---
title: "CMTimebaseCreateWithSourceTimebase(allocator:sourceTimebase:timebaseOut:)"
framework: coremedia
role: symbol
role_heading: Function
path: "coremedia/cmtimebasecreatewithsourcetimebase(allocator:sourcetimebase:timebaseout:)"
---

# CMTimebaseCreateWithSourceTimebase(allocator:sourceTimebase:timebaseOut:)

Creates a timebase by using a source timebase.

## Declaration

```swift
func CMTimebaseCreateWithSourceTimebase(allocator: CFAllocator?, sourceTimebase: CMTimebase, timebaseOut: UnsafeMutablePointer<CMTimebase?>) -> OSStatus
```

## Parameters

- `allocator`: The allocator to use for creating the timebase.
- `sourceTimebase`: The source timebase.
- `timebaseOut`: Receives the timebase the function creates.

## See Also

### Creating Timebases

- [CMTimebaseCreateWithSourceClock(allocator:sourceClock:timebaseOut:)](coremedia/cmtimebasecreatewithsourceclock(allocator:sourceclock:timebaseout:).md)