---
title: "dictionaryRepresentation(forAuxiliaryDataType:)"
framework: avfoundation
role: symbol
role_heading: Instance Method
path: "avfoundation/avsemanticsegmentationmatte/dictionaryrepresentation(forauxiliarydatatype:)"
---

# dictionaryRepresentation(forAuxiliaryDataType:)

Returns a dictionary of primitive map information to use when writing an image file with a semantic segmentation matte.

## Declaration

```swift
func dictionaryRepresentation(forAuxiliaryDataType outAuxDataType: AutoreleasingUnsafeMutablePointer<NSString?>?) -> [AnyHashable : Any]?
```

## Parameters

- `outAuxDataType`: On output, the auxiliary data type to be used when calling the ImageIO framework’s doc://com.apple.documentation/documentation/ImageIO/CGImageDestinationAddAuxiliaryDataInfo(_:_:_:) function. Currently supported auxiliary data types are enumerated in CGImageProperties.

## Return Value

Return Value A dictionary of CGImageDestination-compatible semantic segmentation matte information, or nil if the auxiliary data type is unsupported.

## See Also

### Creating a segmentation matte

- [init(fromImageSourceAuxiliaryDataType:dictionaryRepresentation:)](avfoundation/avsemanticsegmentationmatte/init(fromimagesourceauxiliarydatatype:dictionaryrepresentation:).md)
- [replacingSemanticSegmentationMatte(with:)](avfoundation/avsemanticsegmentationmatte/replacingsemanticsegmentationmatte(with:).md)
- [applyingExifOrientation(_:)](avfoundation/avsemanticsegmentationmatte/applyingexiforientation(_:).md)