Meta

Object Hierarchy:

Description:

[ CCode ( has_type_id = false ) ]
public struct Meta

The Meta structure should be included as the first member of a Buffer 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 api_type_register which takes a name for the metadata API and some tags associated with the metadata. With 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, 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 MetaInfo structure that contains the information for the implementation of the API.

A specific implementation can be retrieved by name with get_info.

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

Namespace: Gst

Package: gstreamer-1.0

Content:

Static methods:

public static unowned string[] api_type_get_tags (Type api)
public static bool api_type_has_tag (Type api, Quark tag)
Check if api was registered with tag.
public static Type api_type_register (string api, string[] tags)
Register and return a GType for the api and associate it with tags.
public static unowned MetaInfo? get_info (string impl)
Lookup a previously registered meta info structure by its implementation name impl.
public static unowned MetaInfo? register (Type api, string impl, size_t size, MetaInitFunction init_func, MetaFreeFunction free_func, MetaTransformFunction transform_func)
Register a new Meta implementation.
public static unowned MetaInfo? register_custom (string name, string[] tags, owned CustomMetaTransformFunction? transform_func)
Register a new custom Meta implementation, backed by an opaque structure holding a Structure.

Methods:

public int compare_seqnum (Meta meta2)
Meta sequence number compare function.
public uint64 get_seqnum ()
Gets seqnum for this meta.

Fields:

public MetaFlags flags
public unowned MetaInfo? info