let asset = AVAsset(url: URL(fileURLWithPath: "asset/p2a2.aif"))
let track = asset.tracks[0]
let desc = track.formatDescriptions[0] as! CMAudioFormatDescription
let basic = CMAudioFormatDescriptionGetStreamBasicDescription(desc)
print(basic?.pointee.mSampleRate)

我使用的是Swift，所以它看起来有点不同，但它仍然可以与Obj-C一起工作。

print(track.naturalTimeScale)

似乎也给予了正确的答案，但我有点担心，因为这个名字。

使用Swift和AVFoundation：

let url = Bundle.main.url(forResource: "audio", withExtension: "m4a")!
let asset = AVAsset(url: url)
if let firstTrack = asset.tracks.first {
    print("bitrate: \(firstTrack.estimatedDataRate)")
}

要在元数据中查找更多信息，您还可以参考：https://developer.apple.com/documentation/avfoundation/avassettrackhttps://developer.apple.com/documentation/avfoundation/media_assets_playback_and_editing/finding_metadata_values

找到了。我正在使用MTAudioProcessingTap，所以在prepare（）函数中我可以用途：

void prepare(MTAudioProcessingTapRef tap, CMItemCount maxFrames, const AudioStreamBasicDescription *processingFormat)
{
    sampleRate = processingFormat->mSampleRate;
    NSLog(@"Preparing the Audio Tap Processor");
}

private func getFormat(localUrl:String)->[String: Any?]{
    let audioUrl = URL.init(string: localUrl)
    let file=try! AVAudioFile(forReading: audioUrl!)
    let format=file.fileFormat
    return [
        "sampleRate":format.sampleRate,
        "channelCount":format.channelCount
    ]
}