如何在Swift中从输入音频文件生成相位反转音频文件？

import AVFoundation

let inputURL = URL(fileURLWithPath: "input_audio.wav")

let outputURL = URL(fileURLWithPath: "output_audio.wav")

let asset = AVAsset(url: inputURL)

let reader = try! AVAssetReader(asset: asset)

let writer = try! AVAssetWriter(outputURL: outputURL, fileType: .wav)

let output = AVAssetReaderAudioMixOutput(audioTracks: asset.tracks, audioSettings: nil)
reader.add(output)

let input = AVAssetWriterInput(mediaType: .audio, outputSettings: nil)
writer.add(input)

reader.startReading()

writer.startWriting()
writer.startSession(atSourceTime: .zero)

while reader.status == .reading {
    if let sampleBuffer = output.copyNextSampleBuffer() {
        // 进行相位反转处理
        // ...
        
        input.append(sampleBuffer)
    }
}

reader.cancelReading()
input.markAsFinished()
writer.finishWriting {
    // 处理完成后的操作
}