# CMSampleBufferSetDataBufferFromAudioBufferList(_:blockBufferAllocator:blockBufferMemoryAllocator:flags:bufferList:) Creates a block buffer that contains a copy of the data from an audio buffer list. ``` func CMSampleBufferSetDataBufferFromAudioBufferList(_ sbuf: CMSampleBuffer, blockBufferAllocator blockBufferStructureAllocator: CFAllocator?, blockBufferMemoryAllocator blockBufferBlockAllocator: CFAllocator?, flags: UInt32, bufferList: UnsafePointer) -> OSStatus ``` ## Parameters `sbuf` The `CMSampleBuffer` being modified. `blockBufferStructureAllocator` Allocator to use when creating the `CMBlockBuffer` structure. `blockBufferBlockAllocator` Allocator to use for memory block held by the `CMBlockBuffer`. `flags` Flags controlling operation. `bufferList` Buffer list whose data will be copied into the new `CMBlockBuffer`. ## Return Value A result code. See [Sample Buffer Error Codes](/documentation/CoreMedia/sample-buffer-errors). ## Discussion Creates a `CMBlockBuffer` containing a copy of the data from the `AudioBufferList`, and sets that as the sample buffer’s data buffer. The resulting buffer(s) in the sample buffer will be 16-byte-aligned if `kCMSampleBufferFlag_AudioBufferList_Assure16ByteAlignment` is passed in. --- 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)