提取quicktime文件中的每个音频通道(extract every audio-channel in a quicktime file)

 我想用QuickTime-API提取quicktime电影中的每个音频通道。 这意味着如果文件有5.1环绕声，我最后想要6个音频文件。 但目前我不知道如何管理它。 到现在为止我有： 
 
OSStatus err = noErr;
MovieAudioExtractionRef extractionSessionRef = nil;
Boolean allChannelsDiscrete = true;
int flags;
int numFrames;
AudioBufferList *mBufferList;
err = MovieAudioExtractionBegin(movie, 0, &extractionSessionRef); 


// disable mixing of audio channels
err = MovieAudioExtractionSetProperty(extractionSessionRef,
  kQTPropertyClass_MovieAudioExtraction_Movie,
  kQTMovieAudioExtractionMoviePropertyID_AllChannelsDiscrete,
  sizeof (Boolean), &allChannelsDiscrete);

err = MovieAudioExtractionFillBuffer(extractionSessionRef, &numFrames, 
  mBufferList, &flags);
if (flags & kQTMovieAudioExtractionComplete)
{
    // extraction complete!
}
err = MovieAudioExtractionEnd(extractionSessionRef);
 
 问题是我不知道如何获得mBufferList以及如何将每个通道导出为WAV 48kHz。 你可以帮我吗？ 该示例来自此页面 。 

I want to extract every audio channel in a quicktime movie with the QuickTime-API. That means if the file has 5.1 surround, i want 6 audio files in the end. But at the moment I don't know how to manage that. Until now I have:
 
OSStatus err = noErr;
MovieAudioExtractionRef extractionSessionRef = nil;
Boolean allChannelsDiscrete = true;
int flags;
int numFrames;
AudioBufferList *mBufferList;
err = MovieAudioExtractionBegin(movie, 0, &extractionSessionRef); 


// disable mixing of audio channels
err = MovieAudioExtractionSetProperty(extractionSessionRef,
  kQTPropertyClass_MovieAudioExtraction_Movie,
  kQTMovieAudioExtractionMoviePropertyID_AllChannelsDiscrete,
  sizeof (Boolean), &allChannelsDiscrete);

err = MovieAudioExtractionFillBuffer(extractionSessionRef, &numFrames, 
  mBufferList, &flags);
if (flags & kQTMovieAudioExtractionComplete)
{
    // extraction complete!
}
err = MovieAudioExtractionEnd(extractionSessionRef);
 
The problem is that I don't know how to get mBufferList and how to export every channel as WAV 48kHz. Can you help me? The example is from this page.

原文：https://stackoverflow.com/questions/3184453