使用 libspotifydotnet 流式传输音频(Spotify - libspotify)

Streaming audio using libspotifydotnet (Spotify - libspotify)

查看 this, this, and this 帖子后,我了解到我必须使用 NAudio 之类的东西来 stream 音频,并且播放歌曲是通过以下方式完成的:

libspotify.sp_session_player_load(_sessionPtr, trackPtr);
libspotify.sp_session_player_play(_sessionPtr, true);

现在,如果我理解正确的话,我正在接收 stream 作为原始 PCM 数据。我怎样才能访问这些数据?

根据文档,我看到我必须填充 libspotify.sp_audioformat

我该怎么做呢?从哪里来?

我正在检查 this 项目 (Jamcast),他们做了类似的事情:

libspotify.sp_audioformat format = (libspotify.sp_audioformat)Marshal.PtrToStructure(formatPtr, typeof(libspotify.sp_audioformat));

有人能给我指出正确的方向吗? 我完全不知道如何检索 stream

最后,我跟进了this, and this问题。他们帮了我很多。

我不得不这样做:

public static libspotify.sp_error LoadPlayer(IntPtr trackPtr)
{
    bufferedWaveProvider = new BufferedWaveProvider(new WaveFormat());
    bufferedWaveProvider.BufferDuration = TimeSpan.FromSeconds(120);

    return libspotify.sp_session_player_load(_sessionPtr, trackPtr);
}

public static void Play()
{
    libspotify.sp_session_player_play(_sessionPtr, true);

    IWavePlayer waveOutDevice = new WaveOut();
    waveOutDevice.Init(bufferedWaveProvider);
    waveOutDevice.Play();
    while (waveOutDevice.PlaybackState == PlaybackState.Playing)
    {
        Thread.Sleep(100);
    }   
}

private static int music_delivery(IntPtr sessionPtr, IntPtr formatPtr, IntPtr framesPtr, int num_frame)
{
    if (num_frame == 0)
        return 0;

    libspotify.sp_audioformat format = (libspotify.sp_audioformat)Marshal.PtrToStructure(formatPtr, typeof(libspotify.sp_audioformat));
    byte[] buffer = new byte[num_frame * sizeof(Int16) * format.channels];
    Marshal.Copy(framesPtr, buffer, 0, buffer.Length);

    bufferedWaveProvider.AddSamples(buffer, 0, num_frame * sizeof(Int16) * format.channels);

    if (Session.OnAudioDataArrived != null)            
        Session.OnAudioDataArrived(buffer);

    return num_frame;

}