# AVReadOnlyAudioPCMBuffer A read-only, Sendable audio buffer for safe concurrent access. ``` struct AVReadOnlyAudioPCMBuffer ``` ## Topics ### Creating a read-only buffer [`init(copying: AVAudioPCMBuffer)`](/documentation/AVFAudio/AVReadOnlyAudioPCMBuffer/init(copying:)) Creates a read-only buffer by copying audio data from an existing PCM buffer. [`init(format: AVAudioFormat, frameCapacity: Int, initializingWith: (UnsafeMutablePointer) throws -> Void) throws`](/documentation/AVFAudio/AVReadOnlyAudioPCMBuffer/init(format:frameCapacity:initializingWith:)) Creates a read-only buffer by allocating and initializing audio data via closure. [`init(unsafeRetaining: sending AVAudioPCMBuffer)`](/documentation/AVFAudio/AVReadOnlyAudioPCMBuffer/init(unsafeRetaining:)) Creates a read-only buffer by retaining the existing PCM buffer without copying. ### Getting buffer properties [`var format: AVAudioFormat`](/documentation/AVFAudio/AVReadOnlyAudioPCMBuffer/format) [`var frameCapacity: Int`](/documentation/AVFAudio/AVReadOnlyAudioPCMBuffer/frameCapacity) [`var frameLength: Int`](/documentation/AVFAudio/AVReadOnlyAudioPCMBuffer/frameLength) [`var stride: Int`](/documentation/AVFAudio/AVReadOnlyAudioPCMBuffer/stride) ### Accessing channel data [`func channelData(Int) -> AVReadOnlyAudioPCMBuffer.ChannelData`](/documentation/AVFAudio/AVReadOnlyAudioPCMBuffer/channelData(_:)) Returns read-only access to a specific channel’s data. [`func withUnsafeAudioBufferList((UnsafePointer) throws -> R) rethrows -> R`](/documentation/AVFAudio/AVReadOnlyAudioPCMBuffer/withUnsafeAudioBufferList(_:)) Provides scoped read-only access to the audio buffer list. [`enum ChannelData`](/documentation/AVFAudio/AVReadOnlyAudioPCMBuffer/ChannelData) Represents read-only channel data. ## Relationships ### Conforms To [`SendableMetatype`](/documentation/Swift/SendableMetatype) [`Sendable`](/documentation/Swift/Sendable) --- 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)