---
title: "CMTimebaseCopyMasterTimebase(_:)"
framework: coremedia
role: symbol
role_heading: Function
path: "coremedia/cmtimebasecopymastertimebase(_:)"
---

# CMTimebaseCopyMasterTimebase(_:)

Returns the immediate host timebase of a timebase.

## Declaration

```swift
func CMTimebaseCopyMasterTimebase(_ timebase: CMTimebase) -> CMTimebase?
```

## See Also

### Deprecations

- [CMTimebaseSetRateAndAnchorTime(_:rate:anchorTime:immediateMasterTime:)](coremedia/cmtimebasesetrateandanchortime(_:rate:anchortime:immediatemastertime:).md)
- [CMTimebaseGetMasterTimebase(_:)](coremedia/cmtimebasegetmastertimebase(_:).md)
- [CMTimebaseGetMasterClock(_:)](coremedia/cmtimebasegetmasterclock(_:).md)
- [CMTimebaseGetMaster(_:)](coremedia/cmtimebasegetmaster(_:).md)
- [CMTimebaseGetUltimateMasterClock(_:)](coremedia/cmtimebasegetultimatemasterclock(_:).md)
- [CMTimebaseSetMasterClock(_:_:)](coremedia/cmtimebasesetmasterclock(_:_:).md)
- [CMTimebaseSetMasterTimebase(_:_:)](coremedia/cmtimebasesetmastertimebase(_:_:).md)
- [CMTimebaseSetAnchorTime(_:timebaseTime:immediateMasterTime:)](coremedia/cmtimebasesetanchortime(_:timebasetime:immediatemastertime:).md)
- [CMTimebaseCopyMaster(_:)](coremedia/cmtimebasecopymaster(_:).md)
- [CMTimebaseCopyMasterClock(_:)](coremedia/cmtimebasecopymasterclock(_:).md)
- [CMTimebaseCopyUltimateMasterClock(_:)](coremedia/cmtimebasecopyultimatemasterclock(_:).md)
- [CMTimebaseCreateWithMasterClock(allocator:masterClock:timebaseOut:)](coremedia/cmtimebasecreatewithmasterclock(allocator:masterclock:timebaseout:).md)
- [CMTimebaseCreateWithMasterTimebase(allocator:masterTimebase:timebaseOut:)](coremedia/cmtimebasecreatewithmastertimebase(allocator:mastertimebase:timebaseout:).md)