (object);  switch (property_id) {    case PROP_MODE:      decklinksrc->mode = (GstDecklinkModeEnum) g_value_get_enum (value);      break;    case PROP_CONNECTION:      decklinksrc->connection =          (GstDecklinkConnectionEnum) g_value_get_enum (value);      break;    case PROP_AUDIO_INPUT:      decklinksrc->audio_connection =          (GstDecklinkAudioConnectionEnum) g_value_get_enum (value);      break;    case PROP_DEVICE:      decklinksrc->device = g_value_get_int (value);      break;    default:      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);      break;  }}

static voidgst_decklink_src_audio_src_fixatecaps (GstPad * pad, GstCaps * caps){    GstDecklinkSrc *decklinksrc;    decklinksrc = GST_DECKLINK_SRC (gst_pad_get_parent (pad));    GST_DEBUG_OBJECT (decklinksrc, "fixatecaps");    gst_object_unref (decklinksrc);}

static gbooleangst_decklink_src_audio_src_activatepull (GstPad * pad, gboolean active){  GstDecklinkSrc *decklinksrc;  decklinksrc = GST_DECKLINK_SRC (gst_pad_get_parent (pad));  GST_DEBUG_OBJECT (decklinksrc, "activatepull");  gst_object_unref (decklinksrc);  return FALSE;}

HRESULT    DeckLinkCaptureDelegate::VideoInputFrameArrived (IDeckLinkVideoInputFrame *    videoFrame, IDeckLinkAudioInputPacket * audioFrame){  GstDecklinkSrc *decklinksrc;  g_return_val_if_fail (priv != NULL, S_OK);  g_return_val_if_fail (GST_IS_DECKLINK_SRC (priv), S_OK);  decklinksrc = GST_DECKLINK_SRC (priv);  // Handle Video Frame  if (videoFrame) {    if (videoFrame->GetFlags () & bmdFrameHasNoInputSource) {      GST_DEBUG ("Frame received - No input signal detected");    } else {      const char *timecodeString = NULL;      if (g_timecodeFormat != 0) {        IDeckLinkTimecode *timecode;        if (videoFrame->GetTimecode (g_timecodeFormat, &timecode) == S_OK) {          timecode->GetString (&timecodeString);          CONVERT_COM_STRING (timecodeString);        }      }      GST_DEBUG ("Frame received [%s] - %s - Size: %li bytes",          timecodeString != NULL ? timecodeString : "No timecode",          "Valid Frame", videoFrame->GetRowBytes () * videoFrame->GetHeight ());      if (timecodeString)        FREE_COM_STRING (timecodeString);      g_mutex_lock (decklinksrc->mutex);      if (decklinksrc->video_frame != NULL) {        decklinksrc->dropped_frames++;      } else {        videoFrame->AddRef ();        decklinksrc->video_frame = videoFrame;        if (audioFrame) {          audioFrame->AddRef ();          decklinksrc->audio_frame = audioFrame;        }      }      /* increment regardless whether frame was dropped or not */      decklinksrc->frame_num++;      g_cond_signal (decklinksrc->cond);      g_mutex_unlock (decklinksrc->mutex);    }  }  return S_OK;}

/* events sent to this element directly, mainly from the application */static gbooleangst_decklink_src_send_event (GstElement * element, GstEvent * event){  GstDecklinkSrc *src;  gboolean result = FALSE;  src = GST_DECKLINK_SRC (element);  GST_DEBUG_OBJECT (src, "handling event %p %" GST_PTR_FORMAT, event, event);  switch (GST_EVENT_TYPE (event)) {    case GST_EVENT_EOS:      g_atomic_int_set (&src->pending_eos, TRUE);      GST_INFO_OBJECT (src, "EOS pending");      result = TRUE;      break;      break;    case GST_EVENT_TAG:    case GST_EVENT_CUSTOM_DOWNSTREAM:    case GST_EVENT_CUSTOM_BOTH:      /* Insert TAG, CUSTOM_DOWNSTREAM, CUSTOM_BOTH in the dataflow */      GST_OBJECT_LOCK (src);      src->pending_events = g_list_append (src->pending_events, event);      g_atomic_int_set (&src->have_events, TRUE);      GST_OBJECT_UNLOCK (src);      event = NULL;      result = TRUE;      break;    case GST_EVENT_CUSTOM_DOWNSTREAM_OOB:    case GST_EVENT_CUSTOM_BOTH_OOB:      /* insert a random custom event into the pipeline */      GST_DEBUG_OBJECT (src, "pushing custom OOB event downstream");      result = gst_pad_push_event (src->videosrcpad, gst_event_ref (event));      result |= gst_pad_push_event (src->audiosrcpad, event);      /* we gave away the ref to the event in the push */      event = NULL;      break;    case GST_EVENT_CUSTOM_UPSTREAM:      /* drop */    case GST_EVENT_SEGMENT:      /* sending random SEGMENT downstream can break sync - drop */    default:      GST_LOG_OBJECT (src, "dropping %s event", GST_EVENT_TYPE_NAME (event));      break;  }  /* if we still have a ref to the event, unref it now */  if (event)    gst_event_unref (event);  return result;}

static gbooleangst_decklink_src_video_src_acceptcaps (GstPad * pad, GstCaps * caps){    GstDecklinkSrc *decklinksrc;    decklinksrc = GST_DECKLINK_SRC (gst_pad_get_parent (pad));    GST_DEBUG_OBJECT (decklinksrc, "acceptcaps");    gst_object_unref (decklinksrc);    return TRUE;}

static GstPadLinkReturngst_decklink_src_audio_src_link (GstPad * pad, GstPad * peer){    GstDecklinkSrc *decklinksrc;    decklinksrc = GST_DECKLINK_SRC (gst_pad_get_parent (pad));    GST_DEBUG_OBJECT (decklinksrc, "link");    gst_object_unref (decklinksrc);    return GST_PAD_LINK_OK;}

static gbooleangst_decklink_src_video_src_query (GstPad * pad, GstObject * parent,    GstQuery * query){  GstDecklinkSrc *decklinksrc;  gboolean ret = FALSE;  decklinksrc = GST_DECKLINK_SRC (parent);  GST_DEBUG_OBJECT (pad, "query: %" GST_PTR_FORMAT, query);  switch (GST_QUERY_TYPE (query)) {    case GST_QUERY_LATENCY:{      GstClockTime min_latency, max_latency;      const GstDecklinkMode *mode;      /* device must be open */      if (decklinksrc->decklink == NULL) {        GST_WARNING_OBJECT (decklinksrc,            "Can't give latency since device isn't open !");        goto done;      }      mode = gst_decklink_get_mode (decklinksrc->mode);      /* min latency is the time to capture one frame */      min_latency =          gst_util_uint64_scale_int (GST_SECOND, mode->fps_d, mode->fps_n);      /* max latency is total duration of the frame buffer */      max_latency = 2 * min_latency;      GST_DEBUG_OBJECT (decklinksrc,          "report latency min %" GST_TIME_FORMAT " max %" GST_TIME_FORMAT,          GST_TIME_ARGS (min_latency), GST_TIME_ARGS (max_latency));      /* we are always live, the min latency is 1 frame and the max latency is       * the complete buffer of frames. */      gst_query_set_latency (query, TRUE, min_latency, max_latency);      ret = TRUE;      break;    }    default:      ret = gst_pad_query_default (pad, parent, query);      break;  }done:  return ret;}

static GstFlowReturngst_decklink_src_audio_src_getrange (GstPad * pad, guint64 offset, guint length,                                     GstBuffer ** buffer){    GstDecklinkSrc *decklinksrc;    decklinksrc = GST_DECKLINK_SRC (gst_pad_get_parent (pad));    GST_DEBUG_OBJECT (decklinksrc, "getrange");    gst_object_unref (decklinksrc);    return GST_FLOW_OK;}

static GstCaps *gst_decklink_src_audio_src_getcaps (GstPad * pad){    GstDecklinkSrc *decklinksrc;    GstCaps *caps;    decklinksrc = GST_DECKLINK_SRC (gst_pad_get_parent (pad));    GST_DEBUG_OBJECT (decklinksrc, "getcaps");    caps = gst_caps_copy (gst_pad_get_pad_template_caps (pad));    gst_object_unref (decklinksrc);    return caps;}

static GstIterator *gst_decklink_src_audio_src_iterintlink (GstPad * pad){    GstDecklinkSrc *decklinksrc;    GstIterator *iter;    decklinksrc = GST_DECKLINK_SRC (gst_pad_get_parent (pad));    GST_DEBUG_OBJECT (decklinksrc, "iterintlink");    iter = gst_pad_iterate_internal_links_default (pad);    gst_object_unref (decklinksrc);    return iter;}

static GstCaps *gst_decklink_src_video_src_getcaps (GstPad * pad){    GstDecklinkSrc *decklinksrc;    GstCaps *caps;    decklinksrc = GST_DECKLINK_SRC (gst_pad_get_parent (pad));    GST_DEBUG_OBJECT (decklinksrc, "getcaps");    caps = gst_decklink_mode_get_caps (decklinksrc->mode);    gst_object_unref (decklinksrc);    return caps;}

HRESULTDeckLinkCaptureDelegate::VideoInputFormatChanged (    BMDVideoInputFormatChangedEvents events, IDeckLinkDisplayMode * mode,    BMDDetectedVideoInputFormatFlags){  GstDecklinkSrc *decklinksrc;  g_return_val_if_fail (priv != NULL, S_OK);  g_return_val_if_fail (GST_IS_DECKLINK_SRC (priv), S_OK);  decklinksrc = GST_DECKLINK_SRC (priv);  GST_ERROR_OBJECT (decklinksrc, "unimplemented: video input format changed");  return S_OK;}

static gbooleangst_decklink_src_query (GstElement * element, GstQuery * query){  GstDecklinkSrc *decklinksrc = GST_DECKLINK_SRC (element);  gboolean ret;  GST_DEBUG_OBJECT (decklinksrc, "query");  switch (GST_QUERY_TYPE (query)) {    default:      ret = GST_ELEMENT_CLASS (parent_class)->query (element, query);      break;  }  return ret;}

static gbooleangst_decklink_src_audio_src_acceptcaps (GstPad * pad, GstCaps * caps){  GstDecklinkSrc *decklinksrc;  GstCaps *pad_caps;  gboolean can_intersect;  decklinksrc = GST_DECKLINK_SRC (gst_pad_get_parent (pad));  pad_caps = gst_pad_get_caps_reffed (pad);  can_intersect = gst_caps_can_intersect (pad_caps, caps);  gst_caps_unref (pad_caps);  GST_DEBUG_OBJECT (decklinksrc, "acceptcaps");  gst_object_unref (decklinksrc);  return can_intersect;}

static gbooleangst_decklink_src_video_src_setcaps (GstPad * pad, GstCaps * caps){  GstDecklinkSrc *decklinksrc;  GstCaps *mode_caps;  gboolean can_intersect;  decklinksrc = GST_DECKLINK_SRC (gst_pad_get_parent (pad));  GST_DEBUG_OBJECT (decklinksrc, "setcaps");  mode_caps = gst_decklink_mode_get_caps (decklinksrc->mode);  can_intersect = gst_caps_can_intersect (mode_caps, caps);  gst_caps_unref (mode_caps);  gst_object_unref (decklinksrc);  return can_intersect;}

HRESULTDeckLinkCaptureDelegate::VideoInputFrameArrived (IDeckLinkVideoInputFrame *    videoFrame, IDeckLinkAudioInputPacket * audioFrame){  GstDecklinkSrc *decklinksrc = GST_DECKLINK_SRC (priv);  // Handle Video Frame  if (videoFrame) {    if (videoFrame->GetFlags () & bmdFrameHasNoInputSource) {      GST_DEBUG("Frame received - No input signal detected");    } else {      const char *timecodeString = NULL;      if (g_timecodeFormat != 0) {        IDeckLinkTimecode *timecode;        if (videoFrame->GetTimecode (g_timecodeFormat, &timecode) == S_OK) {          timecode->GetString (&timecodeString);        }      }      GST_DEBUG("Frame received [%s] - %s - Size: %li bytes",          timecodeString != NULL ? timecodeString : "No timecode",          "Valid Frame",          videoFrame->GetRowBytes () * videoFrame->GetHeight ());      if (timecodeString)        free ((void *) timecodeString);      g_mutex_lock (decklinksrc->mutex);      if (decklinksrc->video_frame != NULL) {        decklinksrc->dropped_frames++;      } else {        videoFrame->AddRef();        decklinksrc->video_frame = videoFrame;        if (audioFrame) {          audioFrame->AddRef();          decklinksrc->audio_frame = audioFrame;        }      }      g_cond_signal (decklinksrc->cond);      g_mutex_unlock (decklinksrc->mutex);    }  }  return S_OK;}

static gbooleangst_decklink_src_audio_src_query (GstPad * pad, GstQuery * query){    gboolean res;    GstDecklinkSrc *decklinksrc;    decklinksrc = GST_DECKLINK_SRC (gst_pad_get_parent (pad));    GST_DEBUG_OBJECT (decklinksrc, "query");    switch (GST_QUERY_TYPE (query)) {    default:        res = gst_pad_query_default (pad, query);        break;    }    gst_object_unref (decklinksrc);    return res;}

static gbooleangst_decklink_src_audio_src_event (GstPad * pad, GstEvent * event){    gboolean res;    GstDecklinkSrc *decklinksrc;    decklinksrc = GST_DECKLINK_SRC (gst_pad_get_parent (pad));    GST_DEBUG_OBJECT (decklinksrc, "event");    switch (GST_EVENT_TYPE (event)) {    default:        res = gst_pad_event_default (pad, event);        break;    }    gst_object_unref (decklinksrc);    return res;}

static gbooleangst_decklink_src_audio_src_activate (GstPad * pad){    GstDecklinkSrc *decklinksrc;    gboolean ret;    decklinksrc = GST_DECKLINK_SRC (gst_pad_get_parent (pad));    GST_DEBUG_OBJECT (decklinksrc, "activate");    if (gst_pad_check_pull_range (pad)) {        GST_DEBUG_OBJECT (pad, "activating pull");        ret = gst_pad_activate_pull (pad, TRUE);    } else {        GST_DEBUG_OBJECT (pad, "activating push");        ret = gst_pad_activate_push (pad, TRUE);    }    gst_object_unref (decklinksrc);    return ret;}

static voidgst_decklink_src_task (void *priv){  GstDecklinkSrc *decklinksrc = GST_DECKLINK_SRC (priv);  GstBuffer *buffer;  GstBuffer *audio_buffer;  IDeckLinkVideoInputFrame *video_frame;  IDeckLinkAudioInputPacket *audio_frame;  void *data;  gsize data_size;  int n_samples;  GstFlowReturn ret;  const GstDecklinkMode *mode;  gboolean discont = FALSE;  GST_DEBUG_OBJECT (decklinksrc, "task");  g_mutex_lock (&decklinksrc->mutex);  while (decklinksrc->video_frame == NULL && !decklinksrc->stop) {    g_cond_wait (&decklinksrc->cond, &decklinksrc->mutex);  }  video_frame = decklinksrc->video_frame;  audio_frame = decklinksrc->audio_frame;  decklinksrc->video_frame = NULL;  decklinksrc->audio_frame = NULL;  g_mutex_unlock (&decklinksrc->mutex);  if (decklinksrc->stop) {    if (video_frame)      video_frame->Release ();    if (audio_frame)      audio_frame->Release ();    GST_DEBUG ("stopping task");    return;  }  /* warning on dropped frames */  /* FIXME: post QoS message */  if (decklinksrc->dropped_frames - decklinksrc->dropped_frames_old > 0) {    GST_ELEMENT_WARNING (decklinksrc, RESOURCE, READ,        ("Dropped %d frame(s), for a total of %d frame(s)",            decklinksrc->dropped_frames - decklinksrc->dropped_frames_old,            decklinksrc->dropped_frames), (NULL));    decklinksrc->dropped_frames_old = decklinksrc->dropped_frames;    /* FIXME: discont = TRUE; ? */  }  if (!decklinksrc->started) {    gst_decklink_src_send_initial_events (decklinksrc);    decklinksrc->started = TRUE;  }  mode = gst_decklink_get_mode (decklinksrc->mode);  video_frame->GetBytes (&data);  data_size = mode->width * mode->height * 2;  if (decklinksrc->copy_data) {    buffer = gst_buffer_new_and_alloc (data_size);    gst_buffer_fill (buffer, 0, data, data_size);    video_frame->Release ();  } else {    VideoFrame *vf;    vf = (VideoFrame *) g_malloc0 (sizeof (VideoFrame));    buffer = gst_buffer_new_wrapped_full ((GstMemoryFlags) 0, data, data_size,        0, data_size, vf, (GDestroyNotify) video_frame_free);    vf->frame = video_frame;    vf->input = decklinksrc->input;    vf->input->AddRef ();  }  GST_BUFFER_TIMESTAMP (buffer) =      gst_util_uint64_scale_int (decklinksrc->frame_num * GST_SECOND,      mode->fps_d, mode->fps_n);  GST_BUFFER_DURATION (buffer) =      gst_util_uint64_scale_int ((decklinksrc->frame_num + 1) * GST_SECOND,      mode->fps_d, mode->fps_n) - GST_BUFFER_TIMESTAMP (buffer);  GST_BUFFER_OFFSET (buffer) = decklinksrc->frame_num;  GST_BUFFER_OFFSET_END (buffer) = decklinksrc->frame_num; /* FIXME: +1? */  /* FIXME: set video meta */  if (decklinksrc->frame_num == 0)    discont = TRUE;  if (discont)    GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_DISCONT);  else    GST_BUFFER_FLAG_UNSET (buffer, GST_BUFFER_FLAG_DISCONT);  /* FIXME: proper flow aggregation with audio flow */  ret = gst_pad_push (decklinksrc->videosrcpad, buffer);  if (!(ret == GST_FLOW_OK || ret == GST_FLOW_NOT_LINKED ||          ret == GST_FLOW_FLUSHING)) {//.........这里部分代码省略.........

/* FIXME: post error messages for the misc. failures */static gbooleangst_decklink_src_start (GstElement * element){  GstDecklinkSrc *decklinksrc = GST_DECKLINK_SRC (element);  DeckLinkCaptureDelegate *delegate;  BMDAudioSampleType sample_depth;  int channels;  HRESULT ret;  const GstDecklinkMode *mode;  IDeckLinkConfiguration *config;  BMDVideoConnection conn;  BMDAudioConnection aconn;  GST_DEBUG_OBJECT (decklinksrc, "start");  decklinksrc->decklink = gst_decklink_get_nth_device (decklinksrc->device);  if (decklinksrc->decklink == NULL) {    return FALSE;  }  decklinksrc->input = gst_decklink_get_nth_input (decklinksrc->device);  delegate = new DeckLinkCaptureDelegate ();  delegate->priv = decklinksrc;  ret = decklinksrc->input->SetCallback (delegate);  if (ret != S_OK) {    GST_ERROR ("set callback failed (input source)");    return FALSE;  }  decklinksrc->config = gst_decklink_get_nth_config (decklinksrc->device);  config = decklinksrc->config;  switch (decklinksrc->connection) {    default:    case GST_DECKLINK_CONNECTION_SDI:      conn = bmdVideoConnectionSDI;      aconn = bmdAudioConnectionEmbedded;      break;    case GST_DECKLINK_CONNECTION_HDMI:      conn = bmdVideoConnectionHDMI;      aconn = bmdAudioConnectionEmbedded;      break;    case GST_DECKLINK_CONNECTION_OPTICAL_SDI:      conn = bmdVideoConnectionOpticalSDI;      aconn = bmdAudioConnectionEmbedded;      break;    case GST_DECKLINK_CONNECTION_COMPONENT:      conn = bmdVideoConnectionComponent;      aconn = bmdAudioConnectionAnalog;      break;    case GST_DECKLINK_CONNECTION_COMPOSITE:      conn = bmdVideoConnectionComposite;      aconn = bmdAudioConnectionAnalog;      break;    case GST_DECKLINK_CONNECTION_SVIDEO:      conn = bmdVideoConnectionSVideo;      aconn = bmdAudioConnectionAnalog;      break;  }  ret = config->SetInt (bmdDeckLinkConfigVideoInputConnection, conn);  if (ret != S_OK) {    GST_ERROR ("set configuration (input source)");    return FALSE;  }  if (decklinksrc->connection == GST_DECKLINK_CONNECTION_COMPOSITE) {    ret = config->SetInt (bmdDeckLinkConfigAnalogVideoInputFlags,        bmdAnalogVideoFlagCompositeSetup75);    if (ret != S_OK) {      GST_ERROR ("set configuration (composite setup)");      return FALSE;    }  }  switch (decklinksrc->audio_connection) {    default:    case GST_DECKLINK_AUDIO_CONNECTION_AUTO:      /* set above */      break;    case GST_DECKLINK_AUDIO_CONNECTION_EMBEDDED:      aconn = bmdAudioConnectionEmbedded;      break;    case GST_DECKLINK_AUDIO_CONNECTION_AES_EBU:      aconn = bmdAudioConnectionAESEBU;      break;    case GST_DECKLINK_AUDIO_CONNECTION_ANALOG:      aconn = bmdAudioConnectionAnalog;      break;  }  ret = config->SetInt (bmdDeckLinkConfigAudioInputConnection, aconn);  if (ret != S_OK) {    GST_ERROR ("set configuration (audio input connection)");    return FALSE;  }  mode = gst_decklink_get_mode (decklinksrc->mode);//.........这里部分代码省略.........

static voidgst_decklink_src_task (void *priv){    GstDecklinkSrc *decklinksrc = GST_DECKLINK_SRC (priv);    GstBuffer *buffer;    GstBuffer *audio_buffer;    IDeckLinkVideoInputFrame *video_frame;    IDeckLinkAudioInputPacket *audio_frame;    void *data;    int n_samples;    GstFlowReturn ret;    const GstDecklinkMode *mode;    GST_DEBUG_OBJECT (decklinksrc, "task");    g_mutex_lock (decklinksrc->mutex);    while (decklinksrc->video_frame == NULL && !decklinksrc->stop) {        g_cond_wait (decklinksrc->cond, decklinksrc->mutex);    }    video_frame = decklinksrc->video_frame;    audio_frame = decklinksrc->audio_frame;    decklinksrc->video_frame = NULL;    decklinksrc->audio_frame = NULL;    g_mutex_unlock (decklinksrc->mutex);    if (decklinksrc->stop) {        GST_DEBUG ("stopping task");        return;    }    /* warning on dropped frames */    if (decklinksrc->dropped_frames - decklinksrc->dropped_frames_old > 0) {        GST_ELEMENT_WARNING (decklinksrc, RESOURCE, READ,                             ("Dropped %d frame(s), for a total of %d frame(s)",                              decklinksrc->dropped_frames - decklinksrc->dropped_frames_old,                              decklinksrc->dropped_frames),                             (NULL));        decklinksrc->dropped_frames_old = decklinksrc->dropped_frames;    }    mode = gst_decklink_get_mode (decklinksrc->mode);    video_frame->GetBytes (&data);    if (decklinksrc->copy_data) {        buffer = gst_buffer_new_and_alloc (mode->width * mode->height * 2);        memcpy (GST_BUFFER_DATA (buffer), data, mode->width * mode->height * 2);        video_frame->Release ();    } else {        buffer = gst_buffer_new ();        GST_BUFFER_SIZE (buffer) = mode->width * mode->height * 2;        GST_BUFFER_DATA (buffer) = (guint8 *) data;        GST_BUFFER_FREE_FUNC (buffer) = video_frame_free;        GST_BUFFER_MALLOCDATA (buffer) = (guint8 *) video_frame;    }    GST_BUFFER_TIMESTAMP (buffer) =        gst_util_uint64_scale_int (decklinksrc->frame_num * GST_SECOND,                                   mode->fps_d, mode->fps_n);    GST_BUFFER_DURATION (buffer) =        gst_util_uint64_scale_int ((decklinksrc->frame_num + 1) * GST_SECOND,                                   mode->fps_d, mode->fps_n) - GST_BUFFER_TIMESTAMP (buffer);    GST_BUFFER_OFFSET (buffer) = decklinksrc->frame_num;    GST_BUFFER_OFFSET_END (buffer) = decklinksrc->frame_num;    if (decklinksrc->frame_num == 0) {        GstEvent *event;        gboolean ret;        GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_DISCONT);        event = gst_event_new_new_segment (FALSE, 1.0, GST_FORMAT_TIME, 0,                                           GST_CLOCK_TIME_NONE, 0);        ret = gst_pad_push_event (decklinksrc->videosrcpad, event);        if (!ret) {            GST_ERROR_OBJECT (decklinksrc, "new segment event ret=%d", ret);            return;        }    }    if (decklinksrc->video_caps == NULL) {        decklinksrc->video_caps = gst_decklink_mode_get_caps (decklinksrc->mode);    }    gst_buffer_set_caps (buffer, decklinksrc->video_caps);    ret = gst_pad_push (decklinksrc->videosrcpad, buffer);    if (ret != GST_FLOW_OK) {        GST_ELEMENT_ERROR (decklinksrc, CORE, NEGOTIATION, (NULL), (NULL));    }    if (gst_pad_is_linked (decklinksrc->audiosrcpad)) {        n_samples = audio_frame->GetSampleFrameCount ();        audio_frame->GetBytes (&data);        audio_buffer = gst_buffer_new_and_alloc (n_samples * 2 * 2);        memcpy (GST_BUFFER_DATA (audio_buffer), data, n_samples * 2 * 2);        GST_BUFFER_TIMESTAMP (audio_buffer) =//.........这里部分代码省略.........

static gbooleangst_decklink_src_start (GstElement * element){    GstDecklinkSrc *decklinksrc = GST_DECKLINK_SRC (element);    IDeckLinkIterator *iterator;    DeckLinkCaptureDelegate *delegate;    //IDeckLinkDisplayModeIterator *mode_iterator;    //IDeckLinkDisplayMode *mode;    BMDAudioSampleType sample_depth;    int channels;    HRESULT ret;    const GstDecklinkMode *mode;    IDeckLinkConfiguration *config;    BMDVideoConnection conn;    BMDAudioConnection aconn;    int i;    GST_DEBUG_OBJECT (decklinksrc, "start");    iterator = CreateDeckLinkIteratorInstance ();    if (iterator == NULL) {        GST_ERROR ("no driver");        return FALSE;    }    ret = iterator->Next (&decklinksrc->decklink);    if (ret != S_OK) {        GST_ERROR ("no card");        return FALSE;    }    for (i = 0; i < decklinksrc->subdevice; i++) {        ret = iterator->Next (&decklinksrc->decklink);        if (ret != S_OK) {            GST_ERROR ("no card");            return FALSE;        }    }    ret = decklinksrc->decklink->QueryInterface (IID_IDeckLinkInput,            (void **) &decklinksrc->input);    if (ret != S_OK) {        GST_ERROR ("query interface failed");        return FALSE;    }    delegate = new DeckLinkCaptureDelegate ();    delegate->priv = decklinksrc;    decklinksrc->input->SetCallback (delegate);    ret = decklinksrc->decklink->QueryInterface (IID_IDeckLinkConfiguration,            (void **) &config);    if (ret != S_OK) {        GST_ERROR ("query interface failed");        return FALSE;    }    switch (decklinksrc->connection) {    default:    case GST_DECKLINK_CONNECTION_SDI:        conn = bmdVideoConnectionSDI;        aconn = bmdAudioConnectionEmbedded;        break;    case GST_DECKLINK_CONNECTION_HDMI:        conn = bmdVideoConnectionHDMI;        aconn = bmdAudioConnectionEmbedded;        break;    case GST_DECKLINK_CONNECTION_OPTICAL_SDI:        conn = bmdVideoConnectionOpticalSDI;        aconn = bmdAudioConnectionEmbedded;        break;    case GST_DECKLINK_CONNECTION_COMPONENT:        conn = bmdVideoConnectionComponent;        aconn = bmdAudioConnectionAnalog;        break;    case GST_DECKLINK_CONNECTION_COMPOSITE:        conn = bmdVideoConnectionComposite;        aconn = bmdAudioConnectionAnalog;        break;    case GST_DECKLINK_CONNECTION_SVIDEO:        conn = bmdVideoConnectionSVideo;        aconn = bmdAudioConnectionAnalog;        break;    }    ret = config->SetInt (bmdDeckLinkConfigVideoInputConnection, conn);    if (ret != S_OK) {        GST_ERROR ("set configuration (input source)");        return FALSE;    }    if (decklinksrc->connection == GST_DECKLINK_CONNECTION_COMPOSITE) {        ret = config->SetInt (bmdDeckLinkConfigAnalogVideoInputFlags,                              bmdAnalogVideoFlagCompositeSetup75);        if (ret != S_OK) {            GST_ERROR ("set configuration (composite setup)");            return FALSE;        }    }    switch (decklinksrc->audio_connection) {//.........这里部分代码省略.........