#define OPT_RAW_CHANNELS M4AF_FOURCC('r','c','h','n')
#define OPT_RAW_RATE M4AF_FOURCC('r','r','a','t')
#define OPT_RAW_FORMAT M4AF_FOURCC('r','f','m','t')
#define OPT_RAW_CHANNELS M4AF_FOURCC('r','c','h','n')
#define OPT_RAW_RATE M4AF_FOURCC('r','r','a','t')
#define OPT_RAW_FORMAT M4AF_FOURCC('r','f','m','t')