/* GStreamer * Copyright (C) 2009 Edward Hervey * 2009 Nokia Corporation * * 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., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ /** * SECTION:gstdiscoverer * @short_description: Utility for discovering information on URIs. * * The #GstDiscoverer is a utility object which allows to get as much * information as possible from one or many URIs. * * It provides two APIs, allowing usage in blocking or non-blocking mode. * * The blocking mode just requires calling gst_discoverer_discover_uri() * with the URI one wishes to discover. * * The non-blocking mode requires a running #GMainLoop in the default * #GMainContext, where one connects to the various signals, appends the * URIs to be processed (through gst_discoverer_discover_uri_async()) and then * asks for the discovery to begin (through gst_discoverer_start()). * * All the information is returned in a #GstDiscovererInfo structure. * * Since: 0.10.31 */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include "pbutils.h" #include "pbutils-marshal.h" #include "pbutils-private.h" #include "gst/glib-compat-private.h" GST_DEBUG_CATEGORY_STATIC (discoverer_debug); #define GST_CAT_DEFAULT discoverer_debug static GQuark _CAPS_QUARK; static GQuark _TAGS_QUARK; static GQuark _MISSING_PLUGIN_QUARK; static GQuark _STREAM_TOPOLOGY_QUARK; static GQuark _TOPOLOGY_PAD_QUARK; typedef struct { GstDiscoverer *dc; GstPad *pad; GstElement *queue; GstElement *sink; GstTagList *tags; } PrivateStream; struct _GstDiscovererPrivate { gboolean async; /* allowed time to discover each uri in nanoseconds */ GstClockTime timeout; /* list of pending URI to process (current excluded) */ GList *pending_uris; GMutex *lock; /* TRUE if processing a URI */ gboolean processing; /* TRUE if discoverer has been started */ gboolean running; /* current items */ GstDiscovererInfo *current_info; GError *current_error; GstStructure *current_topology; /* List of private streams */ GList *streams; /* Global elements */ GstBin *pipeline; GstElement *uridecodebin; GstBus *bus; GType decodebin_type; /* Custom main context variables */ GMainContext *ctx; guint sourceid; guint timeoutid; /* reusable queries */ GstQuery *seeking_query; /* Handler ids for various callbacks */ gulong pad_added_id; gulong pad_remove_id; gulong element_added_id; gulong bus_cb_id; }; #define DISCO_LOCK(dc) g_mutex_lock (dc->priv->lock); #define DISCO_UNLOCK(dc) g_mutex_unlock (dc->priv->lock); static void _do_init (void) { GST_DEBUG_CATEGORY_INIT (discoverer_debug, "discoverer", 0, "Discoverer"); _CAPS_QUARK = g_quark_from_static_string ("caps"); _TAGS_QUARK = g_quark_from_static_string ("tags"); _MISSING_PLUGIN_QUARK = g_quark_from_static_string ("missing-plugin"); _STREAM_TOPOLOGY_QUARK = g_quark_from_static_string ("stream-topology"); _TOPOLOGY_PAD_QUARK = g_quark_from_static_string ("pad"); }; G_DEFINE_TYPE_EXTENDED (GstDiscoverer, gst_discoverer, G_TYPE_OBJECT, 0, _do_init ()); enum { SIGNAL_FINISHED, SIGNAL_STARTING, SIGNAL_DISCOVERED, LAST_SIGNAL }; #define DEFAULT_PROP_TIMEOUT 15 * GST_SECOND enum { PROP_0, PROP_TIMEOUT }; static guint gst_discoverer_signals[LAST_SIGNAL] = { 0 }; static void gst_discoverer_set_timeout (GstDiscoverer * dc, GstClockTime timeout); static gboolean async_timeout_cb (GstDiscoverer * dc); static void discoverer_bus_cb (GstBus * bus, GstMessage * msg, GstDiscoverer * dc); static void uridecodebin_pad_added_cb (GstElement * uridecodebin, GstPad * pad, GstDiscoverer * dc); static void uridecodebin_pad_removed_cb (GstElement * uridecodebin, GstPad * pad, GstDiscoverer * dc); static void gst_discoverer_dispose (GObject * dc); static void gst_discoverer_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec); static void gst_discoverer_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec); static void gst_discoverer_class_init (GstDiscovererClass * klass) { GObjectClass *gobject_class = (GObjectClass *) klass; gobject_class->dispose = gst_discoverer_dispose; gobject_class->set_property = gst_discoverer_set_property; gobject_class->get_property = gst_discoverer_get_property; g_type_class_add_private (klass, sizeof (GstDiscovererPrivate)); /* properties */ /** * GstDiscoverer:timeout * * The duration (in nanoseconds) after which the discovery of an individual * URI will timeout. * * If the discovery of a URI times out, the %GST_DISCOVERER_TIMEOUT will be * set on the result flags. */ g_object_class_install_property (gobject_class, PROP_TIMEOUT, g_param_spec_uint64 ("timeout", "timeout", "Timeout", GST_SECOND, 3600 * GST_SECOND, DEFAULT_PROP_TIMEOUT, G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS)); /* signals */ /** * GstDiscoverer::finished: * @discoverer: the #GstDiscoverer * * Will be emitted when all pending URIs have been processed. */ gst_discoverer_signals[SIGNAL_FINISHED] = g_signal_new ("finished", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstDiscovererClass, finished), NULL, NULL, g_cclosure_marshal_VOID__VOID, G_TYPE_NONE, 0, G_TYPE_NONE); /** * GstDiscoverer::starting: * @discoverer: the #GstDiscoverer * * Will be emitted when the discover starts analyzing the pending URIs */ gst_discoverer_signals[SIGNAL_STARTING] = g_signal_new ("starting", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstDiscovererClass, starting), NULL, NULL, g_cclosure_marshal_VOID__VOID, G_TYPE_NONE, 0, G_TYPE_NONE); /** * GstDiscoverer::discovered: * @discoverer: the #GstDiscoverer * @info: the results #GstDiscovererInfo * @error: (type GLib.Error): #GError, which will be non-NULL if an error * occurred during discovery * * Will be emitted when all information on a URI could be discovered. */ gst_discoverer_signals[SIGNAL_DISCOVERED] = g_signal_new ("discovered", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstDiscovererClass, discovered), NULL, NULL, pbutils_marshal_VOID__POINTER_BOXED, G_TYPE_NONE, 2, GST_TYPE_DISCOVERER_INFO, G_TYPE_ERROR | G_SIGNAL_TYPE_STATIC_SCOPE); } static void uridecodebin_element_added_cb (GstElement * uridecodebin, GstElement * child, GstDiscoverer * dc) { GST_DEBUG ("New element added to uridecodebin : %s", GST_ELEMENT_NAME (child)); if (G_OBJECT_TYPE (child) == dc->priv->decodebin_type) { g_object_set (child, "post-stream-topology", TRUE, NULL); } } static void gst_discoverer_init (GstDiscoverer * dc) { GstElement *tmp; GstFormat format = GST_FORMAT_TIME; dc->priv = G_TYPE_INSTANCE_GET_PRIVATE (dc, GST_TYPE_DISCOVERER, GstDiscovererPrivate); dc->priv->timeout = DEFAULT_PROP_TIMEOUT; dc->priv->async = FALSE; dc->priv->lock = g_mutex_new (); GST_LOG ("Creating pipeline"); dc->priv->pipeline = (GstBin *) gst_pipeline_new ("Discoverer"); GST_LOG_OBJECT (dc, "Creating uridecodebin"); dc->priv->uridecodebin = gst_element_factory_make ("uridecodebin", "discoverer-uri"); if (G_UNLIKELY (dc->priv->uridecodebin == NULL)) { GST_ERROR ("Can't create uridecodebin"); return; } GST_LOG_OBJECT (dc, "Adding uridecodebin to pipeline"); gst_bin_add (dc->priv->pipeline, dc->priv->uridecodebin); dc->priv->pad_added_id = g_signal_connect_object (dc->priv->uridecodebin, "pad-added", G_CALLBACK (uridecodebin_pad_added_cb), dc, 0); dc->priv->pad_remove_id = g_signal_connect_object (dc->priv->uridecodebin, "pad-removed", G_CALLBACK (uridecodebin_pad_removed_cb), dc, 0); GST_LOG_OBJECT (dc, "Getting pipeline bus"); dc->priv->bus = gst_pipeline_get_bus ((GstPipeline *) dc->priv->pipeline); dc->priv->bus_cb_id = g_signal_connect_object (dc->priv->bus, "message", G_CALLBACK (discoverer_bus_cb), dc, 0); GST_DEBUG_OBJECT (dc, "Done initializing Discoverer"); /* This is ugly. We get the GType of decodebin so we can quickly detect * when a decodebin is added to uridecodebin so we can set the * post-stream-topology setting to TRUE */ dc->priv->element_added_id = g_signal_connect_object (dc->priv->uridecodebin, "element-added", G_CALLBACK (uridecodebin_element_added_cb), dc, 0); tmp = gst_element_factory_make ("decodebin", NULL); dc->priv->decodebin_type = G_OBJECT_TYPE (tmp); gst_object_unref (tmp); /* create queries */ dc->priv->seeking_query = gst_query_new_seeking (format); } static void discoverer_reset (GstDiscoverer * dc) { GST_DEBUG_OBJECT (dc, "Resetting"); if (dc->priv->pending_uris) { g_list_foreach (dc->priv->pending_uris, (GFunc) g_free, NULL); g_list_free (dc->priv->pending_uris); dc->priv->pending_uris = NULL; } if (dc->priv->pipeline) gst_element_set_state ((GstElement *) dc->priv->pipeline, GST_STATE_NULL); } #define DISCONNECT_SIGNAL(o,i) G_STMT_START{ \ if ((i) && g_signal_handler_is_connected ((o), (i))) \ g_signal_handler_disconnect ((o), (i)); \ (i) = 0; \ }G_STMT_END static void gst_discoverer_dispose (GObject * obj) { GstDiscoverer *dc = (GstDiscoverer *) obj; GST_DEBUG_OBJECT (dc, "Disposing"); discoverer_reset (dc); if (G_LIKELY (dc->priv->pipeline)) { /* Workaround for bug #118536 */ DISCONNECT_SIGNAL (dc->priv->uridecodebin, dc->priv->pad_added_id); DISCONNECT_SIGNAL (dc->priv->uridecodebin, dc->priv->pad_remove_id); DISCONNECT_SIGNAL (dc->priv->uridecodebin, dc->priv->element_added_id); DISCONNECT_SIGNAL (dc->priv->bus, dc->priv->bus_cb_id); /* pipeline was set to NULL in _reset */ gst_object_unref (dc->priv->pipeline); gst_object_unref (dc->priv->bus); dc->priv->pipeline = NULL; dc->priv->uridecodebin = NULL; dc->priv->bus = NULL; } gst_discoverer_stop (dc); if (dc->priv->lock) { g_mutex_free (dc->priv->lock); dc->priv->lock = NULL; } if (dc->priv->seeking_query) { gst_query_unref (dc->priv->seeking_query); dc->priv->seeking_query = NULL; } G_OBJECT_CLASS (gst_discoverer_parent_class)->dispose (obj); } static void gst_discoverer_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec) { GstDiscoverer *dc = (GstDiscoverer *) object; switch (prop_id) { case PROP_TIMEOUT: gst_discoverer_set_timeout (dc, g_value_get_uint64 (value)); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void gst_discoverer_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec) { GstDiscoverer *dc = (GstDiscoverer *) object; switch (prop_id) { case PROP_TIMEOUT: DISCO_LOCK (dc); g_value_set_uint64 (value, dc->priv->timeout); DISCO_UNLOCK (dc); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void gst_discoverer_set_timeout (GstDiscoverer * dc, GstClockTime timeout) { GST_DEBUG_OBJECT (dc, "timeout : %" GST_TIME_FORMAT, GST_TIME_ARGS (timeout)); /* FIXME : update current pending timeout if we're running */ DISCO_LOCK (dc); dc->priv->timeout = timeout; DISCO_UNLOCK (dc); } static GstPadProbeReturn _event_probe (GstPad * pad, GstPadProbeInfo * info, PrivateStream * ps) { GstEvent *event = GST_PAD_PROBE_INFO_EVENT (info); if (GST_EVENT_TYPE (event) == GST_EVENT_TAG) { GstTagList *tl = NULL, *tmp; gst_event_parse_tag (event, &tl); GST_DEBUG_OBJECT (pad, "tags %" GST_PTR_FORMAT, tl); DISCO_LOCK (ps->dc); /* If preroll is complete, drop these tags - the collected information is * possibly already being processed and adding more tags would be racy */ if (G_LIKELY (ps->dc->priv->processing)) { GST_DEBUG_OBJECT (pad, "private stream %p old tags %" GST_PTR_FORMAT, ps, ps->tags); tmp = gst_tag_list_merge (ps->tags, tl, GST_TAG_MERGE_APPEND); if (ps->tags) gst_tag_list_free (ps->tags); ps->tags = tmp; GST_DEBUG_OBJECT (pad, "private stream %p new tags %" GST_PTR_FORMAT, ps, tmp); } else GST_DEBUG_OBJECT (pad, "Dropping tags since preroll is done"); DISCO_UNLOCK (ps->dc); } return GST_PAD_PROBE_OK; } static GstStaticCaps subtitle_caps = GST_STATIC_CAPS ("text/plain; " "text/x-pango-markup; subpicture/x-pgs; subpicture/x-dvb; " "application/x-subtitle-unknown; application/x-ssa; application/x-ass; " "subtitle/x-kate; application/x-kate; video/x-dvd-subpicture"); static gboolean is_subtitle_caps (const GstCaps * caps) { GstCaps *subs_caps; gboolean ret; subs_caps = gst_static_caps_get (&subtitle_caps); ret = gst_caps_can_intersect (caps, subs_caps); gst_caps_unref (subs_caps); return ret; } static void uridecodebin_pad_added_cb (GstElement * uridecodebin, GstPad * pad, GstDiscoverer * dc) { PrivateStream *ps; GstPad *sinkpad = NULL; GstCaps *caps; GST_DEBUG_OBJECT (dc, "pad %s:%s", GST_DEBUG_PAD_NAME (pad)); ps = g_slice_new0 (PrivateStream); ps->dc = dc; ps->pad = pad; ps->queue = gst_element_factory_make ("queue", NULL); ps->sink = gst_element_factory_make ("fakesink", NULL); if (G_UNLIKELY (ps->queue == NULL || ps->sink == NULL)) goto error; g_object_set (ps->sink, "silent", TRUE, NULL); g_object_set (ps->queue, "max-size-buffers", 1, "silent", TRUE, NULL); caps = gst_pad_query_caps (pad, NULL); if (is_subtitle_caps (caps)) { /* Subtitle streams are sparse and may not provide any information - don't * wait for data to preroll */ g_object_set (ps->sink, "async", FALSE, NULL); } gst_caps_unref (caps); gst_bin_add_many (dc->priv->pipeline, ps->queue, ps->sink, NULL); if (!gst_element_link_pads_full (ps->queue, "src", ps->sink, "sink", GST_PAD_LINK_CHECK_NOTHING)) goto error; if (!gst_element_sync_state_with_parent (ps->sink)) goto error; if (!gst_element_sync_state_with_parent (ps->queue)) goto error; sinkpad = gst_element_get_static_pad (ps->queue, "sink"); if (sinkpad == NULL) goto error; if (gst_pad_link_full (pad, sinkpad, GST_PAD_LINK_CHECK_NOTHING) != GST_PAD_LINK_OK) goto error; gst_object_unref (sinkpad); /* Add an event probe */ gst_pad_add_probe (pad, GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM, (GstPadProbeCallback) _event_probe, ps, NULL); DISCO_LOCK (dc); dc->priv->streams = g_list_append (dc->priv->streams, ps); DISCO_UNLOCK (dc); GST_DEBUG_OBJECT (dc, "Done handling pad"); return; error: GST_ERROR_OBJECT (dc, "Error while handling pad"); if (sinkpad) gst_object_unref (sinkpad); if (ps->queue) gst_object_unref (ps->queue); if (ps->sink) gst_object_unref (ps->sink); g_slice_free (PrivateStream, ps); return; } static void uridecodebin_pad_removed_cb (GstElement * uridecodebin, GstPad * pad, GstDiscoverer * dc) { GList *tmp; PrivateStream *ps; GstPad *sinkpad; GST_DEBUG_OBJECT (dc, "pad %s:%s", GST_DEBUG_PAD_NAME (pad)); /* Find the PrivateStream */ DISCO_LOCK (dc); for (tmp = dc->priv->streams; tmp; tmp = tmp->next) { ps = (PrivateStream *) tmp->data; if (ps->pad == pad) break; } if (tmp == NULL) { DISCO_UNLOCK (dc); GST_DEBUG ("The removed pad wasn't controlled by us !"); return; } dc->priv->streams = g_list_delete_link (dc->priv->streams, tmp); DISCO_UNLOCK (dc); gst_element_set_state (ps->sink, GST_STATE_NULL); gst_element_set_state (ps->queue, GST_STATE_NULL); gst_element_unlink (ps->queue, ps->sink); sinkpad = gst_element_get_static_pad (ps->queue, "sink"); gst_pad_unlink (pad, sinkpad); gst_object_unref (sinkpad); /* references removed here */ gst_bin_remove_many (dc->priv->pipeline, ps->sink, ps->queue, NULL); if (ps->tags) { gst_tag_list_free (ps->tags); } g_slice_free (PrivateStream, ps); GST_DEBUG ("Done handling pad"); } static GstStructure * collect_stream_information (GstDiscoverer * dc, PrivateStream * ps, guint idx) { GstCaps *caps; GstStructure *st; gchar *stname; stname = g_strdup_printf ("stream-%02d", idx); st = gst_structure_new_empty (stname); g_free (stname); /* Get caps */ caps = gst_pad_get_current_caps (ps->pad); if (!caps) { GST_WARNING ("Couldn't get negotiated caps from %s:%s", GST_DEBUG_PAD_NAME (ps->pad)); caps = gst_pad_query_caps (ps->pad, NULL); } if (caps) { GST_DEBUG ("Got caps %" GST_PTR_FORMAT, caps); gst_structure_id_set (st, _CAPS_QUARK, GST_TYPE_CAPS, caps, NULL); gst_caps_unref (caps); } if (ps->tags) gst_structure_id_set (st, _TAGS_QUARK, GST_TYPE_TAG_LIST, ps->tags, NULL); return st; } /* takes ownership of new_tags, may replace *taglist with a new one */ static void gst_discoverer_merge_and_replace_tags (GstTagList ** taglist, GstTagList * new_tags) { if (new_tags == NULL) return; if (*taglist == NULL) { *taglist = new_tags; return; } gst_tag_list_insert (*taglist, new_tags, GST_TAG_MERGE_REPLACE); gst_tag_list_free (new_tags); } /* Parses a set of caps and tags in st and populates a GstDiscovererStreamInfo * structure (parent, if !NULL, otherwise it allocates one) */ static GstDiscovererStreamInfo * collect_information (GstDiscoverer * dc, const GstStructure * st, GstDiscovererStreamInfo * parent) { GstCaps *caps; GstStructure *caps_st; GstTagList *tags_st; const gchar *name; int tmp; guint utmp; if (!st || !gst_structure_id_has_field (st, _CAPS_QUARK)) { GST_WARNING ("Couldn't find caps !"); if (parent) return gst_discoverer_stream_info_ref (parent); else return (GstDiscovererStreamInfo *) g_object_new (GST_TYPE_DISCOVERER_STREAM_INFO, NULL); } gst_structure_id_get (st, _CAPS_QUARK, GST_TYPE_CAPS, &caps, NULL); caps_st = gst_caps_get_structure (caps, 0); name = gst_structure_get_name (caps_st); if (g_str_has_prefix (name, "audio/")) { GstDiscovererAudioInfo *info; if (parent) info = (GstDiscovererAudioInfo *) gst_discoverer_stream_info_ref (parent); else { info = (GstDiscovererAudioInfo *) g_object_new (GST_TYPE_DISCOVERER_AUDIO_INFO, NULL); info->parent.caps = gst_caps_ref (caps); } if (gst_structure_get_int (caps_st, "rate", &tmp)) info->sample_rate = (guint) tmp; if (gst_structure_get_int (caps_st, "channels", &tmp)) info->channels = (guint) tmp; if (gst_structure_get_int (caps_st, "depth", &tmp)) info->depth = (guint) tmp; if (gst_structure_id_has_field (st, _TAGS_QUARK)) { gst_structure_id_get (st, _TAGS_QUARK, GST_TYPE_TAG_LIST, &tags_st, NULL); if (gst_tag_list_get_uint (tags_st, GST_TAG_BITRATE, &utmp) || gst_tag_list_get_uint (tags_st, GST_TAG_NOMINAL_BITRATE, &utmp)) info->bitrate = utmp; if (gst_tag_list_get_uint (tags_st, GST_TAG_MAXIMUM_BITRATE, &utmp)) info->max_bitrate = utmp; /* FIXME: Is it worth it to remove the tags we've parsed? */ gst_discoverer_merge_and_replace_tags (&info->parent.tags, tags_st); } if (!info->language && ((GstDiscovererStreamInfo *) info)->tags) { gchar *language; if (gst_tag_list_get_string (((GstDiscovererStreamInfo *) info)->tags, GST_TAG_LANGUAGE_CODE, &language)) { info->language = language; } } gst_caps_unref (caps); return (GstDiscovererStreamInfo *) info; } else if (g_str_has_prefix (name, "video/") || g_str_has_prefix (name, "image/")) { GstDiscovererVideoInfo *info; GstVideoInfo vinfo; if (parent) info = (GstDiscovererVideoInfo *) gst_discoverer_stream_info_ref (parent); else { info = (GstDiscovererVideoInfo *) g_object_new (GST_TYPE_DISCOVERER_VIDEO_INFO, NULL); info->parent.caps = gst_caps_ref (caps); } /* FIXME : gst_video_info_from_caps only works with raw caps, * wouldn't we want to get all the info below for non-raw caps ? */ if (g_str_has_prefix (name, "video/x-raw") && gst_video_info_from_caps (&vinfo, caps)) { info->width = (guint) vinfo.width; info->height = (guint) vinfo.height; info->depth = (guint) 0; info->par_num = vinfo.par_n; info->par_denom = vinfo.par_d; info->framerate_num = vinfo.fps_n; info->framerate_denom = vinfo.fps_d; info->interlaced = (vinfo.flags & GST_VIDEO_FLAG_INTERLACED) != 0; } if (gst_structure_id_has_field (st, _TAGS_QUARK)) { gst_structure_id_get (st, _TAGS_QUARK, GST_TYPE_TAG_LIST, &tags_st, NULL); if (gst_tag_list_get_uint (tags_st, GST_TAG_BITRATE, &utmp) || gst_tag_list_get_uint (tags_st, GST_TAG_NOMINAL_BITRATE, &utmp)) info->bitrate = utmp; if (gst_tag_list_get_uint (tags_st, GST_TAG_MAXIMUM_BITRATE, &utmp)) info->max_bitrate = utmp; /* FIXME: Is it worth it to remove the tags we've parsed? */ gst_discoverer_merge_and_replace_tags (&info->parent.tags, (GstTagList *) tags_st); } gst_caps_unref (caps); return (GstDiscovererStreamInfo *) info; } else if (is_subtitle_caps (caps)) { GstDiscovererSubtitleInfo *info; if (parent) info = (GstDiscovererSubtitleInfo *) gst_discoverer_stream_info_ref (parent); else { info = (GstDiscovererSubtitleInfo *) g_object_new (GST_TYPE_DISCOVERER_SUBTITLE_INFO, NULL); info->parent.caps = gst_caps_ref (caps); } if (gst_structure_id_has_field (st, _TAGS_QUARK)) { const gchar *language; gst_structure_id_get (st, _TAGS_QUARK, GST_TYPE_TAG_LIST, &tags_st, NULL); language = gst_structure_get_string (caps_st, GST_TAG_LANGUAGE_CODE); if (language) info->language = g_strdup (language); /* FIXME: Is it worth it to remove the tags we've parsed? */ gst_discoverer_merge_and_replace_tags (&info->parent.tags, tags_st); } if (!info->language && ((GstDiscovererStreamInfo *) info)->tags) { gchar *language; if (gst_tag_list_get_string (((GstDiscovererStreamInfo *) info)->tags, GST_TAG_LANGUAGE_CODE, &language)) { info->language = language; } } gst_caps_unref (caps); return (GstDiscovererStreamInfo *) info; } else { /* None of the above - populate what information we can */ GstDiscovererStreamInfo *info; if (parent) info = gst_discoverer_stream_info_ref (parent); else { info = (GstDiscovererStreamInfo *) g_object_new (GST_TYPE_DISCOVERER_STREAM_INFO, NULL); info->caps = gst_caps_ref (caps); } if (gst_structure_id_get (st, _TAGS_QUARK, GST_TYPE_TAG_LIST, &tags_st, NULL)) { gst_discoverer_merge_and_replace_tags (&info->tags, tags_st); } gst_caps_unref (caps); return info; } } static GstStructure * find_stream_for_node (GstDiscoverer * dc, const GstStructure * topology) { GstPad *pad; GstPad *target_pad = NULL; GstStructure *st = NULL; PrivateStream *ps; guint i; GList *tmp; if (!gst_structure_id_has_field (topology, _TOPOLOGY_PAD_QUARK)) { GST_DEBUG ("Could not find pad for node %" GST_PTR_FORMAT "\n", topology); return NULL; } gst_structure_id_get (topology, _TOPOLOGY_PAD_QUARK, GST_TYPE_PAD, &pad, NULL); if (!dc->priv->streams) { gst_object_unref (pad); return NULL; } for (i = 0, tmp = dc->priv->streams; tmp; tmp = tmp->next, i++) { ps = (PrivateStream *) tmp->data; target_pad = gst_ghost_pad_get_target (GST_GHOST_PAD (ps->pad)); gst_object_unref (target_pad); if (target_pad == pad) break; } if (tmp) st = collect_stream_information (dc, ps, i); gst_object_unref (pad); return st; } static gboolean child_is_raw_stream (const GstCaps * parent, const GstCaps * child) { const GstStructure *st1, *st2; const gchar *name1, *name2; st1 = gst_caps_get_structure (parent, 0); name1 = gst_structure_get_name (st1); st2 = gst_caps_get_structure (child, 0); name2 = gst_structure_get_name (st2); if ((g_str_has_prefix (name1, "audio/") && g_str_has_prefix (name2, "audio/x-raw")) || ((g_str_has_prefix (name1, "video/") || g_str_has_prefix (name1, "image/")) && g_str_has_prefix (name2, "video/x-raw"))) { /* child is the "raw" sub-stream corresponding to parent */ return TRUE; } if (is_subtitle_caps (parent)) return TRUE; return FALSE; } /* If a parent is non-NULL, collected stream information will be appended to it * (and where the information exists, it will be overriden) */ static GstDiscovererStreamInfo * parse_stream_topology (GstDiscoverer * dc, const GstStructure * topology, GstDiscovererStreamInfo * parent) { GstDiscovererStreamInfo *res = NULL; GstCaps *caps = NULL; const GValue *nval = NULL; GST_DEBUG ("parsing: %" GST_PTR_FORMAT, topology); nval = gst_structure_get_value (topology, "next"); if (nval == NULL || GST_VALUE_HOLDS_STRUCTURE (nval)) { GstStructure *st = find_stream_for_node (dc, topology); gboolean add_to_list = TRUE; if (st) { res = collect_information (dc, st, parent); gst_structure_free (st); } else { /* Didn't find a stream structure, so let's just use the caps we have */ res = collect_information (dc, topology, parent); } if (nval == NULL) { /* FIXME : aggregate with information from main streams */ GST_DEBUG ("Coudn't find 'next' ! might be the last entry"); } else { GstCaps *caps; const GstStructure *st; st = gst_value_get_structure (nval); GST_DEBUG ("next is a structure %" GST_PTR_FORMAT, st); if (!parent) parent = res; if (gst_structure_id_get (st, _CAPS_QUARK, GST_TYPE_CAPS, &caps, NULL)) { if (gst_caps_can_intersect (parent->caps, caps)) { /* We sometimes get an extra sub-stream from the parser. If this is * the case, we just replace the parent caps with this stream's caps * since they might contain more information */ gst_caps_replace (&parent->caps, caps); parse_stream_topology (dc, st, parent); add_to_list = FALSE; } else if (child_is_raw_stream (parent->caps, caps)) { /* This is the "raw" stream corresponding to the parent. This * contains more information than the parent, tags etc. */ parse_stream_topology (dc, st, parent); add_to_list = FALSE; } else { GstDiscovererStreamInfo *next = parse_stream_topology (dc, st, NULL); res->next = next; next->previous = res; } gst_caps_unref (caps); } } if (add_to_list) { dc->priv->current_info->stream_list = g_list_append (dc->priv->current_info->stream_list, res); } else { gst_discoverer_stream_info_unref (res); } } else if (GST_VALUE_HOLDS_LIST (nval)) { guint i, len; GstDiscovererContainerInfo *cont; GstTagList *tags; if (!gst_structure_id_get (topology, _CAPS_QUARK, GST_TYPE_CAPS, &caps, NULL)) GST_WARNING ("Couldn't find caps !"); len = gst_value_list_get_size (nval); GST_DEBUG ("next is a list of %d entries", len); cont = (GstDiscovererContainerInfo *) g_object_new (GST_TYPE_DISCOVERER_CONTAINER_INFO, NULL); cont->parent.caps = caps; res = (GstDiscovererStreamInfo *) cont; if (gst_structure_id_has_field (topology, _TAGS_QUARK)) { GstTagList *tmp; gst_structure_id_get (topology, _TAGS_QUARK, GST_TYPE_TAG_LIST, &tags, NULL); GST_DEBUG ("Merge tags %" GST_PTR_FORMAT, tags); tmp = gst_tag_list_merge (cont->parent.tags, (GstTagList *) tags, GST_TAG_MERGE_APPEND); gst_tag_list_free (tags); if (cont->parent.tags) gst_tag_list_free (cont->parent.tags); cont->parent.tags = tmp; GST_DEBUG ("Container info tags %" GST_PTR_FORMAT, tmp); } for (i = 0; i < len; i++) { const GValue *subv = gst_value_list_get_value (nval, i); const GstStructure *subst = gst_value_get_structure (subv); GstDiscovererStreamInfo *substream; GST_DEBUG ("%d %" GST_PTR_FORMAT, i, subst); substream = parse_stream_topology (dc, subst, NULL); substream->previous = res; cont->streams = g_list_append (cont->streams, gst_discoverer_stream_info_ref (substream)); } } return res; } /* Called when pipeline is pre-rolled */ static void discoverer_collect (GstDiscoverer * dc) { GST_DEBUG ("Collecting information"); /* Stop the timeout handler if present */ if (dc->priv->timeoutid) { g_source_remove (dc->priv->timeoutid); dc->priv->timeoutid = 0; } if (dc->priv->streams) { /* FIXME : Make this querying optional */ if (TRUE) { GstElement *pipeline = (GstElement *) dc->priv->pipeline; gint64 dur; GST_DEBUG ("Attempting to query duration"); if (gst_element_query_duration (pipeline, GST_FORMAT_TIME, &dur)) { GST_DEBUG ("Got duration %" GST_TIME_FORMAT, GST_TIME_ARGS (dur)); dc->priv->current_info->duration = (guint64) dur; } else { GstStateChangeReturn sret; /* Some parsers may not even return a rough estimate right away, e.g. * because they've only processed a single frame so far, so if we * didn't get a duration the first time, spin a bit and try again. * Ugly, but still better than making parsers or other elements return * completely bogus values. We need some API extensions to solve this * better. */ GST_INFO ("No duration yet, try a bit harder.."); sret = gst_element_set_state (pipeline, GST_STATE_PLAYING); if (sret != GST_STATE_CHANGE_FAILURE) { int i; for (i = 0; i < 2; ++i) { g_usleep (G_USEC_PER_SEC / 20); if (gst_element_query_duration (pipeline, GST_FORMAT_TIME, &dur) && dur > 0) { GST_DEBUG ("Got duration %" GST_TIME_FORMAT, GST_TIME_ARGS (dur)); dc->priv->current_info->duration = (guint64) dur; break; } } gst_element_set_state (pipeline, GST_STATE_PAUSED); } } if (dc->priv->seeking_query) { if (gst_element_query (pipeline, dc->priv->seeking_query)) { GstFormat format; gboolean seekable; gst_query_parse_seeking (dc->priv->seeking_query, &format, &seekable, NULL, NULL); if (format == GST_FORMAT_TIME) { GST_DEBUG ("Got seekable %d", seekable); dc->priv->current_info->seekable = seekable; } } } } if (dc->priv->current_topology) dc->priv->current_info->stream_info = parse_stream_topology (dc, dc->priv->current_topology, NULL); /* * Images need some special handling. They do not have a duration, have * caps named image/ (th exception being MJPEG video which is also * type image/jpeg), and should consist of precisely one stream (actually * initially there are 2, the image and raw stream, but we squash these * while parsing the stream topology). At some point, if we find that these * conditions are not sufficient, we can count the number of decoders and * parsers in the chain, and if there's more than one decoder, or any * parser at all, we should not mark this as an image. */ if (dc->priv->current_info->duration == 0 && dc->priv->current_info->stream_info != NULL && dc->priv->current_info->stream_info->next == NULL) { GstStructure *st = gst_caps_get_structure (dc->priv->current_info->stream_info->caps, 0); if (g_str_has_prefix (gst_structure_get_name (st), "image/")) ((GstDiscovererVideoInfo *) dc->priv->current_info-> stream_info)->is_image = TRUE; } } if (dc->priv->async) { GST_DEBUG ("Emitting 'discoverered'"); g_signal_emit (dc, gst_discoverer_signals[SIGNAL_DISCOVERED], 0, dc->priv->current_info, dc->priv->current_error); /* Clients get a copy of current_info since it is a boxed type */ gst_discoverer_info_unref (dc->priv->current_info); } } static void get_async_cb (gpointer cb_data, GSource * source, GSourceFunc * func, gpointer * data) { *func = (GSourceFunc) async_timeout_cb; *data = cb_data; } /* Wrapper since GSourceCallbackFuncs don't expect a return value from ref() */ static void _void_g_object_ref (gpointer object) { g_object_ref (G_OBJECT (object)); } static void handle_current_async (GstDiscoverer * dc) { GSource *source; static GSourceCallbackFuncs cb_funcs = { _void_g_object_ref, g_object_unref, get_async_cb, }; /* Attach a timeout to the main context */ source = g_timeout_source_new (dc->priv->timeout / GST_MSECOND); g_source_set_callback_indirect (source, g_object_ref (dc), &cb_funcs); dc->priv->timeoutid = g_source_attach (source, dc->priv->ctx); g_source_unref (source); } /* Returns TRUE if processing should stop */ static gboolean handle_message (GstDiscoverer * dc, GstMessage * msg) { gboolean done = FALSE; GST_DEBUG_OBJECT (GST_MESSAGE_SRC (msg), "got a %s message", GST_MESSAGE_TYPE_NAME (msg)); switch (GST_MESSAGE_TYPE (msg)) { case GST_MESSAGE_ERROR:{ GError *gerr; gchar *debug; gst_message_parse_error (msg, &gerr, &debug); GST_WARNING_OBJECT (GST_MESSAGE_SRC (msg), "Got an error [debug:%s], [message:%s]", debug, gerr->message); dc->priv->current_error = gerr; g_free (debug); /* We need to stop */ done = TRUE; GST_DEBUG ("Setting result to ERROR"); dc->priv->current_info->result = GST_DISCOVERER_ERROR; } break; case GST_MESSAGE_EOS: GST_DEBUG ("Got EOS !"); done = TRUE; break; case GST_MESSAGE_ASYNC_DONE: if (GST_MESSAGE_SRC (msg) == (GstObject *) dc->priv->pipeline) { GST_DEBUG ("Finished changing state asynchronously"); done = TRUE; } break; case GST_MESSAGE_ELEMENT: { GQuark sttype; const GstStructure *structure; structure = gst_message_get_structure (msg); sttype = gst_structure_get_name_id (structure); GST_DEBUG_OBJECT (GST_MESSAGE_SRC (msg), "structure %" GST_PTR_FORMAT, structure); if (sttype == _MISSING_PLUGIN_QUARK) { GST_DEBUG_OBJECT (GST_MESSAGE_SRC (msg), "Setting result to MISSING_PLUGINS"); dc->priv->current_info->result = GST_DISCOVERER_MISSING_PLUGINS; if (dc->priv->current_info->misc) gst_structure_free (dc->priv->current_info->misc); dc->priv->current_info->misc = gst_structure_copy (structure); } else if (sttype == _STREAM_TOPOLOGY_QUARK) { if (dc->priv->current_topology) gst_structure_free (dc->priv->current_topology); dc->priv->current_topology = gst_structure_copy (structure); } } break; case GST_MESSAGE_TAG: { GstTagList *tl, *tmp; gst_message_parse_tag (msg, &tl); GST_DEBUG_OBJECT (GST_MESSAGE_SRC (msg), "Got tags %" GST_PTR_FORMAT, tl); /* Merge with current tags */ tmp = gst_tag_list_merge (dc->priv->current_info->tags, tl, GST_TAG_MERGE_APPEND); gst_tag_list_free (tl); if (dc->priv->current_info->tags) gst_tag_list_free (dc->priv->current_info->tags); dc->priv->current_info->tags = tmp; GST_DEBUG_OBJECT (GST_MESSAGE_SRC (msg), "Current info %p, tags %" GST_PTR_FORMAT, dc->priv->current_info, tmp); } break; default: break; } return done; } static void handle_current_sync (GstDiscoverer * dc) { GTimer *timer; gdouble deadline = ((gdouble) dc->priv->timeout) / GST_SECOND; GstMessage *msg; gboolean done = FALSE; timer = g_timer_new (); g_timer_start (timer); do { /* poll bus with timeout */ /* FIXME : make the timeout more fine-tuned */ if ((msg = gst_bus_timed_pop (dc->priv->bus, GST_SECOND / 2))) { done = handle_message (dc, msg); gst_message_unref (msg); } } while (!done && (g_timer_elapsed (timer, NULL) < deadline)); /* return result */ if (!done) { GST_DEBUG ("we timed out! Setting result to TIMEOUT"); dc->priv->current_info->result = GST_DISCOVERER_TIMEOUT; } GST_DEBUG ("Done"); g_timer_stop (timer); g_timer_destroy (timer); } static void _setup_locked (GstDiscoverer * dc) { GstStateChangeReturn ret; GST_DEBUG ("Setting up"); /* Pop URI off the pending URI list */ dc->priv->current_info = (GstDiscovererInfo *) g_object_new (GST_TYPE_DISCOVERER_INFO, NULL); dc->priv->current_info->uri = (gchar *) dc->priv->pending_uris->data; dc->priv->pending_uris = g_list_delete_link (dc->priv->pending_uris, dc->priv->pending_uris); /* set uri on uridecodebin */ g_object_set (dc->priv->uridecodebin, "uri", dc->priv->current_info->uri, NULL); GST_DEBUG ("Current is now %s", dc->priv->current_info->uri); dc->priv->processing = TRUE; /* set pipeline to PAUSED */ DISCO_UNLOCK (dc); GST_DEBUG ("Setting pipeline to PAUSED"); ret = gst_element_set_state ((GstElement *) dc->priv->pipeline, GST_STATE_PAUSED); DISCO_LOCK (dc); GST_DEBUG_OBJECT (dc, "Pipeline going to PAUSED : %s", gst_element_state_change_return_get_name (ret)); } static void discoverer_cleanup (GstDiscoverer * dc) { GST_DEBUG ("Cleaning up"); gst_bus_set_flushing (dc->priv->bus, TRUE); gst_element_set_state ((GstElement *) dc->priv->pipeline, GST_STATE_READY); gst_bus_set_flushing (dc->priv->bus, FALSE); DISCO_LOCK (dc); if (dc->priv->current_error) g_error_free (dc->priv->current_error); dc->priv->current_error = NULL; if (dc->priv->current_topology) { gst_structure_free (dc->priv->current_topology); dc->priv->current_topology = NULL; } dc->priv->current_info = NULL; /* Try popping the next uri */ if (dc->priv->async) { if (dc->priv->pending_uris != NULL) { _setup_locked (dc); DISCO_UNLOCK (dc); /* Start timeout */ handle_current_async (dc); } else { /* We're done ! */ DISCO_UNLOCK (dc); g_signal_emit (dc, gst_discoverer_signals[SIGNAL_FINISHED], 0); } } else DISCO_UNLOCK (dc); GST_DEBUG ("out"); } static void discoverer_bus_cb (GstBus * bus, GstMessage * msg, GstDiscoverer * dc) { if (dc->priv->processing) { if (handle_message (dc, msg)) { GST_DEBUG ("Stopping asynchronously"); /* Serialise with _event_probe() */ DISCO_LOCK (dc); dc->priv->processing = FALSE; DISCO_UNLOCK (dc); discoverer_collect (dc); discoverer_cleanup (dc); } } } static gboolean async_timeout_cb (GstDiscoverer * dc) { if (!g_source_is_destroyed (g_main_current_source ())) { dc->priv->timeoutid = 0; GST_DEBUG ("Setting result to TIMEOUT"); dc->priv->current_info->result = GST_DISCOVERER_TIMEOUT; dc->priv->processing = FALSE; discoverer_collect (dc); discoverer_cleanup (dc); } return FALSE; } /* If there is a pending URI, it will pop it from the list of pending * URIs and start the discovery on it. * * Returns GST_DISCOVERER_OK if the next URI was popped and is processing, * else a error flag. */ static GstDiscovererResult start_discovering (GstDiscoverer * dc) { GstDiscovererResult res = GST_DISCOVERER_OK; GST_DEBUG ("Starting"); DISCO_LOCK (dc); if (dc->priv->pending_uris == NULL) { GST_WARNING ("No URI to process"); res = GST_DISCOVERER_URI_INVALID; DISCO_UNLOCK (dc); goto beach; } if (dc->priv->current_info != NULL) { GST_WARNING ("Already processing a file"); res = GST_DISCOVERER_BUSY; DISCO_UNLOCK (dc); goto beach; } g_signal_emit (dc, gst_discoverer_signals[SIGNAL_STARTING], 0); _setup_locked (dc); DISCO_UNLOCK (dc); if (dc->priv->async) handle_current_async (dc); else handle_current_sync (dc); beach: return res; } /** * gst_discoverer_start: * @discoverer: A #GstDiscoverer * * Allow asynchronous discovering of URIs to take place. * A #GMainLoop must be available for #GstDiscoverer to properly work in * asynchronous mode. * * Since: 0.10.31 */ void gst_discoverer_start (GstDiscoverer * discoverer) { GSource *source; GMainContext *ctx = NULL; GST_DEBUG_OBJECT (discoverer, "Starting..."); if (discoverer->priv->async) { GST_DEBUG_OBJECT (discoverer, "We were already started"); return; } discoverer->priv->async = TRUE; discoverer->priv->running = TRUE; ctx = g_main_context_get_thread_default (); /* Connect to bus signals */ if (ctx == NULL) ctx = g_main_context_default (); source = gst_bus_create_watch (discoverer->priv->bus); g_source_set_callback (source, (GSourceFunc) gst_bus_async_signal_func, NULL, NULL); discoverer->priv->sourceid = g_source_attach (source, ctx); g_source_unref (source); discoverer->priv->ctx = g_main_context_ref (ctx); start_discovering (discoverer); GST_DEBUG_OBJECT (discoverer, "Started"); } /** * gst_discoverer_stop: * @discoverer: A #GstDiscoverer * * Stop the discovery of any pending URIs and clears the list of * pending URIS (if any). * * Since: 0.10.31 */ void gst_discoverer_stop (GstDiscoverer * discoverer) { GST_DEBUG_OBJECT (discoverer, "Stopping..."); if (!discoverer->priv->async) { GST_DEBUG_OBJECT (discoverer, "We were already stopped, or running synchronously"); return; } DISCO_LOCK (discoverer); if (discoverer->priv->processing) { /* We prevent any further processing by setting the bus to * flushing and setting the pipeline to READY. * _reset() will take care of the rest of the cleanup */ if (discoverer->priv->bus) gst_bus_set_flushing (discoverer->priv->bus, TRUE); if (discoverer->priv->pipeline) gst_element_set_state ((GstElement *) discoverer->priv->pipeline, GST_STATE_READY); } discoverer->priv->running = FALSE; DISCO_UNLOCK (discoverer); /* Remove timeout handler */ if (discoverer->priv->timeoutid) { g_source_remove (discoverer->priv->timeoutid); discoverer->priv->timeoutid = 0; } /* Remove signal watch */ if (discoverer->priv->sourceid) { g_source_remove (discoverer->priv->sourceid); discoverer->priv->sourceid = 0; } /* Unref main context */ if (discoverer->priv->ctx) { g_main_context_unref (discoverer->priv->ctx); discoverer->priv->ctx = NULL; } discoverer_reset (discoverer); discoverer->priv->async = FALSE; GST_DEBUG_OBJECT (discoverer, "Stopped"); } /** * gst_discoverer_discover_uri_async: * @discoverer: A #GstDiscoverer * @uri: the URI to add. * * Appends the given @uri to the list of URIs to discoverer. The actual * discovery of the @uri will only take place if gst_discoverer_start() has * been called. * * A copy of @uri will be made internally, so the caller can safely g_free() * afterwards. * * Returns: %TRUE if the @uri was successfully appended to the list of pending * uris, else %FALSE * * Since: 0.10.31 */ gboolean gst_discoverer_discover_uri_async (GstDiscoverer * discoverer, const gchar * uri) { gboolean can_run; GST_DEBUG_OBJECT (discoverer, "uri : %s", uri); DISCO_LOCK (discoverer); can_run = (discoverer->priv->pending_uris == NULL); discoverer->priv->pending_uris = g_list_append (discoverer->priv->pending_uris, g_strdup (uri)); DISCO_UNLOCK (discoverer); if (can_run) start_discovering (discoverer); return TRUE; } /* Synchronous mode */ /** * gst_discoverer_discover_uri: * @discoverer: A #GstDiscoverer * @uri: The URI to run on. * @err: (out) (allow-none): If an error occurred, this field will be filled in. * * Synchronously discovers the given @uri. * * A copy of @uri will be made internally, so the caller can safely g_free() * afterwards. * * Returns: (transfer full): the result of the scanning. Can be %NULL if an * error occurred. * * Since: 0.10.31 */ GstDiscovererInfo * gst_discoverer_discover_uri (GstDiscoverer * discoverer, const gchar * uri, GError ** err) { GstDiscovererResult res = 0; GstDiscovererInfo *info; GST_DEBUG_OBJECT (discoverer, "uri:%s", uri); DISCO_LOCK (discoverer); if (G_UNLIKELY (discoverer->priv->current_info)) { DISCO_UNLOCK (discoverer); GST_WARNING_OBJECT (discoverer, "Already handling a uri"); return NULL; } discoverer->priv->pending_uris = g_list_append (discoverer->priv->pending_uris, g_strdup (uri)); DISCO_UNLOCK (discoverer); res = start_discovering (discoverer); discoverer_collect (discoverer); /* Get results */ if (err) { if (discoverer->priv->current_error) *err = g_error_copy (discoverer->priv->current_error); else *err = NULL; } if (res != GST_DISCOVERER_OK) { GST_DEBUG ("Setting result to %d (was %d)", res, discoverer->priv->current_info->result); discoverer->priv->current_info->result = res; } info = discoverer->priv->current_info; discoverer_cleanup (discoverer); return info; } /** * gst_discoverer_new: * @timeout: timeout per file, in nanoseconds. Allowed are values between * one second (#GST_SECOND) and one hour (3600 * #GST_SECOND) * @err: a pointer to a #GError. can be %NULL * * Creates a new #GstDiscoverer with the provided timeout. * * Returns: (transfer full): The new #GstDiscoverer. * If an error occurred when creating the discoverer, @err will be set * accordingly and %NULL will be returned. If @err is set, the caller must * free it when no longer needed using g_error_free(). * * Since: 0.10.31 */ GstDiscoverer * gst_discoverer_new (GstClockTime timeout, GError ** err) { GstDiscoverer *res; res = g_object_new (GST_TYPE_DISCOVERER, "timeout", timeout, NULL); if (res->priv->uridecodebin == NULL) { if (err) *err = g_error_new (GST_CORE_ERROR, GST_CORE_ERROR_MISSING_PLUGIN, "Couldn't create 'uridecodebin' element"); gst_object_unref (res); res = NULL; } return res; }