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.Meta.apiTypeRegister which takes a name for the metadata API and some tags associated with the metadata. With gst.meta.Meta.apiTypeHasTag 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.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.Meta.getInfo.

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

class Meta {

GstMeta cInstance;

int compareSeqnum(gst.meta.Meta meta2);

ulong getSeqnum();

bool serializeSimple(ubyte[] data);

static string[] apiTypeGetTags(gobject.types.GType api);

static bool apiTypeHasTag(gobject.types.GType api, glib.types.Quark tag);

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

static gst.meta.Meta deserialize(gst.buffer.Buffer buffer, ubyte[] data, uint consumed);

static gst.meta_info.MetaInfo getInfo(string impl);

static gst.meta_info.MetaInfo registerCustom(string name, string[] tags, gst.types.CustomMetaTransformFunction transformFunc);

static gst.meta_info.MetaInfo registerCustomSimple(string name);

}

Members

Functions

compareSeqnum int compareSeqnum(gst.meta.Meta meta2): Meta sequence number compare function. Can be used as #GCompareFunc or a #GCompareDataFunc.
getSeqnum ulong getSeqnum(): Gets seqnum for this meta.
serializeSimple bool serializeSimple(ubyte[] data): Same as gst.meta.Meta.serialize but with a #GByteArray instead of #GstByteArrayInterface.

Static functions

apiTypeGetTags string[] apiTypeGetTags(gobject.types.GType api)
apiTypeHasTag bool apiTypeHasTag(gobject.types.GType api, glib.types.Quark tag): Check if api was registered with tag.
apiTypeRegister gobject.types.GType apiTypeRegister(string api, string[] tags): Register and return a GType for the api and associate it with tags.
deserialize gst.meta.Meta deserialize(gst.buffer.Buffer buffer, ubyte[] data, uint consumed): Recreate a #GstMeta from serialized data returned by gst.meta.Meta.serialize and add it to buffer.
getInfo gst.meta_info.MetaInfo getInfo(string impl): Lookup a previously registered meta info structure by its implementation name impl.
registerCustom gst.meta_info.MetaInfo registerCustom(string name, string[] tags, gst.types.CustomMetaTransformFunction transformFunc): Register a new custom #GstMeta implementation, backed by an opaque structure holding a #GstStructure.
registerCustomSimple gst.meta_info.MetaInfo registerCustomSimple(string name): Simplified version of gst.meta.Meta.registerCustom, with no tags and no transform function.

gst meta classes

Meta