---
title: "vImageCVImageFormat_SetUserData(_:_:_:)"
framework: accelerate
role: symbol
role_heading: Function
path: "accelerate/vimagecvimageformat_setuserdata(_:_:_:)"
---

# vImageCVImageFormat_SetUserData(_:_:_:)

Sets the user data of a Core Video image format.

## Declaration

```swift
func vImageCVImageFormat_SetUserData(_ format: vImageCVImageFormat, _ userData: UnsafeMutableRawPointer!, _ userDataReleaseCallback: ((vImageCVImageFormat?, UnsafeMutableRawPointer?) -> Void)!) -> vImage_Error
```

## Parameters

- `format`: The Core Video image format to update.
- `userData`: The new user data for the format.
- `userDataReleaseCallback`: The callback the system calls when it releases the doc://com.apple.accelerate/documentation/Accelerate/vImageCVImageFormat instance or overwrites the userData pointer.

## Return Value

Return Value kvImageNoError; otherwise, one of the error codes in Data Types and Constants.

## Discussion

Discussion

## See Also

### Querying and setting the user data

- [vImageCVImageFormat_GetUserData(_:)](accelerate/vimagecvimageformat_getuserdata(_:).md)