---
title: CGBitmapContextReleaseDataCallback
framework: coregraphics
role: symbol
role_heading: Type Alias
path: coregraphics/cgbitmapcontextreleasedatacallback
---

# CGBitmapContextReleaseDataCallback

A callback function used to release data associate with the bitmap context.

## Declaration

```swift
typealias CGBitmapContextReleaseDataCallback = (UnsafeMutableRawPointer?, UnsafeMutableRawPointer?) -> Void
```

## Discussion

Discussion The releaseInfo parameter contains the contextual data that you passed to the CGContext/init(data:width:height:bitsPerComponent:bytesPerRow:space:bitmapInfo:releaseCallback:releaseInfo:) function. The data parameter contains a pointer to the bitmap data for you to release.