/*****************************************************************************
 * OpenDecoder: probe the decoder and return score
 *****************************************************************************/
static int OpenDecoder( vlc_object_t *p_this )
{
    decoder_t *p_dec = ( decoder_t* )p_this;
    decoder_sys_t *p_sys;
    GstStateChangeReturn i_ret;
    gboolean b_ret;
    sink_src_caps_t caps = { NULL, NULL };
    GstStructure *p_str;
    GstAppSrcCallbacks cb;
    int i_rval = VLC_SUCCESS;
    GList *p_list;
    bool dbin;

#define VLC_GST_CHECK( r, v, s, t ) \
    { if( r == v ){ msg_Err( p_dec, s ); i_rval = t; goto fail; } }

    if( !vlc_gst_init( ))
    {
        msg_Err( p_dec, "failed to register vlcvideosink" );
        return VLC_EGENERIC;
    }

    p_str = vlc_to_gst_fmt( &p_dec->fmt_in );
    if( !p_str )
        return VLC_EGENERIC;

    /* Allocate the memory needed to store the decoder's structure */
    p_sys = p_dec->p_sys = calloc( 1, sizeof( *p_sys ) );
    if( p_sys == NULL )
    {
        gst_structure_free( p_str );
        return VLC_ENOMEM;
    }

    dbin = var_CreateGetBool( p_dec, "use-decodebin" );
    msg_Dbg( p_dec, "Using decodebin? %s", dbin ? "yes ":"no" );

    caps.p_sinkcaps = gst_caps_new_empty( );
    gst_caps_append_structure( caps.p_sinkcaps, p_str );
    /* Currently supports only system memory raw output format */
    caps.p_srccaps = gst_caps_new_empty_simple( "video/x-raw" );

    /* Get the list of all the available gstreamer decoders */
    p_list = gst_element_factory_list_get_elements(
            GST_ELEMENT_FACTORY_TYPE_DECODER, GST_RANK_MARGINAL );
    VLC_GST_CHECK( p_list, NULL, "no decoder list found", VLC_ENOMOD );
    if( !dbin )
    {
        GList *p_l;
        /* Sort them as per ranks */
        p_list = g_list_sort( p_list, gst_plugin_feature_rank_compare_func );
        VLC_GST_CHECK( p_list, NULL, "failed to sort decoders list",
                VLC_ENOMOD );
        p_l = g_list_find_custom( p_list, &caps, find_decoder_func );
        VLC_GST_CHECK( p_l, NULL, "no suitable decoder found",
                VLC_ENOMOD );
        /* create the decoder with highest rank */
        p_sys->p_decode_in = gst_element_factory_create(
                ( GstElementFactory* )p_l->data, NULL );
        VLC_GST_CHECK( p_sys->p_decode_in, NULL,
                "failed to create decoder", VLC_ENOMOD );
    }
    else
    {
        GList *p_l;
        /* Just check if any suitable decoder exists, rest will be
         * handled by decodebin */
        p_l = g_list_find_custom( p_list, &caps, find_decoder_func );
        VLC_GST_CHECK( p_l, NULL, "no suitable decoder found",
                VLC_ENOMOD );
    }
    gst_plugin_feature_list_free( p_list );
    p_list = NULL;
    gst_caps_unref( caps.p_srccaps );
    caps.p_srccaps = NULL;

    p_sys->b_prerolled = false;
    p_sys->b_running = false;

    /* Queue: GStreamer thread will dump buffers into this queue,
     * DecodeBlock() will pop out the buffers from the queue */
    p_sys->p_que = gst_atomic_queue_new( 0 );
    VLC_GST_CHECK( p_sys->p_que, NULL, "failed to create queue",
            VLC_ENOMEM );

    p_sys->p_decode_src = gst_element_factory_make( "appsrc", NULL );
    VLC_GST_CHECK( p_sys->p_decode_src, NULL, "appsrc not found",
            VLC_ENOMOD );
    g_object_set( G_OBJECT( p_sys->p_decode_src ), "caps", caps.p_sinkcaps,
            "emit-signals", TRUE, "format", GST_FORMAT_BYTES,
            "stream-type", GST_APP_STREAM_TYPE_SEEKABLE,
            /* Making DecodeBlock() to block on appsrc with max queue size of 1 byte.
             * This will make the push_buffer() tightly coupled with the buffer
             * flow from appsrc -> decoder. push_buffer() will only return when
             * the same buffer it just fed to appsrc has also been fed to the
             * decoder element as well */
            "block", TRUE, "max-bytes", ( guint64 )1, NULL );
//.........这里部分代码省略.........

bool CvCapture_GStreamer::open( int type, const char* filename )
{
    close();
    CV_FUNCNAME("cvCaptureFromCAM_GStreamer");

    __BEGIN__;

    gst_initializer::init();

//    if(!isInited) {
//        printf("gst_init\n");
//        gst_init (NULL, NULL);

//        gst_debug_set_active(TRUE);
//        gst_debug_set_colored(TRUE);
//        gst_debug_set_default_threshold(GST_LEVEL_WARNING);

//        isInited = true;
//    }
    bool stream = false;
    bool manualpipeline = false;
    char *uri = NULL;
    uridecodebin = NULL;
    if(type != CV_CAP_GSTREAMER_FILE) {
        close();
        return false;
    }

    if(!gst_uri_is_valid(filename)) {
        uri = realpath(filename, NULL);
        stream=false;
        if(uri) {
            uri = g_filename_to_uri(uri, NULL, NULL);
            if(!uri) {
                CV_WARN("GStreamer: Error opening file\n");
                close();
                return false;
            }
        } else {
            GError *err = NULL;
            //uridecodebin = gst_parse_bin_from_description(filename, FALSE, &err);
            uridecodebin = gst_parse_launch(filename, &err);
            if(!uridecodebin) {
                CV_WARN("GStreamer: Error opening bin\n");
                close();
                return false;
            }
            stream = true;
            manualpipeline = true;
        }
    } else {
        stream = true;
        uri = g_strdup(filename);
    }

    if(!uridecodebin) {
        uridecodebin = gst_element_factory_make ("uridecodebin", NULL);
        g_object_set(G_OBJECT(uridecodebin),"uri",uri, NULL);
        if(!uridecodebin) {
            CV_WARN("GStreamer: Failed to create uridecodebin\n");
            close();
            return false;
        }
    }

    if(manualpipeline) {
        GstIterator *it = gst_bin_iterate_sinks(GST_BIN(uridecodebin));
        if(gst_iterator_next(it, (gpointer *)&sink) != GST_ITERATOR_OK) {
        CV_ERROR(CV_StsError, "GStreamer: cannot find appsink in manual pipeline\n");
        return false;
        }

    pipeline = uridecodebin;
    } else {
    pipeline = gst_pipeline_new (NULL);

        color = gst_element_factory_make("ffmpegcolorspace", NULL);
        sink = gst_element_factory_make("appsink", NULL);

        gst_bin_add_many(GST_BIN(pipeline), uridecodebin, color, sink, NULL);
        g_signal_connect(uridecodebin, "pad-added", G_CALLBACK(newPad), color);

        if(!gst_element_link(color, sink)) {
            CV_ERROR(CV_StsError, "GStreamer: cannot link color -> sink\n");
            gst_object_unref(pipeline);
            return false;
        }
    }

    gst_app_sink_set_max_buffers (GST_APP_SINK(sink), 1);
    gst_app_sink_set_drop (GST_APP_SINK(sink), stream);
    caps = gst_caps_new_simple("video/x-raw-rgb",
                               "red_mask",   G_TYPE_INT, 0x0000FF,
                               "green_mask", G_TYPE_INT, 0x00FF00,
                               "blue_mask",  G_TYPE_INT, 0xFF0000,
                               NULL);
    gst_app_sink_set_caps(GST_APP_SINK(sink), caps);
    gst_caps_unref(caps);

    if(gst_element_set_state(GST_ELEMENT(pipeline), GST_STATE_READY) ==
//.........这里部分代码省略.........

bool CvCapture_GStreamer::setProperty( int propId, double value )
{
       GstFormat format;
    GstSeekFlags flags;

    if(!pipeline) {
        CV_WARN("GStreamer: no pipeline");
        return false;
    }

    switch(propId) {
    case CV_CAP_PROP_POS_MSEC:
        format = GST_FORMAT_TIME;
        flags = (GstSeekFlags) (GST_SEEK_FLAG_FLUSH|GST_SEEK_FLAG_ACCURATE);
        if(!gst_element_seek_simple(GST_ELEMENT(pipeline), format,
                        flags, (gint64) (value * GST_MSECOND))) {
            CV_WARN("GStreamer: unable to seek");
        }
        break;
    case CV_CAP_PROP_POS_FRAMES:
        format = GST_FORMAT_DEFAULT;
        flags = (GstSeekFlags) (GST_SEEK_FLAG_FLUSH|GST_SEEK_FLAG_ACCURATE);
        if(!gst_element_seek_simple(GST_ELEMENT(pipeline), format,
                        flags, (gint64) value)) {
            CV_WARN("GStreamer: unable to seek");
        }
        break;
    case CV_CAP_PROP_POS_AVI_RATIO:
        format = GST_FORMAT_PERCENT;
        flags = (GstSeekFlags) (GST_SEEK_FLAG_FLUSH|GST_SEEK_FLAG_ACCURATE);
        if(!gst_element_seek_simple(GST_ELEMENT(pipeline), format,
                        flags, (gint64) (value * GST_FORMAT_PERCENT_MAX))) {
            CV_WARN("GStreamer: unable to seek");
        }
        break;
    case CV_CAP_PROP_FRAME_WIDTH:
        if(value > 0)
            setFilter("width", G_TYPE_INT, (int) value, 0);
        else
            removeFilter("width");
        break;
    case CV_CAP_PROP_FRAME_HEIGHT:
        if(value > 0)
            setFilter("height", G_TYPE_INT, (int) value, 0);
        else
            removeFilter("height");
        break;
    case CV_CAP_PROP_FPS:
        if(value > 0) {
            int num, denom;
            num = (int) value;
            if(value != num) { // FIXME this supports only fractions x/1 and x/2
                num = (int) (value * 2);
                denom = 2;
            } else
                denom = 1;

            setFilter("framerate", GST_TYPE_FRACTION, num, denom);
        } else
            removeFilter("framerate");
        break;
    case CV_CAP_PROP_FOURCC:
    case CV_CAP_PROP_FRAME_COUNT:
    case CV_CAP_PROP_FORMAT:
    case CV_CAP_PROP_MODE:
    case CV_CAP_PROP_BRIGHTNESS:
    case CV_CAP_PROP_CONTRAST:
    case CV_CAP_PROP_SATURATION:
    case CV_CAP_PROP_HUE:
    case CV_CAP_PROP_GAIN:
    case CV_CAP_PROP_CONVERT_RGB:
        break;
    case CV_CAP_GSTREAMER_QUEUE_LENGTH:
        if(!sink)
            break;
        gst_app_sink_set_max_buffers(GST_APP_SINK(sink), (guint) value);
        break;
    default:
        CV_WARN("GStreamer: unhandled property");
    }
    return false;
}

/* Return the possible output caps based on inputs and downstream prefs */
static GstCaps *
_update_caps (GstVideoAggregator * vagg, GstCaps * caps, GstCaps * filter)
{
  GstGLStereoMix *mix = GST_GL_STEREO_MIX (vagg);
  GList *l;
  gint best_width = -1, best_height = -1;
  gdouble best_fps = -1, cur_fps;
  gint best_fps_n = 0, best_fps_d = 1;
  GstVideoInfo *mix_info;
  GstCaps *blend_caps, *tmp_caps;
  GstCaps *out_caps;

  GST_OBJECT_LOCK (vagg);

  for (l = GST_ELEMENT (vagg)->sinkpads; l; l = l->next) {
    GstVideoAggregatorPad *pad = l->data;
    GstVideoInfo tmp = pad->info;
    gint this_width, this_height;
    gint fps_n, fps_d;

    if (!pad->info.finfo)
      continue;

    /* This can happen if we release a pad and another pad hasn't been negotiated_caps yet */
    if (GST_VIDEO_INFO_FORMAT (&pad->info) == GST_VIDEO_FORMAT_UNKNOWN)
      continue;

    /* Convert to per-view width/height for unpacked forms */
    gst_video_multiview_video_info_change_mode (&tmp,
        GST_VIDEO_MULTIVIEW_MODE_SEPARATED, GST_VIDEO_MULTIVIEW_FLAGS_NONE);

    this_width = GST_VIDEO_INFO_WIDTH (&tmp);
    this_height = GST_VIDEO_INFO_HEIGHT (&tmp);
    fps_n = GST_VIDEO_INFO_FPS_N (&tmp);
    fps_d = GST_VIDEO_INFO_FPS_D (&tmp);

    GST_INFO_OBJECT (vagg, "Input pad %" GST_PTR_FORMAT
        " w %u h %u", pad, this_width, this_height);

    if (this_width == 0 || this_height == 0)
      continue;

    if (best_width < this_width)
      best_width = this_width;
    if (best_height < this_height)
      best_height = this_height;

    if (fps_d == 0)
      cur_fps = 0.0;
    else
      gst_util_fraction_to_double (fps_n, fps_d, &cur_fps);

    if (best_fps < cur_fps) {
      best_fps = cur_fps;
      best_fps_n = fps_n;
      best_fps_d = fps_d;
    }

    /* FIXME: Preserve PAR for at least one input when different sized inputs */
  }
  GST_OBJECT_UNLOCK (vagg);

  mix_info = &mix->mix_info;
  gst_video_info_set_format (mix_info, GST_VIDEO_FORMAT_RGBA, best_width,
      best_height);

  GST_VIDEO_INFO_FPS_N (mix_info) = best_fps_n;
  GST_VIDEO_INFO_FPS_D (mix_info) = best_fps_d;

  GST_VIDEO_INFO_MULTIVIEW_MODE (mix_info) = GST_VIDEO_MULTIVIEW_MODE_SEPARATED;
  GST_VIDEO_INFO_VIEWS (mix_info) = 2;

  /* FIXME: If input is marked as flipped or flopped, preserve those flags */
  GST_VIDEO_INFO_MULTIVIEW_FLAGS (mix_info) = GST_VIDEO_MULTIVIEW_FLAGS_NONE;

  /* Choose our output format based on downstream preferences */
  blend_caps = gst_video_info_to_caps (mix_info);

  gst_caps_set_features (blend_caps, 0,
      gst_caps_features_from_string (GST_CAPS_FEATURE_MEMORY_GL_MEMORY));

  tmp_caps = get_converted_caps (GST_GL_STEREO_MIX (vagg), blend_caps);
  gst_caps_unref (blend_caps);

  out_caps = gst_caps_intersect (caps, tmp_caps);
  gst_caps_unref (tmp_caps);

  GST_DEBUG_OBJECT (vagg, "Possible output caps %" GST_PTR_FORMAT, out_caps);

  return out_caps;
}

static GstFlowReturn
gst_opus_dec_parse_header (GstOpusDec * dec, GstBuffer * buf)
{
  const guint8 *data;
  GstAudioChannelPosition pos[64];
  const GstAudioChannelPosition *posn = NULL;
  GstMapInfo map;

  if (!gst_opus_header_is_id_header (buf)) {
    GST_ERROR_OBJECT (dec, "Header is not an Opus ID header");
    return GST_FLOW_ERROR;
  }

  gst_buffer_map (buf, &map, GST_MAP_READ);
  data = map.data;

  if (!(dec->n_channels == 0 || dec->n_channels == data[9])) {
    gst_buffer_unmap (buf, &map);
    GST_ERROR_OBJECT (dec, "Opus ID header has invalid channels");
    return GST_FLOW_ERROR;
  }

  dec->n_channels = data[9];
  dec->sample_rate = GST_READ_UINT32_LE (data + 12);
  dec->pre_skip = GST_READ_UINT16_LE (data + 10);
  dec->r128_gain = GST_READ_UINT16_LE (data + 16);
  dec->r128_gain_volume = gst_opus_dec_get_r128_volume (dec->r128_gain);
  GST_INFO_OBJECT (dec,
      "Found pre-skip of %u samples, R128 gain %d (volume %f)",
      dec->pre_skip, dec->r128_gain, dec->r128_gain_volume);

  dec->channel_mapping_family = data[18];
  if (dec->channel_mapping_family == 0) {
    /* implicit mapping */
    GST_INFO_OBJECT (dec, "Channel mapping family 0, implicit mapping");
    dec->n_streams = dec->n_stereo_streams = 1;
    dec->channel_mapping[0] = 0;
    dec->channel_mapping[1] = 1;
  } else {
    dec->n_streams = data[19];
    dec->n_stereo_streams = data[20];
    memcpy (dec->channel_mapping, data + 21, dec->n_channels);

    if (dec->channel_mapping_family == 1) {
      GST_INFO_OBJECT (dec, "Channel mapping family 1, Vorbis mapping");
      switch (dec->n_channels) {
        case 1:
        case 2:
          /* nothing */
          break;
        case 3:
        case 4:
        case 5:
        case 6:
        case 7:
        case 8:
          posn = gst_opus_channel_positions[dec->n_channels - 1];
          break;
        default:{
          gint i;

          GST_ELEMENT_WARNING (GST_ELEMENT (dec), STREAM, DECODE,
              (NULL), ("Using NONE channel layout for more than 8 channels"));

          for (i = 0; i < dec->n_channels; i++)
            pos[i] = GST_AUDIO_CHANNEL_POSITION_NONE;

          posn = pos;
        }
      }
    } else {
      GST_INFO_OBJECT (dec, "Channel mapping family %d",
          dec->channel_mapping_family);
    }
  }

  gst_opus_dec_negotiate (dec, posn);

  gst_buffer_unmap (buf, &map);

  return GST_FLOW_OK;
}

GstElement* webkitVideoSinkNew(WebCore::GStreamerGWorld* gstGWorld)
{
    GstElement* element = GST_ELEMENT(g_object_new(WEBKIT_TYPE_VIDEO_SINK, 0));
    WEBKIT_VIDEO_SINK(element)->priv->gstGWorld = gstGWorld;
    return element;
}

static void
gst_curl_smtp_sink_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstCurlSmtpSink *sink;
  GstState cur_state;

  g_return_if_fail (GST_IS_CURL_SMTP_SINK (object));
  sink = GST_CURL_SMTP_SINK (object);

  gst_element_get_state (GST_ELEMENT (sink), &cur_state, NULL, 0);
  if (cur_state != GST_STATE_PLAYING && cur_state != GST_STATE_PAUSED) {
    GST_OBJECT_LOCK (sink);

    switch (prop_id) {
      case PROP_MAIL_RCPT:
        g_free (sink->mail_rcpt);
        sink->mail_rcpt = g_value_dup_string (value);
        GST_DEBUG_OBJECT (sink, "mail-rcpt set to %s", sink->mail_rcpt);
        break;
      case PROP_MAIL_FROM:
        g_free (sink->mail_from);
        sink->mail_from = g_value_dup_string (value);
        GST_DEBUG_OBJECT (sink, "mail-from set to %s", sink->mail_from);
        break;
      case PROP_SUBJECT:
        g_free (sink->subject);
        sink->subject = g_value_dup_string (value);
        GST_DEBUG_OBJECT (sink, "subject set to %s", sink->subject);
        break;
      case PROP_MESSAGE_BODY:
        g_free (sink->message_body);
        sink->message_body = g_value_dup_string (value);
        GST_DEBUG_OBJECT (sink, "message-body set to %s", sink->message_body);
        break;
      case PROP_CONTENT_TYPE:
        g_free (sink->content_type);
        sink->content_type = g_value_dup_string (value);
        GST_DEBUG_OBJECT (sink, "content-type set to %s", sink->content_type);
        break;
      case PROP_USE_SSL:
        sink->use_ssl = g_value_get_boolean (value);
        GST_DEBUG_OBJECT (sink, "use-ssl set to %d", sink->use_ssl);
        break;
      case PROP_NBR_ATTACHMENTS:
        sink->nbr_attachments = g_value_get_int (value);
        sink->nbr_attachments_left = sink->nbr_attachments;
        GST_DEBUG_OBJECT (sink, "nbr-attachments set to %d",
            sink->nbr_attachments);
        break;
      case PROP_POP_USER_NAME:
        g_free (sink->pop_user);
        sink->pop_user = g_value_dup_string (value);
        GST_DEBUG_OBJECT (sink, "pop-user set to %s", sink->pop_user);
        break;
      case PROP_POP_USER_PASSWD:
        g_free (sink->pop_passwd);
        sink->pop_passwd = g_value_dup_string (value);
        GST_DEBUG_OBJECT (sink, "pop-passwd set to %s", sink->pop_passwd);
        break;
      case PROP_POP_LOCATION:
        g_free (sink->pop_location);
        sink->pop_location = g_value_dup_string (value);
        GST_DEBUG_OBJECT (sink, "pop-location set to %s", sink->pop_location);
        break;

      default:
        GST_DEBUG_OBJECT (sink, "invalid property id %d", prop_id);
        break;
    }

    GST_OBJECT_UNLOCK (sink);

    return;
  }

  /* in PLAYING or PAUSED state */
  GST_OBJECT_LOCK (sink);

  switch (prop_id) {
    case PROP_CONTENT_TYPE:
      g_free (sink->content_type);
      sink->content_type = g_value_dup_string (value);
      GST_DEBUG_OBJECT (sink, "content type set to %s", sink->content_type);
      break;
    default:
      GST_WARNING_OBJECT (sink, "cannot set property when PLAYING");
      break;
  }

  GST_OBJECT_UNLOCK (sink);
}

static void
gst_curl_http_sink_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstCurlHttpSink *sink;
  GstState cur_state;

  g_return_if_fail (GST_IS_CURL_HTTP_SINK (object));
  sink = GST_CURL_HTTP_SINK (object);

  gst_element_get_state (GST_ELEMENT (sink), &cur_state, NULL, 0);
  if (cur_state != GST_STATE_PLAYING && cur_state != GST_STATE_PAUSED) {
    GST_OBJECT_LOCK (sink);

    switch (prop_id) {
      case PROP_PROXY:
        g_free (sink->proxy);
        sink->proxy = g_value_dup_string (value);
        GST_DEBUG_OBJECT (sink, "proxy set to %s", sink->proxy);
        break;
      case PROP_PROXY_PORT:
        sink->proxy_port = g_value_get_int (value);
        GST_DEBUG_OBJECT (sink, "proxy port set to %d", sink->proxy_port);
        break;
      case PROP_PROXY_USER_NAME:
        g_free (sink->proxy_user);
        sink->proxy_user = g_value_dup_string (value);
        GST_DEBUG_OBJECT (sink, "proxy user set to %s", sink->proxy_user);
        break;
      case PROP_PROXY_USER_PASSWD:
        g_free (sink->proxy_passwd);
        sink->proxy_passwd = g_value_dup_string (value);
        GST_DEBUG_OBJECT (sink, "proxy password set to %s", sink->proxy_passwd);
        break;
      case PROP_USE_CONTENT_LENGTH:
        sink->use_content_length = g_value_get_boolean (value);
        GST_DEBUG_OBJECT (sink, "use_content_length set to %d",
            sink->use_content_length);
        break;
      case PROP_CONTENT_TYPE:
        g_free (sink->content_type);
        sink->content_type = g_value_dup_string (value);
        GST_DEBUG_OBJECT (sink, "content type set to %s", sink->content_type);
        break;
      default:
        GST_DEBUG_OBJECT (sink, "invalid property id %d", prop_id);
        break;
    }

    GST_OBJECT_UNLOCK (sink);

    return;
  }

  /* in PLAYING or PAUSED state */
  GST_OBJECT_LOCK (sink);

  switch (prop_id) {
    case PROP_CONTENT_TYPE:
      g_free (sink->content_type);
      sink->content_type = g_value_dup_string (value);
      GST_DEBUG_OBJECT (sink, "content type set to %s", sink->content_type);
      break;
    default:
      GST_WARNING_OBJECT (sink, "cannot set property when PLAYING");
      break;
  }

  GST_OBJECT_UNLOCK (sink);
}

static GstFlowReturn
gst_opus_dec_parse_header (GstOpusDec * dec, GstBuffer * buf)
{
  const guint8 *data = GST_BUFFER_DATA (buf);
  GstCaps *caps;
  const GstAudioChannelPosition *pos = NULL;

  if (!gst_opus_header_is_id_header (buf)) {
    GST_ERROR_OBJECT (dec, "Header is not an Opus ID header");
    return GST_FLOW_ERROR;
  }
  if (!(dec->n_channels == 0 || dec->n_channels == data[9])) {
    GST_ERROR_OBJECT (dec, "Opus ID header has invalid channels");
    return GST_FLOW_ERROR;
  }

  dec->n_channels = data[9];
  dec->pre_skip = GST_READ_UINT16_LE (data + 10);
  dec->r128_gain = GST_READ_UINT16_LE (data + 16);
  dec->r128_gain_volume = gst_opus_dec_get_r128_volume (dec->r128_gain);
  GST_INFO_OBJECT (dec,
      "Found pre-skip of %u samples, R128 gain %d (volume %f)",
      dec->pre_skip, dec->r128_gain, dec->r128_gain_volume);

  dec->channel_mapping_family = data[18];
  if (dec->channel_mapping_family == 0) {
    /* implicit mapping */
    GST_INFO_OBJECT (dec, "Channel mapping family 0, implicit mapping");
    dec->n_streams = dec->n_stereo_streams = 1;
    dec->channel_mapping[0] = 0;
    dec->channel_mapping[1] = 1;
  } else {
    dec->n_streams = data[19];
    dec->n_stereo_streams = data[20];
    memcpy (dec->channel_mapping, data + 21, dec->n_channels);

    if (dec->channel_mapping_family == 1) {
      GST_INFO_OBJECT (dec, "Channel mapping family 1, Vorbis mapping");
      switch (dec->n_channels) {
        case 1:
        case 2:
          /* nothing */
          break;
        case 3:
        case 4:
        case 5:
        case 6:
        case 7:
        case 8:
          pos = gst_opus_channel_positions[dec->n_channels - 1];
          break;
        default:{
          gint i;
          GstAudioChannelPosition *posn =
              g_new (GstAudioChannelPosition, dec->n_channels);

          GST_ELEMENT_WARNING (GST_ELEMENT (dec), STREAM, DECODE,
              (NULL), ("Using NONE channel layout for more than 8 channels"));

          for (i = 0; i < dec->n_channels; i++)
            posn[i] = GST_AUDIO_CHANNEL_POSITION_NONE;

          pos = posn;
        }
      }
    } else {
      GST_INFO_OBJECT (dec, "Channel mapping family %d",
          dec->channel_mapping_family);
    }
  }

  caps = gst_opus_dec_negotiate (dec);

  if (pos) {
    GST_DEBUG_OBJECT (dec, "Setting channel positions on caps");
    gst_audio_set_channel_positions (gst_caps_get_structure (caps, 0), pos);
  }

  if (dec->n_channels > 8) {
    g_free ((GstAudioChannelPosition *) pos);
  }

  GST_INFO_OBJECT (dec, "Setting src caps to %" GST_PTR_FORMAT, caps);
  gst_pad_set_caps (GST_AUDIO_DECODER_SRC_PAD (dec), caps);
  gst_caps_unref (caps);

  return GST_FLOW_OK;
}

int GStreamer_init(const char *mplayer)
{
	GError* error;
	GstBus *bus;
	GstElement *videosink, *audiosink;
	int err;

	if (g_initialized)
		g_error("GStreamer: already initialized, call destroy first!\n");

	g_state_callback = NULL;
	g_duration = 0;
	g_position = 0;

	/* pthread synchronization */
	pthread_mutex_init(&g_mutex, NULL);
	err = pthread_cond_init(&g_main_cond, NULL);
	if (err) {
		g_error("GStreamer: failed to initialize main condition %s\n",
				strerror(errno));
		return -1;
	}

	/* init gstreamer library */
	if (!gst_init_check(NULL, NULL, &error)) {
		g_error("GStreamer: failed to initialize gstreamer library: [%d] %s\n",
				error->code, error->message);
		g_error_free(error);
		return -1;
	}

	/* create pipeline */
	g_pipeline = gst_pipeline_new("pipeline");
	g_pipeline_name = gst_element_get_name(GST_ELEMENT(g_pipeline));

	/* register callback */
	bus = gst_pipeline_get_bus(GST_PIPELINE(g_pipeline));
	gst_bus_add_watch(bus, my_bus_callback, NULL);
	gst_object_unref(bus);

#if 0
	/* TODO unlinked when removed from pipeline */

	/* hardcode audio/video sink */
	g_videosink = create_video_sink();
	g_audiosink = create_audio_sink();

	if (!g_videosink || !g_audiosink) {
		/* TODO memory leak */
		g_error("GStreamer: failed to create sink elements\n");
		return -1;
	}
#endif

	/* prepare http/file src */
	g_filesrc = gst_element_factory_make ("filesrc", "filesrc");
	g_httpsrc = gst_element_factory_make ("souphttpsrc", "httpsrc");

	if (!g_filesrc || !g_httpsrc) {
		/* TODO memory leak */
		g_error("GStreamer: failed to create src elements %x %x\n", g_filesrc, g_httpsrc);
		return -1;
	}

	g_object_ref(g_filesrc);
	g_object_ref(g_httpsrc);

	/* initialize pipeline */
	/* TODO do for audio/video pipe separately */

	if (gst_element_set_state(g_pipeline, GST_STATE_READY) ==
		GST_STATE_CHANGE_FAILURE) {
	  g_error("GStreamer: could not set pipeline to ready\n");
	}

	/* start main loop */
	g_main_loop = g_main_loop_new(NULL, FALSE);

	err = pthread_create(&g_reader_thread, NULL, main_thread_proc, NULL);
	if (err) {
		g_error("GStreamer: failed to launch gstreamer main thread %s\n",
				strerror(errno));
		goto err_pthread;
	}

	g_print("GStreamer: SUCCESSFULLY INITIALIZED\n");
	g_initialized = 1;

	return 0;

err_pthread:
	pthread_cond_destroy(&g_main_cond);
	pthread_mutex_destroy(&g_mutex);
	
	return err;
}

static GstElement *
gst_auto_video_sink_find_best (GstAutoVideoSink * sink)
{
  GList *list, *item;
  GstElement *choice = NULL;
  GstMessage *message = NULL;
  GSList *errors = NULL;
  GstBus *bus = gst_bus_new ();
  GstPad *el_pad = NULL;
  GstCaps *el_caps = NULL;
  gboolean no_match = TRUE;

  list = gst_registry_feature_filter (gst_registry_get (),
      (GstPluginFeatureFilter) gst_auto_video_sink_factory_filter, FALSE, sink);
  list = g_list_sort (list, (GCompareFunc) gst_auto_video_sink_compare_ranks);

  GST_LOG_OBJECT (sink, "Trying to find usable video devices ...");

  for (item = list; item != NULL; item = item->next) {
    GstElementFactory *f = GST_ELEMENT_FACTORY (item->data);
    GstElement *el;

    if ((el = gst_auto_video_sink_create_element_with_pretty_name (sink, f))) {
      GstStateChangeReturn ret;

      GST_DEBUG_OBJECT (sink, "Testing %s", GST_OBJECT_NAME (f));

      /* If autovideosink has been provided with filter caps,
       * accept only sinks that match with the filter caps */
      if (sink->filter_caps) {
        el_pad = gst_element_get_static_pad (GST_ELEMENT (el), "sink");
        el_caps = gst_pad_query_caps (el_pad, NULL);
        gst_object_unref (el_pad);
        GST_DEBUG_OBJECT (sink,
            "Checking caps: %" GST_PTR_FORMAT " vs. %" GST_PTR_FORMAT,
            sink->filter_caps, el_caps);
        no_match = !gst_caps_can_intersect (sink->filter_caps, el_caps);
        gst_caps_unref (el_caps);

        if (no_match) {
          GST_DEBUG_OBJECT (sink, "Incompatible caps");
          gst_object_unref (el);
          continue;
        } else {
          GST_DEBUG_OBJECT (sink, "Found compatible caps");
        }
      }

      gst_element_set_bus (el, bus);
      ret = gst_element_set_state (el, GST_STATE_READY);
      if (ret == GST_STATE_CHANGE_SUCCESS) {
        GST_DEBUG_OBJECT (sink, "This worked!");
        choice = el;
        break;
      }

      /* collect all error messages */
      while ((message = gst_bus_pop_filtered (bus, GST_MESSAGE_ERROR))) {
        GST_DEBUG_OBJECT (sink, "error message %" GST_PTR_FORMAT, message);
        errors = g_slist_append (errors, message);
      }

      gst_element_set_state (el, GST_STATE_NULL);
      gst_object_unref (el);
    }
  }

  GST_DEBUG_OBJECT (sink, "done trying");
  if (!choice) {
    if (errors) {
      /* FIXME: we forward the first error for now; but later on it might make
       * sense to actually analyse them */
      gst_message_ref (GST_MESSAGE (errors->data));
      GST_DEBUG_OBJECT (sink, "reposting message %p", errors->data);
      gst_element_post_message (GST_ELEMENT (sink), GST_MESSAGE (errors->data));
    } else {
      /* send warning message to application and use a fakesink */
      GST_ELEMENT_WARNING (sink, RESOURCE, NOT_FOUND, (NULL),
          ("Failed to find a usable video sink"));
      choice = gst_element_factory_make ("fakesink", "fake-video-sink");
      if (g_object_class_find_property (G_OBJECT_GET_CLASS (choice), "sync"))
        g_object_set (choice, "sync", TRUE, NULL);
      gst_element_set_state (choice, GST_STATE_READY);
    }
  }
  gst_object_unref (bus);
  gst_plugin_feature_list_free (list);
  g_slist_foreach (errors, (GFunc) gst_mini_object_unref, NULL);
  g_slist_free (errors);

  return choice;
}

GstElement *create_video_sink()
{
	GstElement *bin, *decoder = NULL;
	GstIterator *iter;
	GstIteratorResult res;
	GError *error = NULL;
	GstPad *pad;
	gpointer element = NULL;
	const char* decoder_name;

#ifndef DESKTOP 
	/* create pipeline */                                                                                 
	decoder_name = "tividdec20";
	bin = gst_parse_launch_full("TIViddec2 genTimeStamps=FALSE \
			    engineName=decode \
			    codecName=h264dec numFrames=-1 \
			! videoscale method=0 \
			! video/x-raw-yuv, format=(fourcc)I420, width=320, height=240 \
			! ffmpegcolorspace \
			! video/x-raw-rgb, bpp=16 \
			! TIDmaiVideoSink displayStd=fbdev displayDevice=/dev/fb0 videoStd=QVGA \
			    videoOutput=LCD resizer=FALSE accelFrameCopy=TRUE",
			NULL, 0, &error);                                      
#else
	decoder_name = "decodebin";
	bin = gst_parse_launch_full("decodebin \
			! videoscale method=0 \
			! video/x-raw-yuv, format=(fourcc)I420, width=320, height=240 \
			! xvimagesink",
			NULL, 0, &error);                                      
#endif

	if (!bin) {
		g_error("GStreamer: failed to parse video sink pipeline\n");
		return NULL;
	}              

	gst_object_set_name(GST_OBJECT(bin), "video-sink");

	iter = gst_bin_iterate_elements(GST_BIN(bin));
	res = gst_iterator_next (iter, &element);
	while (res == GST_ITERATOR_OK) {
		gchar *name;

		name = gst_object_get_name(GST_OBJECT (element));
		if (name) {
			if (!strncmp(name, decoder_name, strlen(decoder_name))) {
				decoder = GST_ELEMENT(element); 
			}
			g_printf("GS: video sink element: %s \n", name);
			g_free (name);
		}

		gst_object_unref (element);
		element = NULL;

		res = gst_iterator_next (iter, &element);
	}
	gst_iterator_free (iter);

	if (!decoder) {
		/* mem leak */
		g_printf("decoder element not found\n");
		return NULL;
	}

	/* add ghostpad */
	pad = gst_element_get_static_pad (decoder, "sink");
	gst_element_add_pad(bin, gst_ghost_pad_new("sink", pad));
	gst_object_unref(GST_OBJECT(pad));

	return bin;
}

/* http://<xxx>/manual/html/section-bus-message-types.html */
static gboolean my_bus_callback(GstBus *bus, GstMessage *msg,
	gpointer user_data)
{
	GstMessageType msgType;
	GstObject *msgSrc;
	gchar *msgSrcName;

	/* used in switch */
	/* error message */
	gchar *debug;
	GError *err;
	GstState oldstate, newstate, pending;

	/* stream status */
	GstElement *owner;

	msgType = GST_MESSAGE_TYPE(msg);
	msgSrc = GST_MESSAGE_SRC(msg);
	msgSrcName = GST_OBJECT_NAME(msgSrc);

	switch (GST_MESSAGE_TYPE(msg)) {
	case GST_MESSAGE_EOS:
		g_print("GStreamer: end-of-stream\n");
		pthread_mutex_lock(&g_mutex);

		gst_element_set_state(GST_ELEMENT(g_pipeline), GST_STATE_NULL);
		trigger_callback(GST_STATE_NULL);

		pthread_mutex_unlock(&g_mutex);
		break;

	case GST_MESSAGE_ERROR:
		gst_message_parse_error(msg, &err, &debug);
		g_free (debug);

		g_error("GStreamer: error: [%d] %s\n", err->code, err->message);
		g_error_free(err);

		/* TODO no sleep in callback */
		pthread_mutex_lock(&g_mutex);

		/* setting state to null flushes pipeline */
		gst_element_set_state(GST_ELEMENT(g_pipeline), GST_STATE_NULL);
		trigger_callback(GST_STATE_NULL);

		pthread_mutex_unlock(&g_mutex);
		break;

	case GST_MESSAGE_STATE_CHANGED:
		gst_message_parse_state_changed(msg, &oldstate, &newstate, &pending);
#if 0   /* noisy */
		g_print("GStreamer: %s: State change: OLD: '%s', NEW: '%s', PENDING: '%s'\n",
				msgSrcName,
				gststate_get_name(oldstate),
				gststate_get_name(newstate),
				gststate_get_name(pending));
#endif
		if (!strcmp(msgSrcName, g_pipeline_name))
			trigger_callback(newstate); /* TODO GstState != GStreamer_state */

		break;

	case GST_MESSAGE_WARNING:
	case GST_MESSAGE_INFO:
		/* TODO */
		break;
	case GST_MESSAGE_APPLICATION:  /* marshal information into the main thread */
	case GST_MESSAGE_ASYNC_START:
	case GST_MESSAGE_ASYNC_DONE:
	case GST_MESSAGE_BUFFERING: /* caching of network streams */
	case GST_MESSAGE_CLOCK_LOST:
	case GST_MESSAGE_CLOCK_PROVIDE:
	case GST_MESSAGE_ELEMENT:  /* custom message, e.g. qtdemux redirect */
	case GST_MESSAGE_LATENCY:
	case GST_MESSAGE_NEW_CLOCK:
	case GST_MESSAGE_REQUEST_STATE:
	case GST_MESSAGE_SEGMENT_DONE:
	case GST_MESSAGE_SEGMENT_START:
	case GST_MESSAGE_STATE_DIRTY:
	case GST_MESSAGE_STEP_DONE:
	case GST_MESSAGE_STRUCTURE_CHANGE:
	case GST_MESSAGE_TAG: /* meta data: artist, title */
		/* ignore */
		break;
	case GST_MESSAGE_DURATION:
	default:
		g_print("GStreamer: BUS_CALL %s %d\n",
				gst_message_type_get_name(GST_MESSAGE_TYPE(msg)),
				GST_MESSAGE_TYPE(msg));
		break;
	}

	return 1;
}

//.........这里部分代码省略.........
        strncpy (input, optarg, sizeof (input) / sizeof (input[0]));
        break;

      case 'f':
        frequency = atol (optarg);
        break;

      case 'h':
        printf ("Usage: v4l2src-test [OPTION]...\n");
        for (c = 0; long_options[c].name; ++c) {
          printf ("-%c, --%s\r\t\t\t\t%s\n", long_options[c].val,
              long_options[c].name, long_options_desc[c]);
        }
        exit (0);
        break;

      case '?':
        /* getopt_long already printed an error message. */
        printf ("Use -h to see help message.\n");
        break;

      default:
        abort ();
    }
  }

  /* Print any remaining command line arguments (not options). */
  if (optind < argc) {
    printf ("Use -h to see help message.\n" "non-option ARGV-elements: ");
    while (optind < argc)
      printf ("%s ", argv[optind++]);
    putchar ('\n');
  }

  /* init */
  gst_init (&argc, &argv);

  /* create elements */
  if (!(pipeline = gst_pipeline_new ("my_pipeline"))) {
    fprintf (stderr, "error: gst_pipeline_new return NULL");
    return -1;
  }

  if (!(source = gst_element_factory_make ("v4l2src", NULL))) {
    fprintf (stderr,
        "error: gst_element_factory_make (\"v4l2src\", NULL) return NULL");
    return -1;
  }

  if (!(sink = gst_element_factory_make ("xvimagesink", NULL))) {
    fprintf (stderr,
        "error: gst_element_factory_make (\"xvimagesink\", NULL) return NULL");
    return -1;
  }

  if (numbuffers > -1) {
    g_object_set (source, "num-buffers", numbuffers, NULL);
  }
  if (device[0]) {
    g_object_set (source, "device", device, NULL);
  }
  if (input[0]) {
    g_object_set (source, "input", input, NULL);
  }
  if (frequency) {
    g_object_set (source, "frequency", frequency, NULL);
  }

  /* you would normally check that the elements were created properly */
  bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline));
  gst_bus_add_watch (bus, my_bus_callback, NULL);

  /* put together a pipeline */
  gst_bin_add_many (GST_BIN (pipeline), source, sink, NULL);
  gst_element_link_pads (source, "src", sink, "sink");

  /* start the pipeline */
  gst_element_set_state (GST_ELEMENT (pipeline), GST_STATE_PLAYING);
  loop = g_main_loop_new (NULL, FALSE);

  input_thread = g_thread_try_new ("v4l2src-test", read_user, source, NULL);

  if (input_thread == NULL) {
    fprintf (stderr, "error: g_thread_try_new() failed");
    return -1;
  }

  g_main_loop_run (loop);
  g_thread_join (input_thread);

  gst_element_set_state (GST_ELEMENT (pipeline), GST_STATE_NULL);

  gst_object_unref (bus);
  gst_object_unref (pipeline);

  gst_deinit ();

  return 0;

}

static gboolean
gst_hls_demux_cache_fragments (GstHLSDemux * demux)
{
  gint i;

  /* If this playlist is a variant playlist, select the first one
   * and update it */
  if (gst_m3u8_client_has_variant_playlist (demux->client)) {
    GstM3U8 *child = NULL;

    if (demux->connection_speed == 0) {

      GST_M3U8_CLIENT_LOCK (demux->client);
      child = demux->client->main->current_variant->data;
      GST_M3U8_CLIENT_UNLOCK (demux->client);
    } else {
      GList *tmp = gst_m3u8_client_get_playlist_for_bitrate (demux->client,
          demux->connection_speed);

      child = GST_M3U8 (tmp->data);
    }

    gst_m3u8_client_set_current (demux->client, child);
    if (!gst_hls_demux_update_playlist (demux, FALSE)) {
      GST_ERROR_OBJECT (demux, "Could not fetch the child playlist %s",
          child->uri);
      return FALSE;
    }
  }

  if (!gst_m3u8_client_is_live (demux->client)) {
    GstClockTime duration = gst_m3u8_client_get_duration (demux->client);

    GST_DEBUG_OBJECT (demux, "Sending duration message : %" GST_TIME_FORMAT,
        GST_TIME_ARGS (duration));
    if (duration != GST_CLOCK_TIME_NONE)
      gst_element_post_message (GST_ELEMENT (demux),
          gst_message_new_duration (GST_OBJECT (demux),
              GST_FORMAT_TIME, duration));
  }

  /* Cache the first fragments */
  for (i = 0; i < demux->fragments_cache; i++) {
    gst_element_post_message (GST_ELEMENT (demux),
        gst_message_new_buffering (GST_OBJECT (demux),
            100 * i / demux->fragments_cache));
    g_get_current_time (&demux->next_update);
    if (!gst_hls_demux_get_next_fragment (demux, TRUE)) {
      if (demux->end_of_playlist)
        break;
      if (!demux->cancelled)
        GST_ERROR_OBJECT (demux, "Error caching the first fragments");
      return FALSE;
    }
    /* make sure we stop caching fragments if something cancelled it */
    if (demux->cancelled)
      return FALSE;
    gst_hls_demux_switch_playlist (demux);
  }
  gst_element_post_message (GST_ELEMENT (demux),
      gst_message_new_buffering (GST_OBJECT (demux), 100));

  g_get_current_time (&demux->next_update);

  demux->need_cache = FALSE;
  return TRUE;

}

static GstFlowReturn
opus_dec_chain_parse_data (GstOpusDec * dec, GstBuffer * buffer)
{
  GstFlowReturn res = GST_FLOW_OK;
  gint size;
  guint8 *data;
  GstBuffer *outbuf;
  gint16 *out_data;
  int n, err;
  int samples;
  unsigned int packet_size;
  GstBuffer *buf;

  if (dec->state == NULL) {
    /* If we did not get any headers, default to 2 channels */
    if (dec->n_channels == 0) {
      GstCaps *caps;
      GST_INFO_OBJECT (dec, "No header, assuming single stream");
      dec->n_channels = 2;
      dec->sample_rate = 48000;
      caps = gst_opus_dec_negotiate (dec);
      GST_INFO_OBJECT (dec, "Setting src caps to %" GST_PTR_FORMAT, caps);
      gst_pad_set_caps (GST_AUDIO_DECODER_SRC_PAD (dec), caps);
      gst_caps_unref (caps);
      /* default stereo mapping */
      dec->channel_mapping_family = 0;
      dec->channel_mapping[0] = 0;
      dec->channel_mapping[1] = 1;
      dec->n_streams = 1;
      dec->n_stereo_streams = 1;
    }

    GST_DEBUG_OBJE