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# CMMetadataFormatDescriptionCreateByMergingMetadataFormatDescriptions(allocator:sourceDescription:otherSourceDescription:formatDescriptionOut:)

Creates a metadata format description object by merging with another description.

```
func CMMetadataFormatDescriptionCreateByMergingMetadataFormatDescriptions(allocator: CFAllocator?, sourceDescription: CMMetadataFormatDescription, otherSourceDescription: CMMetadataFormatDescription, formatDescriptionOut: UnsafeMutablePointer<CMMetadataFormatDescription?>) -> OSStatus
```

## Parameters

`allocator`

Allocator to use for allocating the CMBlockBuffer object. May be NULL.

`sourceDescription`

The metadata format description to merge.

`otherSourceDescription`

Another metadata format description to merged

`formatDescriptionOut`

Returns newly created metadata `CMFormatDescription`.

## Discussion

---

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