Meta

The #GstMeta structure should be included as the first member of a #GstBuffer metadata structure. The structure defines the API of the metadata and should be accessible to all elements using the metadata.

A metadata API is registered with gst_meta_api_type_register() which takes a name for the metadata API and some tags associated with the metadata. With gst_meta_api_type_has_tag() one can check if a certain metadata API contains a given tag.

Multiple implementations of a metadata API can be registered. To implement a metadata API, gst_meta_register() should be used. This function takes all parameters needed to create, free and transform metadata along with the size of the metadata. The function returns a #GstMetaInfo structure that contains the information for the implementation of the API.

A specific implementation can be retrieved by name with gst_meta_get_info().

See #GstBuffer for how the metadata can be added, retrieved and removed from buffers.

struct Meta {

static string[] apiTypeGetTags(GType api);

static bool apiTypeHasTag(GType api, GQuark tag);

static GType apiTypeRegister(string api, string[] tags);

static GstMetaInfo* getInfo(string impl);

static GstMetaInfo* register(GType api, string impl, size_t size, GstMetaInitFunction initFunc, GstMetaFreeFunction freeFunc, GstMetaTransformFunction transformFunc);

}

Members

Static functions

apiTypeGetTags string[] apiTypeGetTags(GType api)
apiTypeHasTag bool apiTypeHasTag(GType api, GQuark tag): Check if @api was registered with @tag.
apiTypeRegister GType apiTypeRegister(string api, string[] tags): Register and return a GType for the @api and associate it with @tags.
getInfo GstMetaInfo* getInfo(string impl): Lookup a previously registered meta info structure by its implementation name @impl.
register GstMetaInfo* register(GType api, string impl, size_t size, GstMetaInitFunction initFunc, GstMetaFreeFunction freeFunc, GstMetaTransformFunction transformFunc): Register a new #GstMeta implementation.

Meta

Members

Static functions

Meta

Source