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Diffstat (limited to 'gst/autodetect/gstautovideosrc.c')
-rw-r--r-- | gst/autodetect/gstautovideosrc.c | 433 |
1 files changed, 433 insertions, 0 deletions
diff --git a/gst/autodetect/gstautovideosrc.c b/gst/autodetect/gstautovideosrc.c new file mode 100644 index 00000000..1a8f768e --- /dev/null +++ b/gst/autodetect/gstautovideosrc.c @@ -0,0 +1,433 @@ +/* GStreamer + * (c) 2005 Ronald S. Bultje <rbultje@ronald.bitfreak.net> + * (c) 2006 Jan Schmidt <thaytan@noraisin.net> + * (c) 2008 Stefan Kost <ensonic@users.sf.net> + * + * 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:element-autovideosrc + * @see_also: autoaudiosrc, v4l2src, v4lsrc + * + * autovideosrc is a video src that automatically detects an appropriate + * video source to use. It does so by scanning the registry for all elements + * that have <quote>Source</quote> and <quote>Video</quote> in the class field + * of their element information, and also have a non-zero autoplugging rank. + * + * <refsect2> + * <title>Example launch line</title> + * |[ + * gst-launch -v -m autovideosrc ! xvimagesink + * ]| + * </refsect2> + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include <string.h> + +#include "gstautovideosrc.h" +#include "gstautodetect.h" + +/* Properties */ +enum +{ + PROP_0, + PROP_CAPS, +}; + +static GstStateChangeReturn +gst_auto_video_src_change_state (GstElement * element, + GstStateChange transition); +static void gst_auto_video_src_dispose (GstAutoVideoSrc * src); +static void gst_auto_video_src_clear_kid (GstAutoVideoSrc * src); + +static void gst_auto_video_src_set_property (GObject * object, guint prop_id, + const GValue * value, GParamSpec * pspec); +static void gst_auto_video_src_get_property (GObject * object, guint prop_id, + GValue * value, GParamSpec * pspec); + +GST_BOILERPLATE (GstAutoVideoSrc, gst_auto_video_src, GstBin, GST_TYPE_BIN); + +static const GstElementDetails gst_auto_video_src_details = +GST_ELEMENT_DETAILS ("Auto video source", + "Source/Video", + "Wrapper video source for automatically detected video source", + "Ronald Bultje <rbultje@ronald.bitfreak.net>\n" + "Jan Schmidt <thaytan@noraisin.net>\n" + "Stefan Kost <ensonic@users.sf.net>"); + +static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src", + GST_PAD_SRC, + GST_PAD_ALWAYS, + GST_STATIC_CAPS_ANY); + +static void +gst_auto_video_src_base_init (gpointer klass) +{ + GstElementClass *eklass = GST_ELEMENT_CLASS (klass); + + gst_element_class_add_pad_template (eklass, + gst_static_pad_template_get (&src_template)); + gst_element_class_set_details (eklass, &gst_auto_video_src_details); +} + +static void +gst_auto_video_src_class_init (GstAutoVideoSrcClass * klass) +{ + GObjectClass *gobject_class; + GstElementClass *eklass = GST_ELEMENT_CLASS (klass); + + gobject_class = G_OBJECT_CLASS (klass); + gobject_class->dispose = + (GObjectFinalizeFunc) GST_DEBUG_FUNCPTR (gst_auto_video_src_dispose); + eklass->change_state = GST_DEBUG_FUNCPTR (gst_auto_video_src_change_state); + gobject_class->set_property = + GST_DEBUG_FUNCPTR (gst_auto_video_src_set_property); + gobject_class->get_property = + GST_DEBUG_FUNCPTR (gst_auto_video_src_get_property); + + /** + * GstAutoVideoSrc:filter-caps + * + * This property will filter out candidate sources that can handle the specified + * caps. By default only video sources that support raw rgb and yuv video + * are selected. + * + * This property can only be set before the element goes to the READY state. + * + * Since: 0.10.11 + **/ + g_object_class_install_property (gobject_class, PROP_CAPS, + g_param_spec_boxed ("filter-caps", "Filter caps", + "Filter src candidates using these caps.", GST_TYPE_CAPS, + G_PARAM_READWRITE)); +} + +static void +gst_auto_video_src_dispose (GstAutoVideoSrc * src) +{ + gst_auto_video_src_clear_kid (src); + + if (src->filter_caps) + gst_caps_unref (src->filter_caps); + src->filter_caps = NULL; + + G_OBJECT_CLASS (parent_class)->dispose ((GObject *) src); +} + +static void +gst_auto_video_src_clear_kid (GstAutoVideoSrc * src) +{ + if (src->kid) { + gst_element_set_state (src->kid, GST_STATE_NULL); + gst_bin_remove (GST_BIN (src), src->kid); + src->kid = NULL; + } +} + +/* + * Hack to make initial linking work; ideally, this'd work even when + * no target has been assigned to the ghostpad yet. + */ + +static void +gst_auto_video_src_reset (GstAutoVideoSrc * src) +{ + GstPad *targetpad; + + /* Remove any existing element */ + gst_auto_video_src_clear_kid (src); + + /* fakesrc placeholder */ + src->kid = gst_element_factory_make ("fakesrc", "tempsrc"); + gst_bin_add (GST_BIN (src), src->kid); + + /* pad */ + targetpad = gst_element_get_static_pad (src->kid, "src"); + gst_ghost_pad_set_target (GST_GHOST_PAD (src->pad), targetpad); + gst_object_unref (targetpad); +} + +static GstStaticCaps raw_caps = + GST_STATIC_CAPS ("video/x-raw-yuv; video/x-raw-rgb"); + +static void +gst_auto_video_src_init (GstAutoVideoSrc * src, GstAutoVideoSrcClass * g_class) +{ + src->pad = gst_ghost_pad_new_no_target ("src", GST_PAD_SRC); + gst_element_add_pad (GST_ELEMENT (src), src->pad); + + gst_auto_video_src_reset (src); + + /* set the default raw video caps */ + src->filter_caps = gst_static_caps_get (&raw_caps); + + /* mark as source */ + GST_OBJECT_FLAG_UNSET (src, GST_ELEMENT_IS_SINK); +} + +static gboolean +gst_auto_video_src_factory_filter (GstPluginFeature * feature, gpointer data) +{ + guint rank; + const gchar *klass; + + /* we only care about element factories */ + if (!GST_IS_ELEMENT_FACTORY (feature)) + return FALSE; + + /* video sources */ + klass = gst_element_factory_get_klass (GST_ELEMENT_FACTORY (feature)); + if (!(strstr (klass, "Source") && strstr (klass, "Video"))) + return FALSE; + + /* only select elements with autoplugging rank */ + rank = gst_plugin_feature_get_rank (feature); + if (rank < GST_RANK_MARGINAL) + return FALSE; + + return TRUE; +} + +static gint +gst_auto_video_src_compare_ranks (GstPluginFeature * f1, GstPluginFeature * f2) +{ + gint diff; + + diff = gst_plugin_feature_get_rank (f2) - gst_plugin_feature_get_rank (f1); + if (diff != 0) + return diff; + return strcmp (gst_plugin_feature_get_name (f2), + gst_plugin_feature_get_name (f1)); +} + +static GstElement * +gst_auto_video_src_create_element_with_pretty_name (GstAutoVideoSrc * src, + GstElementFactory * factory) +{ + GstElement *element; + gchar *name, *marker; + + marker = g_strdup (GST_PLUGIN_FEATURE (factory)->name); + if (g_str_has_suffix (marker, "src")) + marker[strlen (marker) - 4] = '\0'; + if (g_str_has_prefix (marker, "gst")) + g_memmove (marker, marker + 3, strlen (marker + 3) + 1); + name = g_strdup_printf ("%s-actual-src-%s", GST_OBJECT_NAME (src), marker); + g_free (marker); + + element = gst_element_factory_create (factory, name); + g_free (name); + + return element; +} + +static GstElement * +gst_auto_video_src_find_best (GstAutoVideoSrc * src) +{ + 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, *intersect = NULL; + gboolean no_match = TRUE; + + list = gst_registry_feature_filter (gst_registry_get_default (), + (GstPluginFeatureFilter) gst_auto_video_src_factory_filter, FALSE, src); + list = g_list_sort (list, (GCompareFunc) gst_auto_video_src_compare_ranks); + + GST_LOG_OBJECT (src, "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_src_create_element_with_pretty_name (src, f))) { + GstStateChangeReturn ret; + + GST_DEBUG_OBJECT (src, "Testing %s", GST_PLUGIN_FEATURE (f)->name); + + /* If AutoVideoSrc has been provided with filter caps, + * accept only sources that match with the filter caps */ + if (src->filter_caps) { + el_pad = gst_element_get_static_pad (GST_ELEMENT (el), "src"); + el_caps = gst_pad_get_caps (el_pad); + gst_object_unref (el_pad); + GST_DEBUG_OBJECT (src, + "Checking caps: %" GST_PTR_FORMAT " vs. %" GST_PTR_FORMAT, + src->filter_caps, el_caps); + intersect = gst_caps_intersect (src->filter_caps, el_caps); + no_match = gst_caps_is_empty (intersect); + gst_caps_unref (el_caps); + gst_caps_unref (intersect); + + if (no_match) { + GST_DEBUG_OBJECT (src, "Incompatible caps"); + gst_object_unref (el); + continue; + } else { + GST_DEBUG_OBJECT (src, "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 (src, "This worked!"); + choice = el; + break; + } + + /* collect all error messages */ + while ((message = gst_bus_pop_filtered (bus, GST_MESSAGE_ERROR))) { + GST_DEBUG_OBJECT (src, "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 (src, "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 (src, "reposting message %p", errors->data); + gst_element_post_message (GST_ELEMENT (src), GST_MESSAGE (errors->data)); + } else { + /* send warning message to application and use a fakesrc */ + GST_ELEMENT_WARNING (src, RESOURCE, NOT_FOUND, (NULL), + ("Failed to find a usable video source")); + choice = gst_element_factory_make ("fakesrc", "fake-video-src"); + 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; +} + +static gboolean +gst_auto_video_src_detect (GstAutoVideoSrc * src) +{ + GstElement *esrc; + GstPad *targetpad; + + gst_auto_video_src_clear_kid (src); + + /* find element */ + GST_DEBUG_OBJECT (src, "Creating new kid"); + if (!(esrc = gst_auto_video_src_find_best (src))) + goto no_src; + + src->kid = esrc; + gst_bin_add (GST_BIN (src), esrc); + + /* attach ghost pad */ + GST_DEBUG_OBJECT (src, "Re-assigning ghostpad"); + targetpad = gst_element_get_static_pad (src->kid, "src"); + gst_ghost_pad_set_target (GST_GHOST_PAD (src->pad), targetpad); + gst_object_unref (targetpad); + GST_DEBUG_OBJECT (src, "done changing auto video source"); + + return TRUE; + + /* ERRORS */ +no_src: + { + GST_ELEMENT_ERROR (src, LIBRARY, INIT, (NULL), + ("Failed to find a supported video source")); + return FALSE; + } +} + +static GstStateChangeReturn +gst_auto_video_src_change_state (GstElement * element, + GstStateChange transition) +{ + GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS; + GstAutoVideoSrc *src = GST_AUTO_VIDEO_SRC (element); + + switch (transition) { + case GST_STATE_CHANGE_NULL_TO_READY: + if (!gst_auto_video_src_detect (src)) + return GST_STATE_CHANGE_FAILURE; + break; + default: + break; + } + + ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition); + + switch (transition) { + case GST_STATE_CHANGE_READY_TO_NULL: + gst_auto_video_src_reset (src); + break; + default: + break; + } + + return ret; +} + +static void +gst_auto_video_src_set_property (GObject * object, guint prop_id, + const GValue * value, GParamSpec * pspec) +{ + GstAutoVideoSrc *src = GST_AUTO_VIDEO_SRC (object); + + switch (prop_id) { + case PROP_CAPS: + if (src->filter_caps) + gst_caps_unref (src->filter_caps); + src->filter_caps = gst_caps_copy (gst_value_get_caps (value)); + break; + default: + G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); + break; + } +} + +static void +gst_auto_video_src_get_property (GObject * object, guint prop_id, + GValue * value, GParamSpec * pspec) +{ + GstAutoVideoSrc *src = GST_AUTO_VIDEO_SRC (object); + + switch (prop_id) { + case PROP_CAPS:{ + gst_value_set_caps (value, src->filter_caps); + break; + } + default: + G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); + break; + } +} |