---
title: "SecTransformCopyExternalRepresentation(_:)"
framework: security
role: symbol
role_heading: Function
path: "security/sectransformcopyexternalrepresentation(_:)"
---

# SecTransformCopyExternalRepresentation(_:)

Creates a dictionary that contains enough information to be able to recreate a transform.

## Declaration

```swift
func SecTransformCopyExternalRepresentation(_ transformRef: SecTransform) -> CFDictionary
```

## Parameters

- `transformRef`: The transformRef to be externalized.

## Discussion

Discussion This function returns a CFDictionaryRef that contains sufficient information to be able to recreate this transform. You can pass this CFDictionaryRef to SecTransformCreateFromExternalRepresentation to be able to recreate the transform. The dictionary can also be written out to disk using the techniques described here. http://developer.apple.com/mac/library/documentation/CoreFoundation/Conceptual/CFPropertyLists/Articles/Saving.html