---
title: nextPreferredStartTimePattern()
framework: Core Media
role: symbol
role_heading: Instance Method
platforms: [iOS 27.0+, iPadOS 27.0+, Mac Catalyst 27.0+, macOS 27.0+, tvOS 27.0+, visionOS 27.0+, watchOS 27.0+]
path: coremedia/cmclock/nextpreferredstarttimepattern()
---

# nextPreferredStartTimePattern()

Returns the pattern of preferred start times, such as for synchronization with an external genlock signal.

## Declaration

```swift
func nextPreferredStartTimePattern() -> CMClock.StartTimePattern?
```

## Discussion

Discussion When a genlock signal is present and disciplined, this function returns a matched time pair in the near future and the delta between successive times.