---
title: typeIdentifierHint
framework: coreimage
role: symbol
role_heading: Type Property
path: coreimage/ciimageoption/typeidentifierhint
---

# typeIdentifierHint

The uniform type identifier string to use in cases where a file’s format cannot be conclusively determined based solely on its contents.

## Declaration

```swift
static let typeIdentifierHint: CIImageOption
```

## Discussion

Discussion The value of this key should be an NSString containing a hint. It is most commonly needed for some RAW file formats which can also be interpreted as TIFF files. This option is only supported by these APIs: /CIImage/imageWithContentsOfURL:options: /CIImage/initWithContentsOfURL:options: /CIImage/imageWithData:options: /CIImage/initWithData:options: note: The key kCGImageSourceTypeIdentifierHint key can also be used for this purpose.