enum
{
  kOkOnRC = cmOkRC,
  kDspProcFailOnRC,
  kDspAudioFileFailOnRC,
  kDspTextFileFailOnRC,
};

typedef cmRC_t     cmOnRC_t;
typedef cmHandle_t cmOnH_t;

enum { kNoneFiltId, kSmoothFiltId, kMedianFiltId };

typedef struct
{
  double   wndMs;
  unsigned hopFact;
  unsigned audioChIdx;
  
  unsigned wndFrmCnt;    // Detection window length
  double   preWndMult;   // Detection window stretch factor prior to current location.
  double   threshold;    // Spectal flux detection threshold
  double   maxFrqHz;     // Ignore frequencies above maxFrqHz during processing.
  double   filtCoeff;    // smoothing filter coeff (-.7)
  double   medFiltWndMs; // median filter window in milliseconds
  unsigned filterId;     // kSmoothFiltId || kMedianFiltId
  double   preDelayMs;   // move each detection preDelayMs backwards in time on the audio output. (compensates for detection delay due to filtering)
  
  
} cmOnsetCfg_t;

extern cmOnH_t cmOnsetNullHandle;

cmOnRC_t cmOnsetInitialize( cmCtx_t* c, cmOnH_t* hp );

cmOnRC_t cmOnsetFinalize( cmOnH_t* hp );

bool     cmOnsetIsValid( cmOnH_t h );

cmOnRC_t cmOnsetProc( 
cmOnH_t h, 
const cmOnsetCfg_t* cfg, 
const cmChar_t* inAudioFn );

// Return count of detected onsets.
unsigned cmOnsetCount( cmOnH_t h );

// Return location of detected onsets as a sample offset into the file.
unsigned cmOnsetSampleIndex( cmOnH_t h, unsigned idx );

unsigned cmOnsetHopSampleCount( cmOnH_t h );

cmOnRC_t cmOnsetWrite(
cmOnH_t h,
const cmChar_t* outAudioFn, 
const cmChar_t* outTextFn);

cmOnRC_t cmOnsetTest( cmCtx_t* c );