Function

CMMetadataFormatDescriptionCreateWithKeys

Creates a metadata format description object specified by the key.

Declaration

OSStatus CMMetadataFormatDescriptionCreateWithKeys(CFAllocatorRef allocator, CMMetadataFormatType metadataType, CFArrayRef keys, CMMetadataFormatDescriptionRef  _Nullable *formatDescriptionOut);

Parameters

allocator

CFAllocator to be used. Pass NULL or kCFAllocatorDefault to use the default allocator.

metadataType

The type of metadata (kCMMetadataFormatType_Boxed).

keys

Array of metadata keys. Each key is a dictionary of key properties. The required properties are:

  • kCMMetadataFormatDescriptionKey_Namespace

  • kCMMetadataFormatDescriptionKey_Value

  • kCMMetadataFormatDescriptionKey_LocalID

outDesc

Returns newly created metadata CMFormatDescription.

Return Value

A result code. Returns noErr if successful.

See Also

Metadata-Specific Functions

CMMetadataFormatDescriptionGetKeyWithLocalID

Returns the key associated with the metadata for the given local id.

CMMetadataFormatDescriptionCopyAsBigEndianMetadataDescriptionBlockBuffer

Copies the contents of a CMMetadataFormatDescription to a CMBlockBuffer in big-endian byte ordering.

CMMetadataFormatDescriptionCreateFromBigEndianMetadataDescriptionBlockBuffer

Creates a CMMetadataFormatDescription from a big-endian MetadataDescription data structure in a CMBlockBuffer.

CMMetadataFormatDescriptionCreateFromBigEndianMetadataDescriptionData

Creates a CMMetadataFormatDescription from a big-endian MetadataDescription data structure.

CMMetadataFormatDescriptionCreateWithMetadataSpecifications

Creates a new CMMetadataFormatDescription.

CMSwapBigEndianMetadataDescriptionToHost

Converts a MetadataDescription data structure from big-endian to host-endian in place.

CMSwapHostEndianMetadataDescriptionToBig

Converts a MetadataDescription data structure from host-endian to big-endian in place.

CMMetadataFormatDescriptionGetIdentifiers

Gets an array of metadata identifiers from a metadata format description.