TypeFindFactory

These functions allow querying information 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.

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;
};

class TypeFindFactory : PluginFeature {

static gst.type_find_factory.TypeFindFactory[] getList();

void callFunction(gst.type_find.TypeFind find);

gst.caps.Caps getCaps();

string[] getExtensions();

bool hasFunction();

}

Members

Functions

callFunction void callFunction(gst.type_find.TypeFind find): Calls the #GstTypeFindFunction associated with this factory.
getCaps gst.caps.Caps getCaps(): Gets the #GstCaps associated with a typefind factory.
getExtensions string[] getExtensions(): 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 glib.global.strdupv. This function may return null to indicate a 0-length list.
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 gst.type_find_factory.TypeFindFactory[] getList(): Gets the list of all registered typefind factories. You must free the list using gst.plugin_feature.PluginFeature.listFree.

Inherited Members

From PluginFeature

listCopy gst.plugin_feature.PluginFeature[] listCopy(gst.plugin_feature.PluginFeature[] list): Copies the list of features. Caller should call gst_plugin_feature_list_free when done with the list.
listDebug void listDebug(gst.plugin_feature.PluginFeature[] list): Debug the plugin feature names in list.
rankCompareFunc int rankCompareFunc(const(void)* p1, const(void)* p2): Compares the two given #GstPluginFeature 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 gst.plugin.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 gst.plugin_feature.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.

gst type_find_factory classes

TypeFindFactory