Playing WAV data with AVAudioEngine

Question

Currently, I'm getting an EXC_BAD_ACCESS error on the audio thread, and I'm trying to deduce what is going wrong. When converting .wav file data from Data to an AVAudioPCMBuffer, do I need to strip the RIFF header first? import AVFoundation public class Player : NSObject { let engine = AVAudioEngine() public override init() { super.init() do { let _ = engine.mainMixerNode try engine.start() } catch { print("Player error: \(error)") } } @objc public func play(_ data: Data) { let format = AVAudioFormat(commonFormat: .pcmFormatInt16, sampleRate: 48000, channels: 2, interleaved: true)! let buffer = data.toPCMBuffer(format: format)! let player = AVAudioPlayerNode() engine.attach(player) engine.connect(player, to: engine.mainMixerNode, format: nil) player.scheduleBuffer(buffer, at: nil, completionCallbackType: .dataPlayedBack) { callbackType in // Nothing in here. } player.play() } } Here's the toPCMBuffer extension: // Taken from: https://stackoverflow.com/a/52731480/2228559 extension Data { func toPCMBuffer(format: AVAudioFormat) -> AVAudioPCMBuffer? { let streamDesc = format.streamDescription.pointee let frameCapacity = UInt32(count) / streamDesc.mBytesPerFrame guard let buffer = AVAudioPCMBuffer(pcmFormat: format, frameCapacity: frameCapacity) else { return nil } buffer.frameLength = buffer.frameCapacity let audioBuffer = buffer.audioBufferList.pointee.mBuffers withUnsafeBytes { addr in audioBuffer.mData?.copyMemory(from: addr, byteCount: Int(audioBuffer.mDataByteSize)) } return buffer } } Note: I cannot use AVAudioFile because the .wav file data is loaded over-the-wire. JavaScript questions and answers, JavaScript questions pdf, JavaScript question bank, JavaScript questions and answers pdf, mcq on JavaScript pdf, JavaScript questions and solutions, JavaScript mcq Test , Interview JavaScript questions, JavaScript Questions for Interview, JavaScript MCQ (Multiple Choice Questions)

Answer 1

IDK, but my mac crashes if I play interleaved AVAudioPCMBuffers, and garbled audio if they're not float data, so you could convert to non-interleaved float data: @objc public func play(_ data: Data) { let sampleRate: Double = 48000 let interleavedFormat = AVAudioFormat(commonFormat: .pcmFormatInt16, sampleRate: sampleRate, channels: 2, interleaved: true)! let interleavedBuffer = data.toPCMBuffer(format: interleavedFormat)! let nonInterleavedFormat = AVAudioFormat(commonFormat: .pcmFormatFloat32, sampleRate: sampleRate, channels: 2, interleaved: false)! let nonInterleavedBuffer = AVAudioPCMBuffer(pcmFormat: nonInterleavedFormat, frameCapacity: interleavedBuffer.frameCapacity)! nonInterleavedBuffer.frameLength = interleavedBuffer.frameLength let converter = AVAudioConverter(from: interleavedFormat, to: nonInterleavedFormat)! try! converter.convert(to: nonInterleavedBuffer, from: interleavedBuffer) let player = AVAudioPlayerNode() engine.attach(player) engine.connect(player, to: engine.mainMixerNode, format: nil) player.scheduleBuffer(nonInterleavedBuffer, at: nil, completionCallbackType: .dataPlayedBack) { callbackType in // Nothing in here. } player.play() } extension Data { func toPCMBuffer(format: AVAudioFormat) -> AVAudioPCMBuffer? { assert(format.isInterleaved) let streamDesc = format.streamDescription.pointee let frameCapacity = UInt32(count) / streamDesc.mBytesPerFrame guard let buffer = AVAudioPCMBuffer(pcmFormat: format, frameCapacity: frameCapacity) else { return nil } buffer.frameLength = buffer.frameCapacity let b = UnsafeMutableBufferPointer(start: buffer.int16ChannelData![0], count: buffer.stride * Int(frameCapacity)) let bytesCopied = self.copyBytes(to: b) assert(bytesCopied == count) return buffer } }