AVAssetReaderOutputMetadataAdaptorMBS.Constructor(trackOutput as AVAssetReaderTrackOutputMBS)

Type	Topic	Plugin	Version	macOS	Windows	Linux	iOS	Targets
method	AVFoundation	MBS AVFoundation Plugin	14.4	✅ Yes	❌ No	❌ No	✅ Yes	All

Creates a new timed metadata group adaptor for retrieving timed metadata group objects from an asset reader output.

assetReaderOutput: An instance of AVAssetReaderTrackOutput that vends sample buffers containing metadata, e.g. an AVAssetReaderTrackOutput object initialized with a track of media type AVMediaTypeMetadata and nil outputSettings.

Returns an instance of AVAssetReaderTrackOutputTimedMetadataGroupAdaptor

It is an error to create a timed metadata group adaptor with an asset reader output that does not vend metadata. It is also an error to create a timed metadata group adaptor with an asset reader output whose asset reader has already started reading, or an asset reader output that already has been used to initialize another timed metadata group adaptor.

Clients should not mix calls to AVAssetReaderTrackOutput.NextSampleBuffer and AVAssetReaderOutputMetadataAdaptor.nextTimedMetadataGroup. Once an AVAssetReaderTrackOutput instance has been used to initialize an AVAssetReaderOutputMetadataAdaptor, calling NextSampleBuffer on that instance will result in an exception being thrown.

AVAssetReaderOutputMetadataAdaptorMBS.nextTimedMetadataGroup as AVTimedMetadataGroupMBS

Type	Topic	Plugin	Version	macOS	Windows	Linux	iOS	Targets
method	AVFoundation	MBS AVFoundation Plugin	14.4	✅ Yes	❌ No	❌ No	✅ Yes	All

Returns the next timed metadata group for the asset reader output, synchronously.

Returns an instance of AVTimedMetadataGroup, representing the next logical segment of metadata coming from the source asset reader output.

This method will return nil when all timed metadata groups have been read from the asset reader output, or if there is an error that prevents the timed metadata group adaptor from reading more timed metadata groups. When this method returns nil, clients should check the value of the associated AVAssetReader's status property to determine why no more samples could be read.

Before calling this method, you must ensure that the output which underlies the receiver is attached to an AVAssetReader via a prior call to addOutput and that startReading has been called on the asset reader.