2 * (c) 2005 Ronald S. Bultje <rbultje@ronald.bitfreak.net>
3 * (c) 2006 Jan Schmidt <thaytan@noraisin.net>
4 * (c) 2008 Stefan Kost <ensonic@users.sf.net>
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Library General Public License for more details.
16 * You should have received a copy of the GNU Library General Public
17 * License along with this library; if not, write to the
18 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 * Boston, MA 02111-1307, USA.
23 * SECTION:element-autovideosrc
24 * @see_also: autoaudiosrc, v4l2src, v4lsrc
26 * autovideosrc is a video src that automatically detects an appropriate
27 * video source to use. It does so by scanning the registry for all elements
28 * that have <quote>Source</quote> and <quote>Video</quote> in the class field
29 * of their element information, and also have a non-zero autoplugging rank.
32 * <title>Example launch line</title>
34 * gst-launch -v -m autovideosrc ! xvimagesink
45 #include "gstautovideosrc.h"
46 #include "gstautodetect.h"
55 static GstStateChangeReturn
56 gst_auto_video_src_change_state (GstElement * element,
57 GstStateChange transition);
58 static void gst_auto_video_src_dispose (GstAutoVideoSrc * src);
59 static void gst_auto_video_src_clear_kid (GstAutoVideoSrc * src);
61 static void gst_auto_video_src_set_property (GObject * object, guint prop_id,
62 const GValue * value, GParamSpec * pspec);
63 static void gst_auto_video_src_get_property (GObject * object, guint prop_id,
64 GValue * value, GParamSpec * pspec);
66 GST_BOILERPLATE (GstAutoVideoSrc, gst_auto_video_src, GstBin, GST_TYPE_BIN);
68 static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
74 gst_auto_video_src_base_init (gpointer klass)
76 GstElementClass *eklass = GST_ELEMENT_CLASS (klass);
78 gst_element_class_add_static_pad_template (eklass, &src_template);
79 gst_element_class_set_details_simple (eklass, "Auto video source",
81 "Wrapper video source for automatically detected video source",
82 "Jan Schmidt <thaytan@noraisin.net>, "
83 "Stefan Kost <ensonic@users.sf.net>");
87 gst_auto_video_src_class_init (GstAutoVideoSrcClass * klass)
89 GObjectClass *gobject_class;
90 GstElementClass *eklass = GST_ELEMENT_CLASS (klass);
92 gobject_class = G_OBJECT_CLASS (klass);
93 gobject_class->dispose = (GObjectFinalizeFunc) gst_auto_video_src_dispose;
94 gobject_class->set_property = gst_auto_video_src_set_property;
95 gobject_class->get_property = gst_auto_video_src_get_property;
97 eklass->change_state = GST_DEBUG_FUNCPTR (gst_auto_video_src_change_state);
100 * GstAutoVideoSrc:filter-caps
102 * This property will filter out candidate sources that can handle the specified
103 * caps. By default only video sources that support raw rgb and yuv video
106 * This property can only be set before the element goes to the READY state.
110 g_object_class_install_property (gobject_class, PROP_CAPS,
111 g_param_spec_boxed ("filter-caps", "Filter caps",
112 "Filter src candidates using these caps.", GST_TYPE_CAPS,
113 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
117 gst_auto_video_src_dispose (GstAutoVideoSrc * src)
119 gst_auto_video_src_clear_kid (src);
121 if (src->filter_caps)
122 gst_caps_unref (src->filter_caps);
123 src->filter_caps = NULL;
125 G_OBJECT_CLASS (parent_class)->dispose ((GObject *) src);
129 gst_auto_video_src_clear_kid (GstAutoVideoSrc * src)
132 gst_element_set_state (src->kid, GST_STATE_NULL);
133 gst_bin_remove (GST_BIN (src), src->kid);
135 /* Don't loose SOURCE flag */
136 GST_OBJECT_FLAG_SET (src, GST_ELEMENT_IS_SOURCE);
141 * Hack to make initial linking work; ideally, this'd work even when
142 * no target has been assigned to the ghostpad yet.
146 gst_auto_video_src_reset (GstAutoVideoSrc * src)
150 /* Remove any existing element */
151 gst_auto_video_src_clear_kid (src);
153 /* fakesrc placeholder */
154 src->kid = gst_element_factory_make ("fakesrc", "tempsrc");
155 gst_bin_add (GST_BIN (src), src->kid);
158 targetpad = gst_element_get_static_pad (src->kid, "src");
159 gst_ghost_pad_set_target (GST_GHOST_PAD (src->pad), targetpad);
160 gst_object_unref (targetpad);
163 static GstStaticCaps raw_caps =
164 GST_STATIC_CAPS ("video/x-raw-yuv; video/x-raw-rgb");
167 gst_auto_video_src_init (GstAutoVideoSrc * src, GstAutoVideoSrcClass * g_class)
169 src->pad = gst_ghost_pad_new_no_target ("src", GST_PAD_SRC);
170 gst_element_add_pad (GST_ELEMENT (src), src->pad);
172 gst_auto_video_src_reset (src);
174 /* set the default raw video caps */
175 src->filter_caps = gst_static_caps_get (&raw_caps);
178 GST_OBJECT_FLAG_SET (src, GST_ELEMENT_IS_SOURCE);
182 gst_auto_video_src_factory_filter (GstPluginFeature * feature, gpointer data)
187 /* we only care about element factories */
188 if (!GST_IS_ELEMENT_FACTORY (feature))
192 klass = gst_element_factory_get_klass (GST_ELEMENT_FACTORY (feature));
193 if (!(strstr (klass, "Source") && strstr (klass, "Video")))
196 /* only select elements with autoplugging rank */
197 rank = gst_plugin_feature_get_rank (feature);
198 if (rank < GST_RANK_MARGINAL)
205 gst_auto_video_src_compare_ranks (GstPluginFeature * f1, GstPluginFeature * f2)
209 diff = gst_plugin_feature_get_rank (f2) - gst_plugin_feature_get_rank (f1);
212 return strcmp (gst_plugin_feature_get_name (f2),
213 gst_plugin_feature_get_name (f1));
217 gst_auto_video_src_create_element_with_pretty_name (GstAutoVideoSrc * src,
218 GstElementFactory * factory)
221 gchar *name, *marker;
223 marker = g_strdup (GST_PLUGIN_FEATURE (factory)->name);
224 if (g_str_has_suffix (marker, "src"))
225 marker[strlen (marker) - 4] = '\0';
226 if (g_str_has_prefix (marker, "gst"))
227 g_memmove (marker, marker + 3, strlen (marker + 3) + 1);
228 name = g_strdup_printf ("%s-actual-src-%s", GST_OBJECT_NAME (src), marker);
231 element = gst_element_factory_create (factory, name);
238 gst_auto_video_src_find_best (GstAutoVideoSrc * src)
241 GstElement *choice = NULL;
242 GstMessage *message = NULL;
243 GSList *errors = NULL;
244 GstBus *bus = gst_bus_new ();
245 GstPad *el_pad = NULL;
246 GstCaps *el_caps = NULL;
247 gboolean no_match = TRUE;
249 list = gst_registry_feature_filter (gst_registry_get_default (),
250 (GstPluginFeatureFilter) gst_auto_video_src_factory_filter, FALSE, src);
251 list = g_list_sort (list, (GCompareFunc) gst_auto_video_src_compare_ranks);
253 GST_LOG_OBJECT (src, "Trying to find usable video devices ...");
255 for (item = list; item != NULL; item = item->next) {
256 GstElementFactory *f = GST_ELEMENT_FACTORY (item->data);
259 if ((el = gst_auto_video_src_create_element_with_pretty_name (src, f))) {
260 GstStateChangeReturn ret;
262 GST_DEBUG_OBJECT (src, "Testing %s", GST_PLUGIN_FEATURE (f)->name);
264 /* If AutoVideoSrc has been provided with filter caps,
265 * accept only sources that match with the filter caps */
266 if (src->filter_caps) {
267 el_pad = gst_element_get_static_pad (GST_ELEMENT (el), "src");
268 el_caps = gst_pad_get_caps (el_pad);
269 gst_object_unref (el_pad);
270 GST_DEBUG_OBJECT (src,
271 "Checking caps: %" GST_PTR_FORMAT " vs. %" GST_PTR_FORMAT,
272 src->filter_caps, el_caps);
273 no_match = !gst_caps_can_intersect (src->filter_caps, el_caps);
274 gst_caps_unref (el_caps);
277 GST_DEBUG_OBJECT (src, "Incompatible caps");
278 gst_object_unref (el);
281 GST_DEBUG_OBJECT (src, "Found compatible caps");
285 gst_element_set_bus (el, bus);
286 ret = gst_element_set_state (el, GST_STATE_READY);
287 if (ret == GST_STATE_CHANGE_SUCCESS) {
288 GST_DEBUG_OBJECT (src, "This worked!");
293 /* collect all error messages */
294 while ((message = gst_bus_pop_filtered (bus, GST_MESSAGE_ERROR))) {
295 GST_DEBUG_OBJECT (src, "error message %" GST_PTR_FORMAT, message);
296 errors = g_slist_append (errors, message);
299 gst_element_set_state (el, GST_STATE_NULL);
300 gst_object_unref (el);
304 GST_DEBUG_OBJECT (src, "done trying");
307 /* FIXME: we forward the first error for now; but later on it might make
308 * sense to actually analyse them */
309 gst_message_ref (GST_MESSAGE (errors->data));
310 GST_DEBUG_OBJECT (src, "reposting message %p", errors->data);
311 gst_element_post_message (GST_ELEMENT (src), GST_MESSAGE (errors->data));
313 /* send warning message to application and use a fakesrc */
314 GST_ELEMENT_WARNING (src, RESOURCE, NOT_FOUND, (NULL),
315 ("Failed to find a usable video source"));
316 choice = gst_element_factory_make ("fakesrc", "fake-video-src");
317 if (g_object_class_find_property (G_OBJECT_GET_CLASS (choice), "sync"))
318 g_object_set (choice, "sync", TRUE, NULL);
319 gst_element_set_state (choice, GST_STATE_READY);
322 gst_object_unref (bus);
323 gst_plugin_feature_list_free (list);
324 g_slist_foreach (errors, (GFunc) gst_mini_object_unref, NULL);
325 g_slist_free (errors);
331 gst_auto_video_src_detect (GstAutoVideoSrc * src)
336 gst_auto_video_src_clear_kid (src);
339 GST_DEBUG_OBJECT (src, "Creating new kid");
340 if (!(esrc = gst_auto_video_src_find_best (src)))
344 gst_bin_add (GST_BIN (src), esrc);
346 /* attach ghost pad */
347 GST_DEBUG_OBJECT (src, "Re-assigning ghostpad");
348 targetpad = gst_element_get_static_pad (src->kid, "src");
349 if (!gst_ghost_pad_set_target (GST_GHOST_PAD (src->pad), targetpad))
352 gst_object_unref (targetpad);
353 GST_DEBUG_OBJECT (src, "done changing auto video source");
360 GST_ELEMENT_ERROR (src, LIBRARY, INIT, (NULL),
361 ("Failed to find a supported video source"));
366 GST_ELEMENT_ERROR (src, LIBRARY, INIT, (NULL),
367 ("Failed to set target pad"));
368 gst_object_unref (targetpad);
373 static GstStateChangeReturn
374 gst_auto_video_src_change_state (GstElement * element,
375 GstStateChange transition)
377 GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
378 GstAutoVideoSrc *src = GST_AUTO_VIDEO_SRC (element);
380 switch (transition) {
381 case GST_STATE_CHANGE_NULL_TO_READY:
382 if (!gst_auto_video_src_detect (src))
383 return GST_STATE_CHANGE_FAILURE;
389 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
391 switch (transition) {
392 case GST_STATE_CHANGE_READY_TO_NULL:
393 gst_auto_video_src_reset (src);
403 gst_auto_video_src_set_property (GObject * object, guint prop_id,
404 const GValue * value, GParamSpec * pspec)
406 GstAutoVideoSrc *src = GST_AUTO_VIDEO_SRC (object);
410 if (src->filter_caps)
411 gst_caps_unref (src->filter_caps);
412 src->filter_caps = gst_caps_copy (gst_value_get_caps (value));
415 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
421 gst_auto_video_src_get_property (GObject * object, guint prop_id,
422 GValue * value, GParamSpec * pspec)
424 GstAutoVideoSrc *src = GST_AUTO_VIDEO_SRC (object);
428 gst_value_set_caps (value, src->filter_caps);
432 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);