annotate filter/gamma_tone.h @ 0:5242703e91d3 tip

Initial checkin for AIM92 aimR8.2 (last updated May 1997).

/*
    Copyright (c) Applied Psychology Unit, Medical Research Council. 1988, 1989
    ===========================================================================

    Permission to use, copy, modify, and distribute this software without fee 
    is hereby granted for research purposes, provided that this copyright 
    notice appears in all copies and in all supporting documentation, and that 
    the software is not redistributed for any fee (except for a nominal shipping 
    charge). Anyone wanting to incorporate all or part of this software in a
    commercial product must obtain a license from the Medical Research Council.

    The MRC makes no representations about the suitability of this 
    software for any purpose.  It is provided "as is" without express or implied 
    warranty.
 
    THE MRC DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING 
    ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL THE
    A.P.U. BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY 
    DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN 
    AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 
    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/

/*

	 ==============================================================
	  gamma_tone.h - portable recursive auditory filter bank code.
	 ==============================================================

		   J. Holdsworth - 23rd February 1988.


    Copywright (c) Applied Psychology Unit, Medical Research Council. 1988.
    =======================================================================


    Release 2: 5th July 1988.
    Release 3: 20th September 1988.
    Rewrite :  21st January 1988.

*/

#define   _GAMMA_TONE_H_

#define   GT_IDENT_STRING    "@(#)gamma_tone.h	1.5 J. Holdsworth (MRC-APU) 1/30/90\n"


/* number of bits significant in input data */

#define   bits_significant   12


/* structure storing information common to all channels in filter */

typedef struct _bank_info FilterBankInfo, *FilterBankInfoPtr ;

struct _bank_info { double samplerate, b_scalar, max_desired_advance_time ;
	   int order, phase_comp ; } ;


/* structure storing information specific to state of particualr channel's filter */

typedef char FilterChannelInfo, *FilterChannelInfoPtr ;


extern double *GenerateCenterFrequencies(
#ifdef vaxc
double min_cf, double max_cf, double erb_density
#endif
) ;

extern int NumberCenterFrequencies(
#ifdef vaxc
int min_cf, double max_cf, double erb_density
#endif
) ;

extern double *NumberedCenterFrequencies(
#ifdef vaxc
double min_cf, double max_cf, int channels
#endif
) ;

extern  double bandwidth_normalisation() ;


extern  FilterBankInfo    *InitGammaToneFilterBank() ;
extern  FilterChannelInfo *InitGammaToneFilterChannel() ;
extern  void EndChannel() ;
extern  void EndFilter() ;

extern  int FilterShortDataArray() ;
extern  int RealFilterShortDataArray() ;
extern  int FilterIntDataArray() ;
extern  int RealFilterIntDataArray() ;
extern  int RealFilterDoubleDataArray() ;

/* envelope functions */

extern  int EnvelopeShortDataArray() ;
extern  int RealEnvelopeShortDataArray() ;


/* for compatability with release 1 */

#define  InitGammaToneFilter InitGammaToneFilterBank
#define  FilterDataArray     FilterShortDataArray
#define  erb( _f )           Erb( _f )
#define  erb_rate( _f )      ErbRate( _f )
#define  f_of_erb_rate( _E ) FofErbRate( _E )
#define  bandwidth_divisor   bandwidth_normalisation

/* missing parameters availiable as globl variables */

extern double filterDefaultGain ;
extern int filterDefaultInputBits ;