Instance Property

extraAttributes

The additional attributes supplied by the metadata item.

Declaration

@property(nonatomic, readonly, copy) NSDictionary<AVMetadataExtraAttributeKey, id> *extraAttributes;

Discussion

Extra attributes, when they are present, are specific to metadata container formats and keys in their associated key-spaces. For example, the "attached picture" frame defined by the ID3 tag specification can be represented by an AVMetadataItem with keyspace AVMetadataKeySpaceID3, key AVMetadataID3MetadataKeyAttachedPicture, a value that carries the image data, and extra attributes that include a description of the picture as carried in the 'APIC' frame of the ID3 tag.

See Also

Accessing Metadata Values

value

The value of the metadata item.

time

The timestamp of the metadata item.

duration

The duration of the metadata item.

locale

The locale of the metadata item.

dataValue

The raw bytes of the value for the metadata item.

AVMetadataExtraAttributeKey

A value that defines extra attribute keys.

dataType

The data type of the metadata item's value.

extendedLanguageTag

The IETF BCP 47 (RFC 4646) language identifier of the metadata item.

startDate

The start date of the timed metadata.

+ identifierForKey:keySpace:

Provides the metadata identifier that’s equivalent to a key and key space.

AVMetadataKeySpace

A value that defines a metadata key space.

identifier

The identifier of the metadata item.

+ keyForIdentifier:

Returns the metadata key associated with the identifier.

+ keySpaceForIdentifier:

Returns the metadata key space associated with the identifier.

AVMetadataIdentifier

A value that defines the metadata identifiers for different file formats.