# withPixelBufferIfAvailable(_:) Reads the underlying pixel buffer. ``` func withPixelBufferIfAvailable(_ body: (CVPixelBuffer) throws -> R) rethrows -> R? ``` ## Parameters `body` The closure to run with the pixel buffer. ## Return Value The value returned from body, unless the shaped array doesn’t use a pixel buffer backing, in which case the method ignores body and returns nil. ## Discussion Use this method to read the contents of the underlying pixel buffer. The pixel buffer is read only. Do not write to it. ```swift let array = MLShapedArray(mutating: pixelBuffer, shape: [2, 3]) array.withPixelBuffer { backingPixelBuffer in // read backingPixelBuffer here. } ``` --- Copyright © 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)