---
title: QLThumbnailRepresentation
framework: quicklookthumbnailing
role: symbol
role_heading: Class
path: quicklookthumbnailing/qlthumbnailrepresentation
---

# QLThumbnailRepresentation

Information about the thumbnail that the thumbnail generator returns.

## Declaration

```swift
class QLThumbnailRepresentation
```

## Overview

Overview QuickLook Thumbnailing is a non-UI framework, so your app doesn’t have to link to either UIKit or AppKit. Quicklook Thumbnailing generates a thumbnail as a Core Graphics image object and makes the thumbnail available as the cgImage property. If an app links to AppKit or UIKit, the thumbnail is available through the nsImage or uiImage properties. For more information on the different types of thumbnails that QLThumbnailGenerator can create, see QLThumbnailGenerator.Request.RepresentationTypes.

## Topics

### Thumbnail Images

- [cgImage](quicklookthumbnailing/qlthumbnailrepresentation/cgimage.md)
- [nsImage](quicklookthumbnailing/qlthumbnailrepresentation/nsimage.md)
- [uiImage](quicklookthumbnailing/qlthumbnailrepresentation/uiimage.md)
- [type](quicklookthumbnailing/qlthumbnailrepresentation/type.md)
- [contentRect](quicklookthumbnailing/qlthumbnailrepresentation/contentrect.md)
- [QLThumbnailRepresentation.RepresentationType](quicklookthumbnailing/qlthumbnailrepresentation/representationtype.md)

## Relationships

### Inherits From

- [NSObject](objectivec/nsobject-swift.class.md)

### Conforms To

- [CVarArg](swift/cvararg.md)
- [CustomDebugStringConvertible](swift/customdebugstringconvertible.md)
- [CustomStringConvertible](swift/customstringconvertible.md)
- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)
- [NSObjectProtocol](objectivec/nsobjectprotocol.md)

## See Also

### Thumbnail Generation

- [Creating Quick Look Thumbnails to Preview Files in Your App](quicklookthumbnailing/creating-quick-look-thumbnails-to-preview-files-in-your-app.md)
- [QLThumbnailGenerator](quicklookthumbnailing/qlthumbnailgenerator.md)