AVAudioRecorder！我需要有从0到120 ios swift的振幅的分贝值？

import AVFoundation

// 创建音频文件的URL
let audioURL = URL(fileURLWithPath: "path_to_audio_file")

// 创建录音设置
let settings = [
    AVFormatIDKey: kAudioFormatAppleLossless,
    AVEncoderAudioQualityKey: AVAudioQuality.max.rawValue,
    AVEncoderBitRateKey: 320000,
    AVNumberOfChannelsKey: 2,
    AVSampleRateKey: 44100.0
] as [String : Any]

// 创建AVAudioRecorder实例
var audioRecorder: AVAudioRecorder?

do {
    audioRecorder = try AVAudioRecorder(url: audioURL, settings: settings)
} catch {
    print("Failed to create audio recorder: \(error)")
}

// 开始录制音频
audioRecorder?.record()

// 定时获取分贝值
let timer = Timer.scheduledTimer(withTimeInterval: 0.1, repeats: true) { _ in
    // 获取平均分贝值
    let decibel = audioRecorder?.averagePower(forChannel: 0) ?? 0.0
    
    // 将分贝值映射到0到120的振幅范围内
    let amplitude = (decibel + 120) * (120 / 160)
    
    print("Amplitude: \(amplitude)")
    
    // 判断是否达到目标振幅，达到后停止录制音频
    if amplitude >= 120 {
        audioRecorder?.stop()
        timer.invalidate()
    }
}

RunLoop.current.add(timer, forMode: .common)
RunLoop.current.run()