TypeFindFactory

These functions allow querying informations about registered typefind functions. How to create and register these functions is described in the section <link linkend="gstreamer-Writing-typefind-functions"> "Writing typefind functions"</link>.

The following 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.

1 
2 typedef struct {
3 guint8 *data;
4 guint size;
5 guint probability;
6 GstCaps *data;
7 } MyTypeFind;
8 static void
9 my_peek (gpointer data, gint64 offset, guint size)
10 {
11 MyTypeFind *find = (MyTypeFind *) data;
12 if (offset &gt;= 0 &amp;&amp; offset + size &lt;= find->size) {
13 return find->data + offset;
14 }
15 return NULL;
16 }
17 static void
18 my_suggest (gpointer data, guint probability, GstCaps *caps)
19 {
20 MyTypeFind *find = (MyTypeFind *) data;
21 if (probability &gt; find->probability) {
22 find->probability = probability;
23 gst_caps_replace (&amp;find->caps, caps);
24 }
25 }
26 static GstCaps *
27 find_type (guint8 *data, guint size)
28 {
29 GList *walk, *type_list;
30 MyTypeFind find = {data, size, 0, NULL};
31 GstTypeFind gst_find = {my_peek, my_suggest, &amp;find, };
32 walk = type_list = gst_type_find_factory_get_list ();
33 while (walk) {
34 GstTypeFindFactory *factory = GST_TYPE_FIND_FACTORY (walk->data);
35 walk = g_list_next (walk)
36 gst_type_find_factory_call_function (factory, &amp;gst_find);
37 }
38 g_list_free (type_list);
39 return find.caps;
40 };

Constructors

this
this(GstTypeFindFactory* gstTypeFindFactory, bool ownedRef = false)

Sets our main struct and passes it to the parent class.

Members

Functions

callFunction
void callFunction(TypeFind find)

Calls the GstTypeFindFunction associated with this factory.

getCaps
Caps getCaps()

Gets the gstreamer.Caps associated with a typefind factory.

getExtensions
string[] getExtensions()

Gets the extensions associated with a gstreamer.TypeFindFactory 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.

getStruct
void* getStruct()

the main Gtk struct as a void*

getTypeFindFactoryStruct
GstTypeFindFactory* getTypeFindFactoryStruct(bool transferOwnership = false)

Get the main Gtk struct

hasFunction
bool hasFunction()

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.

Static functions

getList
ListG getList()

Gets the list of all registered typefind factories. You must free the list using Plugin.featureListFree.

getType
GType getType()

Variables

gstTypeFindFactory
GstTypeFindFactory* gstTypeFindFactory;

the main Gtk struct

Inherited Members

From PluginFeature

gstPluginFeature
GstPluginFeature* gstPluginFeature;

the main Gtk struct

getPluginFeatureStruct
GstPluginFeature* getPluginFeatureStruct(bool transferOwnership = false)

Get the main Gtk struct

getStruct
void* getStruct()

the main Gtk struct as a void*

getType
GType getType()
listCopy
ListG listCopy(ListG list)

Copies the list of features. Caller should call gst_plugin_feature_list_free when done with the list.

listDebug
void listDebug(ListG list)

Debug the plugin feature names in list.

listFree
void listFree(ListG list)

Unrefs each member of list, then frees the list.

rankCompareFunc
int rankCompareFunc(void* p1, void* p2)

Compares the two given gstreamer.PluginFeature instances. This function can be used as a GCompareFunc when sorting by rank and then by name.

checkVersion
bool checkVersion(uint minMajor, uint minMinor, uint minMicro)

Checks whether the given plugin feature is at least the required version

getPlugin
Plugin getPlugin()

Get the plugin that provides this feature.

getPluginName
string getPluginName()

Get the name of the plugin that provides this feature.

getRank
uint getRank()

Gets the rank of a plugin feature.

load
PluginFeature load()

Loads the plugin containing feature if it's not already loaded. feature is unaffected; use the return value instead.

setRank
void setRank(uint rank)

Specifies a rank for a plugin feature, so that autoplugging uses the most appropriate feature.

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