如何将Swift中的CMSampleBuffer转换为数据？

Question

我需要将CMSampleBuffer转换为Data格式。我正在使用一个第三方框架进行音频相关任务。该框架为我提供了CMSampleBuffer对象中的流媒体（即实时音频）音频。

像这样：

func didAudioStreaming(audioSample: CMSampleBuffer!) { 
    //Here I need to conver this to Data format. 
    //Because I am using GRPC framework for Audio Recognization, 
} 

请提供给我的步骤来转换CMSampleBuffer到Data。

FYI

let formatDesc:CMFormatDescription? = CMSampleBufferGetFormatDescription(audioSample) 

    <CMAudioFormatDescription 0x17010d890 [0x1b453ebb8]> { 
    mediaType:'soun' 
    mediaSubType:'lpcm' 
    mediaSpecific: { 
     ASBD: { 
      mSampleRate: 16000.000000 
      mFormatID: 'lpcm' 
      mFormatFlags: 0xc 
      mBytesPerPacket: 2 
      mFramesPerPacket: 1 
      mBytesPerFrame: 2 
      mChannelsPerFrame: 1 
      mBitsPerChannel: 16  } 
     cookie: {(null)} 
     ACL: {(null)} 
     FormatList Array: {(null)} 
    } 
    extensions: {(null)} 
} 

Answer 1

尝试下面的代码CMSampleBuffer转换为NSData的。

let imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer) 
CVPixelBufferLockBaseAddress(imageBuffer!, CVPixelBufferLockFlags(rawValue: 0)) 
let bytesPerRow = CVPixelBufferGetBytesPerRow(imageBuffer!) 
let height = CVPixelBufferGetHeight(imageBuffer!) 
let src_buff = CVPixelBufferGetBaseAddress(imageBuffer!) 
let data = NSData(bytes: src_buff, length: bytesPerRow * height) 
CVPixelBufferUnlockBaseAddress(imageBuffer!, CVPixelBufferLockFlags(rawValue: 0)) 

编辑 -

对于AudioBuffer使用下面的代码 -

var audioBufferList = AudioBufferList() 
var data = Data() 
var blockBuffer : CMBlockBuffer? 

CMSampleBufferGetAudioBufferListWithRetainedBlockBuffer(sampleBuffer, nil, &audioBufferList, MemoryLayout<AudioBufferList>.size, nil, nil, 0, &blockBuffer) 

let buffers = UnsafeBufferPointer<AudioBuffer>(start: &audioBufferList.mBuffers, count: Int(audioBufferList.mNumberBuffers)) 

for audioBuffer in buffers { 
    let frame = audioBuffer.mData?.assumingMemoryBound(to: UInt8.self) 
    data.append(frame!, count: Int(audioBuffer.mDataByteSize)) 
}