<!--
{
  "availability" : [
    "iOS: 7.0.0 -",
    "iPadOS: 7.0.0 -",
    "macCatalyst: 13.1.0 -",
    "macOS: 10.8.0 -",
    "tvOS: 9.0.0 -",
    "visionOS: 1.0.0 -",
    "watchOS: 2.0.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "ImageIO",
  "identifier" : "/documentation/ImageIO/kCGImageDestinationMergeMetadata",
  "metadataVersion" : "0.1.0",
  "role" : "Global Variable",
  "symbol" : {
    "kind" : "Global Variable",
    "modules" : [
      "Image I/O"
    ],
    "preciseIdentifier" : "c:@kCGImageDestinationMergeMetadata"
  },
  "title" : "kCGImageDestinationMergeMetadata"
}
-->

# kCGImageDestinationMergeMetadata

A Boolean value that indicates whether to merge new metadata with the image’s existing metadata.

```
let kCGImageDestinationMergeMetadata: CFString
```

## Discussion

The value of this key must be a <doc://com.apple.documentation/documentation/CoreFoundation/CFBoolean> value. The default value is <doc://com.apple.documentation/documentation/CoreFoundation/kCFBooleanFalse>.

If you set this key to <doc://com.apple.documentation/documentation/CoreFoundation/kCFBooleanTrue>, the image destination merges the information in the [`kCGImageDestinationMetadata`](/documentation/ImageIO/kCGImageDestinationMetadata) key with the image’s existing metadata. Specifically, if a tag doesn’t exist in the source, the destination adds it. If the tag exists in the source, the destination updates its value. To remove a tag, set the value of the appropriate key to <doc://com.apple.documentation/documentation/CoreFoundation/kCFNull>.

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)