typedef enum {
  VM_AUDIO_FORMAT_NONE = -1,
  VM_AUDIO_FORMAT_AMR = 3,
  VM_AUDIO_FORMAT_MP3 = 5,
  VM_AUDIO_FORMAT_AAC = 6,
  VM_AUDIO_FORMAT_WAV = 13,
  VM_AUDIO_FORMAT_MIDI = 17,
  VM_AUDIO_FORMAT_IMELODY = 18,
  VM_AUDIO_FORMAT_OTHER = 100
} VM_AUDIO_FORMAT;