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# AudioTimeStamp

A structure that represents a timestamp value.

```
struct AudioTimeStamp
```

## Topics

### Accessing the Data

[`mFlags`](/documentation/CoreAudioTypes/AudioTimeStamp/mFlags)

A set of flags indicating which representations of the time are valid; see `Audio Time Stamp Flags` and `Audio Time Stamp Flag Combination Constant`.

[`mHostTime`](/documentation/CoreAudioTypes/AudioTimeStamp/mHostTime)

The host machine’s time base (see `CoreAudio/HostTime.h`).

[`mRateScalar`](/documentation/CoreAudioTypes/AudioTimeStamp/mRateScalar)

The ratio of actual host ticks per sample frame to the nominal host ticks per sample frame.

[`mReserved`](/documentation/CoreAudioTypes/AudioTimeStamp/mReserved)

Pads the structure out to force an even 8-byte alignment.

[`mSMPTETime`](/documentation/CoreAudioTypes/AudioTimeStamp/mSMPTETime)

The SMPTE time (see [`SMPTETime`](/documentation/CoreAudioTypes/SMPTETime)).

[`mSampleTime`](/documentation/CoreAudioTypes/AudioTimeStamp/mSampleTime)

The absolute sample frame time.

[`mWordClockTime`](/documentation/CoreAudioTypes/AudioTimeStamp/mWordClockTime)

The word clock time.

### Initializers

[`init()`](/documentation/CoreAudioTypes/AudioTimeStamp/init())

Creates an empty audio timestamp.

[`init(mSampleTime:mHostTime:mRateScalar:mWordClockTime:mSMPTETime:mFlags:mReserved:)`](/documentation/CoreAudioTypes/AudioTimeStamp/init(mSampleTime:mHostTime:mRateScalar:mWordClockTime:mSMPTETime:mFlags:mReserved:))

Creates an audio time stamp.

## Relationships

### Conforms To

[`BitwiseCopyable`](/documentation/Swift/BitwiseCopyable)

[`Sendable`](/documentation/Swift/Sendable)

---

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