C++ GST_BASE_SRC_CLASS函数代码示例

static void
gst_rtmp_src_class_init (GstRTMPSrcClass * klass)
{
  GObjectClass *gobject_class;
  GstElementClass *gstelement_class;
  GstBaseSrcClass *gstbasesrc_class;
  GstPushSrcClass *gstpushsrc_class;

  gobject_class = G_OBJECT_CLASS (klass);
  gstelement_class = GST_ELEMENT_CLASS (klass);
  gstbasesrc_class = GST_BASE_SRC_CLASS (klass);
  gstpushsrc_class = GST_PUSH_SRC_CLASS (klass);

  gobject_class->finalize = gst_rtmp_src_finalize;
  gobject_class->set_property = gst_rtmp_src_set_property;
  gobject_class->get_property = gst_rtmp_src_get_property;

  /* properties */
  g_object_class_install_property (gobject_class, PROP_LOCATION,
      g_param_spec_string ("location", "RTMP Location",
          "Location of the RTMP url to read",
          DEFAULT_LOCATION, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  gst_element_class_add_pad_template (gstelement_class,
      gst_static_pad_template_get (&srctemplate));

  gst_element_class_set_static_metadata (gstelement_class,
      "RTMP Source",
      "Source/File",
      "Read RTMP streams",
      "Bastien Nocera <[email protected]>, "
      "Sebastian Dröge <[email protected]>");

  gstbasesrc_class->start = GST_DEBUG_FUNCPTR (gst_rtmp_src_start);
  gstbasesrc_class->stop = GST_DEBUG_FUNCPTR (gst_rtmp_src_stop);
  gstbasesrc_class->is_seekable = GST_DEBUG_FUNCPTR (gst_rtmp_src_is_seekable);
  gstbasesrc_class->prepare_seek_segment =
      GST_DEBUG_FUNCPTR (gst_rtmp_src_prepare_seek_segment);
  gstbasesrc_class->do_seek = GST_DEBUG_FUNCPTR (gst_rtmp_src_do_seek);
  gstpushsrc_class->create = GST_DEBUG_FUNCPTR (gst_rtmp_src_create);
  gstbasesrc_class->query = GST_DEBUG_FUNCPTR (gst_rtmp_src_query);

  GST_DEBUG_CATEGORY_INIT (rtmpsrc_debug, "rtmpsrc", 0, "RTMP Source");
}

static gboolean
gst_ladspa_source_type_query (GstBaseSrc * base, GstQuery * query)
{
  GstLADSPASource *ladspa = GST_LADSPA_SOURCE (base);
  gboolean res = FALSE;

  switch (GST_QUERY_TYPE (query)) {
    case GST_QUERY_CONVERT:
    {
      GstFormat src_fmt, dest_fmt;
      gint64 src_val, dest_val;

      gst_query_parse_convert (query, &src_fmt, &src_val, &dest_fmt, &dest_val);

      if (!gst_audio_info_convert (&ladspa->info, src_fmt, src_val, dest_fmt,
              &dest_val)) {
        GST_DEBUG_OBJECT (ladspa, "query failed");
        return FALSE;
      }

      gst_query_set_convert (query, src_fmt, src_val, dest_fmt, dest_val);
      res = TRUE;
      break;
    }
    case GST_QUERY_SCHEDULING:
    {
      /* if we can operate in pull mode */
      gst_query_set_scheduling (query, GST_SCHEDULING_FLAG_SEEKABLE, 1, -1, 0);
      gst_query_add_scheduling_mode (query, GST_PAD_MODE_PUSH);
      if (ladspa->can_activate_pull)
        gst_query_add_scheduling_mode (query, GST_PAD_MODE_PULL);

      res = TRUE;
      break;
    }
    default:
      res =
          GST_BASE_SRC_CLASS (gst_ladspa_source_type_parent_class)->query
          (base, query);
      break;
  }

  return res;
}

static void
gst_linsys_sdi_src_class_init (GstLinsysSdiSrcClass * klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  GstBaseSrcClass *base_src_class = GST_BASE_SRC_CLASS (klass);

  GST_DEBUG_CATEGORY_INIT (gst_linsys_sdi_src_debug, "linsyssdisrc", 0,
      "FIXME");

  gobject_class->set_property = gst_linsys_sdi_src_set_property;
  gobject_class->get_property = gst_linsys_sdi_src_get_property;
  gobject_class->dispose = gst_linsys_sdi_src_dispose;
  gobject_class->finalize = gst_linsys_sdi_src_finalize;
  base_src_class->get_caps = GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_get_caps);
  base_src_class->set_caps = GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_set_caps);
  if (0)
    base_src_class->negotiate =
        GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_negotiate);
  base_src_class->newsegment =
      GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_newsegment);
  base_src_class->start = GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_start);
  base_src_class->stop = GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_stop);
  base_src_class->get_times = GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_get_times);
  base_src_class->get_size = GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_get_size);
  base_src_class->is_seekable =
      GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_is_seekable);
  base_src_class->unlock = GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_unlock);
  base_src_class->event = GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_event);
  base_src_class->create = GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_create);
  if (0)
    base_src_class->do_seek = GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_do_seek);
  base_src_class->query = GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_query);
  base_src_class->check_get_range =
      GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_check_get_range);
  base_src_class->fixate = GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_fixate);
  base_src_class->unlock_stop =
      GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_unlock_stop);
  base_src_class->prepare_seek_segment =
      GST_DEBUG_FUNCPTR (gst_linsys_sdi_src_prepare_seek_segment);

  g_object_class_install_property (gobject_class, PROP_DEVICE,
      g_param_spec_string ("device", "Device", "device to transmit data on",
          DEFAULT_DEVICE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
}

static void
gst_v4l2src_class_init (GstV4l2SrcClass * klass)
{
  GObjectClass *gobject_class;
  GstElementClass *element_class;
  GstBaseSrcClass *basesrc_class;
  GstPushSrcClass *pushsrc_class;

  gobject_class = G_OBJECT_CLASS (klass);
  element_class = GST_ELEMENT_CLASS (klass);
  basesrc_class = GST_BASE_SRC_CLASS (klass);
  pushsrc_class = GST_PUSH_SRC_CLASS (klass);

  gobject_class->dispose = gst_v4l2src_dispose;
  gobject_class->finalize = (GObjectFinalizeFunc) gst_v4l2src_finalize;
  gobject_class->set_property = gst_v4l2src_set_property;
  gobject_class->get_property = gst_v4l2src_get_property;

  element_class->change_state = gst_v4l2src_change_state;

  gst_v4l2_object_install_properties_helper (gobject_class,
      DEFAULT_PROP_DEVICE);
  g_object_class_install_property (gobject_class, PROP_QUEUE_SIZE,
      g_param_spec_uint ("queue-size", "Queue size",
          "Number of buffers to be enqueud in the driver in streaming mode",
          GST_V4L2_MIN_BUFFERS, GST_V4L2_MAX_BUFFERS, PROP_DEF_QUEUE_SIZE,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
  g_object_class_install_property (gobject_class, PROP_ALWAYS_COPY,
      g_param_spec_boolean ("always-copy", "Always Copy",
          "If the buffer will or not be used directly from mmap",
          PROP_DEF_ALWAYS_COPY, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  basesrc_class->get_caps = GST_DEBUG_FUNCPTR (gst_v4l2src_get_caps);
  basesrc_class->set_caps = GST_DEBUG_FUNCPTR (gst_v4l2src_set_caps);
  basesrc_class->start = GST_DEBUG_FUNCPTR (gst_v4l2src_start);
  basesrc_class->unlock = GST_DEBUG_FUNCPTR (gst_v4l2src_unlock);
  basesrc_class->unlock_stop = GST_DEBUG_FUNCPTR (gst_v4l2src_unlock_stop);
  basesrc_class->stop = GST_DEBUG_FUNCPTR (gst_v4l2src_stop);
  basesrc_class->query = GST_DEBUG_FUNCPTR (gst_v4l2src_query);
  basesrc_class->fixate = GST_DEBUG_FUNCPTR (gst_v4l2src_fixate);
  basesrc_class->negotiate = GST_DEBUG_FUNCPTR (gst_v4l2src_negotiate);

  pushsrc_class->create = GST_DEBUG_FUNCPTR (gst_v4l2src_create);
}

static void
gst_spot_src_class_init (GstSpotSrcClass * klass)
{
  GObjectClass *gobject_class;
  GstBaseSrcClass *gstbasesrc_class;
  gobject_class = G_OBJECT_CLASS (klass);
  gstbasesrc_class = GST_BASE_SRC_CLASS (klass);

  gobject_class->set_property = gst_spot_src_set_property;
  gobject_class->get_property = gst_spot_src_get_property;

  gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_spot_src_finalize);

  gstbasesrc_class->start = GST_DEBUG_FUNCPTR (gst_spot_src_start);
  gstbasesrc_class->stop = GST_DEBUG_FUNCPTR (gst_spot_src_stop);
  gstbasesrc_class->unlock = GST_DEBUG_FUNCPTR (gst_spot_src_unlock);
  gstbasesrc_class->unlock_stop = GST_DEBUG_FUNCPTR (gst_spot_src_unlock_stop);
  gstbasesrc_class->is_seekable = GST_DEBUG_FUNCPTR (gst_spot_src_is_seekable);
  gstbasesrc_class->get_size = GST_DEBUG_FUNCPTR (gst_spot_src_get_size);
  gstbasesrc_class->create = GST_DEBUG_FUNCPTR (gst_spot_src_create);
  gstbasesrc_class->query = GST_DEBUG_FUNCPTR (gst_spot_src_query);

  g_object_class_install_property (gobject_class, ARG_USER,
      g_param_spec_string ("user", "Username", "Username for premium spotify account",
          DEFAULT_USER, G_PARAM_READWRITE));

  g_object_class_install_property (gobject_class, ARG_PASS,
      g_param_spec_string ("pass", "Password", "Password for premium spotify account",
	  DEFAULT_PASS, G_PARAM_READWRITE));

  g_object_class_install_property (gobject_class, ARG_URI,
      g_param_spec_string ("uri", "URI", "A URI", "unknown",
          G_PARAM_READWRITE));

  g_object_class_install_property (gobject_class, ARG_BUFFER_TIME,
      g_param_spec_uint64 ("buffer-time", "buffer time in us", "buffer time in us",
                      0,BUFFER_TIME_MAX,BUFFER_TIME_DEFAULT,
                      G_PARAM_READWRITE));

  gst_spot_signals[SIGNAL_PLAY_TOKEN_LOST] =
      g_signal_new ("play-token-lost", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_FIRST,
      0, NULL, NULL,
      g_cclosure_marshal_VOID__VOID, G_TYPE_NONE, 0);
}

static void
gst_codec_src_class_init (GstCodecSrcClass * klass)
{
  GstPushSrcClass *pushsrc_class = GST_PUSH_SRC_CLASS (klass);
  GstBaseSrcClass *basesrc_class = GST_BASE_SRC_CLASS (klass);
  static GstStaticPadTemplate src_templ = GST_STATIC_PAD_TEMPLATE ("src",
      GST_PAD_SRC, GST_PAD_ALWAYS,
      GST_STATIC_CAPS ("application/x-codec")
      );
  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);

  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&src_templ));
  gst_element_class_set_metadata (element_class,
      "Codec Src", "Source/Video", "yep", "me");

  pushsrc_class->create = gst_codec_src_create;
  basesrc_class->get_caps = gst_codec_src_get_caps;
}

static void
gst_red_video_src_class_init (GstRedVideoSrcClass * klass)
{
  GstPushSrcClass *pushsrc_class = GST_PUSH_SRC_CLASS (klass);
  GstBaseSrcClass *basesrc_class = GST_BASE_SRC_CLASS (klass);
  static GstStaticPadTemplate src_templ = GST_STATIC_PAD_TEMPLATE ("src",
      GST_PAD_SRC, GST_PAD_ALWAYS,
      GST_STATIC_CAPS ("video/x-raw, format=(string)I420")
      );
  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);

  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&src_templ));
  gst_element_class_set_metadata (element_class,
      "Red Video Src", "Source/Video", "yep", "me");

  pushsrc_class->create = gst_red_video_src_create;
  basesrc_class->get_caps = gst_red_video_src_get_caps;
}

static GstCaps *
gst_gl_test_src_fixate (GstBaseSrc * bsrc, GstCaps * caps)
{
  GstStructure *structure;

  GST_DEBUG ("fixate");

  caps = gst_caps_make_writable (caps);

  structure = gst_caps_get_structure (caps, 0);

  gst_structure_fixate_field_nearest_int (structure, "width", 320);
  gst_structure_fixate_field_nearest_int (structure, "height", 240);
  gst_structure_fixate_field_nearest_fraction (structure, "framerate", 30, 1);

  caps = GST_BASE_SRC_CLASS (parent_class)->fixate (bsrc, caps);

  return caps;
}

static void
gst_dtmf_src_class_init (GstDTMFSrcClass * klass)
{
  GObjectClass *gobject_class;
  GstBaseSrcClass *gstbasesrc_class;
  GstElementClass *gstelement_class;

  gobject_class = G_OBJECT_CLASS (klass);
  gstbasesrc_class = GST_BASE_SRC_CLASS (klass);
  gstelement_class = GST_ELEMENT_CLASS (klass);


  GST_DEBUG_CATEGORY_INIT (gst_dtmf_src_debug, "dtmfsrc", 0, "dtmfsrc element");

  gst_element_class_add_pad_template (gstelement_class,
      gst_static_pad_template_get (&gst_dtmf_src_template));

  gst_element_class_set_metadata (gstelement_class, "DTMF tone generator",
      "Source/Audio",
      "Generates DTMF tones",
      "Youness Alaoui <[email protected]>");


  gobject_class->finalize = gst_dtmf_src_finalize;
  gobject_class->set_property = gst_dtmf_src_set_property;
  gobject_class->get_property = gst_dtmf_src_get_property;

  g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_INTERVAL,
      g_param_spec_uint ("interval", "Interval between tone packets",
          "Interval in ms between two tone packets", MIN_PACKET_INTERVAL,
          MAX_PACKET_INTERVAL, DEFAULT_PACKET_INTERVAL,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  gstelement_class->change_state =
      GST_DEBUG_FUNCPTR (gst_dtmf_src_change_state);
  gstelement_class->send_event = GST_DEBUG_FUNCPTR (gst_dtmf_src_send_event);
  gstbasesrc_class->unlock = GST_DEBUG_FUNCPTR (gst_dtmf_src_unlock);
  gstbasesrc_class->unlock_stop = GST_DEBUG_FUNCPTR (gst_dtmf_src_unlock_stop);

  gstbasesrc_class->event = GST_DEBUG_FUNCPTR (gst_dtmf_src_handle_event);
  gstbasesrc_class->create = GST_DEBUG_FUNCPTR (gst_dtmf_src_create);
  gstbasesrc_class->negotiate = GST_DEBUG_FUNCPTR (gst_dtmf_src_negotiate);
}

static void
gst_avdtp_src_class_init (GstAvdtpSrcClass * klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
  GstBaseSrcClass *basesrc_class = GST_BASE_SRC_CLASS (klass);

  parent_class = g_type_class_peek_parent (klass);

  gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_avdtp_src_finalize);
  gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_avdtp_src_set_property);
  gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_avdtp_src_get_property);

  basesrc_class->start = GST_DEBUG_FUNCPTR (gst_avdtp_src_start);
  basesrc_class->stop = GST_DEBUG_FUNCPTR (gst_avdtp_src_stop);
  basesrc_class->create = GST_DEBUG_FUNCPTR (gst_avdtp_src_create);
  basesrc_class->unlock = GST_DEBUG_FUNCPTR (gst_avdtp_src_unlock);
  basesrc_class->unlock_stop = GST_DEBUG_FUNCPTR (gst_avdtp_src_unlock_stop);
  basesrc_class->get_caps = GST_DEBUG_FUNCPTR (gst_avdtp_src_getcaps);
  basesrc_class->query = GST_DEBUG_FUNCPTR (gst_avdtp_src_query);

  g_object_class_install_property (gobject_class, PROP_TRANSPORT,
      g_param_spec_string ("transport",
          "Transport", "Use configured transport", NULL, G_PARAM_READWRITE));

  g_object_class_install_property (gobject_class, PROP_TRANSPORT_VOLUME,
      g_param_spec_uint ("transport-volume",
          "Transport volume",
          "Volume of the transport (only valid if transport is acquired)",
          0, 127, 127, G_PARAM_READWRITE));

  gst_element_class_set_static_metadata (element_class,
      "Bluetooth AVDTP Source",
      "Source/Audio/Network/RTP",
      "Receives audio from an A2DP device",
      "Arun Raghavan <[email protected]>");

  GST_DEBUG_CATEGORY_INIT (avdtpsrc_debug, "avdtpsrc", 0,
      "Bluetooth AVDTP Source");

  gst_element_class_add_static_pad_template (element_class,
      &gst_avdtp_src_template);
}

static void
gst_pulsesrc_class_init (GstPulseSrcClass * klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  GstAudioSrcClass *gstaudiosrc_class = GST_AUDIO_SRC_CLASS (klass);
  GstBaseSrcClass *gstbasesrc_class = GST_BASE_SRC_CLASS (klass);
  GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);

  gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_pulsesrc_finalize);
  gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_pulsesrc_set_property);
  gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_pulsesrc_get_property);

  gstelement_class->change_state =
      GST_DEBUG_FUNCPTR (gst_pulsesrc_change_state);

  gstbasesrc_class->negotiate = GST_DEBUG_FUNCPTR (gst_pulsesrc_negotiate);

  gstaudiosrc_class->open = GST_DEBUG_FUNCPTR (gst_pulsesrc_open);
  gstaudiosrc_class->close = GST_DEBUG_FUNCPTR (gst_pulsesrc_close);
  gstaudiosrc_class->prepare = GST_DEBUG_FUNCPTR (gst_pulsesrc_prepare);
  gstaudiosrc_class->unprepare = GST_DEBUG_FUNCPTR (gst_pulsesrc_unprepare);
  gstaudiosrc_class->read = GST_DEBUG_FUNCPTR (gst_pulsesrc_read);
  gstaudiosrc_class->delay = GST_DEBUG_FUNCPTR (gst_pulsesrc_delay);
  gstaudiosrc_class->reset = GST_DEBUG_FUNCPTR (gst_pulsesrc_reset);

  /* Overwrite GObject fields */
  g_object_class_install_property (gobject_class,
      PROP_SERVER,
      g_param_spec_string ("server", "Server",
          "The PulseAudio server to connect to", DEFAULT_SERVER,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class, PROP_DEVICE,
      g_param_spec_string ("device", "Device",
          "The PulseAudio source device to connect to", DEFAULT_DEVICE,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class,
      PROP_DEVICE_NAME,
      g_param_spec_string ("device-name", "Device name",
          "Human-readable name of the sound device", DEFAULT_DEVICE_NAME,
          G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
}

static void
gst_fd_src_class_init (GstFdSrcClass * klass)
{
  GObjectClass *gobject_class;
  GstBaseSrcClass *gstbasesrc_class;
  GstPushSrcClass *gstpush_src_class;

  gobject_class = G_OBJECT_CLASS (klass);
  gstbasesrc_class = GST_BASE_SRC_CLASS (klass);
  gstpush_src_class = GST_PUSH_SRC_CLASS (klass);

  gobject_class->set_property = gst_fd_src_set_property;
  gobject_class->get_property = gst_fd_src_get_property;
  gobject_class->dispose = gst_fd_src_dispose;

  g_object_class_install_property (gobject_class, PROP_FD,
      g_param_spec_int ("fd", "fd", "An open file descriptor to read from",
          0, G_MAXINT, DEFAULT_FD, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
  /**
   * GstFdSrc:timeout
   *
   * Post a message after timeout microseconds
   *
   * Since: 0.10.21
   */
  g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_TIMEOUT,
      g_param_spec_uint64 ("timeout", "Timeout",
          "Post a message after timeout microseconds (0 = disabled)", 0,
          G_MAXUINT64, DEFAULT_TIMEOUT,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  gstbasesrc_class->start = GST_DEBUG_FUNCPTR (gst_fd_src_start);
  gstbasesrc_class->stop = GST_DEBUG_FUNCPTR (gst_fd_src_stop);
  gstbasesrc_class->unlock = GST_DEBUG_FUNCPTR (gst_fd_src_unlock);
  gstbasesrc_class->unlock_stop = GST_DEBUG_FUNCPTR (gst_fd_src_unlock_stop);
  gstbasesrc_class->is_seekable = GST_DEBUG_FUNCPTR (gst_fd_src_is_seekable);
  gstbasesrc_class->get_size = GST_DEBUG_FUNCPTR (gst_fd_src_get_size);
  gstbasesrc_class->do_seek = GST_DEBUG_FUNCPTR (gst_fd_src_do_seek);
  gstbasesrc_class->query = GST_DEBUG_FUNCPTR (gst_fd_src_query);

  gstpush_src_class->create = GST_DEBUG_FUNCPTR (gst_fd_src_create);
}

static gboolean
gst_osx_video_src_query (GstBaseSrc * bsrc, GstQuery * query)
{
  GstOSXVideoSrc *self;
  gboolean res = FALSE;

  self = GST_OSX_VIDEO_SRC (bsrc);

  switch (GST_QUERY_TYPE (query)) {
    case GST_QUERY_LATENCY:
    {
      GstClockTime min_latency, max_latency;
      gint fps_n, fps_d;

      fps_n = FRAMERATE;
      fps_d = 1;

      /* min latency is the time to capture one frame */
      min_latency = gst_util_uint64_scale_int (GST_SECOND, fps_d, fps_n);

      /* max latency is total duration of the frame buffer */
      // FIXME: we don't know what this is, so we'll just say 2 frames
      max_latency = 2 * min_latency;

      GST_DEBUG_OBJECT (bsrc,
          "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);

      res = TRUE;
      break;
    }
    default:
      res = GST_BASE_SRC_CLASS (parent_class)->query (bsrc, query);
      break;
  }

  return res;
}

static void
gst_cel_video_src_class_init (GstCelVideoSrcClass * klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
  GstBaseSrcClass *gstbasesrc_class = GST_BASE_SRC_CLASS (klass);
  GstPushSrcClass *gstpushsrc_class = GST_PUSH_SRC_CLASS (klass);

  gobject_class->dispose = gst_cel_video_src_dispose;
  gobject_class->finalize = gst_cel_video_src_finalize;
  gobject_class->get_property = gst_cel_video_src_get_property;
  gobject_class->set_property = gst_cel_video_src_set_property;

  gstelement_class->change_state = gst_cel_video_src_change_state;

  gstbasesrc_class->get_caps = gst_cel_video_src_get_caps;
  gstbasesrc_class->set_caps = gst_cel_video_src_set_caps;
  gstbasesrc_class->start = gst_cel_video_src_start;
  gstbasesrc_class->stop = gst_cel_video_src_stop;
  gstbasesrc_class->query = gst_cel_video_src_query;
  gstbasesrc_class->unlock = gst_cel_video_src_unlock;
  gstbasesrc_class->unlock_stop = gst_cel_video_src_unlock_stop;

  gstpushsrc_class->create = gst_cel_video_src_create;

  g_object_class_install_property (gobject_class, PROP_DEVICE_INDEX,
      g_param_spec_int ("device-index", "Device Index",
          "The zero-based device index",
          -1, G_MAXINT, DEFAULT_DEVICE_INDEX,
          G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS));
  g_object_class_install_property (gobject_class, PROP_DO_STATS,
      g_param_spec_boolean ("do-stats", "Enable statistics",
          "Enable logging of statistics", DEFAULT_DO_STATS,
          G_PARAM_CONSTRUCT | G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
  g_object_class_install_property (gobject_class, PROP_FPS,
      g_param_spec_int ("fps", "Frames per second",
          "Last measured framerate, if statistics are enabled",
          -1, G_MAXINT, -1, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));

  GST_DEBUG_CATEGORY_INIT (gst_cel_video_src_debug, "celvideosrc",
      0, "iOS Celestial video source");
}

static GstCaps *
gst_rpi_cam_src_fixate (GstBaseSrc * basesrc, GstCaps * caps)
{
  GstStructure *structure;
  gint i;
  GST_DEBUG_OBJECT (basesrc, "fixating caps %" GST_PTR_FORMAT, caps);
  caps = gst_caps_make_writable (caps);
  for (i = 0; i < gst_caps_get_size (caps); ++i) {
    structure = gst_caps_get_structure (caps, i);
    /* Fixate to 1920x1080 resolution if possible */
    gst_structure_fixate_field_nearest_int (structure, "width", 1920);
    gst_structure_fixate_field_nearest_int (structure, "height", 1080);
    gst_structure_fixate_field_nearest_fraction (structure, "framerate", 30, 1);
    gst_structure_fixate_field (structure, "format");
  }

  GST_DEBUG_OBJECT (basesrc, "fixated caps %" GST_PTR_FORMAT, caps);
  caps = GST_BASE_SRC_CLASS (parent_class)->fixate (basesrc, caps);
  return caps;
}