Question

我正在努力使用此API和Swift中的语法

>>>from os import cpu_count
>>>eval('[1,cores]', {'__builtins__': None}, {'cores': cpu_count()})
[1, 8]

我不知道（AudioBuffer）与（）的含义是什么？任何想法以及如何初始化它？这来自标题：

audioBufferList = AudioBufferList(mNumberBuffers: 2, mBuffers: (AudioBuffer))

Answer 1

这是一种初始化AudioBufferList的方法，它有一个空的单声道缓冲区数组，你可以传递给音频单元调用，例如AudioUnitRender（），然后根据需要分配和填充缓冲区：

var bufferList = AudioBufferList(
        mNumberBuffers: 1,
        mBuffers: AudioBuffer(
            mNumberChannels: UInt32(1),
            mDataByteSize: 1024,
            mData: nil))

Answer 2

通过使用AVAudioPCMBuffer类以以下方式解决了该问题：

import AVFoundation

// noninterleaved stereo data
let processingFormat = AVAudioFormat(
  commonFormat: .pcmFormatFloat32,
  sampleRate: 44100,
  channels: 2,
  interleaved: false
)!

// this line also creates AudioBufferList instance.
let buffer = AVAudioPCMBuffer(
  pcmFormat: processingFormat,
  frameCapacity: 1024)!
// this line updates mDataByteSize properties
buffer.frameLength = 1024

let bufferList: UnsafePointer<AudioBufferList> = buffer.audioBufferList

print(bufferList.pointee) // Prints: AudioBufferList(mNumberBuffers: 2, mBuffers: __C.AudioBuffer(mNumberChannels: 1, mDataByteSize: 4096, mData: Optional(0x00007ff253840e00)))

AudioBufferList在Swift中分配

2 个答案: