| Top |  |
 |
 |
 |
Functions
| GList * | gst_type_find_factory_get_list () |
| const gchar * const * | gst_type_find_factory_get_extensions () |
| GstCaps * | gst_type_find_factory_get_caps () |
| gboolean | gst_type_find_factory_has_function () |
| void | gst_type_find_factory_call_function () |
Object Hierarchy
GObject ╰── GInitiallyUnowned ╰── GstObject ╰── GstPluginFeature ╰── GstTypeFindFactory
Description
These functions allow querying informations about registered typefind
functions. How to create and register these functions is described in
the section
Example 13. how to write a simple typefinder
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 |
typedef struct { guint8 *data; guint size; guint probability; GstCaps *data; } MyTypeFind; static void my_peek (gpointer data, gint64 offset, guint size) { MyTypeFind *find = (MyTypeFind *) data; if (offset >= 0 && offset + size <= find->size) { return find->data + offset; } return NULL; } static void my_suggest (gpointer data, guint probability, GstCaps *caps) { MyTypeFind *find = (MyTypeFind *) data; if (probability > find->probability) { find->probability = probability; gst_caps_replace (&find->caps, caps); } } static GstCaps * find_type (guint8 *data, guint size) { GList *walk, *type_list; MyTypeFind find = {data, size, 0, NULL}; GstTypeFind gst_find = {my_peek, my_suggest, &find, }; walk = type_list = gst_type_find_factory_get_list (); while (walk) { GstTypeFindFactory *factory = GST_TYPE_FIND_FACTORY (walk->data); walk = g_list_next (walk) gst_type_find_factory_call_function (factory, &gst_find); } g_list_free (type_list); return find.caps; }; |
The above example shows how to write a very simple typefinder that identifies the given data. You can get quite a bit more complicated than that though.
Last reviewed on 2005-11-09 (0.9.4)
Functions
gst_type_find_factory_get_list ()
GList *
gst_type_find_factory_get_list (void);
Gets the list of all registered typefind factories. You must free the
list using gst_plugin_feature_list_free().
The returned factories are sorted by highest rank first, and then by factory name.
Free-function: gst_plugin_feature_list_free
Returns
the list of all registered GstTypeFindFactory.
[transfer full][element-type Gst.TypeFindFactory]
gst_type_find_factory_get_extensions ()
const gchar * const *
gst_type_find_factory_get_extensions (GstTypeFindFactory *factory);
Gets the extensions associated with a GstTypeFindFactory. The returned
array should not be changed. If you need to change stuff in it, you should
copy it using g_strdupv(). This function may return NULL to indicate
a 0-length list.
gst_type_find_factory_get_caps ()
GstCaps *
gst_type_find_factory_get_caps (GstTypeFindFactory *factory);
Gets the GstCaps associated with a typefind factory.
gst_type_find_factory_has_function ()
gboolean
gst_type_find_factory_has_function (GstTypeFindFactory *factory);
Check whether the factory has a typefind function. Typefind factories without typefind functions are a last-effort fallback mechanism to e.g. assume a certain media type based on the file extension.
gst_type_find_factory_call_function ()
void gst_type_find_factory_call_function (GstTypeFindFactory *factory,GstTypeFind *find);
Calls the GstTypeFindFunction associated with this factory.
Parameters
factory |
||
find |
a properly setup GstTypeFind entry. The get_data and suggest_type members must be set. |
[transfer none] |