Struct gstreamer::TypeFindFactory

pub struct TypeFindFactory(_, _);

These functions allow querying information about registered typefind functions. How to create and register these functions is described in the section "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;
  };

Implements

PluginFeatureExt, GstObjectExt, glib::object::ObjectExt, PluginFeatureExtManual

Implementations

impl TypeFindFactory

pub fn get_caps(&self) -> Option<Caps>

Gets the Caps associated with a typefind factory.

Returns

the Caps associated with this factory

pub fn get_extensions(&self) -> Vec<GString>

Gets the extensions associated with a 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 None to indicate a 0-length list.

Returns

a None-terminated array of extensions associated with this factory

pub fn has_function(&self) -> bool

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.

Returns

true if the factory has a typefind functions set, otherwise false

pub fn get_list() -> Vec<TypeFindFactory>

Gets the list of all registered typefind factories. You must free the list using PluginFeature::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 TypeFindFactory.

impl TypeFindFactory

pub fn call_function(&self, find: &mut dyn TypeFindImpl)

Calls the GstTypeFindFunction associated with this factory.

find

a properly setup TypeFind entry. The get_data and suggest_type members must be set.

Trait Implementations

impl Clone for TypeFindFactory

fn clone(&self) -> TypeFindFactory

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for TypeFindFactory

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for TypeFindFactory

impl Hash for TypeFindFactory

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl IsA<Object> for TypeFindFactory

impl IsA<PluginFeature> for TypeFindFactory

impl Ord for TypeFindFactory

fn cmp(&self, other: &TypeFindFactory) -> Ordering

This method returns an Ordering between self and other.

#[must_use]fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]fn clamp(self, min: Self, max: Self) -> Self

🔬 This is a nightly-only experimental API. (clamp)

Restrict a value to a certain interval.

impl<T: ObjectType> PartialEq<T> for TypeFindFactory

fn eq(&self, other: &T) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use]fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<T: ObjectType> PartialOrd<T> for TypeFindFactory

fn partial_cmp(&self, other: &T) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

#[must_use]fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

#[must_use]fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

#[must_use]fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

#[must_use]fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Send for TypeFindFactory

impl StaticType for TypeFindFactory

fn static_type() -> Type

Returns the type identifier of Self.

impl Sync for TypeFindFactory